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The Rehabilitation of the industrially injured meniscectomy patient : an evaluation Glazer, Alisa R. 1980

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The R e h a b i l i t a t i o n of the I n d u s t r i a l l y Injured Meniscectomy Patient: An Evaluation by ALISA ROSE GLAZER B.P.T., M c G i l l University 1970 B.Sc.P.T., M c G i l l University 1975 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE (Health Services Planning) • ...^  i n THE FACULTY OF GRADUATE STUDIES (Department of Health Care & Epidemiology) We accept t h i s thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA May 1980 © A l i s a Rose Glazer, 1980 I n p r e s e n t i n g t h i s t h e s i s i n p a r t i a l f u l f i l m e n t o f t h e r e q u i r e m e n t s f o r a n a d v a n c e d d e g r e e a t t h e U n i v e r s i t y o f B r i t i s h C o l u m b i a , I a g r e e t h a t t h e L i b r a r y s h a l l make i t f r e e l y a v a i l a b l e f o r r e f e r e n c e a n d s t u d y . I f u r t h e r a g r e e t h a t p e r m i s s i o n f o r e x t e n s i v e c o p y i n g o f t h i s t h e s i s f o r s c h o l a r l y p u r p o s e s may be g r a n t e d by t h e Head o f my D e p a r t m e n t o r by h i s r e p r e s e n t a t i v e s . I t i s u n d e r s t o o d t h a t c o p y i n g o r p u b l i c a t i o n o f t h i s t h e s i s f o r f i n a n c i a l g a i n s h a l l n o t be a l l o w e d w i t h o u t my w r i t t e n p e r m i s s i o n . D e p a r t m e n t o f H e a l t h . C a r e a n d E p i d e m i o l o g y The U n i v e r s i t y o f B r i t i s h C o l u m b i a 2075 W e s b r o o k P l a c e V a n c o u v e r , C a n a d a V6T 1W5 A p r i l 2 1 , 1 9 8 0 D a t e r ! 3 E - 6 B P 75-51 I E i i Abstract The r e h a b i l i t a t i o n center of the Workers' Compensation Board (WCB) of B r i t i s h Columbia provides a c e n t r a l i z e d , m u l t i d i s c i p l i n a r y , time-intensive approach to the treatment of the i n d u s t r i a l l y - i n j u r e d patient. In order to evaluate the effectiveness of th i s system, r e h a b i l i t a t i o n outcomes measured by the number of days postoperative before return to work were compared for three groups of meniscectomy patients. The f i r s t group comprised those patients treated at the WCB r e h a b i l i t a t i o n center (commonly ref e r r e d to as "the C l i n i c " ) . The second group were those WCB patients r e h a b i l i t a t e d i n community f a c i l i t i e s , and the t h i r d group were those WCB cases who received no formal postoperative p h y s i c a l therapy. The population studied, 454 cases, was a t o t a l sample of a l l cases from the Lower Mainland for whom the WCB paid surgeons medical aid for the performance of a meniscectomy i n 1976 and 1977. Data was obtained through an examination of the records. The variables examined were type of post-operative r e h a b i l i t a t i o n and of preoperative r e h a b i l i t a t i o n , age, occupation, income, degenerative changes of the knee, latency period, h i s t o r y of previous knee i n j u r y , medial or l a t e r a l e x c i s i o n of the meniscus and presence of a poste r i o r i n c i s i o n . The method of analysis was a m u l t i f a c t o r analysis of variance. Chi square was also used to understand the differences i n the population. One hundred f o r t y cases with complicated pathology or circumstances which might have influenced the r e s u l t s , and a l l 29 women i n the i n i t i a l sample, were excluded from the study. The f i n a l sample consisted of 285 cases: 85 C l i n i c cases, 110 Community cases, and 90 non-treated cases. The three populations were found to d i f f e r s i g n i f i c a n t l y i n three c h a r a c t e r i s t i c s : the frequency of degenerative changes of the knee, occupation, and the presence of a po s t e r i o r i n c i s i o n . There was a higher incidence of degenerative changes i n the C l i n i c group, and fewer cases with sedentary occupations i n the group treated i n the Community, The occurrence of post e r i o r i n c i s i o n was greater i n the Community than i n the other populations. Four men who took over 300 days return to work were removed from the l a t e r analyses. The mean return to work time for the C l i n i c group was found to be 105.0 days, for the Community group 86.4 days, and for non-treated