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Lumbar intervertebral fusion : - factors associated with the success of surgery Wing, Peter Courtenay 1972

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LUMBAR INTERVERTEBRAL FUSION - FACTORS ASSOCIATED WITH THE SUCCESS OF SURGERY BY PETER C. WING M.B., Ch.B., U n i v e r s i t y o f Edinburgh, Scotland, 1966. A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n the Department o f SURGERY We accept t h i s t h e s i s as conforming t o the r e q u i r e d standard. THE UNIVERSITY OF BRITISH COLUMBIA December, 1972 In presenting t h i s thesis i n p a r t i a l f u l f i l m e n t of the requirements for an advanced degree at the University of B r i t i s h Columbia, I agree that the Library s h a l l make i t f r e e l y available for reference and study. I further agree that permission for extensive copying of t h i s thesis for scholarly purposes may be granted by the Head of my Department or by h i s representatives. It i s understood that copying or publication of t h i s thesis for f i n a n c i a l gain s h a l l not be allowed without my written permission. Department of Surgery The University of B r i t i s h Columbia Vancouver 8, Canada Date December 1972. i . ABSTRACT A f t e r the performance of a p i l o t study of 28 W.W. I I veterans who had a l l had lumbar i n t e r v e r t e b r a l f u s i o n at l e a s t two years pre-v i o u s l y , an in-depth r e t r o s p e c t i v e e v a l u a t i o n was performed on one hundred (100) Workmen's Compensation Board p a t i e n t s , a l l w i t h a s i m i l a r follow-up p e r i o d subsequent to lumbar i n t e r v e r t e b r a l f u s i o n . A l l p a t i e n t c h a r a c t e r i s t i c s were evaluated, i n c l u d i n g h i s t o r i c a l , s o c i a l , p h y s i c a l , r a d i o l o g i c a l and p s y c h o l o g i c a l parameters. A success index was d e r i v e d by f a c t o r a n a l y s i s of twenty (20) v a r i a b l e s a l l r e p r e s e n t i n g v a r i o u s aspects of the p a t i e n t s c u r r e n t f u n c t i o n a l s t a t u s . This was used as a b a s i s to analyze the remaining data by m u l t i p l e c o r r e l a t i o n s . These c o r r e l a t i o n s were s t u d i e d and 55 h i g h l y " s u c c e s s " - c o r r e l a t e d v a r i a b l e s were s e l e c t e d f o r f u r t h e r f a c t o r a n a l y s i s . This f a c t o r a n a l y s i s i d e n t i f i e d e i g h t (8) f a c t o r s c l o s e l y asso-c i a t e d w i t h success or f a i l u r e o f the f u s i o n o p e r a t i o n . In order of importance they were i d e n t i f i e d thus: " N o r m a l l y " - f u n c t i o n i n g lumbar spine. M o b i l i t y of body. Freedom from n e u r o t i c i s m . High p a i n t o l e r a n c e . Minimum number of s u r g i c a l operations. Freedom from p e r s i s t e n t nerve r o o t d e f i c i t . i i . Optimism, ambition. General h e a l t h and f i t n e s s . These e i g h t orthogonal ( t o t a l l y n o n - c o r r e l a t i n g ) f a c t o r s alone independently accounted f o r approximately 80% of the variance o f "success" as determined by the s t a t i s t i c a l index. I t i s f e l t t h a t c e r t a i n o f these f a c t o r s may be e t i o l o g i c a l i n connection w i t h the low back problem and p r o s p e c t i v e work i s necessary t o shed f u r t h e r l i g h t on t h i s . The methods used i n p a t i e n t e v a l u a t i o n were examined and i t i s f e l t t h a t c e r t a i n o f these measures are inadequately o b j e c t i v e and i n v o l v e measurement of s e v e r a l f a c t o r s at one time. For example, measures of range o f 'movement as c o n v e n t i o n a l l y used i n orthopaedics were found t o show a very h i g h c o r r e l a t i o n w i t h c e r t a i n of the p s y c h o l o g i c a l measures o f abnormality. Some showed poor c o r r e l a t i o n w i t h age which i s co n t r a r y t o p u b l i s h e d data on the range of motion i n d i f f e r e n t planes determined r a d i o l o g i c a l l y . I t i s suggested that a l t e r n a t i v e methods be used which would provide g r e a t e r s p e c i f i c i t y . Increased use of q u a n t i t a t i v e r a d i o l o g i c a l methods i s suggested as t h i s provides an accurate way of comparing p a t i e n t s from a p u r e l y s t r u c t u r a l viewpoint. The p s y c h o l o g i c a l p r o f i l e of the p a t i e n t i s shown t o be of great importance as twothirds o f the p a t i e n t s showed an e l e v a t i o n of one or more Minnesota M u l t i p h a s i c P e r s o n a l i t y Inventory s c a l e s over a T-score of 70; i n a random p o p u l a t i o n t h i s f i g u r e would be approximately 31. i i i . I t i s suggested t h a t p s y c h o l o g i c a l e v a l u a t i o n should be used at a l l stages o f low back p a i n disease to a s s i s t i n management of the pa-t i e n t . P s e udarthrosis was determined to e x i s t i n the presence of two out of three r a d i o l o g i c a l f e a t u r e s : Movement at the f u s i o n s i t e on bending x-rays. Presence o f a d e f e c t i n the bone mass. P e r s i s t e n c e of the p o s t e r i o r apophyseal j o i n t s . The presence of p s e u d a r t h r o s i s d i d not c o r r e l a t e s i g n i f i c a n t l y w i t h success or f a i l u r e of the operation. I t i s s t r e s s e d that only i n f o r m a t i o n obtainable i n an accurate way of a l l p a t i e n t s was used i n t h i s study and t h i s prevented the use o f o p e r a t i v e reports, from the p a t i e n t s time o f surgery which was f r e q u e n t l y i n a c c u r a t e and was not uniform i n the i n f o r m a t i o n they provided. I t was decided not to use symptomatic i n f o r m a t i o n as r e -membered by the p a t i e n t from before h i s o p e r a t i o n as t h i s would be coloured by too many subsequent events and would not be matched by comparable p h y s i c a l , r a d i o l o g i c a l or psychometric r e s u l t s . S i m i l a r l y , success was not c o r r e l a t e d w i t h the i n d i v i d u a l surgeon as some sur-geons were represented by too few cases and some p a t i e n t s would have been seen by s e v e r a l surgeonsaat d i f f e r e n t stages i n t h e i r i l l n e s s . This e v a l u a t i o n of the c l i n i c a l and s t a t i s t i c a l methods pro-vides much i n f o r m a t i o n of use i n the c l i n i c a l and p r o s p e c t i v e e x p e r i -mental s e t t i n g . I t does not attempt to provide d e f i n i t i v e answers i v . regarding the causes of low back pain: prospective investigation i s required for this, and the nature of the required studies for this is outlined. V. INDEX OF CONTENTS Page I. INTRODUCTION 1 I I . HYPOTHESIS AND PURPOSE OF THE STUDY 3 I I I . REVIEW OF THE LITERATURE 5 IV. THE LUMBAR SPINE IN HEALTH AND DISEASE 6 Embryology and Development.... 6 Anatomy, Physiology 8 Degenerative Disease of the I n t e r v e r t e b r a l J o i n t 13 The V a s c u l a r Supply o f the Region 15 The Nerve Supply o f the Region 19 Function of the Spine 21 LUMBAR BACK PAIN DISEASE 29 The Problem of Low Back P a i n 29 The Causes of M u s c o l o s k e l e t a l Back P a i n 35 Management of Low Back P a i n 46 Lumbar I n t e r v e r t e b r a l Fusion 54 SUMMARY OF LITERATURE 62 V. MATERIALS AND METHODS 63 P i l o t Study 63 Main Phase 65 VI. RESULTS 72 P i l o t Study 72 Main Phase 81 VI. Page H i s t o r i c a l Data 81 P h y s i c a l Findings 92 E v a l u a t i o n of and by the P a t i e n t 106 I n t e r p r e t a t i o n of the X-rays 108 P s y c h o l o g i c a l Results 114 V I I . PRODUCTION OF THE "SUCCESS" FACTOR 125 V I I I . PERFORMANCE OF MULTIPLE CORRELATIONS AND THEIR EVALUATION 135 The C o r r e l a t i o n M a t r i x 135 Assessment o f Examination Methods - What Do They Indicat e ? 140 Mechanical L i m i t a t i o n 141 Pa i n Tolerance and Tenderness 142 P s y c h o l o g i c a l Abnormality 143 N e u r o l o g i c a l D e f i c i t 144 Examiner E r r o r i 146 The R a d i o l o g i c a l V a r i a b l e s - What Information Do They Provide?. 148 IX. DISCUSSION 154 Comparative Assessment o f the F a c t o r s . . . 158 C l i n i c a l A p p l i c a t i o n s 162 Pro s p e c t i v e Studies 163 X. SUMMARY 165 Page CONCLUSIONS 166 FIGURES 169 TABLES 173 BIBLIOGRAPHY 192 APPENDICES INDEX OF FIGURES v i i i . Page 1. The Lumbar Ve r t e b r a 169 2. Mean MMPI p r o f i l e s o f the thicee outcome groups, p i l o t study 170 3. R a d i o l o g i c a l measurements on the l a t e r a l view 171 4. MMPI p r o f i l e s by "success" q u a r t i l e s 172 i x . INDEX OF TABLES Page 1. Biochemical D i s c Changes w i t h Age and Degeneration 173 2. Results o f Discectomy 174 3. Fusion Procedures and t h e i r O r i g i n a t o r s 175 4. Comparative Results o f Reported Fusion Series 176 5. Scoring C r i t e r i a f o r P a t i e n t Grouping, P i l o t Study 177 6. Orthopedic Assessment o f P s y c h o l o g i c a l Parameters 178 7. Measurements o f V e r t e b r a l Body Height 179 8. Measurements o f I n t e r v e r t e b r a l D i s c Height 180 9. Measurements o f P o s t e r i o r J o i n t Subluxation 181 10. Measurements o f R e t r o s p o n d y l o l i s t h e s i s 182 11. Measurements o f I n t e r p e d i c u l a r Distance 183 12. Measurements o f S a g i t t a l Diameter o f V e r t e b r a l Canal....184 13. C o r r e l a t i o n M a t r i x o f "Success" and 239 V a r i a b l e s ...185 14. Factor M a t r i x from " S u c c e s s " - c o r r e l a t i n g V a r i a b l e s ; C o r r e l a t i o n o f Factors A g a i n s t "Succeys" 186 15. D e s c r i p t i o n of the 17 "Suc c e s s " - r e l a t e d F a c t o r s , T h e i r C o r r e l a t i o n w i t h "Success" and the Variance o f "Success" Accounted f o r 187 16. Loadings o f the NASHOLD and HRUBEC D i s a b i l i t y Index 188 17. P s y c h o l o g i c a l Scores on 4 Parameters by Q u a r t i l e Grouping 189 18. C o r r e l a t i o n M a t r i x o f C e r t a i n Orthopedic Examination Methods w i t h the "Success" Index, C e r t a i n P s y c h o l o g i c a l and R a d i o l o g i c a l V a r i a b l e s 190 19. C o r r e l a t i o n M a t r i x of the R a d i o l o g i c a l V a r i a b l e s w i t h the "Success" Index, C e r t a i n P s y c h o l o g i c a l and Mechanical V a r i a b l e s 191 X. ACKNOWLEDGEMENTS * The complexity of this study has entailed the involvement, directly or indirectly, of many people. Without their assistance my work would have been impossible. I mention these particularly, to whom I wish to express my deepest thanks and appreciation for advice, practical assistance, or sustenance: Dr. K.S. Morton and Dr. P.J. Kokan, my sponsors and project supervisors, who initiated and directed my interest. Dr. F.P. Patterson, Professor of Orthopedics, who made possible my year's C l i n i c a l Research Fellowship, which expanded to eighteen months. Franz Wilfling, with whom I exchanged orthopedic ideas and optimism for psychological ideas and a s t a t i s t i c a l foundation. Dr. W.J. Thompson, Head of Orthopedics at Shaughnessy Hospital, for encouragement and provision, with the Department of Veterans Affairs, of f a c i l i t i e s for conducting the study. The Workmen's Compensation Board of British Columbia and the British Columbia Medical Services Foundation, for patient selection information and generous financial support. Dr. S.S. Shim, for experienced advice and help with the prep-aration of the thesis. Mrs. D.A.R. Myers, for stout-hearted and accommodating secretarial assistance throughout the project. x i . Sandra Hodgins, for invaluable and patient help with d i f f i c u l t and unfamiliar computer programs. Pauline, for companionship, intellectual and emotional motivation, and without whom I would not have embarked on the work. 1. INTRODUCTION Low back pain i s a common a f f l i c t i o n , with many possible causes, which can be divided into those which are orthopedic in nature, re-lated to disorder of structure or function of the musculoskeletal structures or non-orthopedic, with pain referred to the back or lower limbs from viscus, vascular or neurological structure. Low back pain i s of great social and economic importance, partic-ularly i n relation to industry, and particularly in patients who reach the stage of requiring surgical intervention in the course of their disease. The problem i s expensive to the patient physically, emotionally, socially and economically and to society due to medical care and time loss. It is helpful to use the concept of low back pain disease, by which we refer the syndrome of symptoms and signs originating from disease or degeneration i n the low back. This w i l l include local features of pain, stiffness and related objective signs and also d i s t a l phenomena such as pain, muscle wasting and weakness, and re-flex and sensory loss, due to radiation, in the case of pain, or interference with the innervation of the caudal part of the body. At the outset, i t is accepted that low back pain may be due to many causes; for example, severe low backache may result from pyelo-nephritis, and is common in genital inflammation whether in the female 2. or male. The Leriche syndrome classically is associated with claudicant buttock and limb pain due to arterial obstruction, tabes dorsalis with shooting pain i n the back and lower limbs; a peptic ulcer often pro-duces mid back pain. Differentiation of these causes may at times be d i f f i c u l t but i s of obvious importance; i t i s the purpose of this paper to consider only the orthopedic causes, specifically those treated by lumbar intervertebral fusion. Low back pain of orthopedic origin may s t i l l arise from various known pain sensitive sources, but i t i s also acknowledged that a given degree of pathologic change can cause a differing pain response in different individuals and the multitude of factors responsible for this has not been f u l l y evaluated. It i s not enough, in the practice of medicine, to approach the human organism solely in terms of tissue response or objective heal-ing of the body. It is only/in terms of function that useful patient assessment i s ever made, and function must be considered i n a l l fields of human endeavour, economic, inter- and intra-personal. It i s par-ticu l a r l y important i n low back pain disease to consider a l l facets of the patient. 3. HYPOTHESES AND PURPOSE OF THE STUDY. I t w i l l be shown i n the review of the l i t e r a t u r e t h a t the present s t a t e o f our knowledge i s l a r g e l y l i m i t e d to known a s s o c i a t i o n s of back p a i n , w i t h no adequate p r o s p e c t i v e study to determine the causes or r i s k f a c t o r s of the c o n d i t i o n . The p r o s p e c t i v e , c o n t r o l l e d study i s the only way t o determine p r e d i c t i v e f a c t o r s or r i s k f a c t o r s , which can give a numerical f i g u r e t o the increased r i s k of a person develop-in g t h i s s o c i a l l y and economically c o s t l y d i s a b i l i t y . However, methods can be evaluated and much o f use obtained i n a problem of such enormity by c o n s i d e r i n g a s m a l l , d i s c r e t e group of p a t i e n t s w i t h the most severe form of the disease. Namely, those whose problems have brought them t o the stage of r e q u i r i n g the o p e r a t i o n o f lumbar i n t e r v e r t e b r a l f u s i o n . The conclusions from t h i s study can then be a p p l i e d both d i r e c t l y to the design of p r o s p e c t i v e s t u d i e s and, w i t h s u i t a b l e m o d i f i c a t i o n s , t o the c l i n i c a l e v a l u a t i o n of pa-t i e n t s w i t h the problem of low back p a i n . By studying the l i t e r a t u r e and from a c e r t a i n amount of c l i n i c a l experience three hypotheses were d e r i v e d . 1J Continued d i s a b i l i t y f o l l o w i n g lumbar i n t e r v e r t e b r a l f u s i o n i s o f m u l t i f a c t o r i a l e t i o l o g y . 2) C e r t a i n p a t i e n t c h a r a c t e r i s t i c s w i l l be i d e n t i f i e d which are l i k e l y to be s p e c i f i c a l l y a s s o c i a t e d w i t h success or f a i l u r e o f the 4. operation. 3) Certain variables w i l l be identified which may prove to be of use as predictor variables in the assessment of low back pain disease. To allow a f u l l understanding of the problem, a 'blunderbuss' approach was selected; to enable useful application of this approach a p i l o t study was performed, the materials, methods and results of which are described separately from the main phase of the study. 5. REVIEW OF THE LITERATURE THE LUMBAR SPINE, IN HEALTH AND DISEASE .Hnbryology and development Anatomy, physiology Vascular supply Innervation Function: biomechanics LOW BACK PAIN DISEASE The Problem of Low Back Pain The Management of Lew Back Pain Intervertebral Fusion 6. THE LUMBAR SPINE IN HEALTH AND DISEASE EMBRYOLOGY AND DEVELOPMENT The v e r t e b r a l u n i t i s commonly regarded as c o n s i s t i n g of two vertebrae and the i n t e r v e n i n g d i s c . V e r t e b r a l development has three 239 stages: b l a s t e m a l , chondrogenous and osseogenous The b l a s t e m a l stage i s under way i n the t h i r d week of i n t r a -u t e r i n e l i f e at which time the notochord has forty-two to f o r t y - f o u r p a i r e d somites, l y i n g on each s i d e , which merge across the m i d l i n e and envelop the notochord as the 'hypochordal bow'. By the f o u r t h 43 239 week ' the somites have d i f f e r e n t i a t e d i n t o the dermatome, myo- • tome and sclerotome. The l a t t e r continues i n the formation of the v e r t e b r a l column and o c c i p u t . Thejsderotomes are separated by the f i s s u r e of von Ebner i n the r e g i o n o f which the c e l l s are more c l o s e l y aggregated. The i n t e r -v e r t e b r a l d i s c i s d e r i v e d from these c e l l s , two-thirds of which o r i g i n a t e from the more caudal segment, together w i t h the v e r t e b r a l end p l a t e d and the annulus f i b r o s u s . Although LUSCHKA and others f e l t t hat the nucleus pulposus was d e r i v e d by degeneration of the annulus f i b r o s u s , KEYES and COMPERE as e a r l y as 1932 p o i n t e d out the notochordal o r i g i n . Although the nucleus pulposus i n the embryo l i e s v e n t r a l to the 7. developing v e r t e b r a l body t h i s i s c o r r e c t e d i n the osseogenous phase. By b i r t h the i n t e r v e r t e b r a l d i s c has achieved i t s f i n a l form w i t h dense, close-packed s p i r a l f i b r e s at the pe r i p h e r y o f the annulus f i b r o s u s , f i b r o c a r t i l a g e c l o s e r to the nucleus which s t i l l c o ntains notochordal c e l l s . At nine weeks a n t e r i o r and p o s t e r i o r i n d e n t a t i o n s appear i n the c a r t i l a g i n o u s v e r t e b r a l body from p e r i o s t e a l v e s s e l s , f o l l o w e d soon 43 by v a s c u l a r i n v a s i o n and c a l c i f i c a t i o n . O s s i f i c a t i o n appears by the 24 f i f t e e n t h week . I f f a i l u r e of f u s i o n p f the i n i t i a l two ( a n t e r i o r and p o s t e r i o r ) 43 o s s i f i c centres occurs, abnormal v e r t e b r a l growth f o l l o w s . O s s i f i -c a t i o n i s seen f i r s t on the lower d o r s a l and upper lumbar r e g i o n s , 43 spreading r a p i d l y upward, l e s s r a p i d l y down . By the t w e n t y - f i f t h week o s s i f i c a t i o n reaches the p e r i p h e r y of the body by which time the growth p l a t e i s e s t a b l i s h e d . The n e u r a l arches are formed by growth from two l a t e r a l primary centres o f o s s i f i c a t i o n . A f u r t h e r separate o s s i f i c a t i o n centre develops i n the c o s t a l processoof the f i r s t lumbar v e r t e b r a , normally j o i n i n g the v e r t e b r a l body by f i v e to s i x years of age, but o c c a s i o n a l l y growing to form a lumbar r i b ^ 3 . At about puberty, a r i n g of bone, a t r a c t i o n apophysis, appears and fuses t o the body at completion o f growth of the v e r t e b r a l column. BISK s t a t e s t h i s to be eighteen to twenty y e a r s ; CARPENTER f e e l s i t i s twenty-two to twenty-five years. BICK emphasises t h a t i t 8. i s from the i n s e r t i o n o f the l o n g i t u d i n a l ligaments and does not con-24 t r i b u t e to growth: i t i s not a true e p i p h y s i s The f u t u r e a n t e r i o r l o n g i t u d i n a l ligament i s seen as e a r l y as seven to nine weeks to be more c l o s e l y attached t o the c a r t i l a g i n o u s v e r t e b r a l bodies w h i l e the p o s t e r i o r l o n g i t u d i n a l band i s f i r m l y attached to the d i s c and not a s s o c i a t e d w i t h the p o s t e r i o r surface of the d i s c . This c l o s e r e l a t i o n s h i p o f the p o s t e r i o r l o n g i t u d i n a l ligament w i t h the d i s c i s of importance when the p a i n pathways are considered. ANATOMY, PHYSIOLOGY The normal lumbar spine c o n s i s t s normally of f i v e vertebrae w i t h a s s o c i a t e d c a r t i l a g i n o u s d i s c s , ligaments, muscles, n e u r a l and vas-c u l a r s t r u c t u r e s . O c c a s i o n a l l y s i x or f o u r vertebrae may be found w i t h v a r y i n g degrees of t r a n s i t i o n a t the lumbosacral l e v e l . According to ROCHE and ROWE i n a s e r i e s 6 f 4,200 skeletons 2.5% of the p o p u l a t i o n 219 have 23 p r e s a c r a l v e r t e b r a l segments, 92.5% have 24 and 5%, 25 A ' t r a n s i t i o n a l ' type of lumbosacral v e r t e b r a i s found i n 10% of 247 people The lumbar v e r t e b r a i s d i s t i n g u i s h e d from the others by i t s g r e a t e r s i z e and by the absence of c o s t a l f a c e t s on the si d e s o f the bodies (Figure 1). "The body i s l a r ^ , wider from s i d e t o si d e than before backwards, 9. and a l i t t l e deeper in front than behind. The vertebral foramen i s triangular in shape, larger than i n the thoracic region but smaller than i n the cervical region. The shape is accounted for by the shortness of the pedicles and the direction of the laminae, which pass backwards and medially. The spinous process projects almost horizontally backwards, i s quadrangular, and is thickened along i t s posterior and inferior borders. The superior articular processes bear articular facets which face medially and backwards, and are gently concave. The posterior border of each process is marked by a rough elevation, termed the mamillary process. The inferior articular processes bear articular facets which are slightly convex and face later a l l y and forwards. The transverse processes are thin and elon-gated, with the exception of those of the f i f t h lumbar vertebra, which are strong and substantial. A small, rough elevation marks the postero-inferior aspect of the root of each transverse process and i s termed the accessory process. " The articular facets are so shaped that, while they permit flexion and extension, they prevent rotation of the lumbar 131 vertebrae." The cortical layer of the vertebral body which is very thin i s pierced, particularly dorsally,by several nutrient foramina. The cranial and caudal surfaces are covered by concave bony end plates, covered with hyaline cartilage. 10. A r t i c u l a t i o n between the vertebrae occurs a n t e r i o r l y by means of the d i s c and p o s t e r i o r l y by means of the p a i r e d , s y n o v i a l f a c e t j o i n t s . The i n t e r v e r t e b r a l d i s c i s d e f i n e d as "the f i b r o c a r t i l a g i n o u s complex t h a t forms the a r t i c u l a t i o n between the bodies of the ver-t e b r a e ^ ^ . The gross anatomy o f the d i s c has been d e s c r i b e d by many a u t h o r s ^ ' . The r a t i o of d i s c : v e r t e b r a l body height i s such t h a t the i n t e r v e r t e b r a l d i s c height i s normally more than 35% 150 of the height of the adjacent body . The r a t i o i s higher at b i r t h 32 and decreases i n i n f a n c y , and adolescence . The d i s c c o n s i s t s of the o u t e r , f i b r o u s annulus f i b r o s u s and the i n n e r v i s c i d f l u i d nucleus pulposus. The nucleus pulposus i s u s u a l l y s i t u a t e d e c c e n t r i c a l l y , being c l o s e r to the p o s t e r i o r margin of the d i s c and demonstrates on cross -s e c t i o n t h a t i t i s under a moderate amount of t e n s i o n . H i s t o l o g i c a l l y i t i s composed of loose c o l l a g e n f i b r i l s i n a g e l a t i n o u s matrix. These have no arrangement i n the centre but approach the v e r t e b r a l chondral p l a t e s at an angle to become embedded there. Fusiform r e t i c u l o c y t e s and vacuolar chondrocytes are i n t e r s p e r s e d i n the matrix. The nucleus has a h i g h water content, maximal at b i r t h when 88% o f i t s volume i s water, decreasing to 80% at eighteen years and 65% at seventy-seven y e a r s ^ " ^ ' " ^ . The d i s c e x h i b i t s a power of water 114 i m b i b i t i o n probably r e l a t e d to the g e l s t r u c t u r e of the nucleus 11. A diurnal variation in i t s water content is thought to account for the age-related diurnal body height variation of 2% at age five 6 2 years to 0.5% at age ninety . The matrix, has thiree constituents beside the i n t e r s t i t i a l f l u i d - glycoproteins, acid mucopolysaccharides and non-collagenous proteins. Other sugars besides the mucopolysaccharides are present in combination with proteins to form glycoproteins, the quantity of which increases with age. The collagen i t s e l f is a glycoprotein, with higher quantities of galactose and glucose than the collagen of other tissues such as skin and tendon"^. The noncollagenous proteins, probably bound to the mucopoly-saccharides, show a change with age. Three different types of 3 protein are identifiable: one i n young children, one appearing in the middle of the second decade of l i f e and a third type after the age of f i f t y that then becomes a major component of the disc t i s -156 „-sue . A . . C The mucopolysaccharides present are chondroitin sulfate A and C, 21 107 keratan sulfate and hyaluronic acid ' . The mucopolysaccharide 170 content i s maximal at age thirty-nine to forty years which i s also the age at which the highest intradisc pressure may be developed by 39 128 f l u i d absorption experiments (and the age of onset of symptoms) The cells showing the greatest a f f i n i t y for the sulfate ion required in synthesis of the mucopolysaccharides (by autoradiography) are the peripheral cells of the nucleus pulposus, which shows a greater meta-12. 246 b b l i c turnover than the annulus . I t i s p o s s i b l e that a constant p o l y m e r i s a t i o n - d e p o l y m e r i s a t i o n process i n the d i s c occurs r e g u l a t i n g 198 the f l u i d components of the nucleus and hence the i n t r a d i s c pressure 1QD The pH of the d i s c i s i n the range 6.8-7.4 . The annulus f i b r o s u s c o n s i s t s o f a c o n c e n t r i c s e r i e s o f f i b r o s u s l a m e l l a e . The f i b r e s are arranged o b l i q u e l y o r s p i r a l l y , encasing the nucleus; the lamellae are t h i n n e r and more c l o s e l y packed poste-r i o r l y . The f i b r e s become longer and more h o r i z o n t a l near the circum-ference o f the d i s c . The t r a c t i o n apophysis provides the attachment f o r the annulus f i b r o s u s and the a s s o c i a t e d l o n g i t u d i n a l ligaments. The l a r g e s t e x t e r n a l f i b r e s penetrate the bony r i n g as Sharpey's f i b r e s ; the outermost f i b r e s blend w i t h the periosteum and l o n g i t u -d i n a l ligaments. The annulus shows a s m a l l r e d u c t i o n of c o l l a g e n content r e l a t i v e 198 t o the 3-protein content w i t h age . I t a l s o undergoes a r e d u c t i o n 212 i n water content from 78% at b i r t h to 70% at t h i r t y years . Poly-saccharides i n the annulus are c h o n d r o i t i n s u l f a t e and keraton s u l -f a t e , and NAYLOR found s s i a l i c a c i d on the p e r i p h e r y , p o s s i b l y an 198 i n d i c a t i o n o f greater r i g i d i t y at t h a t s i t e . DAVIDSON and WOODHALL 58 found t h a t changes i n the c h o n d r o i t i n s u l f a t e were ag e - r e l a t e d , w h i l e NAYLOR s t a t e d the c h o n d r o i t i n s u l f a t e f r a c t i o n t o be v i r t u a l l y unchanged w i t h aging, although he found a d e f i n i t e decrease i n keratan 1 4 r . 198 s u l f a t e 13. Electron microscopy shows the annulus to consist of collagen 107 f i b r i l s arranged i n sheets showing biaxial orientation . The nucleii of the annular cells are frequently pyknotic or absent and fine 198 collagen f i b r i l s are present in the cytoplasm . Granular material at the end of the biconvex cells appear to be responsible for collagen production. The chondrocyte-like cells of the cartilaginous segment of the annulus have been shown by SOUTERaand TAYLOR to be metaboli-cally active while the fibroblasts of the outer one-third of the annulus show a much lower S*^  tagged sodium sulfate u p t a k e T h e persistence of this isotope was shown by these authors to be greater in the annulus than the nucleus. DEGENERATIVE DISEASE OF THE INTERVERTEBRAL JOINT. The age-related changes in the disc have been described and they overlap to a great extent with the pathological changes. NAYLOR cate-198 gorises these changes as in Table l . The structural changes re-sulting have been described by a multitude of authors'^' 118, 218, 234, 255, 280 ™ . , . ' ' ' ' . The nucleus loses i t s gelatinous quality, becoming fibrous and firm while the annular lamellae lose height posteriorly by arching backwards and packing together. This happens 218 by the beginning of the third decade . The nucleus becomes firm and viscous, retaining i t s volume i n i t i a l l y but losing i t s mobility because of fibrous anchoring to the cartilaginous end plate. In the fourth decade, small peripheral clefts appear between the layers of 14. the annulus, p a r t i c u l a r l y p o s t e r i o r l y and p o s t e r o l a t e r a l ! / , which may l a t e r coalesce and form r a d i a l t e a r s , extending t o the p o s t e r i o r l o n g i t u d i n a l ligament. S o f t e n i n g o f the annular lamellae precedes the c l e f t formation. From age s i x t y onwards, p r o g r e s s i v e f i b r o u s r e -placement appears to occur, w i t h gradual a p p o s i t i o n of the vertebrae. P o s t e r i o r displacement of the nucleus may be sudden or a c h r o n i c process, u s u a l l y the l a t t e r ^ . Complete sequestra may form w i t h sub-sequent i n v a s i o n of p a r t of the d i s c by g r a n u l a t i o n t i s s u e . Nerve root damage may r e s u l t by impingement of n u c l e a r m a t e r i a l or a r t i c -u l a r f a c e t s , which g r a d u a l l y sublux as the d i s c narrows. Osteo-a r t h r i t i s of the p o s t e r i o r j o i n t s may supervene, p o s s i b l y due to mal-85 alignment , w i t h the a s s o c i a t e d c a r t i l a g i n o u s , s y n o v i a l and capsular changes; these changes f o l l o w the d i s c d e g e n e r a t i o n " ^ . I n the l a t e r stages of d i s c degeneration, bony outgrowths from the margin of the v e r t e b r a l body may take v a r i o u s c o n f i g u r a t i o n s . MACNAB e t a l d e s c r i b e d f i v e types, suggesting c a u s a l mechanisms i n -volved"'"^. I n s t a b i l i t y (abnormal m o b i l i t y at an i n t e r v e r t e b r a l j o i n t ) was f e l t t o be a s s o c i a t e d w i t h the " t r a c t i o n spur", a r i s i n g a n t e r i o r -l y from the v e r t i c a l surface o f the v e r t e b r a l body about 3-4 mm from the i n t e r v e r t e b r a l border and the "bubble spondylophyte", seen pos-t e r i o r l y i n the lumbar r e g i o n . They found no constant r e l a t i o n s h i p of osteophyte p a t t e r n w i t h p o s t e r i o r j o i n t a r t h r i t i s , however. Although the p a t h o l o g i c a l changes ( s i m p l i f i e d here) are w e l l 15. documented, the underlying causes are controversial. In an exhaustive review of the morphological and biochemical knowledge of disc prolapse TAYLOR and AKESON f e l t the f i e l d of chemical and physical interactions 255 to be largely unexplored . They suggested physical forces are par-amount in conditioning the behaviour of the fibrocartilaginous c e l l and in producing changes in the extracellular components; BROWN feels that mismatching of demands made on the disc and i t s physical capa-36 b i l i t i e s accelerate the degenerative process . NAYLOR, on the other hand, suggested that autoimmune processes might be responsible as an 198 i n i t i a t i n g mechanism , the f e a s i b i l i t y of which was demonstrated 27 by BOBECHKO and HIRSCH . A multifactorial mechanism can be envisaged 279 with the interplay of several f actors, 7, -. Abnormal physical loading due to loss of abdominal muscle power with age or increased resting muscle tension, added to our erect posture might i n i t i a t e discal damage, with release of proteinaceous-contents and autoimmune re-action . The disease process is thus outlined: the relationship i t bears to pain is discussed later. THE VASCULAR SUPPLY OF THE REGION. The paired lumbar arteries, in series with the posterior inter-costal arteries, represent persistent intersegmental somatic branches 16. 131 of the a o r t a i n the embryo . Four or f i v e i n number, they run l a t -e r a l l y and backwards on the bodies o f the lumbar v e r t e b r a e , deep to the sympathetic t r u n k s , t o reach the i n t e r v a l s between the adjacent transverse processes. They pass behind the psoas muscle and the lumbar plexus and pass i n t o the abdominal w a l l , the upper three a r t e r i e s running behind the quadratus lumborum and the l a s t u s u a l l y i n f r o n t . Each gives o f f a d o r s a l ramus which passes backwards between the 78 transverse processes, an a n t e r o l a t e r a l intraosseous branch and muscular branches to the psoas. The d o r s a l branch d i v i d e s almost immediately i n t o s p i n a l and muscular branches. The d i v i s i o n s o f the s p i n a l branch are: (1) A p o s t - c e n t r a l branch to the v e r t e b r a l arches and l i g a -mentum flavum (2) A n t e r i o r and p o s t e r i o r r a d i c u l a r branches to nerve r o o t s , cauda equina and meninges (3) A dorso-medial branch supplying the p o s t e r i o r l o n g i t u d i n a l ligament and p o s t e r i o r aspect of the v e r t e b r a l body (4) Muscular b r a n c h e s ^ ' ^ The terminology of these v e s s e l s i s somewhat confusing. MACNAB and BALL performed i n j e c t i o n s t u d i e s and found the f o l l o w i n g branches: (1) The a n t e r i o r t r ansverse a r t e r y , from the main trunk o f the lumbar a r t e r y , and l y i n g on the a n t e r i o r s urface o f the transverse 17. process. (2) The intertransverse artery arising at the point of division of the dorsal ramus and passing laterally in the middle layer of the lumbar fascia about midway between adjacent transverse processes. (3) The inferior articular artery given off by the communicating artery above or the interarticular branch below. It curves around the inferolateral aspect of the joints and pierces the intermediate layer of the lumbar fascia. 778 (4) The foraminal arteries (also described by WILEY and TRUETA A 10 and AMATO and BOMBELLI ). MACNAB and DALL describe two such branches These supply the posterior portions of the vertebral body and the structures in the neutral canal. (5) The communicating artery passes across the posterior aspect of the transverse process from one segment to the next segment below, where i t forms an anastomosis. (6) The superior articular arteries, usually two in number, passing around the superolateral aspect of the posterior joints. The vertebral bodies themselves are supplied by minute vessels 278 anteriorly from the segmental (lumbar) arteries . The posterior spinal branch (presumably the dorsomedial branch of FERGUSON and EPSTEIN) divides into an ascending and descending branch anastomosing, below, and to the other side. This posterior blood supply has been shown in the rabbit to develop just before birth, although at no time does i t invade the disc, which was seen to have only a blood supply 4 to its boundaries . 