patients 67.5 days. These differences were s i g n i f i c a n t at the .05 l e v e l . i i i Within each postoperative r e h a b i l i t a t i o n group, the subgroup preoperatlvely treated at the C l i n i c was found to have returned to work the l a t e s t . i With the exception of occupation, the other study v a r i a b l e s were not found to be s i g n i f i c a n t . With the Community-treated group only, the i n t e n s i t y of treatment was not found to a f f e c t return to work. It i s suggested that the C l i n i c environment may encourage attitudes of d i s a b i l i t y and dependency. Intensive therapy and a m u l t i d i s c i p l i n a r y approach to treatment may also encourage u n r e a l i s t i c expectations of ultimate "cure". C e n t r a l i z a t i o n of treatment may heighten a l i t i g i o u s atmosphere, It i s stressed that since return to work was the only c r i t e r i o n of outcome, other f u n c t i o n a l and pathophysiological outcomes remain unknown and long-term r e s u l t s were not studied. i v Table of Contents Page Abstract i i L i s t of Tables v i i i L i s t of Figures x Acknowledgements x i I INTRODUCTION 1 STUDY OBJECTIVES 2 II REVIEW OF LITERATURE 4 A. PROGRAMME EVALUATION 4 1. The Goal Attainment Model for Programme Evaluation 4 2. Outcome Measures and the Process of Care 4 3. The D i f f i c u l t i e s of Prospective Studies i n Health Care 5 4. Examplesof Programme Evaluation i n R e h a b i l i t a t i o n : 6 The Team Approach 5. C l i n i c a l Records as a Source of Data 7 6. The Tracer Concept 8 7. Programme Evaluation i n Workers' Compensation 8 B. MENISCECTOMY STUDIES 11 1. Return to Work 11 2. Long-Term E f f e c t s of Meniscectomy 12 3. The E f f e c t s of Meniscectomy on Occupation 14 4. Degenerative Changes i n the Knee Joint 14 5. Latency Period 15 6. Age at Time of Operation 16 7. Medial versus L a t e r a l Meniscectomy 16 8. Sex Factors 16 9. The E f f e c t s of Total versus P a r t i a l Meniscectomy 17 10. The E f f e c t s of Posterior I n c i s i o n 18 11, Unnecessary Meniscectomy 18 12. The Effectiveness of Postoperative R e h a b i l i t a t i o n 18 i n the Treatment of the Meniscectomy Patient 13, Implications of the L i t e r a t u r e on Meniscectomy for 20 the Present Study V C. A REVIEW OF THE LITERATURE ON THE EFFECTS OF COMPENSATION 2 0 ON DISABILITY 1. The D i s t i n c t i o n between Impairment and D i s a b i l i t y 21 2 . The Ef f e c t s of Compensation on the Recovery Process 2 1 3 . The Causes of Delayed Recovery 2 2 4 . The Workers' Compensation System 2 2 5 . Psychosocial Causes f o r Prolonged Recovery 2 3 6 . Malingering 2 6 7 . The Ef f e c t s of La b e l l i n g 2 6 8 . Secondary Gain 27 9 . Secondary Losses 2 7 1 0 . Physician/Patient Dynamics 27 1 1 . A S i t u a t i o n a l Explanation for Prolonged Recovery 2 9 APPLICATION OF THE LITERATURE TO THE PRESENT STUDY 2 9 III STUDY METHODOLOGY 3 0 A. POPULATION AND SAMPLE 3 0 B. DESIGN 3 3 1 . Approach to R e h a b i l i t a t i o n 3 3 2 . Time Intensity 3 3 3 . Factors Extraneous to Postoperative R e h a b i l i t a t i o n 3 6 4 . Cost and Benefits 3 6 C. INSTRUMENTATION AND DATA COLLECTION 3 6 1 . Return to Work 3 8 2 . Locale of R e h a b i l i t a t i o n 3 8 3 . Measurement of Degenerative Changes 4 0 4 . Preoperative R e h a b i l i t a t i o n 4 3 D. LIMITATIONS OF THE STUDY 4 4 1 . Threats to Internal V a l i d i t y 4 4 2 . The Ef f e c t s of Occupation and Income 4 4 3 . Latency 4 5 4 . Previous History 4 6 5 . Threats to External V a l i d i t y 4 6 v i Page E, ANALYSIS 47 FINDINGS OF THE STUDY 48 IV FINDINGS OF THE STUDY - PART 1: COMPARISON OF STUDY POPULATIONS 49 1. The Type of Postoperative R e h a b i l i t a t i o n 49 2. Age 50 3. Income 50 4. Degenerative Changes of the Knee Joint 50 5. Preoperative R e h a b i l i t a t i o n 54 6. Latency 57 1, Leg 57 8. Medial, L a t e r a l or B i l a t e r a l Meniscectomy 57 9, Complete or P a r t i a l Meniscectomy 60 10, Previous History of Injury of the Same Knee 60 11, Occupation 61 12, Posterior I n c i s i o n 61 13, Physician R e f e r r a l Patterns 61 14, Time Intensity of Postoperative R e h a b i l i t a t i o n Among 67 Community Patients SUMMARY 68 V FINDINGS OF THE STUDY, PART I I : ANALYSIS OF RETURN TO 69 WORK A. OVERVIEW 69 B. FACTORS AFFECTING RETURN TO WORK 73 1. The E f f e c t s of the Type of Postoperative R e h a b i l i t a t i o n , 73 