18. The disc i s avascular but there i s disagreement over the avas-c u l a r i t y of the disc during development. DE PALMA and ROTHMAN state that the disc i s supplied by small vessels through the cartilaginous end plate up to the age of eight y e a r s 6 1 . SCHMORL and JUNGHANNS give evidence that a vascular supply i s seen i n the outer, fibrous part only during embryonic development, while no connections e x i s t with 234 the vessels supplying the vertebral bodies . The more abundant de-velopment of vessels i n the dorsolateral part of the disc i s thought to account for the proneness to c l e f t and tear formations i n th i s part. A l l vessels are completely obliterated by the fourth year of l i f e . PARKE and SCHIFF say that the vessels from the vertebral body never actually penetrate the disc-destined material. The venous drainage of the area, i s from the large valveless 278 venous channel draining the vertebral body v i a the nutrient foramen to the spinal and paraspinal plexus of Batson which shows free 18 communications with p e l v i c , lumbar, thoracic and i n t r a c r a n i a l vessels The importance of the supply of the spine l i e s i n four sources: (1) The s u s c e p t i b i l i t y to metastatic i n f e c t i o n or tumor, although there are arguments f o r both the a r t e r i a l and venous mechanisms here. (2) The p o s s i b i l i t y of damage to the vessels at the time of surgery with ischemia of the cauda equina or vertebrae, potential cause of d i s c i t i s of nervous les i o n . (3) As a channel for the transmission of pressure changes to the 19. spinal canal - a negative pressure being present in the epidural space normally due to transmission of the intrathoracic pressure. (4) In the possibility of bleeding at the time of surgery, which may be of sufficient quantity to require replacement or of importance in the formation of adhesion. THE NERVE SUPPLY OF THE REGION. The dorsal (posterior) primary rami of the spinal nerves supply a serially segmented territory, do not extend to the muscle of the limbs and are not involved in plexuses, but supply the skin and 97 "native" deep muscles of the back medial to the angles of the ribs At each lumbar level the posterior ramus splits into a medial and lat-204 eral branch after passing through the intertransverse ligament . The lateral branch passes through the erector spinae muscles into lon-gissimus and iliocostalis, progressing to the lateral border of the latter. It pierces the posterior lamina of the lumbar fascia and those of L l , L2 and L3 cross the i l i a c crest to supply the skin of 97 221 the buttock as far as the greater trochanter of the femur ' The medial branch of the posterior ramus descends posterior to the transverse process of the vertebra below lying in a groove formed by the junction of the transverse process and the superior articular process. At the inferior margin of the superior process there is a small notch through which the nerve passes, giving a small 20. twig to the inferior part of the articular capsule. It continues in-f e r i o r l y , ramifying i n the dorsal muscles and anastomosing with nerves of other levels. It l i e s next to the lamina and follows the inferior border of the spinous process posteriorly almost to the midline 2 0 4. PEDERSEN et al f e l t that pain fibres supplied the facets and surroundings t i s s u e s 2 0 4 but SCHMORL and JUNGHANNS quoting the work of HIRSCH and others were less certain that pain could originate from 234 this source . JACKSON et a l demonstrated several different types 130 of fibre and nerve ending in the fibrous facet capsule 204 734 The sinU3vertebral nerve, named by VON LUSCHKA in 1850 ' is f e l t to be the major source of supply to the periphery of the intervertebral d i s c 6 1 , 2 0 4 ' 2 3 4 . It is also known as the ramus re-234 221 currens and the recurrent meningeal nerve . It arises at each level from i t s spinal nerve irear or with the ramus communicans then returns into the spinal canal through the intervertebral foramen, often lying against the posterolateral border of the disc; i t then curves ifitephalad around the base of the pedicle and proceeds towards the midline of the posterior longitudinal ligament, giving filaments to the ligament, periosteum, blood vessels of the epidural space, 204 and dura mater. It contains myelinated fibres of varying size The disc i t s e l f does not contain nervous elements although the presence of nerve endings in the outer annular layers is debated (PARKE-SCHIFF). The hypothesis that nerve fibres may grow into the 130 ruptured dischwith granulation tissue has not been substantiated .21. However, a nerve supply closely associated with the vascular sinusoids has been seen in the cartilaginous end plates of the vertebrae in the 130 fetus and infant . Adult supraspinous and interspinous ligaments show very few nerve endings. Ligamenta flava, showing the presence of a few nerve elements in the fetus and newborn, have only a few 130 nerves in the loose areolar tissue on the surface in the adult Pain perception from the lumbar structures is discussed further in the section 'The Problem of Low Back Pain'. FUNCTION OF THE SPINE. It i s necessary to precede a discussion of pain arid surgery of the lumbar spine with a description of i t s physical properties. For this purpose, a vertebral unit i s considered as the intervertebral disc and contiguous parts of the vertebral bodies, together with their posterior arches; the intervertebral joint consists of the disc and facet joints, with appropriate ligaments. It w i l l be impossible to do justice to the literature dealing with the mechanical properties of the spine - the subject has been thoroughly investigated by many workers. The spine'as a whole can be considered as an elastic rod"^' As such, i t has a c r i t i c a l vertical load above which i t w i l l buckle -in the unsupported spine this i s about 2 kg, while i f laterally supported at both ends the value is about 33 kg, approximating the 22. weight of the trunk. Stabilisation of this rod is necessary: ASMUSSEN and KLAUSEN suggested the model of a segmented pole stabi-13 lised by guy-wires, represented by the muscles of the trunk . The disc acts to distribute weight over a large surface of the vertebral body during bending motions and as a shock-absorber^1' 1^)1. The stiffness of the disc is greater i n compression than in t e n s i o n 1 ^ and i t is f e l t by ROLANDER that the greatest elastic efficiencycof the disc is reached i n adulthood, when the nucleus has disappeared 220 as an entity . This may be related to loss of usefulness as a shock-absorber, however. The disc appears to be the strongest part of the vertebral unit -in symmetrical vertical loading, the vertebral end-plates fracture 220 before the disc w i l l rupture . BARTELINK's figure of average yield strength of the disc of 710 lbs. was based on specimens from subjects aged saixty to eighty years, and possibly not subjected to symmetrical loading, so that disc rupture could precede vertebral damage. However, this possibly approximates the in vivo situation more closely than that of ROLANDER. The forces acting on the lumbar vertebral unit have been care-f u l l y calculated and evaluated. BRADFORD and SPURLING calculated that a force of 1500 lbs might be exerted on the disc in the individual l i f t i n g 100 lbs; this i s clearly impossible i n view of the known yield strengths 3 1. NACHEMSON and MORRIS demonstrated the intradiscal 23. pressure to be 10-15 kg/sq. cm i n the lower lumbar discs in the si t t i n g 193 position, about 30% lower when standing and 50% lower when reclining The actual load on the disc i s about 82 kp when standing and 113 kp when si t t i n g without support, l i f t i n g 20 kg with bent back and extended 191 knees increases the load by about 300% . These figures were obtained by use of a needle pressure transducer although needle puncture may cause disc rupture Within the normal limits of motion, s t a b i l i t y of the lumbar spine i s provided by the muscles acting across i t , which have been studied photographically, radiographically arid electromyographically. The muscles can be divided into four groups: a) erector spinae b) superficial muscles c) paravertebral muscles (psoas major and minor, quadratus 133 lumborum) d) abdominal muscles The erector spinae has two compartments i n the lumbar region - the deep, medial multifidus compartment containing the mult i f i d i and small interspinal, rotator and medial intertransverse muscles; the lateral border does not extend lateral to the transverse processes. The lateral or sacrospinal compartment contains the common origin of 134 the longissimus and i l i o c o s t a l i s muscles . These muscles have been shown to have separate functions, even different functions at differ-ent l e v e l s 6 6 . The psoas and""sacrospinal" muscles were shown by 24. 133 JONSSON to be antagonistic , yet NACHEMSON demonstrated the extensor 188 189 function of the psoas i n stabilisation of the spine ' , attached to the transverse processes behind the centre of motion of the verte-49 206 bral unit ' . He demonstrated the importance of the psoas as a stabil i s e r , and stated that i t probably is responsible for the excess load on the disc unaccounted for by the weight of the body alone. The erectores spinae muscles show varying activity, and often 80 175 act as resistors of gravity rather than initiators of motion ' This activity ceases on f u l l flexion at which time the ligaments appear to take the load, except that even i n this position coughing w i l l produce erector spinae activity as i t does i n a l l trunk muscles. There i s normally a 'silent period' between activity of abdominal and back muscles on flexion-extension, but there is an overlap i n the 172 presence of low back pain . This overlapping was not found in those with fusion for TB., i f the pelvis i s held immobile, or i n experi-mentally produced low back pain. Instability of the lumbar spine was 172 held responsible. BARTELINK suggested the role of the abdominal muscles i n re-17 lieving the load on the spine during l i f t i n g . This has been con-firmed by data showing that the force on the lumbosacral disc is about 30% less than would be present without the support of intra-cavity pressure of the t r u n k . in fact, the application of external abdominal pressure by an air-pressure corset causes no overall change i n the intraabdominal pressure on l i f t i n g , a l l o w i n g diminished 176 237 EMG a c t i v i t y o f the abdominal muscles ' Perhaps t h i s represents " d i s c o v e r y of what everyone a l r e a d y 159 knows" but i t i s v a l u a b l e knowledge i n the study of the p a t i e n t 191 193 w i t h low back p a i n , s t i l l u s u a l l y a s c r i b e d t o mechanical causes ' Symmetrical a r t i c u l a r f a c e t s appear necessary f o r p r o t e c t i o n o f the i n t e r v e r t e b r a l j o i n t by l i m i t a t i o n of range of motion and add 75 76 253 t o i t s o v e r a l l t o r s i o n a l s t r e n g t h ' as w e l l as c o n t r i b u t i n g to both the extension and t o r s i o n a l s t i f f n e s s o f the lumbar i n t e r -v e r t e b r a l j o i n t s 1 ^ . This i s p a r t l y by m a i n t a i n i n g the a x i a l i n s t a n t centre of r o t a t i o n i n i t s normal p o s i t i o n i n the r e g i o n of the pos-49 t e r i o r p a r t o f the nucleus ; asymmetry o f the a r t i c u l a r processes leads to asymmetrical d i s c degeneration, but t h i s i s probably r e -l a t e d t o shear f o r c e changes r a t h e r than a c t u a l changes i n range of 163 a x i a l r o t a t i o n . I n t a c t p o s t e r i o r elements are apparently necessary f o r l i m i t a t i o n o f the d i f f e r e n t planes of motion: the spinous process being important i n e x t e n s i o n , the ligamentum flavum; f l e x i o n and ex-273 t e n s i o n The p a t t e r n of degeneration i s a l s o a f f e c t e d by other geometric 77 v a r i a t i o n s i n the lumbar spine . The development of p o s t e r o l a t e r a l f i s s u r i n g i s seen more i n d i s c s w i t h f l a t t e n e d p o s t e r i o r s u r f a c e s , m i d l i n e ruptures i n these w i t h a rounded p o s t e r i o r s u r f a c e . Abnormal-i t y on discography on autopsy specimens i s more commonly seen at the L4-5 l e v e l i n l o r d o t i c spines and L5S1 i n f l a t t e r s p i n e s , although 26. the amount of l o r d o s i s was not r e l a t e d t o age and sex. Increased i n -c l i n a t i o n o f the lumbosacral j o i n t appeared to p r o t e c t i t against 77 annular damage ; some authors, however, i m p l i c a t e i n c r e a s e d lumbo-s a c r a l angle as a d e f i n i t e cause of low back p a i n 4 0 . Bending x-rays show l e s s m o b i l i t y at these l e v e l s i n those w i t h low back p a i n 1 6 6 r e l a t e d p r i m a r i l y to age of sub j e c t and recent onset of symptoms, a l -though s e v e r a l authors have suggested i t i s of s t r u c t u r a l e t i o l o g y . HIRSCH and LEWIN found evidence of o s t e o a r t h r i t i s of the s y n o v i a l j o i n t s at the lumbosacral l e v e l when the range of motion was de-122 creased, although d i s c degeneration d i d not a f f e c t f a c e t e x c u r s i o n The s t r e n g t h o f the a n t e r i o r and p o s t e r i o r l o n g i t u d i n a l l i g a -ments i s reduced i n d e g e n e r a t i o n 2 6 0 . The normal m o b i l i t y o f the lumbar s p i n e , however, i s sometimes not a c c u r a t e l y documented 4 0. CLAYSON e t a l found the mean range of motion i n the s a g i t t a l plane i n the lumbar sp i n e s o f normal young women t o vary from 12.6 degrees at the L l - 2 l e v e l t o 18,7 degrees 45 at the L5S1 l e v e l ; ALLBROOK found the motion t o be g r e a t e s t at the L4-5 l e v e l ( i n a group predominantly c o n s i s t i n g of Negro males). TROUP, HOOD, and CHAPMAN used two methods t o assess o v e r a l l s a g i t t a l m o b i l i t y of the lumbar spine i n young males and females, t h e i r sur-face marker measurement showing a h i g h degree of c o r r e l a t i o n w i t h 2 63 r a d i o g r a p h i c techniques. The o v e r a l l range of motion f o r a l a r g e s e r i e s of young males and females was 80 degrees and 81 degrees r e s p e c t i v e l y ; the males showed a negative c o r r e l a t i o n w i t h age, 27. unlike the females (within a narrow age range). This figure was a l i t t l e less than CLAYSON et al's 92 degrees. TROUP and his colleagues mentioned that individual variance from day to day or even minute to minute is considerable; they also demonstrated a correlation between lumbar sagittal mobility and femur/trunk angle, of unknown signif-icance. LINDBLOM, in a myelographic study of 449 patients, found disc herniation to be more common at the L5S1 level in females than males and moie common at the L4-5 level in males than females^? Although he related degeneration patterns to direction and degree of spinal cur-vature, i t may be that his figures reveal the effects of differential motion at these levels in the two sexes. THOMAS and RAU f e l t flattening of the lumbar lordosis to be a protective feature in low back pain, 257 produced by relaxation of the deep short extensor muscles . Axial rotation between L l and L5 has a maximum value of about 10 degrees 99 overall , while the lumbosacral joint shows about 6 degrees of 163 rotation , the latter always being associated with flexion of L5 on SI. High torque values are l i k e l y to be associated with sudden twisting motions of the trunk in the axial direction: investigation into these continues1''". MOLL and WRIGHT, in a study correlating a c l i n i c a l method of assessing motion with radiographic motion, found that mean mobility increased i n i t i a l l y from the fifteen to twenty-fourdecade to the twenty-five to thirty-four year decade, with later progressive 28. decrease up to 50%. Mobility i n the male was found to be greater than in the female, except on lateral flexion. (Axial rotation was excluded from this study.) Determination of the instant centre of motion or centroid may soon find greater c l i n i c a l application. It has been shown to be 206 well-localized on flexion/extension in the normal subject, lying within a discrete zone for each level but l i k e l y to be more widely scattered i n cases of intervertebral joint pathology. This normally allows the facets to slide over each other but in degeneration forces 85 them together . Thus i t can be seen how biomechanical considerations are l i k e l y to be of c l i n i c a l usefulness, though they have yet to be correlated with the c l i n i c a l presence of low back pain - for example, the differences i n abdominal and back muscle strength i n those with low back pain and those without are minimal and limited to certain narrowly defined subgroups according to NACHEMSON and LINDH, con-trary to the hypotheses of previous writers quoted by them. The application of biomechanical methods to the operation of spinal fusion w i l l be discussed in that section. 29 THE PROBLEM OF LOW BACK PAIN "Backache may be a result of a frustrated, aggressive masculine drive or a substituted sensuous experience backache can and does at times represent a shift of sexual sensuousness to the back in the form of pain. We have been able to demonstrate c l i n i c a l l y that with therapy when the focus of sensuous experience can be moved out of the back to where i t belongs, in the pelvis, the backache disappears'^^. Fortunately, our knowledge of the problem of low back pain in industry i s greater than the above quotation would suggest, although i t is from an article in 1967 entitled, "Industrial Backache". How-ever, the limitations of our knowledge are also f a i r l y clear. Because the greatest socioeconomic impact of low back pain i s in the industrial population, with consequences costly both to the workman and his employer, i t is here that the problem has been most studied, even by special epidemiological teams such as the Industrial Survey Unit (LS.U.) of the Medical Research Council of Great Britain. Figures giving an idea of the magnitude of the problem may be ex-pressed as prevalence (the number of cases of the disease existing for a given area or at a given time) or incidence (the number of cases arising for a given number at risk i n a particular time). Some series are not s t r i c t l y comparable partly because these two different 30. figures are used and partly as some studies are based on symptomatic findings and others are based on radiological studies which are per-haps less important from the patient's and physician's standpoint. CAILLIET has said that the low back syndrome affects 801 of 40 members of the human race . HULT found that of 1200 males aged 25 to 59 years in varying occupations occasional low back pain was pres-ent in 60% 1 2 8, while HIRSCH, JONSSON and LEWIN found that 50% of the population of 692 females aged 15 to 71 years had occasional back pain increasing from 18% in the junior groups to almost 70% by age 121 45 to 54, with no increase beyond this age . HODGKIN in a study considering four different general practices in England found the yearly rate of reported backache per 1000 males to be 78.4 in three 123 urban practices and 20 in one rural practice , but i t s t i l l should be remembered that many patients have been shown to treat themselves 7 rather than consult their medical practitioner . Figures from the I.S.U. showed that of 237 men classified as having 'disc disease' 48% treated themselves and did not report their d i f f i c u l t y to their gen-eral practitioner. The urban figures for females were slightly higher. This suggests that urban conditions tend to increase the complaint of backache but compensation is not a major motive as comparatively few 7 of the women were eligible for 'sick pay' . BENN and WOOD have pointed out the d i f f i c u l t y according to the International Classification of Disease i n obtaining reliable figures 31. 20 for dis a b i l i t y rates . This is because of the vague nature of the terminology involved. They found that in England "lumbago" or "pain in the back" led to a mean duration of 19 to 21 days off work for males in 1969. Radiation indicated by "sciatica", led to 36 days ab-sence and "displacement of the disc" to 53 days. It was impossible to similarly evaluate backache contained within the category of 20 "osteoarthritis" . Difficulty i s also experienced in relating low back symptoms to disc degeneration. LAWRENCE, in a study of 713 males and 809 females aged 35 and over, found that 11% of the males and 19% 152 of the females had back-hip-sciatica pain at the time of the survey In addition 40% of the males and 33% of the females gave a history of pain in the past only. The pain was most commonly localised in the low back radiating in a third of the cases to the hip or the leg. It was episodic i n 57%, occurred as a single attack in 29% and was chronic in 14%. HULT estimated that in Sweden approximately 2 million working 128 days are lost yearly by men because of back trouble . Other Swedish figures show spinal disorders account for 7.3-20% of a l l days lost from work due to il l n e s s , second only to upper respiratory infections 126 as a cause of time loss and in one series to psychiatric disorders ROWE, in a study from Kodak also found that low back disa b i l i t y was the top item i n compensation patients and ranked second only to 224 upper respiratory infections i n payment of sick benefits . In a ten-year-period, 35% of the male sedentary workers and 47% of the male 32. heavy handlers made v i s i t s to the medical department for low back pain. The time loss due to back pain in the entire division was four hours per man per year. Seventy per cent of the patients were in their thirties and forties and only 15% could relate low back pain to trauma, while another 20% could make a possible connection to some unaccustomed activity. Eighty-five per cent of the early attacks consisted of acute, non-specific low back pain and bore none of the c l i n i c a l characteristics to allow discogenic diagnosis. STEINER, medical director of General Motors, found at one plant with 5,124 employees that 3,299 visited the medical department during 1967 at 250 least once for some complaint . Twenty-two per cent of these were for back complaints. The compensation aspect i s of importance. MCGILL stated that workers off work with back complaints for more than six months found 182 only a 50% possibility of ever returning to work . Over a year this dropped to 25%, and over two years almost n i l . He mentioned that in Washington State the average claim costs more than other forms of claims, constituting 5% of the total number of claims but 24% of the total days lost. GURDJIAN reported that in Michigan in 1966 the back accounted for 9400 of 44,000 cases of d i s a b i l i t y , the major single area of the body involved 1^. He stated that figures from other states were reportedly comparable. The experience in British Columbia is that the Workmen's Compensation Board processes about 30,000 claims annual-169 l y , and of these 6000 are back cases . In 1971 4469 were formally 33. admitted to the Workmen's Compensation Board Outpatients Clinic in 169 Vancouver; 35% of these had back injuries In the I.S.U. studies 46% of those with "disc disease" had had 7 at least one spell of absence lasting three weeks . The overall sick-ness absence rate for these patients was 143 weeks per 100 men per year. It is estimated that of the cases seen at the medical department of CP. Air in Vancouver approximately 3-5% are back related com-. - + 113 plaints BOND reported that 2% of alleemployees have a compensable back 28 injury each year; many are recurrent in the same person . Back in-juries were also the subject of a study by SCHEIN from the New York Fire Department. In the period under study there were 1,687 service-connected injuries from a force of 11,000 men. Spinal injuries com-prised 12.5% of the total and 19.51 of significant injuries with four-232 fi f t h s of these being related to the lumbosacral region KOSIAK, AURELIUS and HARTFIEL found that in the 3M plant at St. Paul claims for back injuries constituted about 20% of a l l compensation 146 147 claims, averaging (up to 1960) 20.16 days per l©ist-time injury ' TROUP et a l found that in Britain back injuries accounted for about 20 million person-days in time loss and JL87.5 million in economic cost annually ; however, the overall monetary costs are d i f f i c u l t to evaluate, in the case of a compensable patient with medical costs, 34. time los§ benefits and loss of trained manpower and especially i n the chronic absenteeism of the chronic low back pain sufferer. The e s t i -mated annual cost to Blue Shield, Blue Cross and the Workmen's Com-pensation Board of medical care alone for neckache and backache based on the year 1967 in the State of Michigan was estimated by HAYES to 11? ?Rd be $53,000.00 . WILSON estimated that non-skeletal back injuries had cost nearly 25 million dollars in New York State in one year. In-flation may have added to these costs. The cost to insurance companies of the f i r s t back operation of any patient is estimated to be approx-82 imately $18,000 . Approximate figures for Canadian Pacific Air show 113 $2,300,000 lost because of sick leaves i n 1971 ; i t is not possible to say what might be a r e a l i s t i c estimate for back-related complaints. Other intangible losses are inestimable, such as decrease in produc-tivityyby reduction in efficiency of the working team, a relatively more1 important factor i n the case of the s k i l l e d worker. There i s a remarkable lack of figures on job in s t a b i l i t y related to back pain but ANDERSON, DUTHIE and MOODY found that in miners, disc disease was the rheumatic complaint most l i k e l y to cause a man 9 to change his job -. Effects on home l i f e , social activity, sexual activity^, spouses and children cannot be quantitated; the emphasis on the industrial aspect is because i t is the easiest to study and probably w i l l be the most sensitive index of success of any preventive program. 35. THE CAUSES OF MUSCULOSKELETAL BACK PAIN SEX: The differences between male and female have already been described; incidence of symptoms seems to be approximately equal i n the two groups. ETHNIC: BREMNER, LAWRENCE and MIALL found the same prevalence 33 of lumbar disc disease i n Jamaicans arid Caucasians . FAHRNI and TRUEMAN f e l t that although the hypertrophic changes on x-ray were much the same i n a pri m i t i v e population i n West Central India as i n reported Caucasian populations, disc narrowing was found to be s l i g h t -73 l y less common . No symptomatic comparison was made. GOFTON, LAWRENCE, BENNETT affd BURCH demonstrated a high prevalence of ankylosing spondy-91 l i t i s manifested as s a c r o i l i i t i s i n members of the Haida Indians This was also seen i n f i r s t degree male re l a t i v e s of patients with ankylosing spondylitis. BERRY described genetically determined disc lesions i n the p i n t a i l mouse (a mutation)' and suggested a s i m i l a r 22 factor might be operative i n humans CONGENITAL AND OTHER ANOMALIES OF STRUCTURE: There i s some controversy regarding the role played by lumbar spine anomalies: WILTSE comments on the lack of experimental evidence f o r the discussion on the effe c t of the common anomalies of the lumbar spine upon low back pain i n his summary of the available 288 material, and infers a prospective study i s required . He considers 36. the more common anomalies. Defect of the pars intera'Tticularis. A person with pars defects 128 1^6 28Q is about 25% more l i k e l y to have back pain than one without ' ' It is also f e l t that disc degeneration occurs more often in the presence of this defect, whether i t i s unilateral or bil a t e r a l . Tropism. Asymmetry of the posterior joints is f e l t particularly by FARFAN and his colleagues to be associated with increased wear of 75 76 77 the disc arid low back pain ' ' , due to inadequacy of their stabilising effect. Scoliosis. This does not cause an increase in the incidence of 47 126 128 low back pain ' ' , although there may be increased disc de-generation at the apex of the curve. Increased lumbar lordosis. Epidemiologically, this is not f e l t 126 128 247 to increase the incidence of low back pain ' ' , although 77 disc degeneration may be enhanced at specific levels Lumbosacral t i l t . There is no evidence for the increased in-280 cidence of low back pain claimed by some ; a t i l t shown to be due to one short leg ( i f not excessively short) has been shown not to be 4Z 1 U 1 • 1 2 6 > 1 2 8 a cause of low back pain ' 247 Spina bifida. SPLITHOFF rejected this as a cause of low back pain , while FULLENLOVE and WILLIAMS showed i t to be more common in their 87 asymptomatic group but occasionally spina bifida occulta of the f i r s t sacral vertebra, associated with a long, hook-like-L5 spinous 37. process may cause low back pain and require surgical treatment*^. Transitional vertebrae.. It is probable that the presence of an abnormal number of lumbar vertebrae or a transitional lumbosacral vertebra is not associated with increased low back pain^ 3^' ^'' but specific features associated with i t , such as involvement of one transverse process in the sacroiliac articulation probably can be . j. ,280 painful Spinal stenosis.. This i s p a r t i a l l y developmental, par t i a l l y 132 231 266 acquired ' ' . Implicated in certaiiL-cases of low back pain, normal data regarding sagittal dimensions of the spinal canal have only recently been published 1 1^. In spite of conflicting evidence, s t r i c t pre-employment exclusion screening by x-ray i s held by some to be of value. SBHEIN stated that any of the following conditions would lead to rejection of candidates for employment in the New York City Fire Department: disc degeneration, failure of fusion of the posterior elements, unilateral transitional lumbosacral vertebrae, spondylolisthesis, old compression fracture, 232 and apophyseal anomaly, severe scoliosis and osteoarthrosis . His rejection rate must be at least that of MCGILL, who f e l t that reduced costs from back illness in a large industrial company j u s t i f i e d a 10% 182 rejection rate . Rejection rates of 25% or more have been suggest-ed ' . Other authors, however, are less enthusiastic about pre-1 OO 1 JA employment screenings ' . LA ROCCA and MACNAB found that no 38. developmental, degenerative change or combination of these had pre-dictive value when applied to the ind i v i d u a l 1 ^ 0 . Most figures indi-cating that these anomalies are significant are retrospective, un-controlled, and part of an overall program for low back pain disease prophylaxis and c a r e 1 4 6 , so that there is no way of determining which 264 health care measures were the c r i t i c a l ones . Prospective, con-trolled t r i a l s are essential, which w i l l l i k e l y be indtastrially based 2 6 4' 2 9 0. DEGENERATIVE: The relation of incidence of back symptoms to age leave l i t t l e doubt that degeneration of the disc is important as a cause. There is a peak age of onset of symptoms, f e l t by BROWN to be due to mismatching of the physical demands made on the disc and i t s physical 36 152 strength at this age, shown to be the 4th-5th decades of l i f e ' NACHEMSON and MORRIS have stated the opinion that "sufficient evidence is now available, although most of i t indirect, to justify the opinion that most low-back pain and sciatica (is) caused by changes i n the lower lumbar discs*^ 3. This receives support from the 119 120 pain studies performed by HIRSCH ' . LAWRENCE showed a relation-ship between lumbar disc degeneration and back-hip-sciatic pain, significant for a l l radiological grades of disc degeneration in males 152 but only for moderate or severe disease in females . He found disc degeneration to be a more common cause of such pain than disc prolapse, osteoarthritis, rheumatoid ar t h r i t i s or ankylosing spondylitis, and 39. f e l t that symptoms might arise from the ligaments, because of the pain patterns. Frank disc prolapse has been accepted as a cause of low back and 171 sciatic pain since the i n i t i a l report of MIXTER and BARR , even though the mechanism of pain production is not completely clear. Most l i k e l y inflammation is responsible for part of the pain as pain is not a feature of nerve entrapments, while steroids w i l l suppress the 198 pain of disc protrusion even i f given systemically The majority of patients with low back pain are probably not 64 suffering from nuclear herniation ; MACNAB has described five types 184 of pathogenesis of symptoms in disc degeneration : Type I Segmental in s t a b i l i t y (repetitive ligamentous strain). Type II Segmental hyperextension (pain due to chronic strain of the posterior joints). Type III Chronic posterior joint subluxation associated with disc narrowing. Root compression may complicate this. Type IV Posterior joint a r t h r i t i s - usually secondary to disc degeneration. Type V Root i r r i t a t i o n - may result from disc herniation, spinal stenosis; or foraminal entrapment, pedicular kinking, or extraforaminal engulfment of the nerve root. Undoubtedly, then, degeneration of the intervertebral joint is of central importance in painpproduction, but i t is not certain at what stage and in what individuals i t w i l l present. There is a lower 40. overall correlation of back-hip-sciatic pain with the lesser degrees 152 of radiological change , further, a normal radiograph is compatible 118 120 with considerable degenerative change ' . This variation may be 63 229 267 accounted for as superadded muscular pain ' ' or differences . 267, 293 in individual pain response As RABINOVITCH says: "Much ink has flowed on the subject of intervertebral discs. Those who float forth on the sea of literature on which disc problems s t i l l float should be. guided by the explorers... The explorers have demonstrated the Virchovian importance of the concept of disc degeneration, more information i s required regarding i t s link with pain and functional impairment. 84 METABOLIC: Osteomalacia i s probably a cause of backache , but is very rare in comparison with the high incidence of back pain. Osteoporosis i s much more common and has been demonstrated to be age-related. However, partly because of this relationship with age, i t has so far been impossible to demonstrate a correlation between osteo-245 porosis and backache . This is partly because of d i f f i c u l t i e s with techniques of measurement of osteoporosis covered especially in the actual skeleton; densitometry/ is l i k e l y to be of great assistance 129 in improving this gap in our knowledge Ochronosis may be a rare cause of low back pain, as may other 180 2 34 calcifications ' possibly due to pseudogout (chondrocalcinosis). 41. The calcification of ochronosis tends to be associated i n i t i a l l y with 180 stiffness rather than pain; acute disc herniation may occur INFLAMMATORY ARTHRITIDES: Although these may arise (ankylosing spondylitis}, rheumatoid a r t h r i t i s , gout) the incidence is low compared with the incidence of back complaints. Gout has probably not been f u l l y eval-uated as a cause of low back pain. As entities basically involving only the synovial joints, these w i l l not be detailed here. INFECTION: Infection may be a cause of acute or chronic low back pain, whether an acute purulent (e.g. staphylococcal) or chronic granulomatous process (e.g. tubercular). Even hydatid disease may be 179 a cause of thoracic back pain . Discussion of these also f a l l s out-side the scope of this paper. MALIGNANCY: An occasional cause of low back pain in the older pa-104 tient, e.g. as sacral metastases , or multiple myeloma. TRAUMA: Major trauma is not a common cause of low back pain. Only 15% of ROWE's series could relate an injury to the onset of low back pain . CAPLAN, FREEDMAN and CONNELLY did not think that disc degeneration was due solely to aging and found a relationship between narrowing of the disc spaces and previous injury but not between disc 42 changes and heavy work without injury . This study again i s based on radiological evidence. HULT found that in 60-65% of those who had 42. lumbago or sciatica attacks the symptoms had appeared without a 128 history of trauma or l i f t i n g strain . Repeated minor trauma may be a factor, but d i f f i c u l t to demonstrate except as in the next section. OCCUPATIONAL FACTORS: " the relatively high prevalence of disc dis-ease among heavy manual workers is strong presumptive evidence of the causal relationship but this i s less clear cut than in the case 7 of osteoarthrosis of the limbs" . However, the links between muscular effort and work and pain of indeterminate origin are much less cer-tain. Work by the Arthritis and Rheumatism Council in Edinburgh and Manchester demonstrates that although sickness absence rates do seem to be related to heavy jobs, age standardized complaint ratios in 18 widely ranging occupations showed no obvious correlation with heavy o jobs . Radiological evidence of disc degeneration i s more common in 152 heavy workers . HULT demonstrated a higher incidence of symptoms described as the lumbar spine syndrome in those engaged in heavy 128 work (64.4%) than i n those in light occupations (52.71) . Incapac-i t y to work was again much more prominent in those doing heavy work than in those in light occupations, demonstrating the greater socio-economic importance manifested in lost time in heavy occupations. Because of the high incidence of spinal symptoms in a l l occupational groups and a moderate difference between the light and heavy occupations 43. he concluded that heavy work could not be a fundamental cause in the changes causing these symptoms. He f e l t that objective c l i n i c a l signs of restriction of movement, tenderness on pressure suggested that the changes i n the lumbar spine were the most common causes of the syndrome. He did not suggest any trigger mechanism for these coming about or for complaints of back pain in the younger patient:. GOODSELL showed a slightly disproportionate number of laborers in his series of 406 1am-+ • 94 mectomies As part of the work of the Industrial Survey Unit of the Arthritis and Rheumatism Council job analysis was performed in terms o&i'.equired 7 muscle activity, posture and site conditions with precise grading . Increasing effort by back, arms or legs significantly increased the likelihood of disc disease in particular (this being a diagnosis based on history and physical alone) but outdoor conditions showed no such influence. TROUP has detailed the variations in permitted maximum weights 261 and heights over which they may be l i f t e d but feels that limitation of absolute maximum weights may only be a part of the answer in prophylaxis as repeated l i f t i n g of lesser weights may be harmful, particularly i f associated with accelerative or shear stresses. KOSIAK et a l f e l t 50 lbs to be a c r i t i c a l value above which time 147 loss was more l i k e l y to be severe . TROUP et a l are continuing a prospective t r i a l with detailed job description and laboratory anal-265 ysis of work stress : the results of this should be highly 44. illuminating. ILLNESS VULNERABILITY: It has been shown that a small percentage of people account for a disproportionate amount of illness while another small number are disproportionately healthy, according to a series of studies by HINKLE . The figures for CP. AIR (VANCOUVER) reflect this trend, showing 97% of leaves of absence to be taken by 21% of 113 staff . It has also been shown that the illness susceptibility of these people i s general (i.e. to different types of illness) rather 259 than specific . It was shown that these illnesses tend to cluster, so that one-third of an individual's illnesses are l i k e l y to f a l l into one-eighth of his years. This can manifest i t s e l f by two mechanisms, probably either independently or together: a great illness-reporting factor can be shown and greater actual morbidity and even mortality. THURLOW suggests that the "total man" may react to a threatening change with a wide variety of responses: behavioral, endocrine and 259 immunologic, which may then increase illness or accident proneness Once the symptomspattern has been formed, i t is possible for per-petuation to occur. PSYCHOLOGICAL:. Those with physical illness or even increased illness vulnerability may show psychological abnormality, according to STEWART FORD and LAM pointed out the importance of psychological assessment 81 of the patient with low back pain . PHILLIPS showed that neurotic 45. triad abnormalities in the Minnesota Multiphasic Personality Inventory were more marked in in-patients with low back pain than in those with fractures MAGORA demonstrated a high incidence of low back pain to be re-164 lated to high levels of education , while MACNAB found that lower intelligence was a determining factor i n the 'failure 1 of lumbar intervertebral fusion. Many authors agree that psychological ab-normality is important in the pathophysiology of low back pain be-r r+ 55, 56, 95, 100, 106, 267, 273, 275, 283, 285 fore or after surgery > > > > > > > > > but i t is rarely quantitated and has only been studied i n two con-209 272 trolled populations ' : the psychological aspects of one being 272 yet unpublished "This review has indicated that the growing interest in this f i e l d is a comparatively recent development and that much research s t i l l requires to be done to establish more clearly the. nature and cause of many :(jm^ £\ll?ostee'l5g.f^  pains especially in the back. back pains are numerically most important rheumatic causes of absence and permanent disab i l i t y and their effects are formidable in terms of loss of earnings; those affected also make 7 heavy demands on medical services." 