Experience of Preoperative R e h a b i l i t a t i o n , Age, Meniscus Excised and Degenerative Changes on Return to Work Times 2. The Ef f e c t s of Income, Latency and Previous History of 79 the Knee 3. The E f f e c t of Posterior I n c i s i o n 79 4. The Ef f e c t s of Intensity of Postoperative R e h a b i l i t a t i o n 84 5. The E f f e c t s of Occupation 84 C. COSTS AND BENEFITS OF THE TYPES OF POSTOPERATIVE REHABILITATION 88 SUMMARY 90 v i i Page VI DISCUSSION OF STUDY FINDINGS 92 A. A BEHAVIOURAL FRAMEWORK FOR RETURN TO WORK 92 1. The Label "Disabled" 93 2. The Label "Claimant" 95 3. C e n t r a l i z a t i o n 95 4. Patients' Expectations 96 5. The Role of Physicians and R e h a b i l i t a t i o n Personnel 96 6. D i f f i c u l t i e s With the Behavioural Framework 97 B. CONSIDERATIONS OF STUDY FINDINGS WHICH FALL OUTSIDE 97 THE BEHAVIOURAL FRAMEWORK 1. Return to Work as the Only C r i t e r i o n of Outcome 97 2. Long-Term Results 99 3. Study Biases 100 4. G e n e r a l i z a b i l i t y of the Study Findings 101 C. REQUIREMENTS FOR FURTHER RESEARCH 102 1. The Need for a Medical Information System 102 2. The Need f or R e h a b i l i t a t i o n Research 103 3. The Need f or Compensation Research 103 CONCLUSIONS 104 BIBLIOGRAPHY 105 APPENDIX 111 v i i i LIST OF TABLES Table Page 2.1 Average Number of Weeks at Which the Pos meniscectomy 11 Patient Returns to Work, as Found i n the L i t e r a t u r e 2.2 The Long-Term E f f e c t s of Meniscectomy, as Found i n 13 the L i t e r a t u r e 3.1 Cases Excluded from the WCB Meniscectomy Study 34 3.2 Decisions on Mult i p l e Return to Work 39 3.3 C l a s s i f i c a t i o n of Type of Postoperative R e h a b i l i t a t i o n 41 of Patients with M u l t i p l e Locales of R e h a b i l i t a t i o n 4.1 Number of WCB Meniscectomy Patients by Type of Post- 49 operative R e h a b i l i t a t i o n : 1976 and 1977 4.2 Type of Preoperative R e h a b i l i t a t i o n by Type of Post- 55 operative R e h a b i l i t a t i o n Experienced by WCB Meniscectomy Cases: 1976 and 1977 4.3 Numbers and Percentages of WCB Meniscectomy Cases Who 60 Underwent Complete or P a r t i a l Meniscectomy: 1976 and 1977 4.4 Previous History of Injury to the Same Leg by Type of 62 Postoperative R e h a b i l i t a t i o n Experienced by WCB Meniscectomy Cases: 1976 and 1977 4.5 Postoperative R e h a b i l i t a t i o n R e f e r r a l Patterns of Surgeons 65 for Postoperative WCB Meniscectomy Cases: 1976 and 1977 4.6 Time Intensity of Postoperative R e h a b i l i t a t i o n for WCB 67 Meniscectomy Cases Treated i n the Community 5.1 Number of Days Before Return to Work by Type of Postoperative 69 Re h a b i l i t a t i o n Group, WCB Meniscectomy Cases: 1976 and 1977 5.2 Adjusted Summary of Measures of Return to Work by Type of 72 Postoperative R e h a b i l i t a t i o n , WCB Meniscectomy Cases: 1976 and 1977 5.3 Variations i n the Number of Days Return to Work Due to Type 74 of Postoperative R e h a b i l i t a t i o n , Age, Meniscus Excised and Degenerative Changes of the Knee, WCB Meniscectomy Cases: 1976 and 1977 5.4 Variations i n the Number of Days Return to Work Due to the 75 Type of Postoperative R e h a b i l i t a t i o n , Type of Preoperative R e h a b i l i t a t i o n , Age, and Degree of Degenerative Changes of the Knee, WCB Meniscectomy Cases: 1976 and 1977 IX Page 5.5 Mean Number of Days Return to Work by Type of Pre- 77 operative and Postoperative R e h a b i l i t a t i o n , WCB Meniscectomy Cases: 1976 and 1977 5.6 Mean Number of Days Return to Work by Type of Pre- 78 operative R e h a b i l i t a t i o n and Postoperative R e h a b i l i t a t i o n Non-sedentary Cases Only, WCB Meniscectomy Cases: 1976 and 1977 5.7 Variations i n the Number of Days Return to Work Due to 80 Type of Postoperative R e h a b i l i t a t i o n , Type of Preoperative R e h a b i l i t a t i o n and Age, for WCB Meniscectomy Cases With Non-sedentary Occupations and No Degenerative Changes of the Knee: 1976 and 1977 5.8 Variations i n the Number of Days Return to Work by Type of 81 Postoperative R e h a b i l i t a t i o n , Type of Preoperative R e h a b i l i -t a t i o n , Previous History of the Knee, Latency Period and Income Loss, WCB Meniscectomy Cases: 1976 and 1977 5.9 Variations i n the Number of Days Return to Work Due to 82 Type of Postoperative R e h a b i l i t a t i o n , Type of Preoperative R e h a b i l i t a t i o n , Previous