46. MANAGEMENT OF LOW BACK PAIN. It i s not relevant at this point to discuss the detailed manage-ment of the patient with the complaint of low back and/or sciatic pain. Nor w i l l the methods of arrival at a specific diagnosis be detailed: by consulting the appropriate references these methods may be learned. However, an outline of such methods is presented as they are of importance in management of the patient eventually requiring fusion, which i s essentially an end-stage procedure. DIAGNOSIS AND ASSESSMENT HISTORY AND PHYSICAL EXAMINATION: These two subsections are covered . , . ... , 38, 40, 53, 61, 126, 148, 223, 225, 234, in detail by many authors > > > > > > > » > 242, 280 RADIOLOGICAL EXAMINATION: Many opinions are found regarding the appropriate features to be searched for on plain x-rays, usually comprising a combination of these views - antero-posterior, l a t e r a l , two obliques, spot lateral lumbosacral, u p t i l t anteroposterior lumbo-sacral and bending films in two planes 1 0' 6 1' 6 8' 6 9 ' 7 0' 8 7' 1 2 9 ' 132, 143, 143a, 144, 183, 186, 247, 281 Contrast studies include myelography, discography and epiduro-graphy; each has a specific, carefully delineated role to play, 47. each has a high rate of false negatives and false positives^ 1' 100, 102, 141, 142, 238, 277 c ., , ,, r ,, ' ' ' ' ' . Further work may soon allow f u l l stereoscopic visualisation of the lumbar spine through holography"*"^. PSYCHOLOGICAL ASSESSMENT: Many authors have stressed the importance of psychological factors i n low back pain, particularly with regard 15 51 183 249 to failures of surgery ' ' ' , but very l i t t l e has been written to assist in the interpretation of psychological abnormality 95, 201, 202, 209 ELECTROMYOGRAPHY: Suggested for use i n evaluation of the problem 92 249 patient, particularly before anterior fusion ' lower limb electromyography was reported in use by GURDJIAN in 517 patients, showing slightly better accuracy at the f i f t h lumbar disc level than contrast myelography (64.8% vs. 61.8%). Electromyography of the trunk muscles i n the patient with low back pain is s t i l l in the in-+. , + 63, 279a, 292 vestigational stage ' ' DIFFERENTIAL SPINAL ANAESTHETIC: The methods described by AHLGREN et a l , and BROTHERS and FINLAYSON were found of value by them and 92 183 by others ' . This procedure helps discriminate between pain predominantly of peripheral or central origin at the time of the examination. COMPUTERISED DIAGNOSIS: Early work on Bayesian analysis of patient data promises that the use of computer-assisted diagnosis may become 48. helpful 98 CONSERVATIVE MEASURES OF THERAPY For the purposes of simplicity, modes of management are described here without reference to chronicity of disease, according to which 280 they w i l l be of varying usefulness PREVENTION: a) Epidemiological research, identification of risk factors, patient education, improvement of occupational conditions 2 1 6. b) Maintenance of good overall physical condition , . . 127, 148 and muscular tone ' REST: The time-honored principle of rest, including bedrest i f necessary, is affirmed by a l l authors although bedrest prolonged beyond one month is 61 not l i k e l y to be of benefit . The load on the disc is considerably reduced in the reclining .+. 191 position TRACTION: 53 S t i l l recommended by some this has been shown to have negligible effect in reducing the load 191 on the lumbar intervertebral disc in vivo . It is probably of most value as a means of enforcing bedrest i n the recalcitrant patient. 49. ANALGESIA: This is mentioned as a basis of conservative therapy; narcotics should be used only in the emergency phases of treatment12'''. MUSCLE RELAXANTS: Used for the benefit of central and peripheral e f f e c t s 1 6 2 , diazepam is representative and has been shown electromyographically to reduce muscle 12 spasm . It has been suggested, however, that muscle relaxants should only be used as an 127 adjuvant to bedrest and in one such double-blind t r i a l they were shown to be ineffective DE PALMA and ROTHMAN suggest the major use of relaxants to be in the acute phase 6 1. Diet i s of importance in the obese patient to 127 reduce stresses on the lumbar spine DIET: 117 PHYSICAL THERAPY: The aspects of concern hereare heat, posture and exercise. Heat i s for symptomatic r e l i e f of pain, the aims of therapy concerned with posture and exercise: are more fundamental. Postural correction and education is thought to ease biomechanical stresses on painful joints in the low back and exercise to develop musculature to sustain im-, . 40, 61, 72, 127, 148, 280 proved posture ' ' ' ' ' 50. LUMBOSACRAL IMMOBILISATION: Widely used as corset or brace in assisting therapy, or as a plaster cast to assist i n diagnosis, the mechanism of action is unclear and the c l i n i c a l usefulness not proven. As they do not produce immobilisation and may increase muscle activity, i t is possible that the mechanism of action is by increase of intraabdominal pressure or by limitation of motion in certain directions 6 1' 1 2 7> 1 6 3> 2 0 8> 2 6 8. EPIDURAL INJECTION: As rest may produce r e l i e f of pain by allowing inflammation to subside 6 1, so may suppression of inflammation be of importance in the use of epi-dural steroid injection, which has found success , , 37, 55, 238, 285 in many hands ' ' ' . OPERANT CONDITIONING: For the chronic patient not in a position to be helped by physical methods, modification of pain 83 behaviouB may be of benefit . REHABILITATION: This v i t a l part of the treatment of any condition 1 7 0 ' i ' ) / ; 0 7 1 must be on a personal level ' ' as well -i 135, 182, 183, 210 as on occupational basis ' ' ' . 51. Compensation on a practical! basis may be an 135 210 essential part of rehabilitation ' ,and may . r i 169a influence recovery The results of the nonoperative treatment of low back pain w i l l 102 be discussed in conjunction with the operative treatment OPERATIVE THERAPY Surgical treatment w i l l be considered under six headings: manipulation, discolysis, surgery of specific 'non-disc' lesions, discectomy, decompressive laminectomy and fusion. MANIPULATION: Although this may be considered an aspect of physical therapy, and may defer the need for surgery, i t is an operative method. It is practiced by a limited number of physicians primarily because of lack of training, partly because of lack of knowledge of the mechanism r +. 37, 38, 54, 55, 56, 127, 157, 280 of action ' ' ' ' ' ' ' DISCOLYSIS: S t i l l a controversial procedure, chemonucleolysis has been per-formed with two enzymes: collagenase and chymopapain. Each is specific; collagenase breaks down collagen to proline, hydroxyproline and glycine (mainly), while chymopapain attacks the protein mucopolysaccharides, 52. forming keratosulfate, chrondroitin sulfate and protein. SUSSMAN states that collagenase, which w i l l not attack the c e l l membrane and is rapidly inactivated by serum, i s much safer than chymopapain which has been more widely used but has been associated with f a t a l sub-254 arachnoid hemorrhage, but that further investigative work i s needed SPECIFIC 'NON-DISC SURGERY: Appropriate surgical or other therapy may be required for these potential sources of pain: sacral nerve root cysts, dural cysts, narrowing of the sacral c a n a l o r spina bifida of SI with impinging L5 spinous process^ 9' 6 1' 2 4 8 . Removal of the posterior vertebral 231 90 elements may be required for spinal stenosis , spondylolisthesis 241 of Paget's disease ; excision i s required for chordoma or occasion-234 ally for 'kissing spines' DISCECTOMY: The indications for pre-, intra- and post-operative techniques and complications of disc removal (often incorrectly referred to as 2 15 29 6*7 laminectomy) have been well covered in the literature ' ' ' ' 88, 90, 100, 101, 102, 171, 177, 194, 195, 196, 213, 214, 217, 143, ' as well as i n the standard orthopedic and neurosurgical texts. Here i t w i l l suffice to consider the results of treatment. Table 2 summarises the results of discectomy with or without fusion as given by several authors. The only two studies comparing the long-term follow-up of patients with discogenic pain treated 53. surgically or conservatively f a i l to demonstrate any differences in 102 196 the overall results between the two groups ' . Both point out that a s t r i c t comparison is not possible as i n i t i a l selection of the patients biases the results; a prospective controlled t r i a l with 196 random assignment of subjects is suggested . Earlier studies demonstrating a degree of preference for surgical treatment were based on short term follow-up^' ^' ^ . HAKELIUS has shown that in selected cases where a definite disc protrusion i s found 102 earlier return to f u l l activity may be possible with discectomy 124 177 Bilateral disc exploration probably produces better results ' , recurrence is more frequent following unilateral discectomy. Most of these quoted authors eventually f e l t that in view of the increased convalescence and morbidity, with l i t t l e difference in results, 15 100 fusion should be performed only at a later date i f necessary ' ' 194, 280^ p e w k a v e S Uggested that fusion should be performed simul-227 252 taneously ' ; results then have not been found significantly better and no recent arguments have been given for the practice (See also following section). Decompressive laminectomy may be used as an adjuvant to disc-ectomy i f the pain i s atypical and i t is f e l t that the sagittal diameter of the canal is narrowed 2 9' "^9' 2 3 1 . 54. LUMBAR INTERVERTEBRAL FUSION. The rationale of the operation of lumbar intervertebral joint arthrodesis i s that pain i n certain cases arises from a mechanical derangement occurring at one or more parts of the intervertebral joint and hence can be abolished by elimination of motion at that particular joint. The history of the operation has been well review-75 720 ed by BICK arid ROLANDER . INDICATIONS: The main indication for arthrodesis of the spine 53 was tuberculosis at the time of HIBBS and ALBEE . It i s s t i l l of primary importance in selected cases of pyogenic or tubercular spon-d y l i t i s , but these f a l l outside the f i e l d here being considered. Indications for lumbar intervertebral fusion have included the following: 216 258 1) Narrowed disc space with vertebral displacement ' 2) Spondylolisthesis 5 7' 2 1 1 ' 2 2 8 ' 2 5 2 ' 2 5 8 ' 2 8 6 3) Certain congenital anomalies, e.g. hemivertebra, sacrali-+. 127, 228, 252, 258 sation ' ' ' 194 252 4) Failure of pain r e l i e f by previous laminectomy ' r . c • r r • 211, 216, 228, 258 5) Symptomatic non-union of a fusion ' ' ' 252 258 6) Disc herniation in heavy worker:. ' 7) I n s t a b i l i t y 1 2 7 ' 2 2 8 ' 2 5 2 55. 8) Long-term backache 2^ 2 127 252 9) Disc space entered at surgery with no protrusion found ' 228 10) Retrospondylolisthesis 11) Charcot spine 3 4 211 12) Spondylolysis For a detailed historical review of the indications for fusion, the reader i s again referred to the introductory section in the treatise by ROLANDER220. The maj.<3r controversy regarding fusion concerned i t s role at the time of discectomy, suggested in the i n i t i a l paper of MIXTER and BARR especially i f there was ins t a b i l i t y of the spine. A multitude of , ,15, 52, 100, 101, 203, 213, 227, 276 +, papers were published ' > > > > » > • the cumu-194 lative opinion was expressed by NACHLAS , as Chairman of the Research Committee of the American Orthopedic Association, that results of discectomy with simultaneous fusion were slightly better, with partic-ular reference to a slightly lower incidence of residual backache in those with added fusion. However, the Committee saw no reason why fusion could not be performed at a later date, particularly in view of the fact that, at that time, the average hospital stay was 15 days where excision only was performed, 58 days for the combined operation. The types of fusion and their major features are outlined in Table 3 . The three major categories are 2^' 2 2 0 : 56. Posterior fusion (e.g. HIBBS, ALBEE, BOSWORTH types)involves placement of bone graft material between laminae and/or spinous pro-cesses. Posterolateral or intertransverse fusion (e.g.WATKINS) in which blocks or slivers of bone are placed between the transverse processes. This may be combined with the posterior fusion. Interbody fusion (e.g. CAPENER, MERCER, HARMON) may be anterior or posterior (more commonly the former). In each case, the principle i s the same: to cause bony fusion, usually by applying autogenous cancellous bone graft to the prepared surfaces of adjacent vertebrae. Internal fixation may be applied i n 30 140 207 159 the form of screws ' ' or plates , but this is only to assist in immobilisation u n t i l the bone becomes mature and solid. RESULTS: It was shown by SMITH in 9 autopsies on patients 25 who had had Hibb's fusions that solid bone resulted , and i t was subsequently assumed that solid bony fusions should provide r e l i e f from pain and that pseudoarthrosis would generally be associated with pain. However, ROLANDER demonstrated experimentally that although posterior fusion has a stabilising effect and causes redistribution of the load on the disc, the intradiscal pressure is reduced only when loads are applied near the fusion and increased strain may re-220 suit from more anterior vertebral unit loading , which would seem to approximate the in vivo situation. The disc was also found to be 57. essential for weight-bearing, as excision resulted i n fracture of the posterior parts on loading and ROLANDER f e l t there would be less chance of achieving a stable posterior fusion where discectomy has been performed. NACHEMSON and MORRIS showed in vivo that loads in discs spanned by a posterior fusion in two patients were only about 193 30% less than would have been anticipated i n the absence of fusion In the one with a pseudarthrosis, further loading increased the intra-discal pressure to a value similar to subjects without fusion. In the other, surgically demonstrated to have a successful fusion, the force on the disc was proportionately reduced by further loading. However, NACHEMSON's load figures are calculated from nuclear pressures and do not convey any information of asymmetry of disc loading. C l i n i c a l l y , the success of fusion has usually been evaluated according to the subsequent rate of pseudarthrosis^' "^' 1 5 3 ' 1 8 5 ' 207, 258, 269^ additional information concerning work habits, and reported pain patterns: in fact LEVY et a l f e l t a solid fusion to be the most important single factor in obtaining a satisfactory 153 result . However, several authors have produced results casting doubt on the functional significance of pseudarthrosis^' ^ ' In a series of 594 patients with a total of 1165 fused levels, CLEVELAND et al showed the overall pseudarthrosis rate to be 16.7%, varying from 3.4% in lumbosacral fusions to 33.3% i n L3-S1 and L2-S1 fusions^. They found that of a l l patients i n whom pseud-arthrosis is developed, 41.4% were relieved of the pain and dis a b i l i t y 58. present before operation. Application of a test of independence (with YATE's correction) to their data shows that i n fact pseudo-2 arthrosis and r e l i e f of pain were not independent (x = 167.45, p < .005). However, the fact that so many patients with proven pseudoarthrosis (and the figures are lower than many series) were s t i l l relieved of pain i s of great interest. BARR et a l found of 120 multiply-operated patients, those with 16 a solid fusion had a greater chance of having a better result In a series of 448 post fusion patients with a follow-up period of five to seventeen years, DE PALMA and ROTHMAN demonstrated pseudoarthrosis by motion on bending x-rays i n 8.91 or thirty-nine patients 6 0. This group was controlled by thirty-nine others with the same diagnosis and operation but a solid fusion. The incidence of complications, time of return to work and to previous activity levels, attitude to surgery, r e l i e f of symptoms and pain distribution patterns were the same in both groups (no significant differences on Chi-square analysis). They f e l t that pseudoarthrosis per se should not be considered 'failure' of a fusion operation. Even the presence of a solid combined anterior and posterior fusion only occasionally gives complete pain r e l i e f 1 1 9 . The diagnosis of pseudoarthrosis i s also d i f f i c u l t , as methods include various techniques from c l i n i c a l examinations with evidence of tenderness up to and including surgical exploration, recommended 59. 159 by CLARK . X-ray examination probably is not conclusive u n t i l two 57 119 years have passed ; even then i t is unreliable o . However, more series give the results of surgery in terms of the incidence of A • u • • • + 16, 30, 34, 108, 153, 185, pseudoarthrosis having primary importance ' ' ' ' ' ' 207, 211, 216, 215, 252, 258, 269 , , . » » » » » » than those who use predominantly c l i n i c a l considerations for success 2 3 , 4 1 ' 4 6' 6 0' 6^' 1 4 0 ' 1 9 4. Hence when we consider the reasons suggested for 'failure' of the operation, the bias is towards those factors tending to produce pseudoarthrosis; indicated by an asterisk, (also included here are disability*producing complications). 6 153 211 1) Failure to obtain solid fusion or graft fracture ' ' ' 216, 258, 269 2) Psychologically 'unsuitable' patients 1 6' 8 9' 2 3 3 ' 2^ 2' 2^ 8' 285 3) Cases with complicated compensation claims 1 6' 2 8^ 4) Adhesions of nerve roots +_ their sheaths 1 6' 7 2' 1 1 9 ' 2 1 6 ' 2 3 3 16 5) Pain threshold too low * 6) Inadequate bone g r a f t i n g 4 6 * 7) Use of other than autogenous cancellous bone 4 6' 1 0 8 ' 1 8 1 ' 2 1 1 * 8) Infection 4 6 * 9) Fracture of a previously solid f u s i o n 4 6 * 10) Crossing of previous laminal defects 4 6 11) Arachnoiditis 8 9' 2 3 3 * 12) Fusion of more Hihan one l e v e l 8 9 ' 2^ 2' 2 5 8 89 * 13) Wide laminectomy, providing poor bed 60. 14 15 16 17 18 19 20 21 22 23 24 25 26 6 111 185 2 2 2 Acquired (post-fusion) spondylolysis ' ' ' Nerve root i r r i t a t i o n by fixation screw 1^ Lumbar hernia at i l i a c donor site - rare n .159, 269 Donor site pain ' 158 159 Lateral femoral cutaneous nerve pain n • -t . - 185, 205, 244 Spinal stenosis ' ' 233 Surgical technique 01 O *Z *Z Failure to recognise involvement of another level ' 233 258 Compensation pressures ' 233 Failure to diagnose other than vertebral pathology 233 Cephalad progression of disc degeneration Generalized disc degeneration 2 1 6' 2 3 3 ' 2 5 2 ' 2 8 5 Donor site pain (as related to technique: peripheral nerve 252 entrapment)' 27) Obesity 2 5 8' 2 8 5 This l i s t of reasons given for 'failure' of the fusion operation is far from exhaustive of the extremely extensive literature: i t i s , however, representative. It should be stressed that there is no commonly agreed-upon formula for assessing the results of operation, which are variously based on patient opinion by questionnaire or interview (usually considering only pain patterns and reported work habits), physical examination, radiological examination or a com-bination of the three. 61. A summary of representative results i s presented in Table 4 . Disability evaluation has not been formerly considered as a form of assessment of the patient who has had lumbar intervertebral fusion. The concept w i l l be presented in the discussion section. 62. SUMMARY OF LITERATURE. It is clear that certain pathophysiological mechanisms are responsible for creating a .potentially painful situation in many individuals. What is not yet clear i s why some individuals develop what we c l i n i c a l l y understand as pain: behaviour causing a patient social arid economic distress and having profound emotional effects on both patient and family. Insofar as these structural or pathological abnormalities are of relatively uncertain significance, in the unoperated patient, so are they i n the-postsurgical patient, in whom i t is just as impor-tant to determine the relative roles of the multiple factors in-cluding the role played by the surgeon himself. The purpose of the study, then, was to ascertain the relative importance of selected measurable parameters and evaluate these in terms of previous work. MATERIALS AND METHODS - PILOT STUDY The subject materials for. the i n i t i a l , pilot, phase of the study were a l l World War II Canadian veterans who had had lumbar inter-vertebral fusion during the seven-year period 1962-$968. The operation had been performed with or without laminectomy at one or more levels for low back and or sciatic pain, and the Boucher technique had been used in a l l cases. The numbers that could be traeeddand re-examined were limited by geographical situation and availibility of current address to 28 patients, a l l with a follow-up since fusion of at least two years. In each case the patient was sent a short explanatory letter requesting his attendance at a specified time at the outpatient department of Shaughnessy Veterans Hospital. Failure to attend on the first occasion was followed by a repeat request, by telephone or letter. A history and examination coded form was completed as each patient was seen by the author or other orthopedic resident. The format of the examination and design of the forms is discussed in the appropriate section regarding the main phase of the study. The patient was seen by a psychology graduate student who followed an interview by the administration of several objective tests, include the Wechsler Adult Intelligence Scale, Minnesota 64. Multiphasic Personality Inventory, Cornell Medical Index and Mooney Problem Check List. A l l subjects completed the f i r s t two tests, except •for one who refused the MMPI; the latter two tests were introduced in the course of the project, after the f i r s t three and seven subjects respectively. Data analysis was performed in terms of the succes or failure of fusion, assignation to one of three outcome groups being decided by the patient's score on an arbitrarily designed rating scale (See Table 5 ). It was felt, when trying to decide to which outcome group each patient should belong, that the relative "success" of fusion is too often made dependent, in the literature, on such factors as solidity of fusion or amount of analgesia required, for example. It seemed that a more comprehensive method of assessing surgery was required and hence the main categories were selected, relating to employment, pain, mobility of the lumbar spine, the patient's and orthopedic examiner's overall impression. With the peak score of 27, the patients were divided into quartiles, with selection of the lowest and highest scoring quartiles respectively as the good and poor outcome groups, the remainder being called "fair" results. Part of the purpose of the i n i t i a l phase of the study was to gain experience in the application of computer methods to patient data analysis, therefore a l l patient information was transferred 65. to punched cards and an IBM 360 computer used to display the results as bivariate frequency tables of result grouping vs other variables together with the percentages. The statistical significance of selected intergroup differences was performed subsequent to the evaluation of the displayed results. MATERIALS AND METHODS - MAIN PHASE For the major portion of the study, i t was necessary to select a group of patients who had.had lumbar intervertebral fusion who were accessible to recall and for whom fairly good medical records were obtainable. Such a group was found in patients i n i t i a l l y presenting with a compensable low back disorder. Recent addresses were on the records kept at the Workmen's Compensation Board of British Columbia, especially i f any form of contact was being maintained, either because the patient was receiving medical treatment or might s t i l l be on some form of compensation payment. The files were drawn of any patient who had had lumbar inter-vertebral fusion more than two years previously. This was done in a retrograde manner, year by year, until a satisfactory number had been seen. Where the information of patient identification was not avail-able by coded cross-indexing, prior to the summer of 1966, this was sought from the major general hospitals of British Columbia's metropolitan areas. The patient's medical record at the Workmen's Compensation Board was f i r s t summarised for purposes of future reference, while a c a l l - i n letter was sent out under the heading of the Orthopedic and Trauma Research Unit, University of Briti s h Columbia, stressing the voluntary, research nature of the examination and stating the hours l i k e l y to be involved. Recompense for time loss and travel was promised, and in view of experience gained i n the p i l o t study, each patient was requested to bring reading glasses, i f used. The letter was personally signed. Shaughnessy Hospital was used as the place of appointment, because of suitable f a c i l i t i e s for a l l examination procedures and i t s neutrality compared to the Workmen's Compensation Board premises. If the patient did not appear for the i n i t i a l appointment, further letters were sent, with subsequent registered letters and telephone calls as necessary to confirm the address or unavailabili of each subject. No one refused to attend, few made attendance impossible by conditions imposed. Correspondence with one or: two was continued at great length to try and achieve a high follow-up 0 rate. Of 141 subjects called, 101 were seen. Six were found to be deceased, c a l l in letters were returned by the post office on 20, about whom no current information could be obtained. Fourteen patients were unavailable for various reasons, either work or finance-related. On those with whom contact could not be established in some way, efforts were made to determine i f , in fact, these patients had died and, i f so, their cause of death. This proved difficult but some information on our limited data was supplied by the Department of Vital Statistics in Victoria. The patient was usually seen first by the orthopedist, who would obtain historical data and administer the Patient Self-Evaluation Questionnaire (Appendix 1 ) before performing complete physical examination. This would include particularly detailed evaluation of the lumbar spine and lower limbs. The patient's opinion of the result of surgery was sought, and recorded, and a brief assessment of his personality was made. The Cold Tolerance Test (a form of pain tolerance test) was then administered (Appendix 3). Radiological examination involved the use of nine views -anteroposterior, lateral, two oblique and spot lumbosacral views and bending films in two planes. If surgery had been more recent than four years prior to the date of examination and appropriate x-rays taken elsewhere in the preceding six months, these other films were obtained instead of subjecting the patient to a repeat x-ray exposure; this was also done i f surgery had been over four 6 8 . years previously and the roentgenogram taken in the preceding year. The patient's compliance and understanding was obtained and he was told the x-rays might be made available to other physicians at their request. At this stage he was also reminded that no other information would be released to any other physician or other agency without the patient's written consent, to ensure confidentiality of in-formation and avoidance of any "compensation bias". The patient was usually provided with lunch before seeing the psychologist, who conducted a structured interview and then admin-istered the psychometric tests used. In most cases the completion of a l l tests was done at the time of attendance but in some cases the patient was allowed to complete them at home and mail them in. This was done where performance of the tests was unduly prolonged because of language difficulty or other reason. The psychological tests selected were as follows: (1) Cattell Culture Free Form A Intelligence Test. This was substituted in favour of the WAIS used in the pilot study because of difficulties with language experienced with some subjects: the Cattell having no verbal component. (2) Minnesota Multiphasic Personality Inventory. Selected as a well evaluated and controlled screen for organic and non-organic personality problems. The Baron ego strength scale, Taylor "At" anxiety scale and the Hanvik Low Back Pain Scales were used to 69. supplement the basic c l i n i c a l scales. The M.M.P.I. i s based on a 566 item questionnaire (Appendix 4). (3) Beck Inventory of Depression. Used as a more sensitive and accurate measure of depression than the Depression Scale of the M.M.P.I. A 21 item questionnaire (Appendix 5). (4) California Personality Inventory. An index of personality relating to social functioning, and f a i r l y highly developed. A 480 item questionnaire (Appendix 4). (5) Kilpatrick-Cantril Self-Anchoring Scale (Appendix 6). In this, the patient i s shown, on paper, a "ladder of l i f e " . He i s asked to verbally describe his worst conceivable l i f e situation in writing at the bottom of the ladder, the most perfect at the top. He is then asked to make a mark on the ladder to indicate his position relative to the extremes at the time of last fusion, the present, and the future (5 years hence). The distance of the marks from the bottom of this ladder i s then scored. Data was collected in a standardised fashion and entered on four forms. It was hoped to thus readily transfer the information, on completion of the study, to punched cards for subsequent computer analysis. Inevitably, certain faults became apparent in the design of these forms later in the study and subsequent improvements made, as they were after the p i l o t study. Basically, data was collected in six relatively discrete sections. 70 . 1) Historical information (history of back condition, of other diseases, family and personal history). Examiner administered. 2) Patient self-evaluation information. A reproducible way to assess functional impairment and activities of daily living is by written questionnaire. In most cases patients were left alone to complete this. Because of language difficulty, a few subjects re-quired assistance. 3) Physical examination. This included an overall examination of the major systems with attention to detail regarding the low back and lower limbs. A brief assessment of personality was made by the orthopedist and he also administered the Cold Tolerance Test. 4) Psychological patient data - mostly historical. Obtained by the psychologist in his interview. 5) Psychological test data. This was collected in the usual fashion for the Cattell Culture-Free Intelligence Test, the Minnesota Multiphasic Personality Inventory, Taylor Manifest Anxiety Scale, Beck Depressive Inventory, Kilpatrick-Cantril Self-Anchoring Scale and the California Personality Inventory. 6) Radiological data. This entailed the interpretation of the standard lumbar spine views and measurement of specific items in these x-rays. X-ray interpretation was completed at the close of the clinical phase of the study. Data processing was performed with the assistance of the 71. University of British Columbia Computer Centre. A l l data was trans-ferred to punched cards and subjected to the U.C.L.A., Frequency Count Routine, providing a cell count and percentage, the range, median, mode, mean, standard deviation arid standard error of the mean for each variable. This program also produces a simple histogram for each variable, thus providing at a glance the approximate subject distribution. To enable a numerical index of "success" of the intervertebral fusion to be developed, factor analysis of 20 variables falling into 12 categories was performed, described in a later section. This factor analysis was performed at the University of British Columbia Computer Centre, using the program "UBC FAN" developed by Jason Halm from the UCLA BMDX 72 program (1971). It was decided to name the first variable on the unrotated matrix "success" and to use this in sub-sequent analyses. An intercorrelation was then made of the patient's scores.on "success" and 239 of the variables recorded, excluding a l l the re-membered information for 'one month before fusion' on the self-evaluation form and the multi-level nominal variables, such as occupational category. Some data transposition was necessary for this to improve the ordinal or quantitative characteristics. The program UBC C0RR by Ann Floyd and James H. Bjerring of the University of British Columbia Computer Centre (1969) was used, data being pro-cessed in blocks of 60 variables, 120 being the maximum number 72. acceptable i n a single run. Correlation methods used were the corre-lation ratio (ETA), Jasper's coefficient of multiserial correlation (M) and Pearson's coefficient of correlation (R) as appropriate for the variable types, with suitable significance tests. The p (prob-a b i l i t y of significance) values were entered on a matrix for evaluat-ion (Table '6). Fifty; five of the variables showing significant correlation with "success" (p<.0T), excepting those used i n i t s i n i t i a l deter-mination, were then again subjected to factor analysis, the program "UBC FAN" again being found most useful. The seventeen (17) resultant orthogonal factors were assessed and described according to the load-ings on the Varimax rotated matrix and their nature confirmed using oblique rotation. The factor scores for each patient were then correlated with "success" and the importance of the factors in accounting for the variance of "success" thus determined. RESULTS - PILOT STUDY (28 WW2 VETERANS) The results w i l l be summarized here and certain aspects high-lighted, as a primary aim was to evaluate the methods for the main phase of the study and to allow for their modification. The method of grouping the subjects was described in the appro-priate section (p 54 ) . HISTORICAL Age (mean) in years: Group 1 2 3 Overall At examination 50 54 55 53.3 At onset 33 27 26 27 Time lapse onset/fusion 9 18 15 15 Sex: Male 26 subj ects Female 2 subjects Occupation: Group 1 2 3 Overall Unable to work permanently 15% 21% 71% 32% > One week lost in previous 2 yrs 0 57% 100% 54% Return to work (after surgery) within 4 months: 1 2 3 Overall 43% 36% 0 28% Pension: Group 1 2 3 Overall D.V.A. pension for back 28% 78% 85% 68% Medical history: 21% had no other health problem on enquiry. 