History of the Knee, Latency Period and Income of WCB Meniscectomy Cases with Non-sedentary Occupations and No Degenerative Changes of the Knee: 1976 and 1977 5.10 Variations i n the Number of Days Return to Work Due to Type 83 of Postoperative R e h a b i l i t a t i o n , Type of Preoperative R e h a b i l i t a t i o n and Presence of Poste r i o r I n c i s i o n , WCB Meniscectomy Cases: 1976 and 1977 5.11 Variations i n the Number of Days Return to Work Due to the 85 Type of Postoperative R e h a b i l i t a t i o n , Type of Preoperative R e h a b i l i t a t i o n , and Presence of Poste r i o r I n c i s i o n for those WCB Meniscectomy Cases With Non-sedentary Occupations and No Degenerative Changes of the Knee: 1976 and 1977 5.12 Variations i n the Number of Days Return to Work Due to the 86 Ef f e c t s of Preoperative R e h a b i l i t a t i o n and the Intensity of Postoperative R e h a b i l i t a t i o n , for WCB Meniscectomy Cases Receiving Postoperative R e h a b i l i t a t i o n i n the Community: 1976 and 1977 5.13 Variations i n the Number of Days Return to Work Due to the 87 Type of Postoperative R e h a b i l i t a t i o n , Type of Preoperative R e h a b i l i t a t i o n and Occupation, WCB Meniscectomy Cases: 1976 and 1977 5.14 The Number of Treatments Per R e h a b i l i t a t i o n Category and 89 Costs, WCB Meniscectomy Cases: 1976 and 1977 X LIST OF FIGURES Figure Page 3.1 Design Model for the Evaluation of R e h a b i l i t a t i o n Outcomes 37 of WCB Meniscectomy Cases 4.1 Age D i s t r i b u t i o n of Postoperative R e h a b i l i t a t i o n Populations: 51 WCB Meniscectomy Cases, 1976 and 1977 4.2 Income Loss D i s t r i b u t i o n of Postoperative R e h a b i l i t a t i o n 52 Populations, WCB Meniscectomy Cases: 1976 and 1977 4.3 D i s t r i b u t i o n of Postoperative R e h a b i l i t a t i o n Populations by 53 : Degree of Degenerative Changes, WCB Meniscectomy Cases: 1976 and 1977 4.4 D i s t r i b u t i o n of Preoperative R e h a b i l i t a t i o n Within Types 56 of Postoperative R e h a b i l i t a t i o n Groups, WCB Meniscectomy Cases: 1976 and 1977 4.5 Latency D i s t r i b u t i o n of Postoperative R e h a b i l i t a t i o n Populations 58 WCB Meniscectomy Cases: 1976 and 1977 4.6 D i s t r i b u t i o n of Population of Postoperative R e h a b i l i t a t i o n 59 Groups by Type of Meniscus Removed: WCB Meniscectomy Cases, 1976 and 1977 4.7 D i s t r i b u t i o n of Postoperative R e h a b i l i t a t i o n Populations by 63 Previous History of the Same Leg, WCB Meniscectomy Cases: 1976 and 1977 4.8 D i s t r i b u t i o n of Study Population by Presence of Posterior 64 Inc i s i o n s : WCB Meniscectomy Cases, 1976 and 1977 5.1 Comparison of Return to Work Postmeniscectomy of WCB C l i n i c , 70 Community, and No Physical Therapy Patients: 1976 and 1977 5.2 Comparison of Cumulative Frequencies for Return to Work 71 Postmeniscectomy of WCB C l i n i c , Community, and No P h y s i c a l Therapy Patients, WCB Meniscectomy Cases: 1976 and 1977 6.1 Modelling the Pathway to D i s a b i l i t y (adapted from Koshel & 94 Granger 1978) x i ACKNOWLEDGEMENTS I The author g r a t e f u l l y acknowledges the c r i t i c i s m , assistance and support of many persons and organizations. The Workers' Compensation Board of B r i t i s h Columbia has been outstanding i n the support i t has given t h i s p r o j e c t . In p a r t i c u l a r , I would l i k e to thank Dr. Adam L i t t l e , Chairman of the WCB, whose enthusiastic reception of the i n i t i a l proposal encouraged the evolution of t h i s t h e s i s . Many, many thanks are owing to Dr. CM. Robertson, former Medical O f f i c e r of the WCB, who supervised the research and provided invaluable advice on project design and development. Special mention must be made of the cooperation and genuine i n t e r e s t I received from my committee. Thank you to Dr. David Bates, Dr. Mort Warner, and Don Earner, of the Department of Health Care and Epidemiology, Faculty of Medicine, U.B.C, and Dr. Ralph E. Outerbridge, D i v i s i o n of Orthopedics, Department of Surgery, Faculty of Medicine, U.B.C. Dr. Anne Crichton and Dr. Annette Stark, of the Department of Health Care and Epidemiology, U.B.C, provided constructive c r i t i c i s m of the i n i t i a l p roject. S t a t i s t i c a l assistance was received from Dr. Ned Gl i c k , Department of Health Care and Epidemiology, U.B.C, and Keith Mason, S t a t i s t i c a l Services Coordinator, W.CB. Stan K i t a , of the U.B.C. Computing Centre, and Gordon Muir, of the D i v i s i o n of Health Services Research and Development, U.B.C, helped me overcome my fear of computers. Many thanks to Shelley Smits and Marie McKenzie of the WCB medical steno pool, and to Fred Vickman, Staff A r t i s t . H e lpful suggestions were received from Marilyn Atkins, Elaine H a r r i s , and Barbara Taylor, who are physiotherapists with whom I have shared a working r e l a t i o n s h i p . F i n a n c i a l assistance was provided by the W.CB. , and a National Health Student Fellowship, Health & Welfare Canada. F i n a l l y , I would l i k e to thank my cousin, Dr. Stan Shapson, and my parents, whose long-distance encouragement gave me the impetus to f i n i s h the p roject. And many, many thanks go to Peter Meurrens for h i s patience i n seeing me through the f i n a l traumas. -1-CHAPTER I INTRODUCTION The Workers' Compensation Board of B r i t i s h Columbia (WCB), established i n 1917, provides support for working people against the hazards of employment. Through a comprehensive approach, i t i s responsible for prevention, adjudication of claims and income maintenance, and medical a i d . The WCB's approach to physi c a l r e h a b i l i t a t i o n * i s highly c e n t r a l i z e d . The L e s l i e R. Peterson R e h a b i l i t a t i o n Center (commonly r e f e r r e d to as the "WCB C l i n i c " ) i n Richmond, B r i t i s h Columbia, o f f e r s a m u l t i d i s c i p l i n a r y programmeof ph y s i c a l therapy, remedial therapy, occupational therapy, and i n d u s t r i a l therapy, with a d d i t i o n a l s p e c i a l i s t support s t a f f , such as psychologists, where necessary. The programme i s highly time intensive. No evaluation of the programme's e f f i c i e n c y or effectiveness i n terms of outcomes has been conducted. The m u l t i d i s c i p l i n a r y , time-^intensive .programme of the WCB C l i n i c i s comparable to that of r e h a b i l i t a t i o n centres which treat major impairments such as s p i n a l cord i n j u r i e s , amputations, or rheumatoid a r t h r i t i s . However, t h i s approach i s not usual i n the treatment of sprains and s t r a i n s , and most e l e c t i v e orthopedic s u r g i c a l procedures. When noncompensable, such conditions are usually treated i n the community by the attending physician and a physiotherapist, i f indicated. Physiotherapy i n most cases i s rendered two or three times per week, rather than d a i l y as i n the WCB C l i n i c . In 1976, there were 4300 admissions to the WCB C l i n i c . Although the t o t a l number of claims increased i n that year, admissions to the C l i n i c were twelve percent lower than i n 1975 because of increased u t i l i z a t i o n of h o s p i t a l physiotherapy departments and priv a t e physiotherapy c l i n i c s . ( S i x t i e t h Annual Report, WCB, 1976.) Based upon t h i s information, a r e t r o -spective comparison of outcomes measured by the number of days before return to work of the WCB patient treated at the C l i n i c , as compared to the WCB patient treated at these other f a c i l i t i e s was proposed. The study model was then expanded to include a comparison of outcomes between these patients and those WCB cases who did not receive physiotherapy postoperatively. * Throughout t h i s document, unless otherwise s p e c i f i e d , the term " r e h a b i l i t a t i o n " refers to ph y s i c a l r e h a b i l i t a t i o n . -2-Return to work was chosen as an evaluation of outcome because i t i s I measurable r e t r o s p e c t i v e l y , and i s recorded i n the claim f i l e s as the termination of wage loss b e n e f i t s . It i s r e a l i z e d , however, that return to work i s not n e c e s s a r i l y a true return to the work place, but rather a termination of wage loss benefits by the WCB because of the worker's presumed a b i l i t y to resume employment. Because return to work i s the terminology used by the WCB, the study uses t h i s term. In order to study return to work times, the patients compared must be as s i m i l a r as p o s s i b l e . Although the majority of the cases treated at the C l i n i c are sprains and s t r a i n s , i t was decided that these were not the most s u i t a b l e vehicles of study because there i s vagueness i n the