14% of each group 2 and 3 had some gastrointestinal complaint compared with none i n group 1. Back history: Trauma of some type was associated with the onset of symptoms in 57% of group 1, a l l of group 2, 86% of group 3, with a significant direct relationship to the severity of the back condition on review. Operative history: Group 1 2 3 Overall Single admission 57% 21% 0 25% More than 1 fusion 0 30% 43% 25% A l l those having one or two pseudo-arthrosis repairs f e l l into the f a i r or poor group. Symptoms: 11% of the total were symptom-free; pain alone was the dominant symptom in 64%. It was f e l t in the back alone in 32%, predominantly in the back in 32%, in back and legs equal-ly in 11% and the legs alone in 7%. PHYSICAL General: 43% of the total demonstrated some abnormality on examination which would include, for example, a single operative scar. 22% showed some ab-normality on rectal examination 75. (group 1, 0%; group 2, 46%; group 3, 15%) which o f t e n took the form of coccygeal tenderness: no d e t a i l was recorded. G a i t : A m i l d abnormality of g a i t was found i n 11% o f the t o t a l (28% of group 3). C e r v i c a l or t h o r a c i c spine: Group 1 2 3 O v e r a l l L i m i t e d motion or tenderness 0 35% 57% 32% Lumbar lordosis': Tenderness: A s i g n i f i c a n t l y g r e a t e r degree of abnormality was seen i n the poorer-f a r i n g p a t i e n t s , w i t h a m i l d e r a s s o c i a t i o n between r e s u l t grouping and muscle tone o f the abdominal and p a r a v e r t e b r a l muscles. Group 1 2 3 O v e r a l l 43% 86% 100% 79% U s u a l l y l o c a l i s e d to a spinous pro-cess but not apparently r e l a t e d t o the f u s i o n l e v e l . N e u r o l o g i c a l : Group 1 Impaired s t r a i g h t l e g r a i s i n g 0 C a l f or t h i g h asymmetry 0 Sensory impairment 0 2 65% 43% 36% 3 71% 34% 57% 76. Result of surgery: Group 1 2 3 Overall Permanent definite improvement 100% 35% 0 43% Partial improvement 0 57% 14% 29% Temporary improvement 0 0 57% 14% Worse or 'other' 0 8% 29% 14% Under the same circumstances (the patient would): Group 1 2 3 Overall Accept surgery again 100% 71% 71% 79% Refuse surgery again 0 7% 14.5% 7% Undecided 0 22% 14.5% 15% RADIOLOGICAL Congenital anomalies: Two patients, one i n each of groups 1 and 3, had a separate facet epi-physis, each at a single site. Spondylolysis was seen in a single patient at the L5 level. Myelogram dye: A few drops seen i n 29% of group 1, 57% of group 2, 86% of group 3. Level of fusion: Group 1 2 3 Overall L5 SI 86% 36% 0 39% L4 SI 14% 50% 71% 46% Pseudoarthrosis: Screws: Degenerative changes: Kissing vertebral spines: 77. Groups 2 and 3 each had one patient fused from L3 to SI and one fused at the L4 5 level. None seen in this series although four patients had previously been operated on for this. A l l had had Boucher fusion. The presence of bent or broken screws did not correlate with the result group. More changes of disc degeneration were seen in the lumbar spine of the poor result patients, as evi-denced by the presence of osteo-phytes (good correlation) lesser overall disci' height and increased posterior joint subluxation. The presence of traction spurs and measures of retrospondylolisthesis. These were seen in 40% and corre-lated neither with the results nor with the presence of spinous tender-ness in the same patient. 78. Lumbosacral angle: Mean angle (degrees) PSYCHOLOGICAL Group 1 2 3 Overall 137 139 141 139 These differences did not reach significance at the p < .05 level. For details of these see WILFLING ; the results are summarised here. The mean I.Q. (using the W.A.I.S.) was 107.2, showing no correlation with the groups. There was no differ-ence between the group i n their educational background. 59% of the total had a documented history of psychopathology, ranging from schizophrenia to alcoholism, but uniformly distributed across the groups; most had had their referrals postoperatively. The differences in M.M.P.I. profiles are illustrated in Figure 2. Group 2 shows the "conversion V" configuration of the neurotic triad (scales 1, 2, 3) with 1 and 3 (hypo-chondriasis and hysteria) showing a 79 . greater elevation than 2 (de-pression). DISCUSSION - PILOT STUDY After performance of the pilot study, certain conclusions were reached, the implications of which could be further explored in the main phase. These conclusions were as follows: 1) Posterior lumbar spine fusion may be associated with few com-plications and have a very good fusion rate, yet s t i l l f a i l to re-lieve disabling pain in over one-third of the patients who remain permanently unemployed because of back pain, while over one-half may s t i l l lose some time at work because of backache. 2) The early onset of the disease and a larger time lapse from the onset of symptoms to fusion are associated with poor results. 3) Poor socioeconomic status of the patient may be associated with a poor outcome of spinal fusion. 4) The patient with poor surgical results may suffer more from other disorders such as poor muscle tone, deficiences of the cervical and dorsal spine, or gastrointestinal system. 5) Multiple procedures are associated with poor end results due possibly to progression of degeneration, inadequate preoperative patient selection or the adverse psychological effects of multiple 80. surgery, or to greater preexistent psychological abnormality. 6) Poor results are associated both with evidence of more ad-vanced disc degeneration and more severe psychological abnormality. The reasons for the association require further investigation. 7) Psychological investigation i s useful i n the i d e n t i f i c a t i o n of patients with poor surgical r e s u l t s , and i t might be that through preoperative psychological assessment the number of f a i l e d back surgery patients could be reduced. These findings were borne i n mind i n the design of the major study, and at the same time they have provided information of use i n the c l i n i c a l setting. However, a detailed discussion of the problems concerning the etiology of low back pain and i n p a r t i c u l a r the possible causes for f a i l u r e of the operation of lumbar in t e r -vertebral fusion required more sophistication of experimental approach and hence i s deferred u n t i l the results of the second phase are considered. 81. RESULTS OF THE MAIN PHASE (100 W.C.B. PATIENTS). HISTORICAL DATA. Of 141 patients mailed a c a l l - i n letter, 101 attended. Twenty letters were returned by the Post Office for patients whom we were unable to trace. The fact that there was no current address at the Workmen's Compensation Board implied that they were not receiving compensation payments. Six were deceased, 14 were unable to come because of pressure of work or financial d i f f i c u l t i e s ( i t was only possible to recompense the subjects after they had attended). One patient had to be excluded because of the extreme poor quality of x-rays, taken elsewhere. Percentages are used except where stated, decimals indicate missing data, usually because of failure to answer a question or refusal, by the patient. Age Mean (years) Minimum (years) Maximum (years) at examination 44.1 22 67 at last fusion 39.7 17 63 at onset of symptoms 34.8 16 59 Time from onset of symptoms to f i r s t surgery (Median) 18 months. Sex Male 92% Female 8% Birth place British Columbia 31% Other [.provinces of Canada 41% 82. Ethnic background Occupation United Kingdom 9% North or West Europe 7% South, Central or East Europe 10% Other North American French or French Canadian British Mediterranean North or Western European Central or Eastern European 2% 48% (North American Indian - 1%) 6% 17% 4% 14% 11% This information, obtained for the time of the last fusion operation and the present, showed two-thirds to be s k i l l e d workers, one-third unskilled, with one executive and an accountant, employed as a stevedore at the time of surgery. Thirty four per cent f e l t their work habits were unaffected by their back. Thirty six per cent stated that they had changed to a different job type because of their back dis a b i l i t y . Forty-nine per cent had made no change in employment, figures for the actual number of changes for the re-83 mainder. reflected only the nature of their work. Time loss Sixty per cent had missed from a few days to many months of work during the last two years because of their back problem: 11% were un-employed (median time loss for the total was 1-2 months). Medical history Forty - four per cent had a history of "sig-nificant" illness in the past, evenly distrib-uted across the systems. This would include hepatitis, renal stone, pneumonia, for example, but excluded peptic ulcer disease, which had been diagnosed in 26%, with various modes of therapy received. Another 31% suffered dys-peptic symptoms with perhaps professional or self-medication but without a formal diagnosis being made. Twenty-six per cent had had major abdominal surgery (excluding appendectomy). Seven per cent had had psychiatric atten-tion prior to fusion, 4% subsequently, 1% both. A further 2% described moderate or severe tranquilliser use. Three per cent had psoriasis, 23.5% had 84 quite frequent rashes or itching. Back history Ninety -six per cent experienced the onset of symptoms i n association with an episode of trauma, which was relatively major in 22%. The total number of back-related hospital admissions varied from one (12%) to nine or more (7%). Operative history With a range of 1-7, the mean number of back operations was 1.98. The mean number of fusion operations was 1.47, with a range of one (in 66%) to four (2%). The number of laminectomies ranged from zero (18.2%) to three (6.1%); mean 1.13. Complications of the last operation (as obtained from the patient or his Workmen's Compensation Board f i l e ) had been suffered by 28%, (wound infections, 9%), excluding pseudo-arthros i s . The pathology described at the last operation included: No abnormality 26% Bulging disc 16% Herniated disc 9% Pseudoarthrosis 19% Fibrosis and scarring in canal 1% 85 . Congenital anomaly 4% Combination or 'other' 20% No report 5% Microscopic changes were only rarely looked for. The time missed from work prior to the last back operation varied from less than one month to over 10 years, the median being 4-6 months. The time for return to work varied from less than one month to 'not al a l l ' , with a median value of 4-6 months. Family history It was d i f f i c u l t to obtain a reliable family history due to poor memory or lack of communi-cation with distant branches of the family. The median number of siblings of the father was four; 7.1% admitted a history of back trouble i n their father or his siblings. The equivalent figure on the mother's side were five siblings; 4.8% admitting a history of back trouble. The patient had a mean number of offspring of 2.15 at the time of his last fusion, 2.27 at the present. Nine per cent stated that a single child had experienced some back trouble; 2%:2. 86. Personal habits Smoking : Alcohol : Drugs : SYMPTOMS Pain Non-smoker 281 Cigarettes <10 daily 10% Cigarettes 10-20 daily 32% Cigarettes >20 daily 24% Pipe or cigar (moderate use) 6% Abstainers 10% Special occasions only 7% Occasional drink 18% Once or twice most weeks (in moderation) 35% Weekly drinking evening 7% Daily drink 14% Relies on alcohol 5% Unequivocally alcoholic 1% Ex-alcoholic or A.A. member 3% None 96% Ex-addict of opiate 1% Has tried some 'hard' drug 3% Patients placed themselves in the self-evalua-tion scale thus: No pain 17% '0 Mild pain 24%Pain annoying, absent on activity 11% Pain present during activity 15% Moderate pain, interferes with activity or sleep 24% Pain prevents activity or sleep 9% Of those with pain, most had low back pain with or without lower limb pain. Eight per cent of the total had pain in the limbs„alone Pain at other sites described thus: Interscapular Neck Coccyx None 54% 51% 66% Occasionally 25% 24% 23% Often 6% 16% 5% Most of the time 10% 9% 6% Factors affecting pain Improvement Exacerbation Coughing, sneezing or straining 2% 26.3% Sitting on a firm or upright chair 34% 21% Sitting i n a comfortable or re-clining chair 16% 35% Lying f l a t 44% 12% Lying curled up 36% 18% Walking 23.2% 29.3% 88. Improvement Exacerbation Bending 4% 52% Li f t i n g 1% 51% Heat 50% 0% Cold 2% 41% Manipulation 7% 8% Corset or orthopedic type belt 291 5% Analgesic such as aspirin 22% 0% The percentage unaccounted for i n each category is provided by those who indicated "no particular effect on the pain", "have not tried i t " or "cannot t e l l " . In 54% pain was either absent or bore no relationship to the time of day while i n the remainder the pain was time related, usual-ly being worse in the evening or night. Other symptoms Stiffness : noted in the back and/or lower limbs by 67%. Weakness : this was f e l t by 55%; 11% b i l a t e r a l l y , 23% in the l e f t leg, 21% in the right leg. Sensory change : described by 60%; 18% b i l a t e r a l l y , 20% in the l e f t leg, 17% in the right leg, and 5% in other parts (e.g. one ulnar neuropathy). Sleep impairment : 42% said they experienced back discomfort as a cause of d i f f i c u l t y in sleeping. 89 ACTIVITIES OF DAILY LIVING Household chores: Self-care: F l e x i b i l i t y : Mobility: 70% stated they could manage to carry a heavy suitcase, mcve heavy furniture or do heavy digging in the garden; the remainder described various degrees of limitation. Four per cent could manage nothing in the house. 71% described total independence, the remainder stated a need for help with some aspects of self-care such as dressing. 49% could descend into or rise out of a chair without discomfort while the others found that the act of s i t t i n g and/or rising was painful. 54% stated they were able to retrieve dropped items from the floor without d i f f i c u l t y ; 42% would experience d i f f i c u l t y , 4% could not pick up things from the floor. 53% found no limit to the distance they were able to walk, 21% have to stop after a half-mile be-cause of discomfort, 17% after 2-3 blocks, 9% had even less range. Similarly, 48% found back-related discomfort would mildly or moderately limit their a b i l i t y to drive while 9% could 90 . drive, at most, locally only. 52% had back-related limitation of a b i l i t y to ride in a bus or car, with riding discomfort being usually more pronounced than d i f f i c u l t y mounting or dis-mounting . Work and financial: Work habits have been described. Mean income (recorded as $ 100's per month) ranged from $ 100 to $ 400 monthly, with a mean of $ 852 (S.D. 530), 13% f e l t themselves to be comfortably off, 33% stated they were free of debts but would like to have more money in re-serve, 45% admitted to small debts and 9% found themselves in a f a i r l y serious financial posi-tion. Marital: status was as follows: Single 7% Married (one marriage only) 65% Married (more than once) 17% Common-law marriage 4% Separated 1% Divorced 3% Widowed 3% Regarding contentment within the existing marital framework, the 91. following responses were obtained: Single at present 13% Happy and f a i r l y secure 62% Fairly happy, but obvious ups and downs 18% Relationship not very good 6% Likely to s p l i t up soon 1% Sexual problems werealso categorised: No back related sexual d i f f i c u l t y 62% Certain positions necessary because of back pain 7% Frequency limited by back pain 14% Both the above are true 17% Social l i f e : Limitation of miscellaneous social activities was considered: No back-related limitation 48% Some type of activity, reduced frequency 13% Change to easier activities 28% Very l i t t l e possible because of pain 11% Children: None under age fifteen at home 46.5% Able to' work and play with them 40.4% No rough games or l i f t i n g possible 8.1% Very easy games, talking or reading only 4.0% Cannot share activities at a l l 1.0% 92, General quality of l i f e : Enjoy l i f e As above, but less than before back trouble Back problem spoils things most of the time Life i s only just tolerable because of the back brouble Enjoyment of l i f e more affected by other problems 44% 39% PHYSICAL FINDINGS PHYSICAL 76% were described by the examiner as being normal and healthy; 20% appeared overweight for their height; 4% appeared pale and thin. Blood Pressure: 85% had a normal blood pressure, 14% a diastolic blood pressure over 90 mm. Hg., 1% diastolic over 120 mm. Hg. Body dimensions: The mean weight was 75.9 kg. Mean body height was 173 cm. A measure of obesity for correlation was expressed weight_code 1 Q d d , £ a t £ a c t , height code ' 93. ENT: 88% had no ENT abnormality. The abnormality in 12% was usually a perforated tympanic membrane. Chest: 4% with abnormality had emphysema or a thoraco-tomy scar. Heart: 3% demonstrated abnormality, none requiring re-ferral . Abdomen: Abnormalities were categorized thus: Normal 7-5% Obese (marked) 2% Two or more scars 18% Both the above 2% Hernia of any type 3% Rectal: Normal 74% Fissure and/or hemorrhoids 9% Coccygeal tenderness 6% Tenderness of sacrotuberous ligament. 5% Coccyx and ligament tender 3% A l l three 1% Refused 2 % 94. ORTHOPAEDIC EXAMINATION Stance: Normal 64% List to right 14% List to l e f t 16% List forward 6% Gait: Normal 93% Right leg limp 1% Left leg limp 4% Difficulty both legs 1% Problem with recent foot operation 1% Lumbar curve: Normal lordosis 48% Flattened lordosis 42% Kyphosis 1% Scoliosis - right convex 2% Scoliosis - l e f t convex 2% Flattened and right scoliosis 3% Flattened and l e f t scoliosis 2% Pelvic t i l t : Normal 90% Left side higher 10% Paravertebral muscle tone: No paravertebral spasm Left-sided spasm 84% 2% Bilateral 14% Abdominal muscle tone (standing): Normal Obese, f a i r tone Not obese, but poor tone Obese, poor tone 77% 16% 2% 5% Cervical spine: Normal Limited motion Tenderness (axial or local) Other abnormalities (e.g. curvature) 4% 16% 7% Overlap of these categories accounts for a total greater than 100%. Upper limbs: 83% 4% Normal Shoulder crepitus on motion As above, limitation of motion 1% Neurological impairment (ulnar palsy) 1% Other 11% The last category included scars, missing digits etc. Thoracic spine: Normal Abnormal curve Limited rotation Marked tenderness 94% 3% 2% Range of motion; Lumbar spine. Cervico-sacral increment: Distance measured from C7 to SI spinous process and the increase on flexion recorded. >8 cms , 14% 7.1 - 8-cms 27% 6.1 - 7 cms 25% 5.1 - 6 cms 16% 4.1 - 5 cms 9% 3.1 - 4 cms 7% 2.1 - 3coms 1% 1.1 r 2 cms 1% Finger-tip reach: Touch toes 14% Below mid-tibia 24% Mid-tibia 39% Touches knees 17% Mid-thigh 6% Paravertebral muscle spasm on flexion: None 80% Moderate 15% Marked 5% 97. Extension estimation:Normal 21-30 degrees 11-20 degrees 1-10 degrees 0 degrees Pain on extension: No Yes 3% 26% 42% 25% 4% 66% 34% Lateral flexion: A combination bilateral index was used for this , based on a coding for each side, so that a score of 0 would indicate normal lateral flexion; 6, in a b i l i t y to reach beyond mid-thigh on either side. The frequencies were: 0 12% 2 29% 3 14% 4 35% 5 7% 6 3% Passive hyperextension: F u l l , pain free Slight pain, normal limit Mild pain 57% 10% 98. Moderate pain Severe pain - relieved by flexion Pain not eased by flexion . Tenderness Most prominent site: None Spinous process S-l joint right S-I joint l e f t Paravertebral muscles right Paravertebral muscles l e f t Greater trochanter Other (e.g. donor site) Secondary site: None Spinous process S-I joint right S-I joint l e f t Left buttock Paravertebral muscles right Paravertebral muscles l e f t Other Spinous Process tenderness: None 99 . L l L2 L3 L4 L5 SI Superficial A combination variable ('Tender') was for purpose of analysis, coded thus: 1 normal - no tenderness 2:1 place tender 3:2 places tender Gaenslen test (sacro-iliac stress): Normal Right positive Left positive Productive of marked back pain Equal Right shorter by 1-5 cms Left shorter by 1-5 cms Lower limbs  Length of legs: Peripheral pulses: Normal Marked decreased right 100. Hips: Normal 98% Right abnormal (possible O.A.) 2% Knees: Normal 84% Right abnormal 7% Left abnormal 6% Both abnormal 3% In most cases abnormality consisted of a menis-cectomy scar or degenerative change. Ankles: Normal 94% Right abnormal 2% Left abnormal 2% Both abnormal 2% Right foot: Normal 90% Hallux valgus 1% Claw or hammer toes +_ calluses 2% Abnormality of arch § hammer toes 1% Other (e.g. scars, absent digits) 6% Left foot: Normal 88% Abnormality of arch 2% Hallux valgus 1% Claw or hammer toes +_ calluses 2% Abnormality of arch § hammer toes 1% 101. Other Neurological examination  Straight leg raising pain: Bowstring sign: Muscle wasting: None 42% Right 0-30 degrees 2% Right 31-60 degrees 3% Right 61-90 degrees 9% Left 0-30 degrees 2% Left 31-60 degrees 3% Left 61-90 degrees 7% Both legs 0-30 degrees 6% Both legs 31-60 degrees 14% Both legs 61-90 degrees 12% Pressure over the taut popliteal nerve. Negative b i l a t e r a l l y Positive l e f t Positive right Positive b i l a t e r a l l y None Asymmetry of thigh or calf (2 cms), wasting of anterior calf muscles or ext. dig. brevis 2% 9% 3% 74% 26% 102. Abdominal muscle power: (A) a b i l i t y to l i f t straight legs 10 cms off the table. Present 94% Absent 6% Abdominal muscle power: (B) a b i l i t y to l i f t upper body off the table with legs secured. Normal - f a i r l y easily 56% With d i f f i c u l t y - but a l l the way 17% Moderate d i f f i c u l t y - only part way 22% Marked d i f f i c u l t y - only just able to move 5% Back muscle power: a b i l i t y to l i f t buttock off the table when supine. Normally and easily 59% Remains extended with some d i f f i c u l t y 23% Moderate d i f f i c u l t y - cannot sustain i t 4% Marked d i f f i c u l t y - unable to raise buttocks 14% Lower limb muscle power: this was recorded in the standard fashion (grades 0-5) for each of the following muscle groups: Hip flexors, extensors, abductors and adductors; 103. knee extensors and flexors; foot dorsiflexors, 0 plantar flexors, evertors; great toe extensors 0 and flexors. Results for each group were coded: Left Right 0 0 Grade 5 1 1 Grade 4 2 2 Grade 3 3 3 Grade 2 4 4 Grade 1 5 5 No function A compound index for analyses (LEPGOW) was derived by summating the coded scores for each of 22 categories. These categories represent the 11 different muscle groups (hip abductors, adductors, flexors, extensors, etc.) conventionally examined and recorded bi l a t e r a l l y (Appendix l ). No effort was made to record the examiner's opinion of the nature of weakness, but the impression was gained that organic weakness was always well localised. Results: Normal 70% 1 11% 2 3% 0 3 4% 5 3% 6 1% 104 . 7 2% 8 2% 11 1% 19 1% 20 11 24 1% .Deep tendon reflex (knee): the more severe change was scored. Normal 87% Heft decreased 21 Left absent 2% Both increased 1% Both decreased 7% Both absent 1% Deep tendon reflex (ankle): the more severe change was scored. Normal 50% Right decreased 5% Right absent 8% Left decreased 2% Left absent 15% Both decreased 7% Both absent 13% Plantar reflex: Normal 98% 105. Abdominal reflex: Absent both sides Abnormal because of local disease Cremaster reflex: Normal Absent right Absent both sides Abnormal because of local disease Sensation (right), level of impairment: None L4 dermatome L5 dermatome 51 dermatome 52 dermatome More than 1 root involved Peripheral nerve loss Sensation ( l e f t ) , level of impairment: None L4 dermatome L5 dermatome SI dermatome a More than 1 root Peripheral nerve loss Combination of above 106. A combination index (LOSSRL) was made to in-dicate the presence or absence of sensory loss: Normal 52% Abnormal 48% EVALUATION OF AND B¥ THE PATIENT Motivation for surgery: (as remembered by the patient). Patient i n i t i a l l y refused surgery 1% Surgeon suggested i t , after con-siderable conservative therapy 76% Surgeon suggested i t , after l i t t l e conservative therapy 23% Patient's opinion of last operation: Permanent definite improvement . 54% Permanent partial improvement 23% No improvement 7% Temporary improvement <2 years 7% Some worsening 2% Definitely worse 5% Other (e.g. had no complaint prior to surgery) 2% Under the same circumstances: (the patient would). Accept surgery again 78% 107. Refuse surgery again 17% Undecided 5 % Reasons for surgery: (as understood by the patient) Purely on surgeon's recommendation 2% To relieve pain 88% To prevent further trouble 1% To improve weakness 4% To improve back function 1% Other 4% Examiner's opinion: Patient definitely improved 58% Patient partially improved 19% Worsening - progressive disc disease 5% Worsening - emotional disease 2% Temporary improvement - now worsening 6% The same, or qualified 10% PSYCHOLOGICAL PATIENT EVALUATION BY THE ORTHOPEDIC EXAMINER. A l l patients were evaluated on ten psychological measures to assess the usefulness and significance of such measures by an orthopedic examiner. Scores of 1 through 7 were assigned for each; the scores are l i s t e d in Table 6 . 108. COLD TOLERANCE.TEST The median time for performance of this test was 135 seconds. 5.*5% reached the cutoff time of 180 seconds and, at the average temperature of the water of 4°C, a l l these f e l t that they could have kept their hand immersed for a longer period. Handedness: Right handed 92% Left handed 8% INTERPRETATION OF THE X-RAYS Number of lumbar vertebrae: 4 distinct lumbar vertebrae 2% 5 distinct lumbar vertebrae 88% 6 distinct lumbar vertebrae 4% Incomplete transitional 6th vertebra 6% Sacral anomalies: Normal 71% Congenital (e.g. spina bif i d a , transitional L5) 15% Acquired (e.g. sacroiliac osteoarthritis) 14% Separate facet epiphysis: None 97% L l 2% L5 1% 109 . Scoliosis: Spondylolysis: Osteoporosis: None 10-20 degrees None L4 99% 1% 93% 4% L5 3% Of these seven subjects, two had spondylolysis of L5 and fusion at the L4S1 level, three others with L4S1 fusion had spondylolysis at the L4 level; of two with L5S1 fusion, one had spondy-lolysis at the L4, one at the L5 level. Of those with spondylolysis above the fusion level, three were b i l a t e r a l , two unilateral in appearance. Spondylolisthesis: None Grade 1 Grade 2 89% 10% 1% this was graded visually. None seen Grade 1 Grade 2 Grade 3 88% 5% 5% 2% Old fracture: (of body or transverse process). None seen 89% 110. Present 11% Myelogram dye: None seen 42% Few drops 53% Moderate amount 5% Evidence of laminectomy: (with visible evidence of bone removal) None seen 90% L4 2% L5 4% Combination 4% Type of fusion: Posterior bone graft only 22% Boucher type 48% Posterolateral 6% Apophyseal screws and bone graft 7% Anterior interbody 2% Other types (Wilson plates, posterior interbody) 4% Combinations 11% Level of fusion: L5-S1 40% L4-S1 46% L3-S1 4% L4-5 7% L3-4 1% Other (e.g. L3-4 and L5-S1) 2% 111. Solidity of fusion: Solid fusion 67% Pseudoarthrosis (at either level i f 2 are fused) 33% Criteria used in assessment of fusion required at least two of: visible defect in bone mass, persistent posterior (apophyseal) joint space, motion on bending films in one or both planes (in the absence of rotation). Number of screws: None 34% 1 1% 2 41% 3 6% 4 16% 5 1% 7 1% Abnormality of screws: No screws 34% Normal screws 50% Bent 14% Broken 2% Schmorl's nodes: None seen One site More than one site 89% 5% 6% 112. Knutsson's sign: (the "vacuum" phenomenon) Not seen L5S1 L4 5 Posterior joint degeneration: None seen One level, unilateral One level, bilateral More than one level Traction spurs of anterior longitudinal ligament None Present at one site More than one site Osteophytes: (excepting above) None One site More than one site Ligamentous calcification: None Localised one level More than one level Kissing vertebral spines: None 113. One level 32% Two levels 9% MEASUREMENT ON THE X-RAYS. Lumbosacral angle: the angle formed between the axes of the L5 and SI vertebral bodies ranged from 127 to 173 de-grees. The mean was 143.1 degrees (+_ 8.84). Measurements were made at as many levels as possible of the following a variables: (Figure 3) Vertebral body height (front and back) Intervertebral disc height (front and back) Posterior joint subluxation above the joint-body line. Retrospondylolisthesis of each vertebral body on the next lower. Interpedicular distance. Sagittal diameter of canal. Each was measured to the nearest millimetre. A mean value for each subject was also derived, using only paired anterior and posterior values in the case of the vertebral body and intervertebral disc heights. Values were also obtained for the purposes of correlation only of disc height, retrospondylolisthesis and posterior joint subluxation at the level above the fusion. These values, together with the number of complete observations possible, are li s t e d in Tables 7 through 12. 114. PSYCHOLOGICAL RESULTS The psychological results w i l l be given in two groups, consisting of the descriptive data obtained i n the structured interview and the objective psychometric test data. F u l l details and analysis are pre-sented elsewhere 2 7 9. DESCRIPTIVE DATA: Position i n birth order: obtained i n absolute terms, to be related to the number of siblings. Ranged as follows. First child 23% Second 29% Third 18% Fourth 9% Fifth 7% Sixth 5% Seventh • 4% Eighth 1% Ninth 3% Eleventh 1% Province of birth: Not Canada 28% British Columbia 31% Alberta 10% 115. Saskatchewan Manitoba Ontario Quebec New Brunswick Nova Scotia Size of community during childhood years: < 500 500-1,000 1,000-2,500 2,500-5,000 5,000-10,000 10,000-25,000 25,000-100,000 > 100,000 Unable to estimate :many moves Father's occupation: No father Farmer Small business (owned) Large business (owned) Professional Semiprofe s s i onal (e.g. te acher, accountant) Parents religiousness: Parents compatibility: Childhood happiness: 116. Blue-collar (clerk, agent, etc) 3% Minor supervisor 7% Major supervisor 4% Service employee 7% Labour 30% Unemployed 1% Other 3% None 26% Very 18% Moderately 27% A l i t t l e 12% One parent not, one quite religious 13% Very moral, not religious ( i f given spontaneously) 4% rated on a seven-point continuum, scores 0-70 ("99" = no score) Range" 0-99 Mean 40.9 S.D. 21.13 rated on a seven-point continuum, scored 0-70 ("99" = no score) Range 5-70 117. Mean S.D. 48.7 16.45 Any of family "sickly": (up to 3 scored) None Father Mother Samed sexed sibling Opposite sexed sibling Uncle, aunt Age of leaving home permanently: Range Mean Grade School - number of years completed: Range Mean University - number of years: None 1- 6 years Vocational School - number of months: None 2- 40 months Overall mean A B C 58% 90% 94% 14% 4% 1% 14% 4% •tn 8% 0% 0% 5% 1% 4% 1% 1% 0% 13-39 years 19 years 0-13 8- 83 95% 5% 65% 35% 3.2 months 118. Years of apprenticeship: None 1-6 years Overall mean School subjects: 68% 321 1.12 years Favorite Most Hated Cannot answer 11% 10% Mathematics 39% 21% A science 9% 7% English or a language 13% 37% History/geography 13% 12% Shopwork, agriculture, home economics 5% 0% Sports 3% 1 % Art, drama, music 6% 9% Other 1% 3% Religious change recently: Never religious Always religious Have changed to more religious Have changed to less religious Remain religious, have changed faiths 37% 25% 8% 27% 3% Armed Forces Service: None WW 2 (did not see battle) WW 2 (saw battle ) 59% 14% 13% 119. Korea (saw battle) Peacetime f.crcesonly Additional marital history: A Nothing to add 77% One divorce 14% Two divorces 1% Widowed once or more 2% One separation 3% One past common-law wife 3% Two or more past common-law wives 0% Status of present marital relationship: There i s none Ready to break up Would break up except for children Stormy but w i l l remain intact About average Above average Superb Sex l i f e : Not exposed to one L i t t l e - spouse f r i g i d or impotent L i t t l e - because of subject's back L i t t l e - because of subject's other troubles 120. Moderate - mutual 4% Moderate - spouse's lack of interest 7% Moderate - spouse's other troubles 6% Moderate - subject' s lack of interest 1% Moderate - subject' s back 10% Moderate - subject' s other troubles 2% A l l is well 40% Number of children now at home: 0 34% 1 17% 2 23% 3 17% 4 7% 5 2% Mean 1.5 Also supported by patient: None 90% Parent or grandparent 4% Parent or grandparent of spouse 1% Unrelated child or adult 5% Ownership of home or apartment: None 25% 121. Yes, large mortgage > $10,000 211 Yes, moderate mortgage $5-10,000 8% Yes, small mortgage < $5,000 14% Yes 32% Was a home ever owned? No 87% Yes - given up for financial reasons 5% Yes - given up for other d i f f i c u l t i e s 3% Yes - given up for convenience 4% Other 1% Mean Family income in $100's : (gross monthly) Range 1-40 Mean 8-52 Median 8 Sources of income: A B C No additional source - 26% 74% Business ownership 9% 3% 3% Investments 0% 7% 1% Patient works 79% 9% 0% Spouse works 6% 29% 4% Pension 0% 0% 3% Children 1% 2% 0% Welfare 1% 2% 0% 122. Insight: Does the subject think that personality or psychological status can have a bearing on the existence of on the experience of a back problem? No 24% Yes, a l i t t l e 7% Yes, a moderate amount 4% Yes, quite a b i t 8% Not for self, but for other quite . a b i t 10% Not for self, but for others a lot 33% Will not give a direct answer 14% Number of times psychiatric attention has been received: 0 82% 1 10% 2 1% 3 2% 4 3% 5 1% 7 1% Psychiatric attention f i r s t received: Range 0-25 years ago. Psychiatric attention last received : Range 0-25 years ago. 123. Psychiatric attention for rest of family: None 76% Parent 4% Sibling 6% Spouse 9% Offspring 4% Other 1% PSYCHOMETRIC DATA. INTELLIGENCE: The Cattell Culture-Free Test was used to avoid the bias normally introduced by testing mixed ethnic groups with a test including verbal performance, such as the Wechsler. The mean I.Q. was 83.18. PERSONALITY: this was assessed using four test: the Minnesota Multiphasic Personality Inventory, the California Personality Inven-tory, the Beck Inventory of Depression and the Kilpatrick-Cantril Self-Anchoring Scale. The means on the appropriate scales are as follows: (see Appendix45-6 for explanation). Scale Overall mean MMPI L 50.12 F 59.18 K 49.55 1 (Hs) 66.27 2 (D) 65.08 3 Hy) 63.79 Scale MMPI 4 (Pd) 5 (Mf) 6 (Pa) 7 (Pt) 8 (Sc) 9 (Ma) Si Es Lb Taylor CPI 1 Do 2 Cs 3 Sy 4 Sp 5 Sa 6 Wb 7 Re 8 So 9 Sc 10 To 11 Gi 12 Cm 13 Ac 14 Ai 15 le 16 Py 17 Fx 18 Fe Beck Kilpatrick-Cantril 124. Overall mean 57.70 56.70 56.10 58.44 58.15 59.32 53.16 48.64 59.01 18.46 46.07 45.76 47.20 49.38 49.71 43.62 43.74 44.66 48.67 45.06 47.79 50.67 43.58 46.29 42.48 50.82 44.55 51.78 8.04 Past Present Future 59.80 62.57 75.27 125. PRODUCTION OF THE "SUCCESS" FACTOR. No single measure was found to act as an index of successful function of the patient at the time of examination, and the success of a specific fusion operation cannot be rated by merely recording the overall impression of the examiner at the single follow up v i s i t . The reasons that the patient i n i t i a l l y sought medical help for. his back: the reasons for which the fusion operation was performed, are of paramount importance. The success of any form of medical treatment requires the complete rehabilitation of the patient with return to his normal a c t i v i t i e s , whether at work or during leisure, so that the usual responsibilities of breadwinner, spouse or parent can be resumed. From experience in the p i l o t study and a study of the appropriate portion of the literature, a l i s t of features was drawn up to be re-presented i n the derivation of a success index. The twelve features were: 1) Pain 2) Work 3) Finances 4) Household care 5) Self care 6) F l e x i b i l i t y of the body 126. 7) Mobility of self 8) Sleep impairment 9) Sex l i f e 10) Social l i f e 11) General quality of l i f e 12) Retrospective opinion of surgery The features were constituted by twenty variables, which are described in the following pages. Each variable encompasses some aspect of the patient's function which may show impairment due to the low back problem. Overall, they describe pain, employment, family finance, the activities of daily l i v i n g , quality of l i f e and the patient's own..view of his surgery. To derive a patient success score, factor analysis was performed. The s t a t i s t i c a l process of factor analysis assumes that the inter-correlations of these twenty variables can be explained by the fact that each i s an indirect measure of several factors, themselves un-related (orthogonal : non-correlating). A theoretical factor score is derived for each patient based on the correlation coefficients between the variables. The "success" factor was taken to be the f i r s t on the unrotated matrix, representing the most important source of total variance of the input dat* (40.1%). The computer program "UBC FAN" was used10'', developed from the UCLA BMD x 72 program. The patient scores on the f i r s t factor, "successV were used for sub-sequent correlations. 127. With the descriptions of the variables, the factor loading (F.L.) of each is given, which i s the correlation coefficient of that variable with the factor "success". Percentages are the frequencies or number of subjects f a l l i n g into each category. The variable name is as used in analyses. 1) Pain a) "Severity" - severity of pain FL = - 0.8078 1. No pain 17% 2. Mild pain, not a problem 24% 3. Pain annoying, but forgotten during activity 11% 4. Pain present even during activities 15% 5. Moderate pain, interferes with activities or sleep 24% 6. Pain prevents activity or sleep 9% 7. Severe pain, is immobilising 0% b) "Tender" - objective tenderness FL = - 0.6405 1. No tenderness 24% 2. Tender one site only - 30% 3. Significant tenderness at 2 distinct sites 46% c) "Coccyx" - pain in the tip of the tailbone FL = - 0.4107 1. None 66% 2. Occasionally 23% 3. Often 5% 4. Most of the time 6% 128. 2) Work a) "Work" FL = - 0.6402 1. Continuing usual work without d i f f i c u l t y 341 2. Not working normally - back related 461 - ascribed to other causes 7% 3. Unable to work because of back 13% b) "Loss" - time loss from work i n last 2 years FL = - 0.6336 1. None 40% 2. Less than 1 week, not (1) 2% 3. Less than 1 month, not (2) 6% 4. Less than 2 months, not (3) 4% 5. Less than 4 months, not (4) 6% 6. Less than 6 months, not (5) 3% 7. Less than 1 year, not (6) 11% 8. Less than 18 months, not (7) 5% 9. Less than 2 years, not (8) 12% 10. Unemployed for this period 11% 3) Finances a) 'Nincome" - mean family income i n $100 per month.FL = + 0.3994 Min $100 Max $4000 monthly Median $800 Mean $ 851 b) "Money" - financial circumstances FL = - 0.2219 1. I am comfortably off financially 13% 129. 2. I have no debts, but would l i k e to have more money in reserve 331 3. I have some small debts 45% 4. I am in a f a i r l y serious financial position 9% 4) Household care "Chores" - mark the most d i f f i c u l t that you can manage FL = + 0.3997 1. Cannot manage anything 4% 2. Washing up 3% 3. Cooking 1% 4. Cleaning kitchen 0% 5. Cleaning and tidying house 3% 6. Making beds 8% 7. Washing or polishing floors 4% 8. Carrying a heavy object such as a suitcase 18% 9. Moving heavy furniture 7% 10. Doing heavy digging i n the garden or similar 52% 5) Self care "Independ" - caring for yourself - mark the most you can do FL = - 0.5321 1. Unable to look after myself 0% 2. I can feed and wash myself but need help dressing 0% 3. I am able to do the above, I can cut my own toenails 16% 130. 