diagnosis of sprains and s t r a i n s , and because there i s no d i r e c t v i s u a l i z a t i o n of the structures involved. Thus, c l a s s i f i c a t i o n of these i n j u r i e s r e t r o s p e c t i v e l y to provide for equivalency of control groups i s d i f f i c u l t . It i s believed that postoperative meniscectomy* patients provide a r e a l i s t i c vehicle of study because: 1) Diagnostic aids, such as x-ray, arthrogram, and arthroscopy, when performed, provide reasonable d e s c r i p t i o n of bony structures and s o f t tissues around the knee; 2) The i n t e r n a l structures of the knee j o i n t are usually well v i s u a l i z e d during the operative procedure. These c h a r a c t e r i s t i c s permit more accurate c l a s s i f i c a t i o n of pathology i n order to c o n t r o l for confounding v a r i a b l e s ; 3) The operative procedure i s t e c h n i c a l l y less complex than many other s u r g i c a l procedures; 4) Although r e h a b i l i t a t i o n routines may vary according to the treatment philosophies of the attending physician and physiotherapist, the researcher, through work experience, has noted that procedures for the r e h a b i l i t a t i o n of the meniscectomy patient tend to be more standard than treatment procedures for sprains and s t r a i n s ; 5) In 1976, the WCB paid for 565 meniscectomies, making meniscectomy the most frequent s u r g i c a l procedure for which payment was made to orthopedic surgeons. STUDY OBJECTIVES The objectives of t h i s research project are as follows: 1) To determine i f the three d i f f e r e n t approaches to r e h a b i l i t a t i o n are r e l a t e d to the differences i n the times of return to work of the post-operative meniscectomy patient. * Meniscectomy i s a s u r g i c a l procedure by which a damaged c a r t i l a g e i s removed from the knee j o i n t . -3-2 ) To determine i f a highly time-intensive approach to the rehabilitation of the postoperative meniscectomy patient in the community is effective. 3) To identify those factors extraneous to postoperative rehabilitation (such as age, latency period, osteoarthritis) which most strongly affect return to work for the postoperative WCB meniscectomy patient. 4) To determine the cost and benefits of the different approaches to the rehabilitation of the WCB postoperative meniscectomy patient. -4-CHAPTER II REVIEW OF LITERATURE A review of the l i t e r a t u r e was conducted i n the following areas: A. Programme Evaluation; B. Meniscectomy Studies, and C. The E f f e c t s of Compensation. A. PROGRAMME EVALUATION Programme evaluation i s a r e l a t i v e l y recent phenomenon. Interest i n programme evaluation within health care r e s u l t s from the concerns of professionals within the f i e l d , about programme eff e c t i v e n e s s , as well as pressures from governments and the p u b l i c . (Schulberg et a l , 1967, pp.3.) Because of the e s c a l a t i o n of health care costs, a c c o u n t a b i l i t y to funding agencies Is a strong motivation for programme evaluation. (Breckenridge 1978.) 1. The Goal Attainment Model for Programme Evaluation In the goal attainment model the goals of the agency are i d e n t i f i e d , and i t s effectiveness i n reaching i t s goals i s evaluated. However, many organizations are unsure of t h e i r goals, and thus goal i d e n t i f i c a t i o n may be d i f f i c u l t . (Steers 1977 pp.19.) Programme objectives must be evaluated at a l e v e l which i s both measurable and relevant. Therefore, programme success i n reaching p r a c t i c a l objectives rather than i d e a l , global goals should be evaluated. (Schulberg et a l , 1967, pp.7.) In determining the effectiveness of agency programmes, the i n v e s t i g a t o r must be mindful of what c r i t e r i a the agency i t s e l f uses i n measuring performance. (Goldberg 1974.) 