4. I can dress myself completely but need help with some things 131 5. I am totally independent 71% '06) F l e x i b i l i t y of the body a) "Chair" - s i t t i n g , getting up FL - - 0.7518 1. Neither of these gives me any discomfort 49% 2. I can s i t down but getting up from the s i t t i n g position may hurt 25% Getting up does not hurt but actually s i t t i n g may hurt 11% 3. Both s i t t i n g down and getting up may hurt 15% 4. Because of d i f f i c u l t y I need help with s i t t i n g down and rising from a chair 0% b) "Floor" - picking things up off the floor FL = - 0.8120 1. I can pick things up off the floor without d i f f i c u l t y 54% 2. Bending hurts, but I can straighten up without d i f f i c u l t y 8% I can get down to pick something up but straightening hurts 17% 3. Both bending and straightening up hurts 17% 4. Because of discomfort I just cannot pick things off the floor 4% 131. 7) Mobility of self a) "Mobile" - walking. FL = - 0.7400 1. No limit to walking 53% 2. I have to stop after about half a mile because of discomfort 21% 3. I can only walk 2-3 blocks before I must rest 17% 4. I can only walk very short distances, but can manage stairs and get around the house 8% 5. I cannot manage stairs 1% 6. I need help to move even in the house 0% 7. I have to use a wheelchair 0% b) "Transpor" - riding i n a car or bus FL = - 0.7346 1. No back-related d i f f i c u l t y i n getting in or out or riding 48% 2. Difficulty with mounting or dismounting or 12% travelling i s uncomfortable 27% 3. Both the above (2) 9% I avoid car or bus travel whenever possible because of d i f f i c u l t y 4% 8) Sleep "Sleep" FL = - 0.7092 1. Normal sleep habits 48% Sleep impaired due to other illness in self or family 2% 132. 2. Difficulty in getting to sleep and/or early waking due to discomfort 42% Sleep impairment for reasons unknown 6% 9) Sex Life a) "Sex" FI = - 0.6490 1. Normal - no problem at a l l 59% Other d i f f i c u l t y in either partner 3% 2. Back pain necessitates the use of certain positions or 7% frequency i s greatly limited by back pain 14% 3. Both of the above are true 17% b) " S l i f e " - absolute "quantity" of sex FI = + 0.3078 1. No sex l i f e 11% 2. L i t t l e , for a l l reasons 19% 3. Moderate amount 30% 4. A lot 40% 10) Social Life "Social" - going out with friends; to parties or dances, etc. FI, = - 0.8305 1. No limitation for any reason 46% I have had to change activities for some other reason 2% 2. No change i n the type of a c t i v i t i e s , but less often because of pain 13% I have had to change to easier activities because of back pain 28% 133. 3. I can do very l i t t l e because of pain 11% 11) General quality of l i f e •"Life" FL = - 0.7017 1. I enjoy l i f e 44% My enjoyment of l i f e is more affected by other problems 1% 2. I enjoy l i f e , but quite a b i t less than I did before this back trouble arose 8% 3. Life is only just tolerable because of this back (or leg) discomfort 8% 4. I have even thought of suicide because of this problem 0% 12) Retrospective opinion of surgery a) "Opinion" - patient's opinion of surgery (last operation only) FL = - 0.7598 1. Permanent definite improvement 54% 2. Permanent partial improvement 23% 3. Temporary improvement, no improvement, or worse 23% b) "Again" - under the same circumstances, the patient would now: FL = - 0.5016 1. Accept surgery again 78% 2. Undecided 5% 3. Refuse surgery again 17% 134. It should be noted that: The variables differ in some instances from those in the appen-dices to improve the ordinal distribution. No weighting coefficients were applied to variables, and weighting of the 12 features i s only by the number of variables delineating that feature. Zero responses to certain variables reflect their design to allow for more severe d i s a b i l i t y , as was found in the patient's re-membered state one month prior to their fusion (not used here). The factor scores of "success" obtained thus were standardised, having a mean value of zero and unit standard deviation. The factor scores were used to assess overall response, for direct comparison with certain features, as the major independent variable in a mul-tiple correlation matrix and for subsequent assessment of success-related factors. "Success" i s a hybrid factor. The higher the score for an in-dividual, the more satisfactory i s his overall function to him, and this i s of much greater significance than the opinion of the ortho-pedic surgeon. Thus, those variables showing a high correlation with "success" are those variables which the successful surgeon w i l l seek to manipulate in the optimal manner. In a prospective study of fusion, regression analysis on "success" as the dependent variable w i l l en-able s c i e n t i f i c improvement in the application of the operation. 135. PERFORMANCE OF MULTIPLE CORRELATIONS AND THEIR EVALUATION. THE CORRELATION MATRIX The "success" factor scores and 239 other variables were used as input data for the program "UBC C0RR", providing coefficients of correlation and probability values for significance for each pairwise correlation of a l l variables. To more easily examine the output, the correlations were coded by significance thus: 'invalid' 1 = p < .01 2 = p < .001 3 = p < .0001 Invalidity implies an insufficient c e l l frequency for the appli-cation of the chi-square method of significance analysis (in the correlation of a nominal variable with other nominal or ordinal data). In general, variables were selected or recombined where possible to avoid this problem: this was not possible with certain variables. The resultant matrix is seen in Table 13 in greatly reduced form. The va-riables are li s t e d i n Appendix 1. The experimentwise error rate may become high when such multiple comparisons are made: the number of chance occurrences of "significance" being found can be calculated (probability p for not making a g-error commission = ( l - a ) c , where a = error rate, for example .01, c = 136. number of comparisons made). However, the use of such a formula i s d i f f i c u l t ; an approximation can be made by considering that "signif-icance" may occur once in 1000 times i f p = .01, hence in 28,920 pairwise correlations i f p = .01, 29 "significant" correlations might occur by chance. By rejecting a l l correlations f a i l i n g to reach the significance level p < .01, the number of falsely 'significant' re-sults is reduced. With this multivariate analysis (evaluation of many variables simultaneously) i t is possible to do one of two things: either to perform factor analyses to simplify the concepts, with certain hypo-theses in mind, or to isolate small sections of the overall correla-tion matrix to again simplify the problem. Both techniques are used here. SUCCESS: DERIVATION The basic purpose of the study being to determine the dimensions, or associated factors of success, the i n i t i a l concern was to determine the correlations of the "success" index. Fifty-five of the variables not used in the derivation of "success" were found to correlate significantly (p < .01) with the "success" score. To simplify the conceptualisation of the roles each played and to determine the importance of their contribution to success, factor analysis was again performed (using U.B.C. FAN) on the basis of the intercorrelations of these 55 variables. 137. Table 14 l i s t s the 55 variables used and the factor loadings. The variables are grouped according to their contributions to the respective factors (i.e. the f i r s t group of variables has the highest loadings on factor 1, the second group or cluster on factor 2, etc.). The factor loadings are also simplified by giving the f i r s t two f i g -ures of the coefficient, rounded off. Here 100 would represent per-fect correlation, 00 no correlation, and -100 perfect inverse corre-lation. Finally, the correlation coefficients of factors against success are also shown, along the bottom of the table. The factors are identified by representation and placed in order according to their correlations with the "success" index i n Table 15. These factors are, of course, orthogonal: they show absolutely no correlation with each other, and do not overlap. Being totally in-dependent, each independently accounts for a percentage of the va-riance of the "success" scores, and this percentage can be summated. (The percentage variance accounted for is found by calculating the square of the correlation coefficient X 100.) The total variance of "success" accounted for by the eight significantly-correlating fac-tors ( p < .05) amounts to 79.961. The interpretation placed on this i s that i f the "success" index is taken to represent the follow up functional status of the patient, this actual function may be dependent on many things, eight of which are represented by the significantly-correlating factors, each totally independent of each other. The optimum result i n an individual w i l l 138. be dependent to a large extent on the optimal representation of these factors (accounting for 79.96% of the variance) with the additional influence of the other factors shown (cumulative total of 89.11% of trie variance) and others not yet identified. SUCCESS: ANALYSIS As mentioned before (p 59) the determination of success of fusion operations has always been performed in terms of one or two • i • u i « - • - i i A * T , • 16> 30> 34, 108, 153, simple variables, particularly pseudoarthrosis ' ' ' ' ' 207, 211, 215, 216, 252, 258, 285 n., , . ,. , , although some studies have used predominantly c l i n i c a l considerations 2 3' 4 1' 4 6 > 6 0' 6 5' 1 4 0 ' 1 9 4 . Subsequently, i t is conventional to place the patients in discrimina-ting categories and then to compare the groups, much as has been done here with the p i l o t study. However, the derivation of a numerical index of success has not been used before, to the author's knowledge, except by NASHOLD and 195 196 HRUBEC ' , in a 20 year follow up of patients with herniated nucleus pulposus. Their method was identical to the one used here in the main phase of the study (which was developed independently) except for the actual variables used. The loadings of their ''dis-a b i l i t y index' are shown in Table (rounded off to 2 figures as in this work); this factor only accounted for 23.1% of the variance of the input dat<&. This compares well with the figure of 40.3% ob-tained in this study. 139. It w i l l be noted that they attached less importance to the pa-tient's subjective complaints. In their study, the d i s a b i l i t y index was used as the dependent variable in a regression analysis to deter-mine the relative importance of the variables recorded at the i n i t i a l hospitalisation of the patients (with the data available, the only factors clearly emerging as predictors of subsequent disability were age at the i n i t i a l hospitalisation and chronicity of the disease at that time). Regression aanalysis has been found of assistance here in the interpretation of the psychological results but in the c l i n i c a l set-ting w i l l be of more use in a prospective study. It is not of s t a t i s t i c a l value to place the patients in discrete categories entitled, for example, 'good', ' f a i r ' , and 'poor' i f the overall relationships can be better assessed by correlation or factor analysis, for example. Graphically, grouping may make interpretation easier, however (see psychological profiles by quartile grouping, Table i f , ) . These methods, then, have allowed the establishment of a multi-factorial etiology of the low back pain syndrome in this experimental setting and the identification of the proportional importance of the factors. They have not, in this study, established a causal role for these factors, merely an associative role, but clearly indicate:' their s u i t a b i l i t y for application to a prospective study for causal determination. 140. ASSESSMENT OF EXAMINATION METHODS - WHAT DO THEY INDICATE? Table 18' shows a correlation matrix of certain orthopaedic exam-ination results with the success index and certain psychological and radiological variables. It i s not possible to show the exact signif-icance of each number, which represents the f i r s t two figures (rounded off) of the correlation coefficient. A l l coefficients shown are sig-nificant at the p < .05 level, and an approximate guide would be that values shown over thirty-five are significant at the p < .01 level, over forty-five at the p < .001 level and over sixty at the p < .0001 level ( i t must be stressed that these are only very rough approxima-tions) Underlining indicates an inverse correlation between the two variables as recorded (see appendix 1). This section i s based on the table. "Success" (the f i r s t column) can be looked at again in terms of the factor analysis results (p 137. ) which explained the inter-correlations found between the "success"-correlated variables. The appropriate correlation coefficients in the f i r s t column again high-light the associated factors: numbers of operations and levels fused, intelligence versus neuroticism, lumbar degeneration and limitation of mobility, pain tolerance, muscle fitness and neurological deficits. "Severity" (of pain), as a constituent of "success" has a high correlation with i t and is included for additional comparison with certain variables. The purpose of assessment of range of motion is primarily 141. orthopaedic: to provide information on the underlying structural pa-thology so that appropriate therapeutic measures can be undertaken. It is implied that these measures are objective and representative of disease processes affecting, in this case, the lumbar spine. If this is so, i t should be possible to appropriately interpret the correlations of these variables as relating to organic pathology: i f not, usage of these methods should be re-evaluated. In this study, the standard methods of recording finger-tip reach (for forward and lateral flexion) and of visually assessing extension were used: the degree of pain on active and passive ex-tension were likewise recorded. Only one truly objective method was used - measurement of the cervico-sacral increment (p 96. ) and i t is apparent that this could be replaced by better methods. Likewise, muscle tone and power were assessed by standard methods (p 102. and Appendix 1). Deep tendon reflex abnormality and loss of sensation were recorded (p 104. and Appendix 1) and the time of immersion in the Cold Tolerance Test (Appendix 3). Ideally, each test should be specific, with minimal correlation with methods supposedly measuring another parameter. The inter-correlations w i l l be described under several headings. MECHANICAL LIMITATION: Measurements of organic range of motion which are demonstrating mechanical limitation should show significant correlation with age, degree of degeneration evidenced radiologically and the number of levels fused. "LUMFLEX" (cervicos acpal increment 142. limitation), "LUMEXT" (visually-assessed limitation of extension) and RLFLEX" (combined limitation of right and l e f t lateral flexion by finger tip reach) show correlations with age, unlike "FLEXTWO" (lim-itation of forward finger tip reach), "PAINEXT" (pain reported on active extension) or "HYPEREXT" (degree of pain on passive hyperex-tension). These latter measurements show higher correlations with "success" so that i t might be supposed that degenerative changes at the lumbar level are responsible. However, examination of the correlations with "DEGEN" (degree of posterior joint degeneration), "SPURS" (number of sites traction spurs of the anterior longitudinal ligament are seen), "OSTEOPHY" (degree of osteophyte formation), "BAASTRUP" (degree of pseudoarthro-sis formation between adjacent spinous processes), "DISCMEAN" (mean height of measurable disc spaces), "RETROAVG" (mean retrospondylo-listhesis of one vertebra on that below) and "LUXMEAN" (mean value of posterior joint subluxation in the lumbar spine) shows only "LUMEXT" and "RLFLEX" to be indicators of disc degeneration. The number of segments fused ("LEVEL A") is only seen to corre-late significantly with limitation of extension and pain on passive hyperextension and not with the other range of motion measures. PAIN TOLERANCE AND TENDERNESS: Hyperextension i s seen to be corre-lated with pain tolerance ("CTT") as is "PVTONE" (degree of paraver-tebral muscle spasm), but the measures of range of motion do not 143. correlate thus with pain tolerance, as shown by the cold tolerance test. Tenderness ("TENDER" - number of tender sites in the low back) is apparently a separate phenomenon and does not correlate with true pain tolerance. A l l the measures of motion except the cervico-sacral increment correlate with "TENDER" and similarly with "GAENSLEN", sup-posedly a measure of sacroiliac pathology which correlates, rather surprisingly, with ""RETROAVG" and "RETRONEX" (the mean amount of retrospondylolistehesis at a l l levels, and that occurring at the level above the fusion). The same measures also correlate with "PVTONE". PSYCHOLOGICAL ABNORMALITY: The psychological measures used in this matrix are "CAT IQ" (IQ as determined using the Cattell test), "BECK" (the score on the Beck Inventory of Depression), "MMPIHS" (the T-score on the hypochondriasis scale of the MMPI) and "TAYLOR" (the score on the Taylor Anxiety Scale). In this setting an inverse relationship of intelligence to depression and hypochondriasis is seen. Intelligence correlates inversely with a l l measures of limita-tion of motion except the cervico-sacral increment. It is also of interest to note that i t correlates inversely with certain radiolog-ical measures of degeneration, probably due to occupational factors, the manual laborer showing more degenerative changes. The measures of depression, hypochondriasis and anxiety a l l 144. correlate with limitation of range of motion (except cervico-sacral increment), pressure tenderness, hyperextension tenderness, Gaenslen tenderness, paravertebral muscle tone, also the number of levels fused ("LEVEL A") and degeneration as osteophyte formation and spinous process pseudoarthrosis ("BAASTRUP"). This may be partly age-related and partly a result of the fusion; however, as there is no correlation between the number of levels fused and the incidence of kissing spines the causal sequence could be hypothesised psychological abnormality -muscle tension - abnormal motion - Baastrup phenomenon. Retrospecti-vely, only hypothesis is possible. A further possible reason for the psychological correlations is involvement of other joints (e.g. the hip joint) by the motivational changes. NEUROLOGICAL DEFICIT: This was 'measured' as muscle weakness ("ABDPOW B", "BACKPOW", LEGPOW"), straight leg raising limitation by pain ("SLR"), presence of muscle wasting ("WASTE"), deep tendon re-flex impairment at knee or ankle ("DTRKNEE" and"DTRANK") and presence of sensory loss ("LOSSRL") for the purposes of correlation. Again, the picture is confusing: the measures of trunk muscle power impairment correlate highly with "success" (inversely), in-versely with intelligence, positively with psychological abnormalities (especially "BACKPOW") and limitation of motion except the cervico-sacral increment, which correlates only with abdominal power. "BACK-POW also correlates inversely with pain tolerance ("CTT"). There is 145. no age correlation. It would thus seem that these are two hybrid measures - back muscle weakness, is a function of emotion and pain tolerance, among other things, perhaps abdominal power i s less affected by these things and enters more into mobility and suppleness as an organic phenomenon. Straight leg raising limitation by pain also seems to be a hetero-geneous measure, showing correlations with pain tolerance, tenderness, the psychological phenomena and operative history. Also significant (p < .001) but not on this matrix i s the correlation (.66) of "SLR" with "BOW" (presence of a positive bowstring sign) Straight leg raising limitation does not correlate significantly with impairment of the deep tendon reflexes. Muscle wasting ("WASTE") also correlates with a positive bow-string sign (coefficient .47, p < .05) and with narrowing of the disc above the level of fusion ("DISCNEXT"). The inverse correlation with the presence of myelographic contrast medium on x-ray i s puzzling unless i t is rationalized that a patient who has had a myelogram w i l l have had accurate localisation and excision of a herniated disc - a known requirement for good result of discectomy. (Lower limb weakness is also correlated with the presence of myelogram dye and not to the number of operations - the dye i t s e l f may be a causative factor in lower limb neurological abnormalities.) The deep tendon reflexes are of interest: with no relationship to intelligence, only the ankle jerk shows correlation with "success", 146. the measures of psychological abnormality, degenerative changes and (slightly) with age (coefficient -.22, p < .1). Both deep tendon re-flexes bear a relationship to the number of fusions and overall num-ber of operations. It seems again that both structural and psycho-logical features are represented by these measures, particularly by the ankle reflex, while loss of sensation shows a similar pattern of correlation: EXAMINER ERROR: This is obviously a major potential source of variance in the recording of any of the orthopaedic measures and yet i t should be the easiest to eliminate- It is not possible to assess the observer error from the available data. Within the limits of a retrospective study, i t is again possible to say that the orthopaedic measurements are incompletely objective, unstandardised measures of a number of factors. The methods should aim, as far as possible, for an effective assessment of actual motion of the lumbar spine only, reflecting the biomechanical influences of muscle fitness, suppleness and degree of degenerative changes. The influence of pain tolerance i s unavoidable where limitation of the movement is by pain, and even psychological abnormality w i l l be re-flected as this affects tenderness or i s i t s e l f a product of pain, as w i l l motivation influences such as high ego-strength, but i t is essential to remove the error introduced by measurement across other joints and by permitting observer error to affect the measurements. 147. Methods are available for this. Basic measurements have been 99 made by inserting Steinmann pins into the spinous process or by radiological methods3' ^. To avoid pain or unnecessary exposure! to radiation, special skin markers have been used, with a f a i r degree 263 of accuracy on correlation with radiographic measures However, the simplest methods are those evaluated by McRAE, MOLL 173 187 and WRIGHT, ' i n i t i a l l y for evaluation of ankylosing spondy-l i t i s . These involve measurement of the relative motion of two skin marks from neutral to the extremes in the particular plane measured, in a similar way to that described for the cervico-sacral increment except that the (minimal) influence of the thoracic spine can be ex-cluded (for flexion) by making the two skin marks respectively 10 cms. above and 5 cms. below the lumbosacral junction. Most importantly, these measurements on 237 subjects correlated well with radiological measurement of motion: Correlation P Flexion .97 < .001 Lateral flexion .79 < .001 Extension ' .75 < .01 173 Normal data for this sample were published . An increase in mean mobility was found from the 15-24 decade to the 25-34 decade with a later progressive decrease. These methods w i l l be u t i l i z e d on prospective work planned. 148. THE RADIOLOGICAL VARIABLES - WHAT IMFORMATION DO THEY PROVIDE? Table 19 shows a correlation matrix of the radiological variables with the "success" index, certain psychological and mechanical vari-ables. Again, i t i s not possible to show the exact significance of each number which represents the f i r s t two figures (rounded off) of the correlation coefficient. A l l coefficients shown are significant at the p < .05 level and on the average the higher the correlation coefficient, the smaller the chance probability of i t occurring. Underlining indicates an inverse correlation between the two vari-ables as recorded. This section is based on the table; the variables are described in the section on the interpretation of the x-rays and in Appendix 1. The radiological variables used f a l l into several categories: Dimensions of the lumbar spine and the spinal canal. This in-cludes the number of lumbar vertebrae "NUMBER", "BODYMEAN", "DISCMEAN", "LUXMEAN", IPEDMEAN" and others representing the appropriate dimen-sions described elsewhere. Developmental abnormalities. These include, for example, the presence of Schmorl's nodes ("SCHORL"), the presence or absence of the Knutsson phenomenon of the vacuum disc, spondylolysis and spon-dylolisthesis. It should be noted that spondylolisthesis was recorded 16 7 according to MEYERDING's classification of four grades . This is slightly less accurate than the measure of retrospondylolisthesis shown as "RETROAVG" which measures the forward or backward displace-149. ment of the one vertebra on the vertebra below in millimeters. Degenerative changes. Here we could place osteoporosis which was an approximate visual assessment of the degree of osteoporosis, and the degenerative changes of the lumbar spine including "DEGEN" (pos-terior joint degeneration at one or more sites), "SPURS" (the pres-ence of traction spurs of the anterior longitudinal ligament), "OSTEO-PHY" (presence or absence of osteophyte at one or several sites), and "BAASTRUP" (the presence, at one or more sites, of kissing vertebral spinous processes as evidenced by approximation and remolding of the spinous processes). Degenerative changes are also evidenced by the presence of posterior joint subluxation (quantitatively represented by "LUXMEAN" and "LUXNEXT") or retrospondylolisthesis (quantitatively represented by "RETROAVG" and "RETRONEX"). Operative phenomena. This includes the. number of levels fused ("LEVEL A"), the solidity of the fusion ("SOLID"), the number of screws used ("SCREWS") or the abnormalities of such screws ("SCREWED"). The presence or absence of myelographic contrast medium is recorded as "DYE" and the observation of posterior arch bone removal was recorded as "LAMINECT". The reader is referred to the table for the analysis of a l l correlations and those of note will be described below. First, as before, "success" should be studied. The correlations may again be noted of "success" with severity of pain and the psycho-logical variables . "Success" shows an inverse correlation with 150. abnormality of stance, the number of levels fused, the presence of the Baastrup phenomenon and an increased lumbosacral angle ("LANGLE"). An inverse correlation with spondylolisthesis of .27 did not reach significance (p = .100), the trend indicates, however, the possibility of a better result i n those with spondylolisthesis. Severity of pain shows similar correlations with the abnormality of stance, number of levels fused and increased lumbosacral angle. The correlated increase of lumbosacral angle is d i f f i c u l t to explain in terms of transitional lumbosacral vertebra when one considers the absence of correlation of "success" with the overall number of ver-tebrae . Age, which correlates with depression ("BECK") but not anxiety ("TAYLOR"), correlates with abnormalities of stance in the form of a forward or lateral l i s t and also with degenerative changes of a l l types as might be expected. Depression i t s e l f ("BECK"), with i t s demonstrated correlation with age, also shows correlations with the degenerative features and in addition with the Knutsson phenomenon. This correlation with the Khutsson phenomenon is even higher in the case of anxiety as evi-denced by the Taylor Anxiety Scale. As i t was seen in only three patients i t is not possible to make any firm conclusions about this correlation particularly in view of the lack of knowledge of i t s 142 structural nature Biomechanical influences on the x-ray picture are seen by the correlations of obesity ("FATFACT"), weight, stance, curve of the lumbosacral spine and t i l t of the pelvis. Obesity shows interesting 151. correlation with "LYSIS", of .84 (p < .01). In four of the patients this was shown to be a spondylolysis acquisita and i t may be that obesity i s an etiological factor i n i t s production. Obesity also showed an inverse correlation with the visual assessment of osteo-porosis, presumably due to apparent increased density in the presence of increased subcutaneous fat. This points out the advantages of densitometry which, by i t s technique, allows for the compensation for increased body weight. This correlation of osteoporosis with the num-ber of levels fused and the mean height of the disc again illustrates the weakness of the method of visual assessment as has been described 1 79 by HURXTHAL, VOSE and DOTTER . It i s planned to use densitometry in future assessment of osteoporosis. Abnormalities of stance are seen to be correlated with the num-ber of levels fused, and disc degeneration or narrowing as evidenced by "DISCMEAN' and "LUXMEAN". Abnormalities of lumbar curve showed a high correlation with the presence of Schmorl's nodes (which were seen in 11% of the sample). This high correlation may be due to a mechanical factor with the increased likelihood of central disc pro-trusion or maybe due to different centering of the x-ray beam i n the patient with an abnormal lumbar curve with subsequent incorrect interpretation. Similarly, t i l t of the pelvis correlated with an in-creased mean measurement of the posterior joint subluxation and this may also be due to incorrect centering or may in fact be true in-creased unilateral posterior joint subluxation, in compensation for 152. the pelvic t i l t . It is interesting to note that an increased number of lumbar vertebrae is associated with decreased evidence of posterior joint degeneration, a decreased mean sagittal canal diameter and increased retrospondylolisthesis at the level next above the fusion. The signif-icance of these findings is not known. Noting the additional correlation of Schmorl's nodes with pseudo-arthrosis might indicate a form of tissue weakness which would cer-tainly f i t in with its correlation with abnormalities of curve and increased spondylolysis. This can only be investigated by further prospective work. Finally, the intercorrelations, as expected, of the various degenerative measures of the lumbar spine show only that the measures do not intercorrelate as well as might be expected, particularly with disc narrowing. However, subluxation of the posterior joints and in-creased retrospondylolisthesis do tend to intercorrelate. Techniques require improvement, particularly measurement of posterior joint sub-luxation which requires meticulous technique for accurate assessment. It is difficult to quantify pathological changes in the lumbar spine but essential, in a study such as this, i f variables are to be identified which will discriminate between individuals or groups of patients in the clinical setting. Criteria for discrimination in re-cording must be clear and objective i f they are to become generally useful. Yet this is s t i l l not possible, for example, in determination 153. of the position of the posterior wall of the vertebral canal when measuring the sagittal diameter at the fusion level, and the im-portance of variations in such measurements may remain concealed until the measurements themselves are made easier. 154. DISCUSSION Low back pain has been seen to be a problem of great magnitude. It is common, costly in terms of social and economic disa b i l i t y and distressing to those who suffer i t . As well as i t s direct effects of pain in the low back or limbs and resultant i n a b i l i t y to perform the normal activities of l i f e i t may be associated with weakness and sensory loss. Although much of the time of the orthopaedic surgeon, the internist and the general practitioner i s spent dealing with the problem, the impact on the individual and society does not seem to have been lessened significantly. It has been shown degenerative changes occur even i n the asymp-tomatic patient and these may, in association with certain other known and perhaps unknown factors lead to the development of back-ache i n this individual. When conventional-or unconventional conser-vative treatment has failed lumbar intervertebral fusion i s often considered. It was shown (p 54.) that the indications for lumbar intervertebral fusion may range from narrowed disc space with ver-tebral displacement through certain congenital anomalies such as hemivertebra or sacralization of the lumbar vertebra to ins t a b i l i t y or the in a b i l i t y to find protrusion of a disc at laminectomy for that purpose. The patient who has had a spinal fusion is considered to be at the end of the road as far as treatment i s concerned. A l l he can 155. be offered is further surgery as a hopefully curative procedure i f he has not had pain r e l i e f to that point, yet the result of multiple operations are successively poorer. It was this patient, then, that this study sought to assess. In view of the controversy concerning the causes for disability in the post-fusion patient (p 59.) i t seemed important to collect as much information as possible on each individual. A f a i r c a l l - i n rate was obtained; the i n a b i l i t y to trace 20 of 141 patients was due to lack of current address, a situation only applicable to those not receiving pensions from the Workmen's Com-pensation Board. Hence the overall results might appear to be a l i t t l e worse than one would hope, with 11% unemployed and 60% missing one to two months of work time over the preceding two years due to backache. Although the unemployment rate i s in fact l i t t l e higher than the provincial average of 7.5% at the time of writing, a l l these people were engaged in productive work at the time of their original back "injury" and the economic loss to employee and employer alike i s con-siderable, as pointed out by TROUP and others 1 4 6' 2 6 2 ' 2 6 4 . Similarly, 55% of cases reported that their overall enjoyment of l i f e was s t i l l negatively affected by their condition, in spite of a mean number of 1.98 back operations and a median time off work at the time of fusion of eight to twelve months. In fact, i t has been 146 stated by KOSIAK et al that a speedy return to work i s necessary to promote a good result: i n this study i t was shown a prolonged 156. time for return to work was associated with poorer results of fusion. Of the approximately 300 variables on which an observation was obtained for each patient i t was f e l t that some §f the variables) were closely linked with success or failure of the operation as indicators 6f this)while the remaining variables could be s p l i t into two groups: those correlating with success and those not correlating with success. An index of success was necessary, against which a l l other observa-tions could be compared, as a foundation for our conclusions. The literature has shown a tendency to use pseudoarthrosis as a single criterion for assessing the result of fusion (p 57.) yet the function of the patient would appear to be more important. A single complaint of objective sign rarely serves as an indication for lumbar inter-vertebral fusion and hence cannot be subsequently used as a yard-stick for improvement. Insofar as any physician deals with a pre-senting complaint, then such presenting complaints must be used as 26 a basis for comparison of patients. BJERRING suggested the use of factor analysis based on success-oriented variables as a method for derivation of a success-failure index and the variable selection was based on functional features important to the patient, aiming to represent on the whole non-overlapping complaints which might, how-ever, be represented by more than one variable. It i s interesting to note here that the two variables representing finance had the lowest factor loadings against "success", suggesting that the financial aspect of the problem i s one of the less important to the post-fusion 157. patient with a low back complaint. The purpose of using this factor analysis based largely on the patient's complaints was to eliminate observer error on the part of the examiner. It was of interest that the examiner's review opinion concerning the patient's degree of improvement subsequent to surgery showed a correlation of .94 with the success index, a figure of 1.00 indicating perfect correlation. This opinion was recorded at the time of examination, without the benefit of psychological test results. It was after this method was developed that the prior use of a similar method by NASHOLD and HRUBEC came to light ' . Their use of certain objective data (p 138) to provide a Disability Index is perhaps better suited for their late follow-up of veterans than for the evaluation of factors involved i n operative success because i t focusses less upon the patient's a b i l i t y to function. It is this functional a b i l i t y and the quality of l i f e associated with i t with which we are primarily concerned, regardless of whether any deficiency was present before surgery or i s the result of the operation, due to the effect of surgery or the individual reaction of the patient. Following development of this "success" index two other major groups of variables were considered: those showing a high degree of correlation with "success" and those not thus correlating. By using factor analysis again on those correlating variables the basic fea-tures underlying the result of the operation were unearthed. It was f e l t that i t would be simpler to examine a limited number of factors 158. rather than to try and conceptualize in a non-arithmetical way the events underlying the importance of the 239 variables themselves. The eight factors, as they were numbered during their production and as they were subsequently identified by the experimenters, are lis t e d below. (1) Pain tolerance (2) Non-neuroticism (3) Health-fitness (5) Single operation (8) "Normal"-functioning lumbar spine (12) Root de f i c i t (13) Optimism for self (14) Mobility of self Theise eight orthogonal (totally non-correlating) factors were used for three basic purposes. F i r s t l y , they were used to compare with suggested causes for success or failure of fusion in the l i t e r -ature. Secondly, they were used to provide a feedback to the c l i n i c a l situation to assist in patient evaluation. Thirdly, they were used to determine the design of prospective studies into the causes of low back problems. COMPARATIVE ASSESSMENT OF THE FACTORS. The variation in individual tolerance for pain is a known phe-71 293 nomenon ' , although the underlying features are not well under-159. stood. It has been implicated in fusion failure by BARR et a l 1 6 , among others. Pain tolerance appears to be separate from the problem of neuroticism, also stated in a rather vague and never f u l l y assessed manner to be a cause for failure of f u s i o n 1 6 ' 1 4 8 ' 1^ 3' 2 1 1 ' 2 1 6 ' 2^ 8' 2 6 9 . Emergence of pain tolerance and neuroticism as separate factors implies that, although neurotic patients may have a diminished pain tolerance, there is a phenomenon of pain tolerance variation between people which i s independent of neuroticism. The effects of neuroticism and intelligence are opposite but not overlapping. There may be a bias operative in favour of the i n t e l l i -gent i n our study as they have smaller demands made on their backs occupationally, and this work effect might be reflected in the "success' score. Certainly, the more manual, unskilled job at the time of follow-up is inversely correlated with "success" (correlation: -0.25), while the heavy manual worker i s known to take longer to return to work after a spell of back-related d i s a b i l i t y 2 6 ^ . In stating neuroticism to be associated with a poorer result i t is important to be aware of the nature of measurements of neuroticism. For example, the hypochondriasis scale of the Minnesota Multiphasic 93 Personality Inventory i s an index of bodily complaints : thus ele-vation is part of any physical illness which produces symptoms, i.e. virtual l y any physical illness. Similarly, depression i s a product of physical i l l n e s s , a normal reaction. However, neuroticism as seen here in factor 2 is neuroticism independent of any physical concomitant: 160. a separate factor i n "success". This is in contrast to the view ex-183 pressed by MACNAB who stated that dis a b i l i t y consists of pain and the patient's reaction to i t . Here i t i s shown that in addition to the patient's organic pain-producing pathology and his reaction to i t , there i s also a variable significant amount of neuroticism. Even a schizophrenia T-score over 70 on the M.M.P.I. would be expected in about 3% of a random population by definition and this must be carefully considered before assigning i t a role in the back problem. (However, in this study, 18% of the cases showed a T-score greater than 70 on the Sc scale of the-M.M.P.I. Although the Sc scale score showed no correlation with "success", and hence i s not important as a "success" determinant, i t must be of significance i n the low back pain problem for such a high rate of abnormality to occur.) The health-fitness factor has been described before. Lack of physd'cal health i n the form of muscular unfitness may be associated 148 258 with failure of the operation according to KRAUS as may obesity Although obesity has been shown here to be correlated with the pres-ence of spondylolysis, neither of these two variables alore signif-icantly correlated with "success" at the p < .01 level. Fusion of more than one level i s more commonly associated with 89 158 252 258 failure of the operation ' ' ' and the multiply-operated patient is a particular problem 8 9' 2 1^' 2 1 6 . This may be due to an 215 233 inaccurate diagnosis ' especially i f the level of the operative approach i s inaccurate. 161. Inaccurate preoperative diagnosis may also be responsible for the emergence of the factor "nerve root deficit"; HAKELIUS showed a speedier relief of pain and return to work in patients undergoing 102 discectomy in whom a true disc herniation was found . It was noted in one patient in this study that a long fixation screw passed through the lumen of the spinal canal; although his overall result was fiair he had a marked three-level root deficit. The two factors relating to optimism or ambition, and body mo-bility or flexibility do not find a ready explanation in terms of the body's reaction to the surgery. It can only be stressed again that prospective evaluation with adequate follow-up is the only method which will provide conclusive evidence for involvement of these factors in an etiological role. One factor not found to be of importance in success was the presence of pseudoarthrosis as determined by conventional means. Fea-tures not examined because of lack of documentation or difficulty in standardizing information were operative technique and surgical s k i l l , 233 252 both held to be important ' , particularly by the advocates of each new method of fusion that has been introduced. In approximately two-thirds of these cases, pre-, per- and postoperative details were not available, while no measure of surgical s k i l l can be devised. Surgical s k i l l and operative selection are probably terms which can be used interchangeably. 162. CLINICAL APPLICATIONS Specific findings of this study may find application i n patient management, particularly with regard to examination and assessment. The orthopaedic measures of motion and muscle power are shown to be impure organic measures and the availability of improved, more objective methods should lead to their c l i n i c a l application (p 147). Similarly, of the many radiological abnormalities implicated i n the pathogenesis of low back pain (p 150), only the presence of kissing vertebral spinous processes and an increased lumbosacral angle was shown to correlate 1 with "success". The presence of degenerative disc 216 signs other than kissing vertebral spines, implicated by some ' 233 252 ' , did not correlate either with success or severity of pain (Table 19), nor did correlation of the "generalized disc disease" factor with "success" reach significance. It has been shown that only the more severe radiological changes of degeneration correlate with 152 the incidence of low back pain while these are also occupation-7 152 related ' . In this light limitation of l i a b i l i t y in those with degeneration sometimes claimed by compensation carriers would seem a) to penalize only the occupationally involved person, b) unfairly-on two scores, as his disc degeneration may be re-lated to theoretically compensable) work-related stresses i n i t i a l l y , while degeneration does not subsequently prejudice the results of fusion. Prospective evaluation of radiological abnormalities and the 163. 150 careful evaluation of their predictor value is essential ; the most useful information would be provided by a study including radiological examination and subsequent patient follow-up to identify those abnor-malities predisposing to the development of low back pain. Psychological assessment of the patient with low back pain may be helpful in management. Even in the absence of firmer evidence for an etiological role of psychological abnormality i t seems only prudent to persist further with conservative therapy in the case of a patient with evidence psychological abnormality on, for example, a well-standardized test such as the Minnesota Multiphasic Personality In-ventory. Such a patient should be given support i f off work and should be rehabilitated even to light duties quickly - chronicity of the disease and a slow return to work are both avoidable and should be forestalled 1 4 6' 1 4 7 ' 1 9 6 . PROSPECTIVE STUDIES Three prospective studies are currently envisaged: A PROSPECTIVE, CONTROLLED STUDY OF LOW BACK FUSION145: Patients in whom fusion is considered indicated by current standards would be randomly allotted to a surgical or non-surgical follow-up group. The value of the procedures could be assessed, as could the effect of therapeutic variables which could not be assessed in this study. Predictor features leading to a successful result could be identified. 290 A PROSPECTIVE STUDY OF THE ETIOLOGY OF LOW BACK PAIN : TROUP 164. et a l have suggested that an etiological study of low back pain should be prospective and industrially-based 2 6 2' 2 6^' 2 6 5 . A large prospec-tive industrially-based study i s planned with random subject selection and prospective evaluation of possible predictor variables, whether physical, radiological or psychological, followed by long-term follow-up. Variables selected for evaluation would primarily be those shown in this study to be "success"-related or as representing the "success"-related factors. STUDIES OF THE ROLE OF MUSCLE TENSION IN LOW BACK PAIN AND. DEGENERATIVE LUMBAR DISC DISEASE 2 7 9 3: Mechanical factors are probably the initiators i n lumbar disc disease 1 9 3' 2 6 2 and occupational factors are implicated. Muscle tension might be an additional mechanical fac-tor and has been shown electromyographically to be associated with 6 3 low back pain . The planned study would evaluate the role of muscle tension in low back pain in humans and the modes and effects of i t s therapeutic reductions, and would also study the effects of increased muscle tension on the pathological changes of degeneration in animals. Thus, by studying the various factors prospectively the causal role can either be confirmed or denied. This w i l l permit resolution of the shortcomings of the retrospective approach and w i l l enable continued development of the theories highlighted in this work. 165. SUMMARY A follow-up study of 100 patients, who had a l l undergone lumbar vertebral fusion at least two years previously and were subjected to detailed h i s t o r i c a l , social, physical, radiological and psychological assessment, i s reported. The report is based completely on the post-fusion, follow-up findings, as recorded preoperative findings were not uniform and hence not used. Factor analytic methods were used to derive an index of success, based on the patient's current function, which was used as the major dependent variable i n the formation of a correlation matrix of the majority of the variables. Using 55 variables, a l l highly "success"-correlated, further factor analysis was performed to identify factors closely associated with success or failure of the fusion operation. Particular attention was also given to the orthopaedic and radio-logical methods of patient assessment. Testing the hypotheses, the purpose of the study was: 1) To establish the multifactorial etiology for continued disab i l i t y following lumbar intervertebral fusion. 2) To identify patient characteristics l i k e l y to be asso-ciated with success or failure of the operation. 3) To identify variables for further investigation of the etiology of low back pain disease. 166. CONCLUSIONS 1. Lumbar intervertebral fusion may bring complete pain r e l i e f (in 17% of cases) and return to a productive l i f e to some patients (40%), but 60% s t i l l . s u f f e r marked disability. 2. The success of lumbar intervertebral fusion, as determined by patient function, is associated with eight f a i r l y well-defined factors, representing different aspects of physical and psycho-logical health and disease. These were identified thus: (in order of importance) Normal-functioning lumbar spine Mobility of body Freedom from neuroticism Pain tolerance Minimum number of surgical operations Freedom from persistent nerve root d e f i c i t Optimism, ambition General health and fitness. These independently accounted for approximately 80% of the variance of "success" as determined by s t a t i s t i c a l means. This means, in practical terms, that the patient with a good result from a functional viewpoint w i l l have a normal lumbar spine on examination, a b i l i t y to move freely, w i l l not be 167. neurotic and w i l l have a good tolerance of pain. He w i l l prob-ably have had a single operation, w i l l be free from symptoms ascribable to a nerve root d e f i c i t , w i l l be optimistic and ambitious, and w i l l be i n good general health. The patient with a poor result w i l l manifest the opposite features. 3. Radiological evidence of failure of bony fusion (pseudoarthrosis) at the site of operation does not correlate significantly with success or failure of the surgical procedure of lumbar inter-vertebral fusion. This may be due to the inadequacy of radio-logical diagnosis or to the fact that r e l i e f of dis a b i l i t y is not dependent on production of bony fusion. 4. Orthopaedic methods of patient assessment are relatively in-accurate measures of organic impairment, reflecting to a large extent the patient's psychological state, and more objective, quantifiable measures should be employed. This is particularly necessary in assessing motion of the lumbar spine. 5. Radiological methods of assessment of the lumbar spine are dif-f i c u l t to quantify and require better standardisation. 6. Psychological evaluation of the patient with a low back pain problem can provide useful information in the overall management of that problem, at any stage, including preoperatively. 7. This retrospective study of low back pain does not allow assign-168. merit of etiological roles to the indentified factors, but has demonstrated the practicability of the methods employed and indicated the directions for prospective studies. 169. Superior articular process Transverse process Spinous process Inferior articular process Spinous process Superior articular process . Inferior articular process Transverse process Vertebral canal Figure 1: The Lumbar Vertebra 170. Group 1 Group 2 - Group 3 Fif^ure 2; Mean MMPI p r o f i l e s of the three outcome groups« p i l o t study. 171. Retrospondylo-listhesis Anterior vertebral body height Anterior disc height Posterior disc height Posterior joint subluxation Lumbosacral angle Figure 3: Radiological measurements on the lateral view. 172. Figure 4: MVIPI profiles by "success" quartiles - main phase Overall mean ........ Highest quartile . ,.. Mid quartiles (2) _ Lowest quartile TABLE 1 BIOCHEMICAL DISC CHANGES WITH AGE AO DEGHtRATIOii AFTER iWLOR-D i s c c o n s t i t u e n t D i s c d e g e n e r a t i o n D i s c p r o l a p s e 1) M u c o p o l y s a c c h a r i d e s k e r a t a n s u l f a t e f r a c t i o n s (N) t o t a l , p r e d o m i n a n t l y k e r a t a n s u l f a t e (N) 2) G l y c o p r o t e i n s s u g a r m o i e t y s u g a r m o i e t y (N § A ) due t o d e g r a d a t i o n o f g l y c o p r o t e i n s 3) C o l l a g e n f i b r i l l a t i o n - f i b r i l l a t e d ; immature t y p e (N) (A) 4) N o n - c o l l a g e n o u s p r o t e i n s appearance o f B - p r o t e i n B - p r o t e i n CN) p r e m a t u r e l y (A) 5) Water ? 6) pH shows no change i n e i t h e r c o n d i t i o n N = n u c l e u s A = a n n u l u s TABLE 2 RESULTS OF DISCECTOMY A u t h o r Number o f F o l l o w - u p . R e s u l t Employment p a t i e n t s t i m e S a t i s f a c t o r y U n s a t i s f a c t o r y Same o r L i g h t e r o r Unemployed e x c e l l e n t good f a i r w o r s e o r h e a v i e r h a n d i c a p p e d same o r p o o r A I T K E N 2 a) 211 15% 2.5% 20% 11% 38% 25% 34% 49% b) 200 2 - 5 y r s 25% 14% 20% 12% 21% 33% 26% ' 47% 33% 47% BARR e t a l 1 5 380 92% 29 B o s o r 1351 33% 33% 44% GURDJIAN e t a l 1 0 1 915 3 - 1 3 y r s 19.9% 21.4% 17.9% 20.8% 16.3% 53.6% 57.1% 48.8% 55.7% 45 .1% 19.7% 6.7% 15.4% 6.0% 25.6% 7.7% 18 .1% 3.6% 26 .1% 12.4% 1(12 HAKELIUS 138 . ?30% 88% 1% 177 MOYES 218 86% 194 NACHLAS 374 > 5 y r s 60% NASHOLD /HRUBEC 1 9 6 C.300 20 y r s 23.3% 69% 7.7% 243 SIMON 25 60% 28% 12% WHITE, A . W . M . 2 7 5 119 > 2 y r s < 40$ WHITE , J . C . 2 7 6 130 o f 380 33% 42% 14% 11% 79% . 11% 10% (same p a t i e n t s as BARR) s e e n p e r s o n a l l y TABLE 3 FUSION PROCEDURES AiW THEIR ORIGINATORS Fusion type Probable originators Date Features Complications Interspinous Posterior arch Clothespin, H-graft Posterior bone with plate fixation . Posterolateral Transfacet screws Albee Henle Hibbs Gibson Bosworth Straub Wilson and Straub Williams Hibbs Campbell Watkins Adkins Tourney King Arch-body screws Boucher Anterior interbody Capener Speed Mercer Posterior interbody Jaslow Wiltberger 1911 1911 1911 1931 1942 1949 1952 1950 1911 1939 1953 1955 1943 1944 1959 1932 1938 1936 1946 1957 Split spinous process, t i b i a l graft Graft on each side of spinous process Interleaving scales on laminae Tibial 'clothespin' locked between spines Iliac 'H'-graft locked between spines Paraspinal metal plate + matching graft securing spinous processes Twin plates securing spinous processes Posterior arch extended to include transverse pro-cesses Intertransverse fusion alone Short transfacet screws for early fixation of vertebrae; posterior bone grafting Long screw from posterior arch to body below, posterior bone grafting Anterior t i b i a l graft Donor site pain, esp. i f outer i l i a c cortex used Nerve root irritation Nerve root irritation High pseudarthrosis rate sexual malfunction Iliac crest bone Posterior discectomy and bone-grafting Posterior 'dowi' graft insertion TABLE 4 fflFPARATIVE RESULTS OF REPORTED FUSION SERIES SENIOR AUTHOR NUMBER IN O v e r a l l R e s u l t s % O v e r a l l F u s i o n r a t e F u s i o n t y p e SERIES Good F a i r P o o r S o l i d P s e u d o -a r t h r o s i s BOUCHER 3 0 234 971 34 - - P o s t e r i o r - l o n g s c r e w f i x a t i o n CALANDRUCCIO 4 1 16 561 444 384 624 A n t e r i o r i n t e r b o d y C L E V E L A N D 4 6 598 9 4 . 8 1 1 5 . 2 4 83 .54 1 6 . 5 4 -DE P A L M A 6 0 78 591 274 144 M a t c h e d p a i r s o f e a c h -DOMMISSE 6 5 48 811 114 84 584 42% P o s t e r i o r i n t e r b o d y K I N G 1 4 0 44 904 104 914 94 T r a n s f a c e t s c r e w f i x a t i o n 153 LEVY 250 784 134 94 - - -159 LUCAS 17 59% 414 944 64 M e u r i g W i l l i a m s p l a t e s M A C N A B 1 8 5 - 366 - - - 824 184 S e v e r a l , compared 207 PENNAL 150 - -- - 834 174 P o s t e r i o r - l o n g s c r e w f i x a t i o n P R O T H E R O 2 1 1 430 - • - - 84 .94 1 5 . 1 4 P o s t e r i o r + p o s t e r o l a t e r a l R A N E Y 2 1 5 4 3 / 4 6 514 124 374 834 174 A n t e r i o r i n t e r b o d y ( s a l v a g e ) R A N E Y 2 1 6 139 464 224 324 804 204 A n t e r i o r i n t e r b o d y ( s a l v a g e ) S T I N C H F I E L D 2 5 2 100 - . - - 944 64 H - g r a f t T H O M P S O N 2 5 8 1096 - - - 8 3 . 4 4 ' 1 6 . 6 4 H i b b s 1 7 7 . TABLE 5 SCORING CRITERIA FOR PATIENT GROUPING/ PILOT STUDY TITLE SCORE Drop in employment 1 or Cessation of employment because of low back symptoms 3 Presence of pain 2 Time lost in last two years 2 Impairment of gait 2 Low back tenderness 2 Range of flexion 2 Range of extension 2 Range of lateral flexion, left 1 Range of lateral flexion, right 1 Straight leg raising 2 Patient's opinion of results 2 Patient's opinion of value of surgery 2 Opinion of examiner 4 TABLE 6 ORTHOPAEDIC ASSESSMENT OF PSYCHOLOGICAL PARAMETERS (%) TEST 1 2 3 4 5 6 7 8 9 10 Score Extro-version Indepen-dency Passive Aggres-siveness Dominance Eagerness to Recount Troubles Emotion-a l i t y About Troubles Anxiety over Doctor-Patien t Relationship Anxiety about h i s pathology Verbal A b i l i t y I.Q. Low 1 0 0 5 2 0 2 3 3 3 1 2 12 7 28 13 6 11 19 10 15 o o 18 ' 3 19 24 15 42 15 25 24 28 42 36 4 14 12 19 20 20 24 24 18 33 31 5 31 27 21 17 33 29 27 25 6 13 6 16 27 9 6 22 8 3 14 0 0 High 7 8 3 3 0 4 1 0 2 1 1 179. TABLE 7 MEASUREJWS OF VERTEBRAL BODY HEIGHT Vertebral Body Minimum Maximum Mean S.D. L l Front 25 39 33.95 2.59 Rear 30 43 36.97 2.31 L2 Front 22 41 35.78 2.72 Rear 31 44 37.27 2.38 L3 Front 31 44 37.34 2.48 Rear 30 44 37.24 2.72 L4 Front 25 44 37.05 2.81 Rear 28 44 35.94 2.92 L5 Front 33 46 38.01 2.62 Rear 27 42 32.40 3.02 Mean ('Bodymean') 35.84 2.06 180. TABLE 8 EASURBWS OF INTERVERTEBRAL DISC HEIGHT Intervertebral disc Minimum Maximum Mean S.D. Ll-2 Front 7 16 10.74 1.97 Rear 2 11 6.87 1.62 L2-3 Front 7 20 12.47 2.12 Rear 4 13 7.77 1.78 L3-4 Front 5 19 13.38 2.58 Rear 2 13 7.93 1.86 L4-5 Front 4 21 12.44 4.08 Rear 1 11 7.12 2.20 L5S1 Front 4 18 11.05 4.11 Rear 2 8 4.82 1.62 Mean ('Discmean') 9.34 1.51 N.B. Measurements of disc height were standardised relative to the appropriate level for use in correlations as 'Discnext': the height of the disc at the level above the fused level. 181. TABLE 9 EASURLWTS OF POSTERIOR JOINT SUBLUXATION Joint level Minimum Maximum Mean S.D. Ll-2 0 12 1.73 2.10 L2-3 0 10 1.90 2.09 L3-4 0 9 2.46 2.35 L4-5 0 10 4.02 2.37 Mean ('Luxmean') 2.09 1.68 N.B. For correlation purposes, positive and negative values of posterior joint subluxation were used and standardised relative to the appropriate level for 'Luxnext', the degree of posterior joint subluxation at the level next above the fused level. 182. TABLE 10 EASueers OF RLTROSPONDYLOLISTFESIS Joint level Minimum Maximum Mean S.D. Ll-2 0 12 0.99 0.97 L2-3 0 10 1.62 1.07 L3-4 0 5 1.65 1.12 L4-5 0 6 1.57 1.46 Mean ('Retroavg') 1.17 0.70 N.B. For correlation purposes, positive and negative values of retrospondylolisthesis were used and standardised, relative to the appropriate level for 'Retronex', the degree of retrospondy-lolisthesis at the level next above the fused level. 183. TABLE 11 EASUREEi^ S OF WERPffilCULAR DISTANCE Vertebral Level Minimum L l 22 L2 21 L3 23 L4 25 L5 28 Mean ('Ipedavg') Maximum Mean S.D. 34 27.37 2.05 33 27.55 2.19 34 28.67 2.21 38 29.92 2.57 41 31.31 3.34 27.98 2.05 184. TABLE 12 i^UREMS OF SAGITTAL DI AMEER OF VERTEBRAL CANAL Vertebral Level Minimum Maximum Mean S.D. L l 17 27 22.81 1.97 L2 17 29 22.00 1.99 L3 16 27 20.66 2.13 L4 15 28 19.60 2.57 L5 14 21 18.00 2.74 L6 (where relevant) 16 24 20.00 5.66 Mean ('Sagmean') 20.93 1.87 186. TABLE R FACTOR MATRIX FROM ''SUCCESS''-CORRELATII« VARIABLES; CORRELATION OF FACTORS AGAIiMST "SUCCESS" (FIRST TWO POST-DECIMAL FIGURES/ ROUNDED OFF.) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Y A S I A 3 I . 2 C ? T 31 1 1 - 0 4 01 -02 - 1 2 02 0 8 0 7 02 15 -03 05 0 4 0 6 07 0 3 CILU.1 - 1 5 - 1 4 - 1 3 - 2 0 1 9 -OS - 3 2 2 4 - 0 4 03 1 6 - 1 8 - 4 1 02 -co -05 1 7 74 01 34 16 -02 - 1 4 -01 11 0 8 0 1 0 2 03 1:! 10 - 0 8 TAI-O-I -10 - 7 1 - 0 7 - 4 7 -03 0 9 0> -12 0 7 02 - 1 0 0 6 - 0 7 01 0 8 00 13 NI?IHS - 0 4 -74 - 1 8 0 5 - 2 4 0 6 17 - 2 2 0 6 -02 0 0 - 0 1 0 1 01 - 1 6 -12 -12 -02 - 7 6 - 1 8 3 2 -23 0 6 19 - 1 3 0 7 - 0 3 0 7 - 0 4 - 0 2 - 0 7 - 1 2 - 0 7 - 0 4 B3C:< - 1 1 - 7 6 -01 - 1 6 - 1 4 1 4 -01 -21 - 1 1 - 0 7 0 6 2 2 - 0 5 0 4 0 4 - 1 0 1 1 0 4 -7a' -20 - 1 1 -03 01 10 -13 - 0 7 - 0 6 - 0 4 00 - 1 1 -03 - 1 2 - 0 5 - 1 8 H K F 1 P T 0 3 - 8 1 0 6 - 1 4 - 0 4 0 6 -01 -01 0 0 ' 09 - 1 1 - 0 2 - 1 1 - 0 7 0 0 - 0 1 0 2 S T T P ? - 1 5 -05 -37 - 1 9 - 2 2 35 09 0 3 0 6 - 0 4 - 2 4 0 9 - 1 2 -31 - 1 2 - 2 6 1 0 L E G S 01 - 1 3 -» -03 -01 3 6 13 - 0 7 05 - 1 7 - 0 8 23 - 1 6 - 0 4 - 0 4 -50 - 0 6 TO:T - 2 ? 01 -57 0 7 01 - 0 5 OS -38 - 1 3 - 0 6 2 6 1 0 15 09 0 6 - 1 8 -03 02 -20 - 7 4 -06 - 0 3 - 0 7 13 - 0 4 - 1 1 03 -00 3 0 - 0 1 -21 05 - 1 6 0 4 S S T S A T 1 3 -15 - 7 8 -02 - 0 3 10 - 0 3 - 0 6 02 0 8 - 2 0 - 1 7 -03 - 1 8 - 2 0 1 2 03 C P 1 C 3 0 8 21 -01 79 -05 1 1 01 16 01 - 1 6 2 0 - 0 2 0 1 0 9 0 1 0 1 0 4 C P I S P -07 29 05 75 0 6 0 7 - 0 3 0 7 0 9 0 4 - 2 0 0 7 12 0 4 15 - 0 1 15 1SDFI.EX -30 - 0 2 -38 2 2 -43 0 7 - 0 6 - 1 7 0 5 - 0 4 0 7 - 2 0 1 8 -13 0 7 -09 1 8 U K : O 13 -09 - 0 7 -20 - 6 1 0 6 - 0 7 - 1 6 10 - 0 4 - 0 9 3 4 1 5 0 7 1 7 -?3 0 0 FUSIOSO - 0 7 - 3 2 - 0 3 03 - 7 3 1 3 0 4 - 1 6 -10 0 7 - 0 7 - 0 6 - 1 7 - 0 2 - 0 7 00 - 1 4 0 P K U T 5 -02 -35 02 05 - 7 9 - 0 1 16 -12 - 1 1 -03 - 0 8 0 3 - 2 0 . - 0 7 05 0 1 - 0 1 -21 - 0 0 ' 0 0 11 - 0 9 8 0 - 01 - 0 4 -02 05 0 2 0 4 03 - 1 1 - 1 1 0 1 -03 BaCKS • 05 - 2 6 - 0 7 0 5 01 7 6 03 - 1 3 -01 01 -03 - 1 0 - 2 1 05 - 0 6 - 1 0 - 0 3 OBI?CH - 0 0 - 1 3 - 0 7 - 0 4 - 0 9 02 55 - 1 8 -01 - 0 7 - O J 03 -03 - 1 1 -03 0 4 - 1 0 C m ^Pft 01 - 3 3 -02 - 0 6 01 0 5 74 -20 - 0 5 0 4 - 0 4 0 8 - 0 9 - 2 6 0 1 -:e 02 H T P 2 I 3 C T - 1 9 -37' -01 -12 - 1 1 13 17 - 4 2 -12 16 0 2 2 7 - 1 0 -21 - 3 8 0 3 11 ABDPO'./A . - i o . 1 9 - 0 3 - 1 8 - 0 7 - 1 8 2 8 -45 21 07 1 7 15 - 4 2 1 3 -25 00 - 1 3 LOK3CT . 10 - 2 4 -25 - 1 5 -16 2 8 -03 -47 - 1 3 - 2 7 -24 0 4 23 - 0 8 -03 22 -11 0 5 0 7 - 2 2 - 2 2 - 3 2 2 9 13 - 4 9 -25 -21 - 0 1 1 3 0 9 - 0 9 0 8 1 1 1 7 S L R -32. -02 -23 -19 - 1 1 -05 16 -51 - 0 4 - 0 8 - 2 9 20 - 1 1 - 0 6 - 0 2 - 1 3 0 4 oB j a r r - 1 7 -32 - 2 8 06 -27 12 15 -54 - 0 6 -03 - 0 9 1 8 - 2 3 - 1 8 - 0 4 - 0 4 0 7 S P A S M 1 1 -15 20 0 0 - 1 1 29 2 8 -57 -03 -03 - 0 4 -01 -12 -03 - 1 9 02 0 4 ABBPOVB - 1 5 - 0 8 -05 -02 -03 1 6 1 9 -58 - 0 7 -10 2 8 1 7 - 1 9 -3« - 1 4 02 0 5 C A S S I S ! ! 0 6 -23 15 02 0 4 - > 3 17 - 6 0 - 2 2 0 4 - 0 4 20 0 8 03 - 2 8 - 2 6 -15 BACEPOK - 2 1 - 3 1 - 1 6 - 0 4 -05 0 4 -12 - 6 9 -12 -02 1 1 ' ' 11 - 1 2 - 1 7 -05 - 0 8 - 1 5 f l B t T W O -05 - 1 4 . -09 - 1 3 -21 -02 . 06 - 7 6 1 4 - 0 6 - 0 9 -06 - 0 6 - 1 8 0 4 -03 16 CATIQ 10- 0 4 02 1 6 16 - 1 9 - 0 6 15 73 09 05 - 0 4 - 1 7 0 8 1 9 • i o . - 0 2 H Z A 3 A C H Z ' -03 - 4 2 -01 - 0 8 -10 4 0 05 -10 5 ? -09 0 9 ' 0 9 0 8 -10 1 2 0 0 - 1 0 BP -02 - 1 8 - 1 4 03 - 0 0 - 0 8 02 - 0 9 -69 02 - 0 6 0 8 - 3 4 - 0 4 2 8 1 0 - 1 1 P A t r a r a 03 -20 - 0 0 0 9 - 1 3 2 2 -12 -36 - 1 5 47 0 2 2 2 1 6 -23 -25 - 1 4 - 1 8 STA.-1CE - 0 6 - 1 6 - 0 0 1 1 - 0 8 0 4 " 3 - 1 9 - 0 7 - 8 2 03 0 7 0 5 - 1 1 - 1 3 - 1 6 -07 B E T 0 R 5 - 3 6 - 2 8 01 - 0 9 - 2 8 02 2 2 - 0 8 - 2 4 -01 3 6 0 4 - 0 2 - 2 1 -15 0 2 3 0 8 0 V - 1 9 T12 - 0 9 -05 - 1 7 02 15 - 0 7 - 1 5 01 - 7 6 0 1 0 8 - 0 5 - 0 6 - 1 7 - 0 4 I H S P O V - 0 6 -02 - 0 7 0 8 -02 -05 03 -21 - 0 5 - 0 5 0 1 7 8 - 1 0 - 1 8 - 0 8 O f 0 1 WALnra; - 1 1 - 1 7 - 1 3 - 2 8 - 2 8 1 7 12 -05 - 0 4 4 6 0 6 4 9 13 0 5 1 1 - 0 7 - 2 2 i c n w 13 47 - 0 2 02 10 - 1 6 - 0 7 13 0 7 09 05 - 1 1 6 1 10. - 0 1 - 0 3 0 3 fCPCT - 0 0 23 -03 1 8 1 9 -21 - 0 4 1 9 0 6 - 0 6 - 1 7 -05 5 9 12 0 7 2 7 0 7 CAR - 2 7 - 1 8 -20 - 1 4 - 0 7 02 25 -36 - 1 1 ' 0 6 1 1 - 1 1 - 2 8 - 4 0 - 1 6 0 1 0 8 L i P T i i r o 1 7 - 0 6 -12 -02 0 3 -01 0 9 - 4 4 - 0 6 . 1 7 - 1 9 1 1 0 9 - 5 8 0 4 -23 - 0 2 L0'.3ACK - 1 5 -12 -oe -15 0 6 0 6 0 8 -23 - 0 0 - 1 3 0 6 - 0 6 0 2 - 6 0 - 1 1 -32 15 B E S 3 I N C - 0 6 -03 -23 03 -13 05 23 - 0 9 - 0 6 -10 -05 2 4 -13 - 6 ) - 0 2 03 . - 1 8 R E C T A L -03 - 0 9 02 -20 -43 - 0 7 -37 - 1 5 0 5 - 0 6 - 0 1 1 4 0 1 - 1 5 - 4 9 1 0 - 0 4 I H T 2 3 C A P - 0 7 - 1 7 - 1 4 - 0 7 1 8 2 4 0 8 - 1 7 - 0 3 -13 - 0 4 0 1 - 0 7 -03 - 7 5 - 0 8 -03 BCTTOCE - 0 9 - 1 7 -10 0 3 - 0 8 03 03 - 0 7 -02 - 0 6 - 1 4 - 0 8 -05 - 1 8 - 0 2 -70 0 2 T A L C A L V A •111 -10 -11 -07 - 0 8 00 13 -33 0 4 1 4 - 1 6 3 9 -25 - 0 2 - 2 6 0 5 4 6 S I B S - 0 8 - 0 8 05 -32 - 1 6 11 2 2 0 0 -01 0 4 - 1 2 0 9 - 2 1 - 0 7 -13 0 6 -59 8 B C C S 3 3 28 34 21 14 25 -15 -U 49 07 06 02 -22 22 40 14 10 01 187. TABLE 15 INSCRIPTION OF THE 17 "SUCCESS''-RELATFiJ FACTORS, THEIR CORRELATION WITH "SUCCESS" AND THE VARIANCE OF "SUCCESS" ACOQUNTED FOR (SEE TABLE 14 FOR FACTOR LOADINGS) F a c t o r D e s c r i p t i o n C o r r e l a t i o n P= 1 v a r i a n c e Number c o e f f i c i e n t o f " s u c c e s s 1 8 N o r m a l b a c k o r t h o p a e d i c a l l y + 0 . 4 8 5 1 .0000 2 3 . 5 3 14 M o b i l i t y o f s e l f + 0 . 3 9 7 3 . 0 0 0 1 1 5 . 7 8 2 N o n - n e u r o t i c i s m + 0 .3352 .0008 1 2 . 3 9 1 P a i n t o l e r a n c e + 0 . 2 8 2 1 .0045 7 . 9 6 5 S i n g l e o p e r a t i o n ( v s . m u l t i p l e ) * 0.-2502 .0116 6 . 2 6 12 R o o t d e f i c i t - 0 . 2 1 8 9 . 0 2 7 1 4 . 7 9 13 O p t i m i s m f o r s e l f + 0 . 2 1 8 7 . 0 2 7 3 4 . 7 8 3 H e a l t h - f i t n e s s + 0 . 2 1 1 5 .0327 4 . 4 7 % v a r i a n c e a c c o u n t e d f o r b y f a c t o r s s h o w i n g s i g n i f i c a n t s u c c e s s -c o r r e l a t i o n (p < .05 ) 7 9 . 9 6 6 G e n e r a l i s e d d i s c d i s e a s e - 0 . 1 4 8 4 . 1 3 6 4 2 . 2 0 4 S o c i a l competence + 0 . 1 4 3 8 .1494 2 . 0 7 15 + 0 .1362 . 1731 1 .86 7 O r t h o p a e d i c p s y c h o l o g y - 0 . 1 0 6 0 .2940 1 .12 16 1 + 0 . 1 0 0 4 .3217 1 . 0 1 9 1 + 0 . 0 6 5 7 . 5232 0 . 4 3 10 P o s t u r a l + 0 . 0 6 4 2 . 5 3 3 3 0 . 4 1 11 1 + 0 . 0 1 7 4 . 8402 0 . 0 3 17 1 + 0 .0149 . 8552 0 . 0 2 O v e r a l l % v a r i a n c e o f " s u c c e s s " a c c o u n t e d f o r by t h e 17 f a c t o r s 8 9 . 1 1 ? s i g n i f i e s u n i d e n t i f i a b l e f a c t o r . 188. TABLE 16 LOADINGS OF THE i^ ASHOLD MJ.HRUBEC DISABILITY -INDEX 1 Atrophy of legs 22 2 Weakness of legs 48 3 Decreased sensation 44 4 Decreased reflexes 21 5 Loss of lordosis 42 6 Restricted motion 39 7 SLR test 42 8 Changes i n occupation history 15 9 Limitation - back pain 65 10 Limitation - back weakness 30 11 Limited use of legs 68 12 Handicap in employment 76 13 Functional evaluation 76 14 Complaint of back pain 51 15 Complaint of leg pain 50 16 Change in employment 47 17 O.A. compensation 45 18 Subsequent surgery for herniated nucleus pulposus 21 189. TABLE W, PSYCHOLOGICAL SCORES ON 4 PARAMETERS BY QUARTILE GROUPING Upper Middle (2) Lower "Success" I.Q. Beck Taylor 1.16 87.88 4.29 13.76 0.10 83.32 7.44 18.22 -1.36 78.20 13.00 24.09 190. saraswr K? * . . . . . . . A C S - - J FUSI05D i i 2 8 22 7? t TABLE 18 C A T M 2 8 22 4 2 - - J B S C S i2 37 37 - - 22 * !!KPinS i O - 1+7 - - 12 6 0 S T A Y L O R W> - - 27 2?' - 7 0 J O t T I L T . . . . . . . . . . t C o r r e l a t i o n mat r ix o f c e r t a i n o r thoped ic L 0 K F L 2 I . - 3 3 — — $ examinat ion methods w i t h the " s u c c e s s " F L E X T O O 52 i2 - 3* 2 7 - 32 36 2 8 35 - t L U K O T 4 6 W 25 2 6 32-22 32 36 32 - - ' 5 1 8 _ l n d e X ' C C T t a i " P " * " * 0 1 0 ^ 1 a c d r a d i o l o g i c a l PAISEXT i2 53 - - 4 1 22 35 36 - .- - - 35 S v a r i a b l e s . A l l c o e f f i c i e n t s shown reach S T P E S H T 80 6 2 l 3? 38 2 2 58 4 2 4 2 54 22-54 36 74 S ' s i g n i f ioance ( p < .05 ). R I F L E * i2 32 39 31 31 4 1 27 22 - 35 22 53 6 1 - 4 1 J . . X » c o r r e l a t i o n , p < . 1 H E I T S I _ 3 t <8 64 - . 3 3 2§ 5 1 44 2 8 51 - 6 1 5 8 83 73 47 J T E C T S R 2^ 5 5 - T - J l 3 8 2 6 22 - - 5 6 43 65 7 1 4 1 9 1 J P V T O h G J l 58 - 56 4 8 - 63 6 3 36 - - -50 5 9 5 « 5 0 7 0 74 7 1 8 M 3 T C R 3 X J I B D P O ' J B 72 5 8 - 2 4 - 2 8 34 34 - 52 3 3 68 44 49 69 5 1 5 8 7 8 . 5 0 - ' S . 3 A C Z P 0 V 80 70 - 30 37 26 54 50 3 8 ' - - 8 1 57.61 6 7 52 7 8 8 1 56 - 8 0 S ' S L R 6 8 4 7 - 3 4 2 9 2 8 31 2 4 30 - - 6 6 44 36 5 1 4 2 6 1 58 5 8 5 2 4J 59 3 ' i n S T E . . . . . . . . . . . . . . . . L 3 5 P C V 4 6 - - - - - 29 - - - - - - 4 8 43 34 5} 49 56 - 4 8 39 4 1 - ' f » rjTRXlSE . . . 3 * 3 3 . . . . . . . . . . . . . . X - - - - J 3 S ' 3 S B A O C - 25 • X 3 3 2 7 - 2 8 3 1 29 - - - - - - 30 - - - - • - - - - - - 0":t L 0 S S R 1 2 6 - - . - - - 3 4 - 4 2 . . - 4 5 4 6 3 ' - - - • - - - 44 - - X - - « C T T 3 4 - i 4 r - 2 J 22- - - - - - - - 22- - - . 4 1 - - 2 4 - - - . - $ " L Y S I S - J P O R O S I S - - X . - - - - - - I . . . . . . . . . . . . . . . . . . . t D Y E X - - 25 - - - - - - - - - - - 36 - - 6 4 . - - 33 22 *3 - - - - - -$ L E V S L A 2 6 2 8 - 4 1 38 - 29 32 25 - - - 44- 35 - - - 6 7 - - - - - - - - - - - 57 - 8 S O L I D . - - 2 0 - - - - - - - . . - . - - . - - - - - - - - - - - 12 36 8 S C R 5 W 3 - - - - . - - - - - - - - - - - - - - - - . - - - - - - - . - - . - - I 3 E G S H . - - - - - - - - - - - - - - - - - - - - - - 2 J - - - - - - . - - - - - - I S P U R S - - 30 - - 2 4 . . . . . . 53 - - X - - 4 4 - - . . . . . . 2 8 - S OSTi-DPltY - - 5 6 - - 35 25 - '27 - - - 4 3 - - 38 - - . - - - - - - - • - 3 7 39 - - - - - - - - 4 8 ft' 3 A A S T K U P 2 4 - 32 . . . 25 2 8 26 - - - - - - - - - - - - - - - - - - - - - - - - - - 31 X 4 2 8 D I S C H 3 A H - - 3 5 - 3 J Z - - 2 6 - - - $ . 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X » correlation, p < .1 •52 37 37 J a - - 7 0 I s . . . . . . ft; I i i 37 30 28 - X - » a - s i * - - - - - 60*. - - •*' X - - - I su x" - . - - » ' - - - - - - X . - - - - S - - X - - 60 . . X . . X . . - S X - - - - X - - - - - - - - - J - . . . 36 I 28 28 - 29 25 - - *1 - - X - - 57 - - - t 1 2 - . . . . 36 I - • - - X - - - 3 * j. - - - - - T 77! M . . n x » - - i ' - - - 53 80 -- - - - - 59 63 - - - - - - - S - ' - 30 - - - - - - 2 8 - ' - - • ' . J - - 56 25 27 . . . . . . . . . . . . . . - - - - - - 1.8 » - - - - 69 » 2j» - 32 25 26 - 31 X 42 - ' J 20 22 24 20 - 26 - - - X - - 55 - - - - - . - - - ! • > - - - - X - I X 22 35 35 - - - 32 26 . . . . . J . - 30 - - - - 32 - 39 - - 3 2 - . - - - _ 3 H 3 6 - 2 7 . - l 5 8 5 _ Z - - - - - - - - 3 £ i l - - 27 35 2< t - - 3 2 » - - 2 0 - - - W 1 - - - X . X - - - - - 3 1 - - - - - . X - - . - - - I 22 - - 27 2 2 - X - - - - . - - - X . . . 5 5 $ . . . . . . 32 - . X X . . - - - - - - - - - - - - - - - 21 26 I - - - - - - - - - - - - - 3 2 - - . J40 21 - - - - - - -1 - - X 77 - - - - - I . - ] 2 - . - . X - 2 » - . - . . - - 2 6 . . . - - . . 2 < . . . . 7 f > 3 » - - . . | - - - X - 2 8 - - 1 2 - 33 M - •- . . . . . . . . 3 7 - - - - ja-- - - - M l b !2 M ? u, *• £ G- H 1 192. BIBLIOGRAPHY 1. AHLGREN, E.W., STEPHEN, CR., LLOYD, A.C. and MCCOLLUM, D.E.: Diagnosis of Pain using a Graduated Spinal Block Technic. JAMA. 195: 813-816, 1966. 2. AITKEN, A.P. : Rupture of the Intervertebral Disc in Industry: Further observations on the end-results. Amer. J. Surg. 84: 261-267, 1952. 3. ALLBROOK, D : Movements of the Lumbar Spinal Column. J. Bone Joint Surg. 39B: 339-345, 1957. 4. AMATO, V.P., BOMBELLI, R.: The Normal Vascular Supply of the Vertebral Column i n the Growing Rabbit. J. Bone Joint Surg. 41B: 782-795, 1959. 5. AMELAR, R.D., and DUBIN, L.: Impotence i n the Low-back Syndrome. JAMA. 216: 520, 1971. 6. 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WHITE, A.W. 276. WHITE, J.C. M. M. The Compensation Back. 871-874, 1966. Applied Therapeutics. 8: Low Back Pain in Men Receiving Workmen's Com-pensation - a Followup Study. Canadian Medical Association Journal.. 101: 61-67, 1969. Results i n Surgical Treatment of Herniated Lumbar Intervertebral Discs: Investigation of the Late Results in Subjects with and without Spinal Fusion - A Preliminary Report. C l i n i c a l Neuro-surgery. 13: 42-54, 1966. 277. WILEY, J.J., MACNAB, I., and WORTZMAN, G.: Lumbar Discography and i t s C l i n i c a l Application. Canadian Journal of Surgery. 11: 280-289, 1968. 278. WILEY, A.M. and TRUETA, J.: The Vascular Anatomy of the Spine and i t s Relationship to Pyogenic Vertebral Osteo-myelitis. J. Bone Joint Surg. 41B: 796-809, 1959. 279. WILFLING, F.J. : A Psychological Follow-up of 100 Post-fusion Patients. Thesis i n Preparation. Vancouver. 1972. 216. 279a. WILFLING, F.J., and WING, P.C.: The Pathogenesis of Low Back Pain: Experimental Research Proposal. Vancouver. Ortho-pedic and Trauma Research Unit, University of British Columbia. 1972. 280. WILLIAMS, P.C. : The Lumbosacral Spine. New York. McGraw-Hill Book Company. 1965. 281. WILLIS, T.A. : Backward Displacement of the Fifth Lumbar Vertebra: an Optical Illusion. J. Bone Joint Surg. 17: 347-352, 1935. 282. WILLIS, T.A. : The Phylogeny of the Intervertebral Disc: a Pic t o r i a l Review. C l i n i c a l Orthopedics and Re-lated Research. 54: 215-233, 1967. 283. WILSON, J.C. : Low Back Pain and Sciatica: a Plea for Better Care of the Patient. JAMA. 200: 705-712, 1967. 284. WILSON, P.D. : Low Back Pain, a Problem for Industry. Archives of Environmental Health. 4: 505-510, 1962. 285. WILTBERGER,. B.R.: Surgical Treatment of Degenerative Disease of the Back. J. Bone Joint Surg. 45A: 1509-1516, 1963. : Spondylolisthesis in Children. C l i n i c a l Ortho-pedics and Related Research. 21: 156-163, 1961. : Spondylolisthesis: Classification and Etiology. American Academy of Orthopedic Surgeons Symposium on the Spine. St. Louis. The C.V. Mosby Company. 1969. : The Effect of the Common Anomalies of the Lumbar Spine upon Disc Degeneration and Low Back Pain. Orthopedic Clinics of North America. 2: 569-582, 1971. 289. WILTSE, L.L., and HUTCHINSON, R.H.: Surgical Treatment of Spondylo-listhesis. C l i n i c a l Orthopedics and Related Re-search. 35: 116-135, 1964. 290. WING, P.C, and KOKAN, P.J.: A Proposal for a Prospective Etiolog-i c a l Investigation of Low Back Pain in an In-dustrial Setting. Vancouver. Orthopedic and Trauma Research Unit, University of British Columbia. 1972. 286. WILTSE, L.L. 287. WILTSE, L.L. 288. WILTSE, L.L. 217. 291. WOLFE, H.J., PUTSCHAR, W.G.J., and VICKERY, A.L.: Role of the Notochord i n the Human Intervertebral Disc. C l i n i c a l Orthopedics and Related Research. 39: 205-212, 1965. 292. YAMAJI, K., and MISU, A.: Kinesiologic Study with Electromyography of Low Back Pain. Electromyography. 8: 187, 1968. 293. ZBOROWSKI, M. : People in Pain. San Fransisco. Jossey-Bass. 1969. 2 1 8 . APPENDIX 1. This appendix shows the orthopedic data collection forms i n the style used during the study. The figures at the l e f t margin indicate the anticipated column or columns the data would occupy on the punched cards i n i t i a l l y used as input for the computer pro-cessing. The name in block letters i s that used in data analysis and as shown in certain of the tables described in the text (these were required as the name on the computer printout must usually be limited to eight characters). An asterisk against this name indi-cates when recombination of the groups was required for a partic-ular variable to f a c i l i t a t e i t s s t a t i s t i c a l manipulation by making i t more quantitative: for example, the variable recording smoking habit was rearranged by such recombination to reflect the degree of the smoking by the individual. A second code name in parentheses indicates the name assigned to a recombined variable i f the recom-bination was not done at the beginning of the analysis. Not a l l variables were used for purposes of correlation in the light of i n i t i a l responses to each of them. 219. Low Back P a i n - P a t i e n t S e l f e v a l u a t i o n . ' P a t i e n t code number I n s t r u c t i o n s : I n a l l c a s e s , p l a c e a r i n g round t h e number o p p o s i t e the one answer t h a t seems most a p p r o p r i a t e t o you. The column on the l e f t r e f e r s t o t h e way you were a p p r o x i m a t e l y one month b e f o r e y our f u s i o n o p e r a t i o n , t h e column on t h e r i g h t t o the way'you are now. I f you have d i f f i c u l t y , p l e a s e ask f o r h e l p . T r y and answer a l l t h e d i f f e r e n t p a r t s . Nature o f P a i n One month b e f o r e f u s i o n 9-10 0 1 2 SEVERITY 3 4 5 6 11-12 LOWBACK* 13-14 INTESCAP 15-16 NECK(S) 0 1 2 3 4 0 1 2 3 0 1 2 3 Now 0 1 2 3 4 5 6 0 1 2 3 4 0 1 2 3 0 1 2 3 S e v e r i t y o f p a i n No p a i n M i l d p a i n , n o t a problem P a i n a n n o y i n g , b u t f o r g o t t e n d u r i n g a c t i v i t y P a i n p r e s e n t even d u r i n g a c t i v i t i e s Moderate p a i n , i n t e r f e r e s w i t h a c t i v i t i e s o r s l e e p P a i n p r e v e n t s a c t i v i t y o r s l e e p Severe p a i n , i s i m m o b i l i s i n g L o c a t i o n - low back Ho p a i n i n low back Low back, i n the c e n t r e Low back, on the l e f t m o s t l y Low back, on t h e r i g h t m o s t l y Low back g e n e r a l l y P a i n between s h o u l d e r b l a d e s - do you have i t ? No O c c a s i o n a l l y O f t e n Most o f t h e t i m e F a i n i n t h e neck - do you have i t ? No O c c a s i o n a l l y O f t e n Most o f the time / 220. 