2. Outcome Measures and the Process of Care Donabedian (1966) suggests outcome as a c r i t e r i o n of q u a l i t y i n evaluating medical care, because outcome i s usually concrete. However, he warns that many factors other than medical care may influence outcomes. Thus, precaution must be taken to hold a l l s i g n i f i c a n t factors other than medical care constant i f v a l i d conclusions are to be drawn. Nichols (1976) examines the appropriateness of using c l i n i c a l outcome measures i n the evaluation of the effectiveness of r e h a b i l i t a t i o n . -5-The two extremes of c l i n i c a l and f u n c t i o n a l outcome measures are death, which i s "hard" objective data, and the patient's attitudes and s a t i s f a c t i o n s , which are " s o f t " subjective measures. Nichols suggests that many of the problems of assuring the effectiveness of r e h a b i l i t a t i o n could be resolved i f r e h a b i l i t a t i o n i s regarded as p r i m a r i l y a behavioural process with aims which are predominantly f u n c t i o n a l , s o c i a l , and economic. In t h i s way, r e h a b i l i t a t i o n can be separated from the purely c l i n i c a l aspects of medical treatment i n which the aims are p r i m a r i l y pathophysiological. Nichols regards r e h a b i l i t a t i o n medicine as being p a r t i c u l a r l y concerned with the behavioural aspects of recovery from any i l l n e s s or i n j u r y i n response to deformity. However, he does stress that for d i s a b i l i t i e s which are of a temporary nature, such as fractures, outcome measures based s p e c i f i c a l l y upon the pathological process involved must be used. Another evaluation approach described by Donabedian i s the examination of the process of care. Kessner et a l (1973) warn that the strengths and weaknesses of process cannot be i d e n t i f i e d without knowing outcome, but they add that the outcome alone may be misleading i f the patient receives unnecessary diagnostic tests or inappropriate therapy, 3. The D i f f i c u l t i e s of Prospective Studies i n Health Care Meade (1977) l i s t s the following main d i f f i c u l t i e s i n the prospective study of the c l i n i c a l and s o c i a l effectiveness of r e h a b i l i t a t i o n models: i ) Randomized co n t r o l l e d studies are usually inappropriate or unfeasible i n r e h a b i l i t a t i o n , i i ) Measuring outcome i s usually d i f f i c u l t . "Quality of l i f e " and "function" are s o f t , subjective measures, i i i ) Large numbers of cases are often not a v a i l a b l e , iv) Often, too much information i s c o l l e c t e d . The researcher engages upon a " f i s h i n g expedition" but the relevance of much of the data i s uncertain. v) "Blindness" i n studies i s generally not possible as both the patients and the investigators usually know which treatment i s being applied. v i ) There are e t h i c a l considerations. Doctors and therapists are often convinced that one treatment i s better than the other. They f i n d i t d i f f i c u l t to allow t h e i r patients to p a r t i c i p a t e i n a programme which c o n f l i c t s with t h e i r treatment philosophies. v i i ) F i n a l l y , there are other considerations. Meade stresses that r e h a b i l i t a t i o n t r i a l s are i n e f f e c t questioning several time-honoured -6-treatments i n which therapists have been trained, and which are generally assumed to be e f f e c t i v e . This i s a p o t e n t i a l l y anxiety-producing s i t u a t i o n although, i f r e a l i z e d and managed as such, i t can be turned into an i n q u i r i n g approach to r e h a b i l i t a t i o n that i s e s s e n t i a l f or in c r e a s i n g l y e f f e c t i v e management of disabled patients. 4. Examples of Programme Evaluation i n R e h a b i l i t a t i o n : The Team Approach One time-honoured approach which i s being examined i s team care i n r e h a b i l i t a t i o n . Team care i n r e h a b i l i t a t i o n i s almost a unanimously endorsed proposition. A review of the l i t e r a t u r e reveals that most published accounts of team care are p r e s c r i p t i v e or d e s c r i p t i v e , but there i s very l i t t l e empirical research into i t s e f f e c t i v e n e s s . Effectiveness i s often assumed on f a i t h . (Halstead 1976), A few evaluators have studied team care using d i f f e r e n t design models. Denistan and Rosenstock (1973) agree with Meade that i t i s often impossible to use a randomized control group. As an example of a quasi-experimental design model, they c i t e the Michigan A r t h r i t i s Control Programme, i n which the researchers had p a r t i a l but not complete co n t r o l over the s i t u a t i o n . The Michigan A r t h r i t i s Control study used non-equivalent c o n t r o l groups i n which the assignment of treatment and control conditions are not random, but rather the groups are natural c o l l e