17-18 BUTTOCK* One month before fusion 0 1 2 3 4 5 6 7 8 9 19-20 COCCYX* 21-22 HEADACHE 23-24 LEGS* 25-26 VALSALVA* 27-28 SITTING* 0 1 2 3 0 1 2 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 0 1 2 3 4 Now 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 0 1 2 3 4 5 6 7 8 9 Location of pain in buttocks or thighs No pain in these places Left buttock Right buttock Both buttocks Left thigh Right thigh Both thighs Left buttock and thigh Right buttock and thigh Both buttocks and thighs Do you feel pain in the tip of your tailbone? No Occasionally Often Most of the time Do you get, migraine or headaches? Seldom or never Occasionally Frequently Location of pain in leg's and feet. No pain hero Left calf Right calf Both calves Left calf and foot Right calf and foot Both calves and feet Left heel and/or foot Right heel and/or foot Both heels and/or feet Factors Affecting The Pain Coughing, sneezing or straining at stool 0 No particular effect on pain 1 Improves or lessens pain 2 Makes pain worse 3 Have not tried i t 4 Cannot te l l Sitting in an upright or firm chair 0 No particular effect on pain 1 Improves or lessens pain 2 Makes pain worse 3 Have not tried it 4 Cannot tell 221 . 29-30 RECLINE* One month b e f o r e f u s i o n Now 0 0 1 1 2 2 3 3 4 4 31-32 LYING* 0 0 1 1. 2 2 3 3 4 4 S i t t i n g i n a c o m f o r t a b l e o r r e c l i n i n g c h a i r No p a r t i c u l a r e f f e c t on p a i n Improves o r l e s s e n s p a i n Makes p a i n worse Have n o t t r i e d i t Cannot t e l l L y i n g f l a t No p a r t i c u l a r e f f e c t on p a i n Improves o r l e s s e n s p a i n Makes p a i n worse Have n o t t r i e d i t Cannot t e l l 33-34; WALKING* 35-36 BENDING* 37-38 LIFTING* 0 1 2 3 4 0 1 2 3 4 0 1 2 3 4 0 1 2 3 4 0 1 2 3 4 0 1 2 3 4 W a l k i n g No p a r t i c u l a r e f f e c t on p a i n Improves o r l e s s e n s p a i n Makes p a i n worse Have n o t t r i e d i t Cannot t e l l Bending f o r w a r d o r sideways No p a r t i c u l a r e f f e c t on p a i n Improves o r l e s s e n s p a i n Makes p a i n worse Have n o t t r i e d i t Cannot t e l l L i f t i n g No p a r t i c u l a r e f f e c t on p a i n Improves o r l e s s e n s p a i n Makes p a i n worse Have n o t t r i e d i t Cannot t e l l 39-40 CURLED* 0 1 2 3 4 L y i n g c u r l e d up 0 No p a r t i c u l a r e f f e c t on p a i n 1 Improves o r l e s s e n s p a i n 2 Makes p a i n worse 3 Have not t r i e d i t 4 Cannot t e l l 43-44 HEAT* 0 1 2 3 4 neat o r warm-on 0 No p a r t i c u l a r e f f e c t on p a i n 1 Improves o r l e s s e n s p a i n 2 Makes p a i n worse 3 Have n o t t r i e d i t 4 Cannot t e l l 222. 45-46 COLD* 47-48 MANIP* 49-50 ANALGES* 5.1-52 CORSET* 53-54 TIME* 55-56 STIFF* 0 1 2 3 4 0 1 2 3 4 0 1 2 3 4 57-58 WEAKNESS* One month Now b e f o r e f u s i o n C o l d 0 0 No p a r t i c u l a r e f f e c t on p a i n 1 1 Improves o r l e s s e n s p a i n 2 2 Makes p a i n worse . 3 3 Have not t r i e d i t 4 4 Cannot t e l l M a n i p u l a t i o n by c h i r o p r a c t o r o r f r i e n d 0 No p a r t i c u l a r e f f e c t on p a i n 1 Improves o r l e s s e n s p a i n 2 Makes p a i n worse 3 ' Have not t r i e d i t 4 Cannot t e l l S i mple p a i n p i l l s ( s u c h as a s p i r i n ) 0 No p a r t i c u l a r e f f e c t on p a i n 1 Improves o r l e s s e n s p a i n 2 Makes p a i n worse 3 Have n o t t r i e d i t 4 Cannot t e l l C o r s e t o r o r t h o p e d i c type b e l t 0 No p a r t i c u l a r e f f e c t on p a i n 1 Improves o r l e s s e n s p a i n 2 Makes p a i n worse 3 Have not t r i e d i t 4 Cannot t e l l The time o f day t h e p a i n i s w o r s t 0 No p a i n 1 The p a i n has no r e l a t i o n t o the time o f day 2 Morning 3 M i d d l e o f day 4 E v e n i n g 5 E v e n i n g and n i g h t 6 Morning and evening 7 N i g h t 8 A l l day 9 Day and n i g h t S t i f f n e s s No s t i f f n e s s o r v e r y l i t t l e S t i f f n e s s m o s t l y i n t h e back S t i f f n e s s m o s t l y i n t h e l e f t l e g S t i f f n e s s m o s t l y i n t h e r i g h t l e g S t i f f n e s s m o s t l y i n both l e g s S t i f f n e s s i n t h e back and l e f t l e g S t i f f n e s s i n t h e back and r i g h t l e g S t i f f n e s s i n t h e back and both l e g s Weakness i n t h e l e g s No l e g weakness Weakness i n . both l e g s Weakness i n l e f t l e g Weakness i n r i g h t l e g 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 0 1 2 3 0 1 2 3 4 5 6 7 0 1 2 3 223. 59-60 SENSAT* One month b e f o r o f u s i o n 0 1 2 3 4 61-62 CHORES* ( i n v e r t e d ) 63-64 MOBILE 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 Now 0 1 2 3 4 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 Changes i n f e e l i n g i n l e g s No changes Change i n f e e l i n g i n r i g h t l e g Change i n f e e l i n g i n l e f t l e g Change i n f e e l i n g i n b o t h l e g s Change i n f e e l i n g i n o t h e r p a r t s A b i l i t y t o manage D a i l y L i f e Household c h o r e s . Mark t h e one t h a t i n d i c a t e s t h e most d i f f i c u l t o f t h o s e l i s t e d t h a t you manage. Cannot manage a n y t h i n g Washing up Cooking C l e a n i n g k i t c h e n C l e a n i n g and t i d y i n g house Making beds Washing o r p o l i s h i n g f l o o r s C a r r y i n g a heavy o b j e c t such as a s u i t c a s e Moving heavy f u r n i t u r e Doing heavy d i g g i n g i n t h e garden o r s i m i l a r W a l k i n g . No l i m i t t o w a l k i n g I have t o st o p a f t e r about a h a l f m i l e because o f d i s c o m f o r t I can o n l y walfe 2-3 b l o c k s b e f o r e I must r e s t I can o n l y walk v e r y s h o r t d i s t a n c e s , b u t can manage s t a i r s and get around t h e house. I cannot manage s t a i r s I need h e l p t o move even i n the house I have t o use a w h e e l c h a i r 65-66 IHDEPEND* 0 1 2 3 ( i n v e r t e d ) 4 67-68 CHAIR* 69-70 FLOOR* 0 1 3 4 0 1 2 3 4 0 1 2 3 0 1 3 4 0 1 2 3 4 C a r i n g f o r y o u r s e l f - mark the most you can do. Unable t o l o o k a f t e r m y s e l f I can f e e d and wash m y s e l f but need h e l p d r e s s i n g I am a b l e t o do t h e above; I can c u t my own t o e n a i l s I can d r e s s m y s e l f c o m p l e t e l y but need h e l p w i t h some t h i n g s . I am t o t a l l y independent S i t t i n g , g e t t i n g up N e i t h e r o f these g i v e s me any d i s c o m f o r t I can s i t down but g e t t i n g up from t h e s i t t i n g p o s i t i o n may h u r t . G e t t i n g up does n o t h u r t but a c t u a l l y s i t t i n g may h u r t Both s i t t i n g down and g e t t i n g up may h u r t Because o f d i f f i c u l t y I need h e l p wit-h s i t t i n g down and r i s i n g from a c h a i r P i c k i n g t h i n g s up o f f the f l o o r I can p i c k t h i n g s up o f f the f l o o r w i t h o u t d i f f i c u l t y Bending h u r t s , but I can s t r a i g h t e n up w i t h o u t d i f f i c u l t y I can g e t down t o p i c k something up but s t r a i g h t e n i n g h u r t s Both bending and s t r a i g h t e n i n g up h u r t Because o f d i s c o m f o r t I j u s t can't p i c k t h i n g s up o f f the f l o o r One month Now b e f o r e f u s i o n 71-72 0 1 2 MARITAL* 3 4 5 6 7 73-74 0 1 2 BLISS 3 4 75-76 0 0 SEX* i i 2 2 3 3 4 4 77-78 0 0 1 1 2 2 SOCIAL* 3 3 4 4 79-80 o 0 1 1 2 2 MONEY 3 -j 81-82 o 0 1 1 WORK* 2 2 3 3 4 4 5 5 6 6 0 1 2 3 4 5 6 7 0 1 2 3 4 224. M a r i t a l s t a t u s S i n g l e M a r r i e d (one ma r r i a g e o n l y ) M a r r i e d ( l have been m a r r i e d more t h a n once) Se p a r a t e d D i v o r c e d Widowed Engaged t o be m a r r i e d 'Common-law' ( l i v i n g t o g e t h e r , n o t m a r r i e d ) M a r i t a l r e l a t i o n s h i p ( i n c l u d e s common-law p a r t n e r s h i p s ) S i n g l e a t p r e s e n t Happy and f a i r l y secure i n my p r e s e n t r e l a t i o n s h i p F a i r l y happy, but q u i t e obvious ups and downs Our r e l a t i o n s h i p i s n o t v e r y good We a r e l i k e l y t o s p l i t up soon S e x u a l l i f e - g e n e r a l - Mark the one t h a t most a p p l i e s t o you Normal - no problem a t a l l Back p a i n n e c e s s i t a t e s the use o f c e r t a i n p o s i t i o n s Frequency i s g r e a t l y l i m i t e d by back p a i n B o t h o f t h e above a r e t r u e (1 and 2) I n t e r c o u r s e i s not p o s s i b l e because o f some o t h e r i l l n e s s o r d i f f i c u l t y i n e i t h e r p a r t n e r S o c i a l a c t i v i t i e s - g o i n g out w i t h f r i e n d s ; t o p a r t i e s o r dances e t c . No l i m i t a t i o n f o r any reason No change i n t h e t y p e o f a c t i v i t i e s , but l e s s o f t e n because o f p a i n I have had t o change t o e a s i e r a c t i v i t i e s because o f back p a i n I can do v e r y l i t t l e ' because o f p a i n I have had t o change a c t i v i t i e s f o r some o t h e r r e a s o n F i n a n c i a l I am c o m f o r t a b l y o f f f i n a n c i a l l y I have no d e b t s , b ut would l i k e t o have more money i n r e s e r v e . I have some s m a l l d e b t s I am i n a f a i r l y s e r i o u s f i n a n c i a l p o s i t i o n Work I am n o t w o r k i n g , but t h i s i s n o t because o f i l l n e s s I do n o t work because o f i l l n e s s , but n o t because o f back t r o u b l e . I am a b l e t o c o n t i n u e my u s u a l work w i t h o u t d i f f i c u l t y . I f i n d my work q u i t e d i f f i c u l t and u n c o m f o r t a b l e because o f my back t r o u b l e I can o n l y work p a r t time because o f my back t r o u b l e I have had t o change t o an e a s i e r j o b because o f t h i s back t r o u b l e . I have had t o change t o an e a s i e r j o b f o r some o t h e r r e a s o n . 225. One month b e f o r e f u s i o n Now 83-84 Car d r i v i n g - mark the answer most a p p r o p r i a t e t o you 0 0 I do n o t d r i v e (have n o t l e a r n e d t o ) 1 I I cannot a t the moment d r i v e , but t h i s i s not CAR* connected w i t h my back 2 2 1 have no d i f f i c u l t y d r i v i n g a c a r 3 3 A l o n g c a r j o u r n e y causes unreasonable d i s c o m f o r t , but s h o r t e r t r i p s a r e not p a r t i c u l a r l y u n c o m f o r t a b l e 4 4 1 cannot t a k e l o n g c a r j o u r n e y s , and s h o u l d s t o p every |-1 hour f o r a r e s t , even s h o r t e r t r i p s a r e u n p l e a s a n t . 5 5 1 can o n l y d r i v e l o c a l l y because o f d i s c o m f o r t 6 6 I cannot d r i v e a t a l l because o f d i s c o m f o r t 85-86 R i d i n g i n a c a r o r bus 0 0 1 have no d i f f i c u l t y 1 I I have d i f f i c u l t y g e t t i n g i n o r r i d i n g but n o t due TRANSPOR* t o my back t r o u b l e 2 2 1 f i n d i t h a r d t o g e t i n o r out o f a c a r o r bus, but r i d i n g i s f a i r l y c o m f o r t a b l e 3 3 1 f i n d g e t t i n g i n and out f a i r l y easy, but t r a v e l l i n g i s u n c o m f o r t a b l e 4 4 1 f i n d b o t h g e t t i n g i n and out d i f f i c u l t and r i d i n g u n comfortable 5 5 . 1 a v o i d t r a v e l l i n g i n a c a r o r bus whenever p o s s i b l e because o f d i f f i c u l t y 87-88 CHILDREN* 0 1 2 3 4 C h i l d r e n o r g r a n d c h i l d r e n a t home - mark t h a t most a p p r o p r i a t e 0 No c h i l d r e n under f i f t e e n a t home 1 I am a b l e t o work and p l a y w i t h them and t o h e l p care f o r them 2 I have t o be c a r e f u l t h e y ' r e not t o o rough; I cannot l i f t them 3 I can do l i t t l e w i t h them - o n l y t a l k o r r e a d o r p l a y v e r y easy games 4 I cannot share a c t i v i t i e s w i t h them a t a l l . 89-90 SLEEP* 0 1 2 3 4 5 6 S l e e p 0 I s l e e p n o r m a l l y most n i g h t s 1 I o f t e n have d i f f i c u l t y i n g e t t i n g t o s l e e p because o f d i s c o m f o r t 2 I o f t e n have d i f f i c u l t y i n g e t t i n g t o s l e e p but don't know why 3 I wake up e a r l y because o f d i s c o m f o r t and cannot g e t enough s l e e p 4 I wake up e a r l y and cannot g e t enough s l e e p but don't know why 5 Another i l l n e s s o f mine i n t e r f e r e s w i t h my s l e e p 6 I cannot s l e e p because o f i l l n e s s o r upset o f a n o t h e r person i n t h e f a m i l y 226. One month Now b e f o r e f u s i o n 91-92 o o 1 1 L I F E * 2 2 3 3 4 4 5 5 93-94 0 1 ABDOMEN* 2 3 4 5 -6 7 8 9 •95-96 0 1 DYSPEP 2 3 4 '5 6 7 8 9 97-93 1 2 SKIN* o In G e n e r a l I e n j o y l i f e I e n j o y l i f e , but q u i t e a b i t l e s s than I d i d b e f o r e t h i s back t r o u b l e arose T h i s back problem i s enough t o s p o i l t h i n g s f o r me most o f the time L i f e i s o n l y j u s t t o l e r a b l e because o f t h i s back ( o r l e g ) d i s c o m f o r t I have even thought o f s u i c i d e because o f t h i s problem My enjoyment o f l i f e i s more a f f e c t e d fay o t h e r problems Some o t h e r q u e s t i o n s Any major abdominal s u r g e r y None Surger y f o r u l c e r i n stomach o r duodenum G a l l b l a d d e r o p e r a t i o n Kidney o r b l a d d e r o r male organs Female organs Because o f i n j u r y Bowel s u r g e r y Two o f t h e above Three o f t h e above Four o f the above Stomach t r o u b l e (mark o n l y one) No t r o u b l e O c c a s i o n a l i n d i g e s t i o n o r h e a r t b u r n - no m e d i c a t i o n . needed F a i r l y f r e q u e n t i n d i g e s t i o n o r h e a r t b u r n - I t a k e stomach m e d i c i n e s . Q u i t e bad i n d i g e s t i o n o r h e a r t b u r n - I've had t o have treatment from a d o c t o r D i a g n o s i s o f u l c e r made by the d o c t o r , and tr e a t m e n t g i v e n I've had treatment i n h o s p i t a l f o r an u l c e r once (but n o t s u r g e r y ) I've had tre a t m e n t i n h o s p i t a l more t h a n once (but n o t s u r g e r y ) I've had a b l e e d i n g u l c e r I've had a p e r f o r a t e d u l c e r I've had s u r g e r y f o r my u l c e r S k i n d i s e a s e s Seldom o r never P s o r i a s i s Frequent r a s h e s o r i t c h i n g now I've had problems w i t h my s k i n s i n c e c h i l d h o o d . 227. FSTIi.lATICW OF RESULTS RESULT Rate- on the line below with a single stroke of VOUT pen the success of your last fusion operation. E x t r e m e l y p o o r . Extremely good Back S u r g e r y Form 228. \2 3-8 9-10 a-12 13-14 15 Dr. Kokan - Dr. V/ing Date, o f e x a m i n a t i o n H o s p i t a l P a t i e n t ' s c h a r t number .*. DVA, Pension o r WC3 number Age i n y e a r s a t examination Age i n y e a r s a t l a s t f u s i o n . Age. i n y e a r s a t onset o f symptons.... Time l a p s e o n s e t / f u s i o n i n months Sex 1 Male GENDER 2 F e m a l e AGE AFUSION ASYMPTOM LAPSE 16 P l a c e o f b i r t h BIRTHPL* 0 1 2 3 4 5 6 7 8 9 B.C. Canada o t h e r than B.C. U n i t e d Kingdom N o r t h e r n o r Western Europe S o u t h , C e n t r a l o r E a s t e r n Europe Middle. E a s t ( e g . I s r a e l , Lebanan, I n d i a ) F a r E a s t ( e g . C h i n e s e , Japanese) B r i t i s h Commonwealth America (U.S.) Other 17 C u l t u r a l background ( o f p a r e n t s , g r a n d p a r e n t s o r o f c h i l d h o o d s u r r o u n d i n g s ) ETHNIC 0 1 2 3 4 5 6 7 8 9 N o r t h American F r e n c h o r F r e n c h Canadian B r i t i s h (would i n c l u d e Commonwealth) M e d i t e r r a n e a n ( I t a l i a n , S p a n i s h e t c . i n c l u d e S.America) I n d i a n , P a k i s t a n i o r s i m i l a r C h i n e s e , Japanese o r s i m i l a r N o r t h e r n o r Western European C e n t r a l o r E a s t e r n European A f r i c a n Other 18. E d u c a t i o n EDUCAT 0 1 2 3 4 5 6 7 8 9 I l l i t e r a t e I ncomplete p r i m a r y Complete p r i m a r y Incomplete secondary Complete secondary Trade o r b u s i n e s s t r a i n i n g P r o f e s s i o n a l t r a i n i n g not i n c l u d e d i n 5 U n i v e r s i t y - b a c h e l o r ' s degree o r s i m i l a r U n i v e r s i t y - f u r t h e r t r a i n i n g beyond b a c h e l o r ' s degree Other 229. O c c u p a t i o n 19-20 P r o f e s s i o n a l o r e q u i v a l e n t Time of fusion 0 OCCUPA 1 2 3 4 5 6 7 8 9 Now 0 1 2 3 4 . 5 6 7 8 9 Not i n t h i s category-M e d i c a l , d e n t a l , v e t e r i n a r y , o s t e o p a t h i c L e g a l ( i n c l u d e j u r i s t s ) A r c h i t e c t E n g i n e e r i n g ( a t c o n s u l t a n t o r d e s i g n l e v e l ) T e a c h i n g Government ( s e n i o r p o s i t i o n , department head e t c . ) M a j o r e x e c u t i v e i n commerce High rank i n m i l i t a r y f i e l d , p o l i c e o r t r a n s p o r t f i e l d s O t h e r p r o f e s s i o n a l o r e q u i v a l e n t 21-22 T e c h n i c a l , s k i l l e d , c l e r i c a l OCCUPB 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 Not i n t h i s c a t e g o r y P a r a m e d i c a l - n u r s e s , t e c h n i c i a n s , B a n k i n g (management o r s u p e r v i s i n g ) C r e a t i v e w r i t e r s ( a u t h o r s , j o u r n a l i s t s e t c ) and p e r f o r m i n g a r t i s t s ' . P h o t o g r a p h e r s , a r t i s t s , s c u l p t o r s , commercial a r t i s t s . Salesmen ( e x c l u d i n g m a j o r e x e c u t i v e s and s a l e s c l e r k s ) C l e r i c a l S k i l l e d w o r k e r s , s e r v i c i n g ( e . g . e l e c t r i c i a n , p l u m b e r ) A g r i c u l t u r a l ( f a r m e r s , f o r e s t r y , f i s h i n g , . h u n t i n g ) P o l i c e & m i l i t a r y p e r s o n n e l except h i g h e s t r a n k s 23-24 O t h e r s 0 OCCUPC 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 Not i n t h i s c a t e g o r y S a l e s c l e r k s P r o d u c t i o n w o r k e r s (manufacture o r assembly) T r a n s p o r t o r v e h i c l e o p e r a t o r s and a n c i l l a r y p e r s o n n e l C o n s t r u c t i o n w o r k e r s C a t e r i n g and a n c i l l a r y p e r s o n n e l Housewife U n s k i l l e d l a b o u r S t u d e n t O t h e r n o t c a t e g o r i s e d - p l e a s e s p e c i f y . •25—26 O c c u p a t i o n changes most r e c e n t l y B e f o r e f u s i o n A f t e r f u s i o n 0 CHANGOC 0 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 None (no change) Promotion i n a s i m i l a r j o b Change, t o a d i f f e r e n t j o b , as advancement Change t o a d i f f e r e n t j o b f o r reasons o t h e r t h a n i l l n e s s Change t o a d i f f e r e n t j o b because o f back d i s a b i l i t y Change t o a d i f f e r e n t j o b because o f o t h e r i l l n e s s C e s s a t i o n o f employment f o r age r e t i r e m e n t C e s s a t i o n o f employment because o f back d i s a b i l i t y C e s s a t i o n o f employment because o f o t h e r r e a s o n s . 230. -28' . Number o f j o b changes 29. Time l o s s i n l a s t 2 y e a r s B e f o r e f u s i o n A f t e r f u s i o n 0 - None 0 0 None. 1 L e s s than 1 week JOBNO 1 1 1 2 L e s s than 1 month 2 2 2 3 L e s s than 2 months 3 3 3 4 Less than 4 months 4 4 4 5 Less than 6 months 5 5 5 6 L e s s than 1 y e a r 6 6 6 7 Less than 18 months 7 7 7 8 L e s s than 2 y e a r s 8 8 8 9 Unemployed 9 9 More t h a n 8 LOSS 30 Time o f f work p r i o r t o l a s t f u s i o n ( o r o p e r a t i o n i f no f u s i o n ) 0 N> o p e r a t i o n PRIOR 1 L e s s t h a n 1 month 2 L e s s t h a n 2 months 3 L e s s t h a n 4 months 4 L e s s t h a n 6 months 5 L e s s t h a n 1 y e a r 6 L e s s t h a n 2 y e a r s 7 L e s s t h a n 4 y e a r s 8 L e s s t h a n 10 y e a r s 9 More t h a n 10 y e a r s 31. Time o f r e t u r n t o work a f t e r l a s t  F u s i o n ( o r o p e r a t i o n i f no f u s i o n ) RETURN 0 No o p e r a t i o n 1 Less than 1 month 2 L e s s than 2 months 3 L e s s than 4 months 4 L e s s than 6 months 5 L e s s than 1 y e a r 6 L e s s than 2 years. 7 L e s s than 4 y e a r s 8 L e s s than 10 y e a r s 9 More than 10 y e a r s 32 R e l i g i o n 0 FAITH* 1 2 3 4 5 6 7 8 9 No d e f i n i t e v i e w s A t h e i s t J e w i s h Roman C a t h o l i c B u d d h i s t Hindu Mohammedan Ot h e r O r i e n t a l S p e c i f i c p r o t e s t a n t s e a t o r denomination O t h e r ' p r o t e s t a n t ' ( i n c l u d e here Church o f England e t c . ) -33 A c t i v i t y i n r e l i g i o u s l i f e 0 Never „ 1 Once-twice y e a r l y A C T I Y E 2 ' O c c a s i o n a l ' 3 R e g u l a r a t t e n d e r a t a p l a c e of r e l i g i o n ( t w i c e monthly or more) 4 'Deeply r e l i g i o u s ' 5 A c t i v e i n o r g a n i s a t i o n o f p a r t i c u l a r c h u r c h 6 M i n i s t e r of p a r t i c u l a r c h u r c h 7 C o n s i d e r e d a r e l i g i o u s p e r s o n , b ut does n o t t a k e p a r t i n an o r g a n i s e d church 231. 34-35 A v o c a t i o n One month b e f o r e f u s i o n Now 0 0 1 1 2 2 3 3 4 4 5 5 6 6 HOBBY* None ' A t h l e t i c s , c o m p e t i t i v e A t h l e t i c s , non c o m p e t i t i v e M a j o r s p o r t s ( r u n n i n g , s k i i n g , c y c l i n g , swimming) M i n o r s p o r t s ( w a l k i n g , j o g g i n g , h u n t i n g , g o l f , f i s h i n g ) C r e a t i v e ( i n d o o r , l i g h t e r work) Domestic maintenance, g a r d e n i n g , house c a r e , e t c . F a m i l y H i s t o r y 36 Number o f s i b l i n g s o f f a t h e r UNCLE 37. F a t h e r and s i b l i n g s o f f a t h e r w i t h back troub.V 38 AUNT SIBS 40-41 0 None 0 None 1 1 EXUNCLE 1 F a t h e r 2 2 2 1 s i b l i n g o f f a t h e r 3 3 3 2 s i b l i n g s o f f a t h e r 4 4 4 3 s i b l i n g s o f f a t h e r 5 5 5 4 s i b l i n g s o f f a t h e r 6 6 6 1 * 2 7 7 7 1 * 3 8 8 8 1 + 4 9 More t h a n 8 9 . 1 + 5 Number o f s i b l i n g s o f mother 39. •Mother and s i b l i n g s o f mother 0 None 0 None 1 1 1 Mother 2 2 EX AUNT 2 1 s i b l i n g o f mother 3 3 3 2 s i b l i n g s o f mother 4 4 4 3 s i b l i n g s o f mother 5 5 5 4 s i b l i n g s , o f mother 6 6 6 1 + 2 7 7 7 • 1+ 3 8 8 8 1 + 4 9 More than 8 9 1 + * Number o f p a t i e n t ' s s i b l i n g s Number o f c h i l d r e n A t t i m e o f f u s i o n OFF(F)(N) 0 1 2 3 • 4 . 5 6 7 8 9 Nov; 0 1 2 3 4 5 6 7 8 None 1 2 3 4 5 6 7 8 More t h a n 8 Number w i t h back t r o u b l e . . . . SIBBACK 42. Number o f c h i l d r e n w i t h back t r o u b l e  OR PAIN (now) 0 None 1 1 2 2 OFFBACK 3 3 4 4 5 5 6 6 7 7 8 8 9 More than 8 232. 43. Nu-ubcr o f c h i l d r e n w i t h l e g p a i n , «rheu,matism& o r 'growing p a i n s ' i (now) QFFRHEU 0 None 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 More than 8 44 Smoking h a b i t SMOKE* 0 Non smoker 1 M a i n l y c i g a r e t t e s 2 M a i n l y c i g a r e t t e s 3 M a i n l y c i g a r e t t e s 4 M a i n l y c i g a r e t t e s 5 M a i n l y p i p e 6 M a i n l y p i p e 7 M a i n l y c i g a r 8 M a i n l y c i g a r 9 Combination • l e s s t h a n 10 d a i l y l e s s t h a n 20 d a i l y l e s s t h a n 40 d a i l y more t h a n 40 d a i l y - moderate smoker - heavy smoker - moderate smoker - heavy smoker f a i r l y heavy 45 BOOZE* A l c o h o l usage 0 1 2 3 4 6 7 8 9 T e e t o t a l l e r ( a b s t a i n e r ) O c c a s i o n a l d r i n k - s p e c i a l o c c a s i o n s o n l y O c c a s i o n a l d r i n k a t home o r s o c i a l o c c a s i o n s D r i n k s once o r t w i c e most weeks, i n moder a t i o n D r i n k s e v e r y week a t l e a s t once a s a major p a r t o f t h e e v e n i n g ' s e n t e r t a i n m e n t Has an a l c o h o l d r i n k o f some s o r t d a i l y , may o r may n o t d r i n k more a t t i m e s P r o b a b l y r e l i e s on a l c o h o l beyond normal s o c i a l use E a r l y a l c o h o l i c U n e q u i v o c a l l y a l c o h o l i c E x - a l c o h o l i c , o r member o f AA 46 Drug use 0 DRUG* 1 2 3 4 5 6 7 8 9 mark h i g h e s t grade None O c c a s i o n a l s o f t drug u s e r F r e quent o r h a b i t u a l s o f t d r u g u s e r Has had a c o n v i c t i o n r e l a t e d t o s o f t d r u gs O c c a s i o n a l non-medical u s e r o f s t i m u l a n t s o r t r a n q u i l l i s e r s F r e q u ent non-medical u s e r o f s t i m u l a n t s o r t r a n q u i l l i s e r s O c c a s i o n a l o p i a t e o r s i m i l a r u s e r A d d i c t t o o p i a t e o r s i m i l a r drug E x - a d d i c t o f o p i a t e o r d i m i l a r d rug Other - s p e c i f y 233. 47 O t h e r d i s e a s e s t a t e s ( r e q u i r i n g major i n o r o u t p a t i e n t t r e a t m e n t ) 0 None 1 C.N.S. ( e x c l u d i n g p s y c h i a t r i c c a r e ) DISEASE* 2- R e s p i r a t o r y 3 C a r d i o v a s c u l a r 4 G a s t r o i n t e s t i n a l e x c l u d i n g p e p t i c u l c e r d i s e a s e 5 G e n i t o u r i n a r y . 6 M u s c u l o s k e l e t a l 7 . Two o f above 8 Three o f above 9 F o u r o f above 48 P s y c h i a t r i c c a r e o r p e r s o n a l i t y d i s o r d e r 0 Normal 1 Moderate o r f r e a u e n t t r a n q u i l l i s e r u s e i.",\Y."~ 2 Had p s y c h i a t r i c a t t e n t i o n p r i o r t o f u s i o n 3 Has had p s y c h i a t r i c a t t e n t i o n s i n c e f u s i o n 4 1 + 2 5 1 + 3 6 2 + 3 7 1+2+3 8 C u r r e n t l y i n p s y c h i a t r i c ward 9 Other 49 H i s t o r y o f trauma r e l a t e d t o onset o f back t r o u b l e 0 None 1 M i n o r ( l i f t i n g , a t w i s t ) 2 F a l l from a low h e i g h t 3 F a l l from a g r e a t e r h e i g h t 4 M a j o r i n j u r y - f r a c t u r e 5 Repeated s t r e s s o r minor trauma 6 War i n j u r y o r s i m i l a r ( b l a s t , G.S.W. e t c ) 7 Auto a c c i d e n t RTRAUMA* 50 H i s t o r y o f o t h e r trauma p r i o r t o o n s e t o f symptoms but u n r e l a t e d 0 None OTRAUMA* 1 Lower l i m b f r a c t u r e i n s p o r t s o r s i m i l a r a c c i d e n t 2 Auto a c c i d e n t w i t h o u t f r a c t u r e o r maj o r i n j u r y 3 Auto a c c i d e n t w i t h f r a c t u r e o r major i n j u r y " 4 B a s t , GSW, o r s i m i l a r 5 F a l l from a low h e i g h t 6 Major f a l l 7 Two o f above •8 Three o f above 51 R e s i d u a l d i s a b i l i t y from o t h e r trauma (50) 0 No r e s i d u a l DISABIL 1 M i l d r e s i d u a l d i s c o m f o r t o r d i s a b i l i t y 2 Moderate r e s i d u a l d i s c o m f o r t o r d i s a b i l i t y - unperisioned 3 Severe r e s i d u a l d i s c o m f o r t o r d i s a b i l i t y - unpensioned 4 Moderate r e s i d u a l d i s c o m f o r t o r d i s a b i l i t y - pensioned 5 Severe r e s i d u a l d i s c o m f o r t o r d i s a b i l i t y - pensioned 234. 52 T o t a l number o f h o s p i t a l a d m i s s i o n s f o r back 53. T o t a l number o f o p e r a t i o n s on back ADMISS 0 1 2 3 4 5 6 7 8 9 None 1 o #» 3 4 5 6 7 8 More t h a n 8 0 1 2 3 4 5 6 7 8 9 None 1 2 3 4 5 6 7 8 More than 8 OPERATE 54 T o t a l number o f f u s i o n o p e r a t i o n s FUSIONO 55. T o t a l number o f l a m i n e c t o m i e s 0 None 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 More t h a n 8 0 1 2 3 4 5 6 7 8 9 None 1 2 3 4 5 6 7 8 More than 8 LAMINECT 56 --Nuraber-ef . r e f u s i o n s o f any l e v e l REFUSION 0 1 2 3 4 5 6 7 8 9 None 1 2 3 4 5 6 7 8 More than 8 57 C o m p l i c a t i o n s o f any and a l l back o p e r a t i o n s 0 1 2 3 4 5 6 7 8 9 None Wound i n f e c t i o n (deep) COMPLICA* Wound i n f e c t i o n ( s u p e r f i c i a l ) Hematoma Root damage o r i r r i t a t i o n P s e u d a r t h r o s i s Shock Chest o r abdominal problems More t h a n 1 of t h e above ( s p e c i f y ) Other 58 C o m p l i c a t i o n s o f l a s t f u s i o n o p e r a t i o n COMPLICB* 0 None 1 Wound i n f e c t i o n (deep) 2 Wound i n f e c t i o n ( s u p e r f i c i a l ) 3 Hematoma 4 Root damage, o r i r r i t a t i o n 5 P s e u d a r t h r o s i s 6 Shock 7, Chest o r abdominal problems 8 More than 1 o f t h e above ( s p e c i f y ) 9 Other 235. 59 G e n e r a l appearance - most predominant f e a t u r e 0 Normal, h e a l t h y 1 V e r y m u s c u l a r , n o t overweight GENERAL* 2 Overweight f o r h e i g h t 3 Appears v e r y t h i n 4 P a l e , u n h e a l t h y l o o k i n g 9 O t h e r 60 B l o o d P r e s s u r e 61. Weight i n k i l o s WEIGHT 0 Normal 1 Less than 40 (under 88 l b s ) 1 Low ( s y s t o l i c l e s s than 100 mm) 2 41-50 (89-110 l b s BP*. 2 H i g h ( d i a s t o l i c o v e r 90 mm) 3 51-60 (111-132 l b s ) 3 V e r y h i g h ( d i a s t o l i c o v e r 120 mm) 4 61-70 (133-154 l b s ) 5 71-80 . (155-176 l b s ) 6 81-90 (177-198 l b s ) 7 91-100 (199-220 l b s ) 8 101-110 (221-242 l b s ) 9 More than 110(more t h a n 293 l b s ) -2 H e i g h t i n c e n t i m e t r e s HEIGHT 1 l e s s than 120 2 121 - 130 3 131- 140 4 141- 150 5 151 - 160 6 161 - 170 7 171 - 180 8 181 - 190 9 More t h a n 190 (under 4' ) (4'0» - 4'3") (4'3^" - 4'7") (4'7|" - 4'11") (4'11|" - 5'3") (5'3i" - 5'7") (5'7l" - 5'11") .(-5-sii^--.6-«3*) (more than 6'3") FATFACT* = WEIGHT CODE HEIGHT CODE 63 ENT ENT* 64 Chest 0 normal 0 normal 1 abnormal ( s p e c i f y ) 1 abnormal ( s p e c i f y ) 2 n o t done 2 n o t done 65 Heart 0 normal 1 abnormal ( s p e c i f y ) 2 n o t done TUMMY* 0 1 2 3 4 5 6 7 8 9 CHEST* = 64+65 ( i . e . a b n o r m a l i t y o f e i t h e r ) . 66' Abdomen s c a r s any type Normal Obese 2 o r more H e r n i a of 1 + 2 1 + 3 2 + 3 1 + 2 + 3 O t h e r more s e r i o u s a b n o r m a l i t y r e q u i r i n g r e f e r r a l n o t done 236. 67 R e c t a l RECTAL* 0 1 2 3 4 5 6 7 8 9 Normal F i s s u r e and/or hemorrhoids C o c c y g e a l t e n d e r n e s s . A b n o r m a l i t y o f p r o s t a t e , s a c r o t u b e r o u a l i g a m e n t o r o t h e r deep s t r u c t u r e ( s p e c i f y ) 1 + 2 1 + 3 2 + 3 1 + 2 + 3 O t h e r more s e r i o u s a b n o r m a l i t y r e q u i r i n g r e f e r r a l Not done ( t h i s s h o u l d not be marked 1.) 69 Normal 1 L i m p i n g R . l e g 2 L i m p i n g L. l e g 3 D i f f i c u l t y i n b o t h l e g s 4 Unable t o walk £ Unable t o s t a n d i O t h e r - s p e c i f y GAIT* 70 S t a n c e STANCE* 71 P e l v i c T i l t 72 CURVE* 0 Normal 0 Normal' 1 L i s t t o r i g h t 1 R i g h t s i d e up TILT* 2 L i s t t o l e f t 2 L e f t s i d e up 3 L i s t f o r w a r d 4 L i s t backward 9 O t h e r ( s p e c i f y ) Lumbar c u r v e 73 P a r a v e r t e b r a l muscle tone 0 Normal l o r d o s i s 0 "Normal PVTONE*' 1 E x a g g e r a t e d l o r d o s i s .1 R i g h t p a r a v e r t e b r a l muscle spasm 2 F l a t t e n e d l o r d o s i s 2 " L e f t p a r a v e r t e b r a l muscle spasm 3 K y p h o s i s 3 1 + 2 4 S c o l i o s i s convex t o r i g h t 9 Other - s p e c i f y 5 S c o l i o s i s convex t o l e f t 6 1 + 4 7 1 + 5 8 2 + 4 9 2 + 5 74 Abdominal muscle tone 0 Normal ABDTONE* J J * ? 8 6 ' f a i r . * ? n e + 2 Not obese, but poor tone 3 Obese, poor tone 237. 75 C e r v i c a l s o i n e ranp,e o f motion 0 Normal f o r age CERVICA* i L i m i t e d f l e x i o n 2 L i m i t e d e x t e n s i o n 3 L i m i t e d t i l t and/or r o t a t i o n t o r i g h t 4 L i m i t e d t i l t and/or r o t a t i o n t o l e f t • 5 1 + 3 6 1 + 4 7 2 + 3 8 2 + 4 9 V i r t u a l l y o r c o m p l e t e l y a n k y l o s e d 76 C e r v i c a l s p i n e - o t h e r CERVICA and CERVICB 0 Normal combined as 'NECK(O) 1 r „ 1 P o s t e r i o r muscle abnormal tone 2 Tenderness on a x i a l compression ( o v e r v o r t e x ) 3 L o c a l i s e d t enderness o v e r c e r v i c a l s p i n e 4 1 + 2 , 5 1 + 3 6 2 + 3 7 1 + 2 + 3 9 Other ( s p e c i f y ) 77 Upper Limbs ( e i t h e r ) 0 Normal ARMS* 1 L i m i t a t i o n o f s h o u l d e r movement 2 C r e p i t u s i n s h o u l d e r r e g i o n on moti o n 3 N e u r o l o g i c a l impairment o f some type i n l i m b f ^ . r\ i|. J. T £. 5 - 1 + 3 6 2 + 3 7 1 + 2 + 3 9 Other ( s p e c i f y ) 78 T h o r a c i c s p i n e 79 Lumber spins'. ROM f l e x i o n Measure C7 t c 0 i f o r m a i - Sj. d i f f e r e n c e i n £5ls. THORACIC* 1 Abnormal curve ( s p e c i f y t y p e ) LUMFLEX 2 L i m i t e d r o t a t i o n 3 Marked tenderness ( s p e c i f y where) 4 1 + 2 5 1 + 3 6 2 + 3 7 1 + 2 + 3 9 Other - s p e c i f y 0 More th a n 8 cms 1 7-1 - 8 C313 2 6-1 - 7 cms 3 5-1 - 6 cms 4 4-1 - 5 cms 5 3-1 ' - 4 cms 6 2-1 - 3 cms 7 1-1 ~ 2 c m s 8 L e s s than 1 cm 80 F l e x i o n e x p r e s s e d d i f f e r e n t l y 0 Touch t o e s FLBXTWQ 1 B e l w mid t i b i a 2 M i d t i b i a • 3 Touches knees 4 M i d t h i g h 5 0° '81 Spasm on F l e x i o n ( o f p a r a v e r t e b r a l m u s c l e s ) SPASM 1 2 None Moderate Marked 238. 82 Lumbar r.nj.ro PCM ox to u n i o n 83 P a i n on e x t e n s i o n LDMEXT 84 RFLEX* 0 Normal 1 20 - 30° 2 10 - 20° 3 Lees t h a n 10° ROM R j ^ h t F l e x i o n O 1 2 3 Normal 30 - 45° - Knee j o i n t 15 - 30° - Lower t h i g h L e s s t h a n 15° - U i d t h i g h 0° RLFLEX .is. the .recombination, .of. RFLEJC+. LFLEX. 0 1 No Yea PAINEXT 85 ROM l e f t f l e x i o n 0 1 2 3 U Normal 30 - 45° 15 - 30° I.FLEX* Knee j o i n t Lov/er t h i g h L o s s t h a n 1 5 ° - M i d t h i g h 0° 87 HYPEREXT 89 PULSES* 91 KNEES* P a s s i v e .Hyperextension t e s t 88 0 F u l l p a s s i v e h y p e r e x t e n s i o n p a i n f r e o 1 G i v e s s l i g h t p a i n a t normal l i m i t 2 M i l d p a i n on h y p e r e x t e n s i o n ' 3 Moderate p a i n 4. Severe p a i n - r e l i e v e d by f l e x i o n 5 G i v e s p a i n n o t eased on f l e x i o n • Leg l e n g t h P e r i p h e r a l i o n i s e s •» lov.er l i m b s 0 Normal 1 M i l d decrease) r i g h t .2 . Marked decrease' r i g h t , 3 M i l d docreaso l e f t 4. Marked decrease l e f t 5 M i l d b i l a t e r a l decrease 6 More marked b i l a t e r a l decrease Knees 0 Normal 1 R i g h t abnormal ( s p e c i f y ) 2 L o f t abnormal ( s p e c i f y ) 3 I H " 2 ( s p e c i f y ) 90 1 2 3 4 5 6 H i p j O 1 2 3 E q u a l LENGTH* R i g h t s h o r t e r by 1-5 cms. -R i g h t s h o r t e r by 5-19 cms. R i g h t s h o r t e r by over 10 cms L o f t s h o r t s r by 1-5 cms. L e f t s h o r t e r by 5-19 cms. L e f t s h o r t e r by over 10 cms. I n d i c a t e cause. Normal R i g h t abnormal L e f t abnormal 1 4 2 , HIPS* ( s p e c i f y ) ( s p e c i f y ) ( s p e c i f y ) 92 A n k l e s 0 1 2 3 Normal ANKLES'* R i g h t abnormal ( s p e c i f y ) L e f t abnormal ( s p e c i f y ) 1 + 2 ( s p e c i f y ) LIMB i s ' the r e c o m b i n a t i o n o f HIPS + KNEES + ANKLES ' + RFOOT + LFOOT (normal l i m b versus abnormal), ( o v e r ) 239. 93 .*FOOT* R i g h t f o o t 0 Normal 1 A b n o n n a l i t y o f a r c h 2 H a l l u x v a l g u s 3 Claw o r hammer t o e s 4 1 + 2 5 1 + 3 6 2 + 3 7 1 + 2 + 3 9 O t h e r ( s p e c i f y ) 94 L o f t f o o t LFOOT* ± c a l l u s e s 0 Normal 1 A b n o r m a l i t y o f a r c h 2 H a l l u x v a l g u s 3 Claw o r hammer t o e s 1 c a l l u s e s 4 1 + 2 5 1 + 3 6 2 + 3 7 1 + 2 + 3 9 Other ( s p e c i f y ) 95 GAENSLEN* S a c r o i l i a c s t r c s 3 (Gaenslen's t e s t ) 0 Normal 1 R i g h t p o s i t i v e 2 L e f t P o s i t i v e 3 1 + 2 96 S t r a i g h t l e g r a i s i n g p a i n 0 N o n e ( n o r m a l ) SLR* 1 2 3 4 5 6 7 8 9 R i g h t R i g h t R i g h t L e f t L e f t L e f t B o t h l e g s B o t h l e g s B o t h l e g s . 0 - 3 0 degrees 30 - 60 6 0 - 9 0 0 - 3 0 30 - 60 60 - 90 0 - 3 0 30 - 60 60 - 90 97 B o w s t r i n g s i g n ( p r e s s u r e o v e r t a u t p o p l i t e a l n e r v e ) BOW* 0 N e g a t i v e b i l a t e r a l l y 1 P o s i t i v e l e f t .2 P o s i t i v e . i ' i g h i 3 b i l a t e r a l l y p o s i t i v e 98 Muscle w a s t i n g more than 2 0 None R i g h t t h i g h T.~ft t V""*> cms WASTA* 1 o j 4 5 6 7 8 9 L e f t c a l f 1 + 3 2 + 3 1 + 4 2 + 4 Other - s p e c i f y 99 Mu a c l e w a s t i n g-cont i n u e d 0 None i n t h i s group WASTB* i R i g h t e x t e n s o r d i g i t o r u m b r e v i s 2 L e f t » " " 3 R i g h t a n t e r i o r c a l f m u s c l e s 4 L e f t a n t e r i o r c a l f m u s c l e s 5 1 + 3 . 6 2 + 3 7 1 + 4 8 2 + 4 ' 9 Other - s p e c i f y WASTAB i s t o t a l number o f p o s i t i v e e n t r i e s i n WASTA and WASTB. 100 Abdominal - a b l e t o l i f t s t r a i g h t l e g s 10 era o f f t a b l e ? 0 Yes 1 No ABDPOWA 101 ABDPOWB A b i l i t y t o l i f e upper body o f f t a b i c - l e g 3 s e c u r e d 0 Normal - f a i r l y c a o i l y 1 W i t h d i f f i c u l t y - a l l t h e way 2 Moderate d i f f i c u l t y - o n l y p a r t way 3 Marked d i f f i c u l t y - o n l y j u s t a b l e t o move 4 Unable t o r i s e o f f t a b l e 240. 102 Back a b l e t o l i f t b u t t o c k s o f f t a b l o when su p i n o BACKPOW 0 Yes - n o r m a l l y and e a s i l y 1 W i t h some d i f f i c u l t y r e m a i n s extended 2 Moderate d i f f i c u l t y - ca n n o t s u s t a i n i t 3 Marked d i f f i c u l t y - u n a b l e t o r a i u e b u t t o c k s f r o a t a b l e 103 106 .10.9 112 Mn F l e x o r s 104 H i p e x t e n s or s 105 Hip a b d u c t o r s L R L R L R 0 0 Grade 5 0 0 Grade 5 0 • 0 Grade 5 1 1 Grade 4 - 1 1 Grade 4 1 1 Grade 4 2 2 Grade 3 2 2 Grado 3 2 2 Grade 3 3 3 Grade 2 3 3 Grade 2 3 3 Grade 2 4 Grade 1 4 4 Grade 1 4 4 ' Grade 1 5 5 No f u n c t i o n 5 5 Ho f u n c t i o n 5 . 5 No f u n c t i o n Hip A d d u c t o r s 107 Knee Ex t e n s o r s 108 Knee f l e x o r s L R L R L R 0 0 Grade 5 0 0 Grade 5 0 0 Grado 5 1 1 Grade 4 1 1 Grado 4 1 . 1 Grade- 4 2 2 Grade 3 2 2 Grade 3 2 2 Grade 3 J 3 Grado 2 3 3 Grade 2 3 3 Grade 2 4 Grade 1 4 4 Grado 1 4 4 Grade 1 5 5 Ho f u n c t i o n 5 5 Ho f u n c t i o n 5 5 Ho f u n c t i o n .Foot d c r s i 110 . F o o t f]. ant •nrflBTOTfl 111 F o o t E v e r t o r s JLI R L R L T> 1 . 0 0 Grade 5 0 0 Grado 5 0 0 Grade 5 1 ' 1 Grade 4 1 1 Grade 4 1 1 Grade 4 2 2 Grado 3 2 2 Grade 3 2 2 Grade 3 3 3 Grade 2 3 3 Grado 2 3 3 Grade 2 % Grade 1 4 4 Grade 1 4 4 Grade 1 5 5 K o ' f u n c t i o n 5 5 Ko f u n c t i o n 5 5 No f u n c t i o n G r e a t toe e x t e n s i o n 113 G r e a t t oe f l e x i o n L R L R 0 0 Grade 5 0 0 Grade 5 1 1 Grade 4 1 1 Grade 4 2 2 Grado 3 2 2 Grade 3 3 3 Grade 2 3 3 Grade 2 Grade 1 ft 4 Grade 1 5 5 Ho f u n c t i o n 5 5 Ko f u n c t i o n . LEGPOW i s t o t a l s c o r e o f a l l l i m b weakness measures. 114 Deep tendon r e f l e x - knee 115 Deep tendon r e f l e x - a' 0 Normal O Normal DTRKHES* 1 R i g h t i n c r e a s e d DTRANK* n . R i g h t i n c r e a s e d 2 R i g h t d ecreased 2 R i g h t d e c r e a s e d 3 R i g h t a b s ent 3 R i g h t a b s e n t 4 L e f t i n c r e a s e d 4 L o f t i n c r e a s e d 5 L e f t d e c r e a s e d 5 L e f t d e c r e a s e d 6 L e f t a b s e nt 6 L e f t a b s e n t 7 B o t h i n c r e a s e d 7 B o t h i n c r e a s e d 8 Both decreased 8 B o t h d e c r e a s e d 9 B o t h absent 9 B o t h a b s e n t 241 . 116 P l a n t a r r e f l e x 0 Normal PLANTAR* j_ R i r h t upgoing 2 L e f t upgoing 3' B o t h upgoing 117 Abdominal r e f l e x 0 Normal ABDFLEX* 1 Absent r i g h t 2 Absent l e f t 3 Absent b o t h s i d e s 4 Abnormal because o f l o c a l d i s e a s e 118 CREMAST* Cremaster r e f l e x 6 1 2 3 4 Normal Absent r i g h t Absent l e f t Absent both side.s Abnormal because o f l o c a l d i s e a s e 119 SENSR* S e n s a t i o n r i g h t - l e v e l o f impairment 0 None 1 L3 2 14 3 L5 4 S I 5 S2 •6 More than 1 r o o t ( s p e c i f y ) 7 P e r i p h e r a l n e r v e l o s s - s p e c i f y 120 LOSSR* of l o s s ( r i g h t ) Type 0 No l o s s 0 1 Conforms w e l l t o dermatome i n d i c a t e d 1 2 Does n o t conform t o expected dermatome 2 3 H y p e r e s t h e s i a 3 4 Hypo o r a n e s t h e s i a 4 5 1 + 3 5 6 1 + 4' 6 7 2 + 3 7 . 8 2 + 4 9 O t h e r ( s p e c i f y ) 121 S e n s a t i o n l e f t - l e v e l of. Impairment SENSL* None L3 L4 L5 SI S2 More than 1 r o o t ( s p e c i f y ) P e r i p h e r a l nerve l o s s •• spc : i f y 122 LOSSL* Type of . Ioss _ ( l e f t | 0 No l o s s 1 Conforms w e l l t o dermatome i n d i c a t e d 2 Does not conform t o ex p e c t e d dermatome 3 H y p e r e s t h e s i a 4 Hypo or a n e s t h e s i a 5 1 + 3 6 1 + 4 7 2 + 3 8 2 + 4 9 Other ( s p e c i f y ) LOSSRL i s combination o f two s i d e s . 123 -TENDERON Most prominent s i t e o f t e n d e r n e s s r* 0 None - 1 Spinous p r o c e s s 2 S . l . j o i n t r i g h t 3 S . l . j o i n t l e f t 4 R i g h t b u t t o c k 5 L e f t b u t t o c k 6 R i g h t p a r a v e r t e b r a l muscles ( s p e c i f y l e v e l ) 7 L e f t p a r a v e r t e b r a l muscles ( s p e c i f y l e v e l ) 8 G r e a t e r t r o c h a n t e r ( s p e c i f y s i d o ) 242. 124 Secondary s i t e o f t e n d e r n e s s 0 None TENDRTWO* i Spinous p r o c e s s TENDER i s a combination: n o r m a l / 2 S . l . j o i n t r i g h t one p l a c e tender/two s i t e s t e nder. . 3 S . l . j o i n t l e f t 4 R i g h t b u t t o c k 5 L e f t b u t t o c k 6 R i g h t p a r a v e r t e b r a l m u s c l e s ( s p e c i f y l e v e l ) 7 L e f t p a r a v e r t e b r a l muscles ( s p e c i f y l e v e l ) 8. G r e a t e r t r o c h a n t e r ( s p e c i f y s i d e ) 9 O t h e r , s p e c i f y • 125 S p i n o u s p r o c e s s t e n d e r n e s s l e v e l ( i f n o t l o c a l i s e d , g i v e c e n t r a l l e v e l ) 0"" No s p i n o u s p r o c e s s t e n d e r n e s s TENDLOC i B 2 L2 3 L3 4 L4 5 L5 6 SI 7 Over a s p i n o u s p r o c e s s but o b v i o u s l y more s u p e r f i c i a l i n s c a r 9 Other - s p e c i f y 126 M o t i v a t i o n f o r s u r g e r y 0 No s u r g e r y MOTIV* 1 P a t i e n t demanded i t 2 P a t i e n t i n i t i a l l y r e f u s e d i t "3 Surgeon'suggested i t , a f t e r " f a i l u r e o f c o n s i d e r a b l e c o n s e r v a t i v e t h e r a p y 4 Surgeon s t r o n g l y suggested i t , a f t e r l i t t l e c o n s e r v a t i v e t h e r a p y 9 Other - s p e c i f y 127 P a t i e n t ' s o p i n i o n o f s u r g e r y ( l a s t o p e r a t i o n o n l y ) 0 No s u r g e r y OPINION* i Permanent d e f i n i t e improvement 2 Permanent p a r t i a l improvement 3 No improvement 4 Temporary improvement f o r l e s s t h a n 2 y e a r s 5 Temporary improvement f o r a l o n g e r p e r i o d o f t i m e 6 Some wor s e n i n g 7 D e f i n i t e l y worse 9 O t h e r - s p e c i f y 128 Under t h e same c i r c u m s t a n c e s , t h e p a t i e n t would now; AGAIN* . ? J° S U f S e r y ' ,< — 1 A c c e p t s u r g e r y a g a i n 2 Refuse s u r g e r y a g a i n 3 Undecided 243. 129 P a t i e n t ' s u n d e r s t a n d i n g o f main r e a s o n s f o r s u r g e r y 0 No s u r g e r y 1 Does not know - p u r e l y on surgeons recommendation 2 To r e l i e v e p a i n 3 To p r e v e n t f u r t h e r t r o u b l e 4 To improve weakness ' -5 To improve back f u n c t i o n ^ 9 Other - s p e c i f y • 130 Examiner's_ o p i n i o n 0 Mo s u r g e r y OBJECT* P a t i e n t d e f i n i t e l y improved ;-' 2 P a t i e n t p a r t i a l l y improved $ 3 Worsening as a r e s u l t o f s u r g e r y 4 Worsening as a r e s u l t o f p r o g r e s s i v e d i s c d i s e a s e 5 Worsening as a r e s u l t o f e m o t i o n a l d i s e a s e 6 Worsening as a r e s u l t o f some o t h e r d i s e a s e 7. Temporary improvement, now w o r s e n i n g 9 Other - s p e c i f y Surgeons p r e o p e r a t i v e d i a g n o s i s ? 131 P a t h o l o g y found a t s u r g e r y ( l a s t . o p e r a t i o n ) 0 No o p e r a t i o n PATH* 1 No a b n o r m a l i t y seen . " 2 ' B u l g i n g d i s c 3 HSnisted d i s c • : 4 P s e u d a r t h r o s i s 5 F i b r o s i s and s c a r r i n g i n c a n a l 6 C o n g e n i t a l ''an<M»sly ( i n c l u d e s p o n d y l o l y s i s ) 7 C a ^ b i r ^ t i o r . o f more than one o f above 8 Surgeon's r e p o r t n o t a v a i l a b l e .. . 9 Other - s p e c i f y 132 K i g i t j j l f t . .vs**tg;brae o r i n s t a b i l i t y 133 P a t h o l o g i c a l e x a m i n a t i o n 0 N e i t h e r -0 No s u r g e r y MICRO* KISS* " 1 K i s s i n g s p i n e s ( s p e c i f y l e v e l ) 1 Normal d i s c t i s s u e 2 V e r t e b r a l i n s t a b i l i t y 2 D e g e n e r a t i v e d i s c 3 B o t h ' o f above 3 Not a v a i l a b l e 4 No d i s c e c t o m y 5 No t i s s u e examined 9 Other - s p e c i f y O r t h o p a e d i s t s ' R a t i n g of P s y c h o l o g i c a l f a c t o r s ? A l l r a t i n g s a r e done on a 7 - p o i n t continuum from l e a s t t o most. 134 I n y o u r r e l a t i o n s h i p I n t r o v e r t 1 2 3 4 5 6 7 E x t r a v e r t • ' OVERT I n t r o v e r t = shy,• w i t h d r a w i n g , s o c i a l l y u n c o m f o r t a b l e 135 Dependent 1 2 3 4 5 6 7 Independent Dependent = subject- seems t o g e t some s o r t o f e m o t i o n a l OPEND g r a t i f i c a t i o n and c l i n g s t o you l i k e a c h i l d m i g h t . 244. Passive - Aggressive not at a l l 1 2 3 4 5 6 7 very much so P.A. «= (very much so) - po.ti.ent complies with your requests that apparently displease him, but you get the impression he's " g e t t i n g back at you" by not complying f u l l y . 137 Submissive 1 2 3 4 5 6 7 Dominant OPOWER Submissive = p a t i e n t a c c e p t i n g l y goes along w i t h a l l your requests, allows you to i n i t i a t e t o p i c s Dominant = pa t i e n t tri.es to ' steer' p a rts of the d i s c u s s i o n i examination 136 OPA 138 Eagerness i n recounting h i s t r o u b l e s OBITCH l i t t l e 1 2 3 4 5 6 7 very. 139 E m o t i o n a l i t y i n recounting t r o u b l e s ( i s he l i k e a bleeding-heart) l i t t l e 1 2 3 4 5 6 7 very OBLEED 1/iD Anxiety i n approaching you as as a u t h o r i t y or f a t h e r f i g u r e l i t t l e 1 2 3 4 5 6 7 very much OANXIETY 141 Anxiety i n the stage or course of h i s pathology l i t t l e 1 2 3 4 5 6 7 very rauch SANXIETY l i t t l e - i n d i f f e r e n c e 142 Estimate of verbal a b i l i t y low 1 2 3 4 5 6 7 high OWORD 143 Estimate of I.Q. IQ has a mean of 100, standard d e v i a t i o n of 15. low (70) 1 2 3 t 5 6 7 high 130 OTRUTH t n o m a l average 1 Cold toloranoa time ......... State r i g h t or l e f t hand Comment on p a t i e n t ' s r e a c t i o n soconds. CT1* HANDED 245. Column. 2 3-8 9-13 H NUMBER* Back Surgery Study - Xray Assessment. Dr. Peter Wing. Patient l.D. Card 1 Hospital Record Number D.V.A., W.C.B. or other number •••• Xray number • Number of vertebrae 1 - 4 distinct lumbar vertebrae 2 - 5 * • • 3 - 6 • • 8 4. - incomplete transition of a sixth lumbar vertebra. 5 - hemivertebra Describe anomalies: 15 Sacral anomalies  SACRAL* o - none 1 - congenital 2 - acquired 16 Separate facet epiphyses  FACETS* o _ n o n e 1 - L l 2 - L2 3 - W Describe: A - U 5 - 15 6 - SI 7 - a combination - specify. State side, whether superior or inferior facet: 246. Column 17 SCOLIOS* 18 LYSIS* 19 LISTHES-" Scoliosis 0 - none Describe and measures 1 - 10-20° 2 - over 20° Spondylolysis - specify aide 0 - none 4 - L4 1 - L l 5 - L5 2 - L2 6 - SI 3 - L3 7 - other Spondylolisthesis - specify type by cause i f possible. 0 - none seen 1 - grade 1 2 - grade 2 3 - grade 3 4 - grade 4 20 PROSIS 21 FRACTURE* Osteoporosis 0 - none seen 1 - grade 1 2 - grade 2 3 - grade 3 Fracture 0 - none 1 - probably old. 2 - probably new 4 - grade 4 5 - grade 5 6 - localised osteopenia - specify. Describe type and level. 247. Column 22 DYE 23 LAMINEGT* Myelogram dye 0 - none seen 1 - few drops 2 - moderate amount Evidence of laminectomy ( posterior with bone removal - describe), 0 - none seen 1 - L l 2 - 12 3 - L3 4 - U 5 - L5 6 - SI 7 - Combination - specify. 24 Evidence of fusion FUSION* 0 - none seen 5 - anterior interbody 1 - posterior bone block 6 - 1 + 2 2 - Boucher's type 7 - 1 +• 4 3 - posterolateral 8 - other combinations - specify 4 Also separated - apophyseal screws i n t o d i f f e r e n t types of fus i o n 9 - other types - specify (FUSI0N1, FUSI0N2, FUSI0N3, etc.) 25 Level of fusion LEVEL* 0 - no fusion 5 - L4 5 1 - L5S1 6 - L3 5 2 - L4S1 7 - L3 4 3 4 - L3S1 LEVELA - L2S1 LEVELB 9 - other specify. Number of segments fused. No recombination. 26 S o l i d i t y of f u s i o n SOLID (0 1 - no fusion - n°t used) - solid fusion 2 - pseudarthrosis. ( a t e i t h e r level, i f two are fused) Specify level (s) and cr i t e r i a . 248. Column 27 SCREWS 28 SCREWED* 29 SCHMORL 30 KHUTSSON 31 DEOEN Screws number present 0 - none 1 - 1 2 - 2 3 - 3 Screws abnormalities. 0 - none 1 - normal 2 - bent 3 - broken Schmorl's nodes 0 - none 1 - one site 2 - more than one site Knutsson's sign 0 - not seen 1 - L5S1 only 2 - other sites - specify Posterior .joint degeneration 0 - none 1 - 1 level, 1 side 2 - 1 level, bilateral 3 - more than 1 level. U 5 6 7 5 6 more than 6 Specify level and describe Specify site(s) and side. 249. Column 32 Traction spurs of anterior longitudinal ligament  SPURS 0 - none 1 - present at 1 site 2 - present at more than 1 site Specify levels and position. 33 Osteophytes  OSTEOPHY 0 - none 1 - localised 1 site 2 - more than 1 site Detail sites. Ligamentous calcification. 0 - none 1 - localised 1 level 2 - more than 1 level Specify position and site. Kissing vertebral spines ( Baastrup's phenomenon ) 0 - none Specify levels. 1 - 1 level 2 - 2 levels 3 - 3 levels U - U levels Other skeletal pathology e.g. Paget's, Ca. 0 - absent 1 - present 34 LIOCALC 35 BAASTRUP 36 SKELEX 250. Column 37-39 40-43 44-47 48-51 52-55 56-59 68 69 70 71 72 LANGLE Lumbosacral angle - degrees. Disc height L12 L23 L34 U 5 L5S1 front P back B DISCI  DISC2  DISC3  DISC**  DISC 5 DISCMEAN mean of a l l paired measurements (i.e. both front and back recorded). Posterior joint subluxation in mm. above .joint-body line. 60-61 LUXl L12 62-63 LUX2 123 64-65 LUX3 L34 66-67 LUXlf U 5 LUXMEAN mean of Retrospondylolisthesis ( in mm, measured posteriorly). RETR01 L12 123 L45 RETR02  RETR03 RETROD RETROAVC L5S1 mean of a l l levels. Interpedicular distance in mm. 73-74 IPED1 L l 75-76 IPED2 L2 77-78 IPED3 L3 79-80 IPED4 U 9-10 IPED5 L5 IPEDAVO mean of a l l levels. 251 . Column S a g i t t a l diameter of canal I n mm. 11-12 SAG1 L l 13-14 SAG2 L2 15-16 SAC3 L3 17-18 SAGft U 19-20 SAG5 L5 21-22 SAG6 SI SAGMEAN mean of a l l l e v e l s BODYl L 1 B0DY2 L 2 B0DY3 L 3 BODYlt L U Body Height Front Back F B B0DY5 L 5; BODYMEAH mean of a l l paired measurements (both f r o n t and back measurable). 252. APPENDIX 2. PSYCHOLOGICAL DATA COLLECTION FORM For details of the psychological data analysis and variable refer to WILFLING279. 253. BACK STUDY FORMAT ** PSYCHOLOGY ** WILFLING Spaces Code Datum Name Date of Exam. (3) Subject # (1) Sex Male 1 Female 2 Date of B i r t h / I  (2) Blank (2) Age in years (2) - . P o s i t i o n i n b i r t h order, from o l d e s t . (1) P o s i t i o n i n b i r t h order, i f : 1 oldest 2 intermediate 3 youngest 4 • only c h i l d (2) • Province of b i r t h 0 not Canada 6 Quebec 1 B. C. 7 KB 2 A l b e r t a 8 NS 3 Sask. 9 PEI It Manitoba TIO N f l d 5 Ontario 11 NOT , (1) Size of conmunityS grew up i n ( use estimate of s i z e i f several moves - most important between 10 and l e a v i n g home): 1<500 6 10,000 - 25,000 2 500 - 1,000 7 25,000 -100,000 3 1,000 - 2,500 8 > 100,000 k 2,500 - 5,000 9 can't estimate, many moves '5 5,000 - 10,000 (2) _____ Occupation of f a t h e r : 0 no f a t h e r 1 farmer ( owner ) 2 own small business ( l i k e corner store) 3 own l a r g e business k p r o f e s s i o n a l ( lawyer, Doctor, engineer, etc) 5 semi-professional ( teacher, accountant ) 6 c l e r g y 7 salesman • 8 b l u e - c o l l a r ( c l e r k , agent, etc.) 9 minor supervisor ( working ) 10 Bervice employee 11 l a b o r e r 12 unemployed 13 other lk major supervisor / 254. Spaces Code Datum (1) Parents r e l i g i o u s ? 0 Ho 1 very 2 moderately 3 a l i t t l e k one parent no, other 1 or 2 5 very moral, but not r e l i g i o u s (only i f given spontaneously. (2) How d i d parents get along? 1-70 scale (2) How happy was childhood? 1-70 s c a l e 8) Any member of f a m i l y " s i c k l y " ? I n d i c a t e i n separate columns up to 3 of : (1) 0 none 5 grandparent 1 f a t h e r 6 uncle, aunt 2 mother 7 cousin 3 same sexed s i b 8 unrelated member of household k opp. sexed s i b (2) • At what age d i d S leave home permanently? ( years ) (2) _____ Number of years of grade school completed (1) ______ 1 Number of years U n i v e r s i t y (2) _____ 2 months of v o c a t i o n a l school ( l ) 3 years of apprenticeship (l) _____ I n the three above, i n d i c a t e completeness: 0 didn't do any of 1-3 1 completed 2 incomplete, withdrew ( q u i t w i t h l i t t l e roason) 3 incomplete, was ejected k moved down i n order above and completed 5 " ". " " " " didn't complete 6 moved up i n order above and completed 7 " " " " " " didn't complete . 8 withdrew due war, lack of funds 9 withdrew due h e a l t h , emotional reasons ( l ) _____ What was f a v o r i t e subject i n school ? ( code below ) ( l ) ______ What was most d i s l i k e d subject i n school ? 0 can't answer 1 math 2 a science 3 E n g l i s h or a language k history/geography. 5 c l e r i c a l 6 shop work, a g r i c u l t u r e , home economics 7 eports 8 a r t - p a i n t i n g , music, drama 9 other 255. XXj Datum Religiousness 0 never have been r e l i g i o u s 1 I- always have been r e l i g i o u s 2 . have changed to more r e l i g i o u s 3 have changed to le s s r e l i g i o u s k remained r e l i g i o u s , but changed f a i t h s S e r v i c e 0 none 1 WV/2 didn't see b a t t l e 2 VW2 did see b a t t l e 3 Korea didn't see b a t t l e 4 Korea d i d see b a t t l e 5 - b o t h , didn't see b a t t l e 6 both, d i d see b a t t l e 7 peacetime forces only Present m a r t i a l s t a t u s : ^ , 0 s i n g l e 3 separated 1 ' married 4 divorced 2 widowed 5 common-law Past m a r i t a l record ( excluding the above); 0 nothing t o add 6 three or more separations 1 one divorce 7 one past comnon-law wife 2 two divorces 8 two or more past common-law 3 widowed once- or more wives 4 . one separation 9 refuses to t a l k 5 two separations Status of present m a r i t a l r e l a t i o n s h i p : 0 there i s n ' t one 1 ready to break up 2 would break up i f not f o r c h i l d r e n 3• stormy but w i l l remain i n t a c t 4 • i n d i f f e r e n t 5 about average 6 above average 7 superb 9 refuses to discuss Sex l i f e . 0 not exposed to one 1 l i t t l e i n t e r e s t , mutual 2 l i t t l e i n t e r e s t , spouse f r i g i d or impotent 3 l i t t l e - spouse has other d i f f i c u l t y 4 l i t t l e - S not i n t e r e s t e d ( f r i g i d or impotent) 5 l i t t l e - because of S's back 6 l i t t l e - because of S's o t h e r . t r o u b l e s 7 moderate - mutual 8 moderate - spouse's l a c k of i n t e r e s t 9 moderate -.spouse's other troubles 10 . moderate - S's l a c k of i n t e r e s t 11- moderate - S's back ... 12 moderate - S's other troubles 13 A l l ' s w e l l 14 refuses to di s c u s s . 256. Spaces Code Datum (l) Number of c h i l d r e n a t home now 0-9 9=9 or more ( l ) _____ Does S support anyone else ? (1) 0 no ( l ) 1 parent or grandparent 2 " " " of spouse 3 s i b k s i b of spouse 5 removed r e l a t i v e 6 " " o f spouse 7 c h i l d of r e l a t i v e 8 c h i l d of spouse's r e l a t i v e 9 unrelated c h i l d or adul t (l) • Does S own home or apartment ? 0 no 1 yes, la r g e mortgage > $ 10,000. 2 yes, moderate mortgage 5-10,000 3 yes, small mortgage < 5»0C0 4 yes, c l e a r t i t l e (1) _ . Has S ever owned a home ? ~~ 0 no 1 yes - had to give i t up f o r f i n a n c i a l reasons 2 yes - gave i t up because of other d i f f i c u l t i e s 3 yes - gave i t up f o r sake of. convenience (2) _____ Income to S's f a m i l y per month i n $ 100's ( Gross ) ( l ) _______ Source of income ( l ) 0 no income ( f o r sources 2,3,) (l) ______ 1 business ownership 2 investments 3 S works 4 spouse works 5 pension 6 parents 7 • c h i l d r e n 8 welfare 9 S, won't say ( l ) _____ Does £> think that p e r s o n a l i t y or ps y c h o l o g i c a l status can have a bearing on the existence of or the experience of a back problem ? 0 no yes,,a l i t t l e yes, a moderate amount s e l f reference J 3 yes» qui t e a b i t not now, but used to have a b i t not now, but used to have a moderate amount not now, but used to have a l o t to do with i t 7 not f o r s e l f , but f o r others a b i t 8 not f o r s e l f , but f o r others a l o t 9 _ w i l l not give a d i r e c t answer Elaborate on back i f j3 thinks psych, status e f f e c t s him 257. Code Datum Has S ever hsd p s y c h i a t r i c a t t e n t i o n ? 0 no 1 - 8 9° 9 or more times DSM-2 codes f o r major disorders ( l e t 000 = no disorder ) When f i r s t psych, a t t e n t i o n ? ( years ago ) When l a s t psych, a t t e n t i o n ? ( years ago; 0= K. 1 y r . or none) Has anyone i n S's f a m i l y had p s y c h i a t r i c a t t e n t i o n ? 0 no 1 grandparent 2 parent 3 sib lr- spouse 5 o f f s p r i n g 6 removed blood r e l a t i v e 7 in-law 8 unrelated " fa m i l y " member _____________________ DSM-2 codes f o r the immediately above, i n order given. How does S f e e l about taking part i n t h i s study? 0 no response 1 "• great d i s l i k e 2 minor d i s l i k e 3 i n d i f f e r e n t k g l a d to help 258. APPENDIX 3.  COLD TOLERANCE TEST PROCEDURE In a bowl of suitable size, in this case, a two-gallon plastic bucket, enough water is placed to three-quarter f i l l the vessel. A standard tray of ice is added and the whole thing covered with a cloth and allowed to equilibrate for perhaps twenty or thirty minutes. It should really be standardized with a thermometer. Instructions to the Patient It should be kept standardized to keep the motivational aspect of the instructions constant. The patient's dominant hand should be used for the study and he should not be encouraged to talk while the study i s in progress. Instructions should be standardized and might be as follows: "Different people feel different amounts of pain and I would like you to try a simple test of this. I would like you to immerse your dominant hand up to the wrist in this bowl of ice water. Keep your hand palm down and with the fingers open. Keep your hand in the water as long as you can reasonably bear i t but not to the point of suffering unreasonable pain. While your hand is in the water think about sensations in your hand and after you have taken i t out you can t e l l me about these. 259. Okay, go ahead, and remember to keep your hand i n the water as long as you can." The time should be recorded i n seconds. No patient should be allowed to keep his hand in the water for more than three minutes as after this time he may develop an anesthetic-type of response and the time w i l l not be reliable while the patient himself may suffer harm. It may be of interest to record the patient's response on the l e f t hand and right hand but the dominant hand should be noted and should probably be done f i r s t otherwise a learning synonym w i l l be incorporated. 260. APPENDIX 4. PSYCHOLOGICAL SCALES CALIFORNIA PERSONALITY INVENTORY SCALES - NAMES AND IMPLICATIONS96 The California Personality Inventory i s designed to assess "normal" functioning, especially social functioning, rather than to screen out the "abnormal" personality. 1. Do (dominance). 2. Cs (capacity for status). Drive, a b i l i t y to communicate. 3. Sy (sociability). Social activity, popularity. 4. Sp (social presence) 5. Sa (self-acceptance) 6. Wb (sense of wellbeing). Health and v i t a l i t y , feeling of physical fitness. 7. Re (responsibility). Responsibility, positive character integration. 8. So (socialisation). "Good citizens" vs. "bad citizens". 9. Sc (self-control). Lack of impulsiveness. 10. To (tolerance). Fairmindedness and humanitarianism vs. fascism, authoritarianism. 11. Gi (good impression). Creation of a good impression, strong correlation with K scale of M.M.P.I. 261 . 12. Cm (communality). Dependable, practical, has common sense vs. is at odds with himself 13. Ac (achievement via conformance). High school grades, e f f i -ciency . 14. Ai (achievement via independence). Self-reliant, independent in judgement, able to think for himself. 15. Ie (intellectual efficiency). High correlation with intellectual assessments. 16. Py (psychological-mindedness). 17. Fx ( f l e x i b i l i t y ) . F l e x i b i l i t y vs. r i g i d i t y . 18. Fe (feminity). Correlates well with MMPI MF scale. MINNESOTA MULTIPHASIC PERSONALITY INVENTORY SCALES - NAMES AND  IMPLICATIONS93 THE VALIDITY SCALES "L" scale - l i e scale. The subject wishes to 'appear good' by answering in the negative when questioned regarding (for example) a socially undesirable mannerism common to a l l . Must be considered with c l i n i c a l scales. "F" scale - indicates carelessness or lack of understanding or cooperation. Item always answered in a particular direction. Known as 'Fake' scale as subjects wishing to put themselves i n a bad light 262. w i l l show a high score here. "K" scale - represents defensiveness as a test-taking attitude is incorporated as a correction i n some of the c l i n i c a l scales. K i s correlated with socioeconomic status and amount of education. It may be useful c l i n i c a l l y in that a lower K score indicates willingness to accept treatment situations. THE CLINICAL SCALES 1. (Hs). Known as hypochondriasis formerly, but better thought of as index of the importance of bodily functions and symptoms to the particular person. May show undue concern about health, or complain about pain and disorders which are hard to find and for which no clear organic basis can be found. Elevated i n those with demonstrable physical disorder, a score over 65 suggests ex-aggeration. 2. (D). Reflects the characteristics of depression, may be ele-vated in those with severe organic illness or with insight into a mental illness. Combination with elevated score on F suggests suicidal risk. 3. (Hy). Hysteria. Those with high 3 scores are more immature psychologically than any other group. Under stress they are l i k e l y to develop physical symptoms. The neurotic triad (scales 1, 2 and 3) from the most 263. notable feature of the profile i n the patient with illness of a dominantly hysterical pattern. The "conversion V" refers to ele-vation of 1 and 3 with 2 lower. Operative and other radical phys-i c a l treatment of patients whose profiles show a conversion V as a feature of an elevated neurotic triad should only be undertaken after careful evaluation of a l l possible psychological factors and functional components. Scale 3 may be low in the occasional patient when his conversion symptom is "working" or manifest. (Pd). Psychopathic deviate. These people are marked by the absence of deep emotional response, i n a b i l i t y to form warm per-sonal attachments and disregard of social mores. Likely to be higher in adolescents and young adults and low i n the s t r i c t l y religious. (Mf). This is a measure of masculine or feminine interest patterns, a high score indicating a tendency towards interests usually associated with the opposite sex. I n i t i a l l y derived from a group of homosexuals (not necessary practicing), the scores for college men, for example, are somewhat higher than other groups, with seminary students and those in a r t i s t i c and literary fields scoring highest. (Pa). Paranoia. Extreme elevations on this scale are most likdy to be observed in paranoid schizophrenia; . persons with an ex-cessive amount of paranoid suspiciousness are common and i n many 264. situations not especially handicapped. However, persons receiving high scores on this scale have to be handled with special care. False negatives may result i f a paranoid person wishes to conceal his di s a b i l i t y : an abnormally low score may result. (Pt). Psychasthenia. A high score on this scale reflects com-pulsive or phobic t r a i t s . This correlates highly with scale 8. (Sc). Schizophrenia. This scale measures the similarity of the subject's responses to those of patients who are characterised by bizarre and unusual thoughts or behaviour. It distinguishes about 60% of observed cases diagnosed as schizophrenia, but does not identify some paranoid types of schizophrenia (which usually score high on 6) and some with a pure schizoid type of behaviour. Simple schizophrenics are more li k e l y to obtain a generally ele-vated profile with scale 1 high. A high score on scale 8 i n a c l i n i c a l l y normal individual is consistent with a 'withdrawn' person, who does not come into severe adverse contrast with his environment. High 8 scores should be evaluated in the light of the other scales. (Ma). Mania. The scale measuring the personality factor char-acteristic of persons over-productive in thought and action. The borderline between normal and abnormal is wide, and other scale elevations must be taken into consideration in i t s interpretation. A high 9 scale may be an asset to a person who wishes to be ex-trovertive and active. 265. THE RESEARCH SCALES In this study three scales not included in the c l i n i c a l scales have been used. Si. (Social introversion-extroversion). A popular scale, high scores being indicative of introversion or avoidance of social contacts with others. Es. (Ego-strength). Of use in and developed as a predictor of favorable response to psychotherapy, this scale includes items concerning physical functioning, s t a b i l i t y , personal adequacy, phobias. Lb. (Low back pain). Constructed on the basis of 25 MMPI items which differentiated between patients with low back pain diag-nosed to be due to a protruding intervertebral disc (the "organics") and those whose low back pain had not been diagnosed as resulting from an organic disease (the "functionals"). The "functionals" had a conversion V pattern (see scale 3) with a secondary peak as scale F; the mean "organic" profile showed nearly equal scales 1, 2 and 3 slightly higher than the rest of the profile. A high score on the Lb scale is suggestive of "functional" low back pain. A "cutting point" of 70 (T score) i s used c l i n i c a l l y to 106 place the individual patient into the appropriate group; HANVIK found a high degree of r e l i a b i l i t y in the scale. 266. APPENDIX 5. THE BECK INVENTORY OF DEPRESSION 267. HAMEJ D.I.t s i A. 0 I do not f e e l sad 1 I f e e l blue or sad 2a I am blue or sad a l l the time and I can't snap out of i t 2b I am so sad or unhappy that i t i s very p a i n f u l 3 I am so sad or unhappy t h a t . I can't stand i t B. 0 I am not p a r t i c u l a r l y p e s s i m i s t i c or discouraged about the future 1 I f e e l discouraged about the future 2a I f e e l I have nothing to look forward to 2b I f e e l that I won't ever get over my troubles 3 I f e e l that the future i s hopeless and that things cannot improve C 0 I do not f e e l l i k e a f a i l u r e 1 . I f e e l l i k e I have f a i l e d more than the average person 2a I f e e l I have accomplished very l i t t l e that i s worthwhile or that means anything' 2b As I look back on my l i f e a l l I can see i s a l o t of f a i l u r e s 3 I f e e l I am a complete f a i l u r e as a person ( parent, husband, wife) D. 0 I am not p a r t i c u l a r l y d i s s a t i s f i e d l a I f e e l bored most of the time l b I don't enjoy things the way I used to 2 . I don't get s a t i s f a c t i o n out of anything anymore 3 1 am d i s s a t i s f i e d with everything E. 0 I don't f e e l p a r t i c u l a r l y g u i l t y 1 I f e e l bad or unworthy a good part of the time 2a I f e e l q u i t e g u i l t y 2b I f e e l bad or unworthy p r a c t i c a l l y a l l the time now 3 I f e e l as though I am very bad or worthless F. 0 I don't f e e l I am being punished 1 I have a f e e l i n g that something bad may happen t o me 2 I f e e l I am being punished or w i l l be punished 3a I f e e l I deserve to be punished 3b • I want to be punished G 0 I don't f e e l disappointed i n myself l a I am disappointed i n myself lb 1 don't l i k e myself 2 I am disgusted with myself 3 I hate myself H 0 I don't f e e l I am any worse than anybody e l s e 1 I am very c r i t i c a l of myself f o r my weaknesses or mistakes 2a I blame myself f o r everything that goes wrong -2b I f e e l I have many bad fault3 268. I . 0 I don't have any thowhts of harming myself 1 I have thoughts of harming myself but I would not carry them out 2a I f e e l I would bo b e t t e r o f f dead 2b 1 have d e f i n i t e plans about committing s u i c i d e 2c I f e e l my fa m i l y would be b e t t e r o f f i f I were dead 3 I would k i l l myself i f I could J , 0 1 don't cry any more than usual 1 I cry more now than I used to 2 I cry a l l the time now„ I can't stop i t 3 I used to be able t o cry but now I can't cry at a l l even though I want to E. 0 I am no more i r r i t a t e d now than I ever am 1 I get annoyed or i r r i t a t e d more e a s i l y than I used t o 2 I f e e l i r r i t a t e d a l l the time 3 I don't get i r r i t a t e d at a l l at the things that used to i r r i t a t e me L. 0 I have not l o s t i n t e r e s t i n other people 1 I am l e s s i n t e r e s t e d i n other people now than I used to be 2 • I have l o s t most of my i n t e r e s t i n other people and have l i t t l e f e e l i n g fx>r them 3 I have l o s t a l l my i n t e r e s t i n other people and don't care about them at a l l M» 0 I make decisi o n s about as w e l l as ever 1 I am l e s s sure of myself now and t r y to put o f f making deci s i o n s 2 I can!t make decisions anymore without help 3 I can't make any de c i s i o n s at a l l any more H. 0 I don't f e e l I look any worse than I used t o 1 I am worried t h a t I am l o o k i n g o l d or u n a t t r a c t i v e 2 . I f e e l that there are permanent changes i n my appearance and they make me look u n a t t r a c t i v e 3 1 f e e l t h a t I am ugly or r e p u l s i v e l o o k i n g 0, 0 I can work about as w e l l as before l a I t takes e x t r a e f f o r t t o get s t a r t e d at doing something lb I don't work as w e l l as I used to 2 I have to push myself vary hard to do anything 3 I can't do any work at a l l P» 0 I can sleep as w e l l as usual 1 I wake up more t i r e d i n the morning than I used to 2 I wake up 1-2 hours e a r l i e r than usual and f i n d i t hard to get back to sleep 3 I wake up e a r l y every day and can't get more than 5 hours sleep Q. 0 I don't get any more t i r e d than usual 1 I get t i r e d more e a s i l y than I used to 2 I get t i r e d from doing anything 3 I get too t i r e d to do anything 269. R. 0 My a p p e t i t e i s no w o r s e t h a n u s u a l 1 My a p p e t i t e i s n o t as good as i t u s e d t o be 2 My a p p e t i t e i s m u c h . w o r s e now 3 I h a v e no a p p e t i t e a t a l l anymore S. 0 I h a v e n ' t l o s t much w e i g h t , i f a n y , l a t e l y 1 I h a v e l o s t more t h a n 5 pounds 2 I h a v e l o s t more t h a n 10 pounds 3 I h a v e l o s t more t h a n 15 pounds T, 0 I am no more c o n c e r n e d a b o u t my h e a l t h t h a n u s u a l 1 I am c o n c e r n e d abou t a c h e s and p a i n s o r u p s e t s t o m a c h o r c o n s t i p a t i o n o r • o t h e r u n p l e a s a n t f e e l i n r s i n my b o d y 2 I am s o c o n c e r n e d w i t h how I f e e l o r what I f e e l t h a t i t ' s h a r d t o t h i n k o f much e l s e 3 I am c o m p l e t e l y a b s o r b e d i n what I f e e l XSa 0 I h a v e n o t n o t i c e d any r e c e n t change i n my i n t e r e s t i n s e x 1 I am l e s s i n t e r e s t e d i n s e x t h a n I u s e d t o b e 2 I am much l e s s i n t e r e s t e d i n s e x now 3 I-have l o s t i n t e r e s t i n s e x c o m p l e t e l y 270. APPENDIX 6. THE KILPATRICK-CANTRIL SELF-ANCHORING SCALE (modified appropriately) 271 . Put the K-C sheet i n f r o n t of the subject and give the f o l l o w i n g i n s t r u c t i o n s verbatimt T h i s i s a s e l f - p e r c e p t i o n s c a l e . What I would l i k e you to do i s to t h i n k f o r a moment what f o r you would be an i d e a l l i f e s i t u a t i o n . Tfaat I mean by t h i s is» what are your goals, a s p i r a t i o n s - what would you l i k e t o a t t a i n i n l i f e t hat would make you happy? A f t e r you've thought i t over f o r a minute, would you please g i v e me a b r i e f d e s c r i p t i o n over here? ( i n d i c a t i n g w i t h p e n c i l ) . A f t e r that I would l i k e you to stop and t h i n k of what f o r you would be the v e r y worst l i f e s i t u a t i o n . By t h i s I mean a set of circumstances t h a t you could• imagine y o u r s e l f b e i n g - i n , but that you-most, c e r t a i n l y wouldn't, want to be a p a r t o f . A f t e r you've thought.-it over .for a minute, would you please give a b r i e f d e s c r i p t i o n of those circumstances i n these spaces? ( i n d i c a t i n g with p e n c i l ) . A f t e r you've done t h a t , w e ' l l come over here ( i n d i c a t i n g with p e n c i l ) and lo o k at t h i s ten-step ladder f i g u r a t i v e l y as the ladder of l i f e . , with the i d e a l l i f e s i t u a t i o n a t the top and the worst l i f e s i t u a t i o n at the bottom. I ' l l ask you t o show me where on the ladder you are now, where on the ladder you were j u s t before your back problem s t a r t e d , and f i n a l l y where on the ladder you th i n k y o u ' l l be i n 5 years from now. Ri g h t now, though, I'd j u s t l i k e you to t h i c k about and describe the i d e a l l i f e s i t u a t i o n and the worst l i f e s i t u a t i o n f o r you ( i n d i c a t i n g with p e n c i l ) , and then w e ' l l do the r e s t t o gether. n I t i s a good p r a c t i c e to absent oneself from the room f o r about 5 minutes at t h i s time, because most subjects t r y to t a l k during the task. Before l e a v i n g make c e r t a i n the subject understands the task and as .no n - d i r e c t i v e l y as p o s s i b l e ansvver s p e c i f i c questions or overcome ob j e c t i o n s . 272. R e t u r n i n g a f t e r about 5 minutes' absence ( the time taken to smoke a c i g a r e t t e ) , wait unobtrusively i f necessary, f o r the subject to complete the t a s k and then continue : "Okay. Now, i f we come over here to the ladder ( i n d i c a t i n g with p e n c i l ) and regard i t as the ladder of l i f e w ith t h i s ( i n d i c a t i n g w r i t t e n d e s c r i p t i o n ) , the i d e a l l i f e s i t u a t i o n at the top, and t h i s ( i n d i c a t i n g w r i t t e n d e s c r i p t i o n ) the-worst l i f e s i t u a t i o n , • a t the bottom, could you show me with an arrow on the (subject' I l e f t of the ladder ( making a sweeping motion with the p o i n t e r p e n c i l so a p o i n t i s not suggested)where you are now." A f t e r the arrow i s placed by the s u b j e c t , ask him to w r i t e 1972 ( the present year) beside, i t . Then continue t "With another arrow, could you show me where on the ladder you were j u s t • before your back problem s t a r t e d . " A f t e r the arrow i s placed, ask the subj ect to l a b e l i t with the year h i s back problem s t a r t e d . And f i n a l l y , ask: "And f i n a l l y , could you show me with another arrow where you t h i n k y o u ' l l be on the ladder i n 5 years from now." L a b e l the f i n a l arrow with the year 5 years hence ( i . e . i n 1972, l a b e l 1977). 

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