c t i v i t i e s deemed but not proven to be s i m i l a r . The r e s u l t s of the study showed that comprehensive treatment, involving the occupational t h e r a p i s t , physiotherapist, s o c i a l worker, and v i s i t i n g nurse, was more e f f e c t i v e than conventional care i n the treatment of rheumatoid a r t h r i t i s . Conventional care was whatever treatment was a v a i l a b l e i n the community. Katz et a l (1962) also used natural c l u s t e r s of patients to evaluate the effectiveness of comprehensive treatment i n the r e h a b i l i t a t i o n of fractures of the hip i n the aged. Outcomes for those patients who were admitted to hospitals with intensive r e h a b i l i t a t i o n approaches were compared to outcomes for those patients who experienced no a d d i t i o n a l r e h a b i l i t a t i o n but were rather discharged home for convalescence. The non-rehabilitated group showed more d e t e r i o r a t i o n i n ambulation and more severe d e t e r i o r a t i o n i n a c t i v i t i e s of d a i l y l i v i n g than the r e h a b i l i t a t e d group. Random co n t r o l l e d experimental design models were used i n two studies evaluating the effectiveness of team care. In one study (Katz et a l 1968), patients with rheumatoid a r t h r i t i s were randomly assigned to treatment and -7-c o n t r o l groups to determine the effectiveness of m u l t i d i s c i p l i n a r y care i n both the c l i n i c and the home. The controls received the usual treatment a v a i l a b l e i n the community. It was found that those patients receiving comprehensive care i n the c l i n i c and at home had fewer deteriorations i n a c t i v i t i e s of d a i l y l i v i n g , more improvements i n economic independence, and more improvements c l i n i c a l l y , than those patients receiving conventional care. However, i n one study, team care was not found to be more e f f e c t i v e i n the treatment of stroke victims (Feldman et a l 1962). In a c o n t r o l l e d study of an unselected group of stroke patients who were randomly divided into two groups, the group receiving f u n c t i o n a l l y oriented medical care (the control group) did as well as the group who received a formal comprehensive r e h a b i l i t a t i o n program. The c o n t r o l group a c t u a l l y had less p h y s i c a l impairment on followup one year l a t e r than the r e h a b i l i t a t e d group. However, the r e h a b i l i t a t e d group had s l i g h t l y better f u n c t i o n a l capacity. This fi n d i n g contradicts an e a r l i e r study on stroke, which found that formal r e h a b i l i t a t i o n resulted i n greater recovery of muscle function (Benton et a l 1951). What can be learned from these studies? The most important message i s that the evaluation of r e h a b i l i t a t i o n programmes i s po s s i b l e . Research ethics may constrain design models based upon randomness or neglect of treatment, but studies using natural c o l l e c t i v i t i e s are d e f i n i t e l y possible. The above studies are not conclusive v e r d i c t s on the effectiveness of teamwork, but rather they r e f e r to teamwork i n s p e c i f i c cases. These findings cannot be generalized to meniscectomies. Rheumatoid a r t h r i t i s and stroke are complex pathologies while a torn meniscus usually occurs i n only one j o i n t . However, Sommerville (1970) and Ford (1974) believe that early and intensive r e h a b i l i t a t i o n i s as necessary following simple i n j u r i e s , such as fractures,as i n the more involved d i s a b i l i t i e s . Katz's study (1962) confirmed t h i s for hip fractures i n the e l d e r l y . The study population i n meniscectomy i s usually much younger. 5. C l i n i c a l Records as a Source of Data Retrospective studies are dependent upon records. C l i n i c a l records are usually considered a valuable source of information for assessing q u a l i t y of care, but Donabedian (1966) cautions that inaccuracies may a r i s e because of a v a i l a b i l i t y , adequacy, v e r a c i t y , or completeness. Fessel and Van Brunt -8-(1972) warn that medical records are often of l i m i t e d use for examining the processes of care rather than outcomes because of the s u b j e c t i v i t y of the examiner and inadequacies i n recording. 6. The Tracer Concept Kessner et a l (1973) recommend programme evaluation using " t r a c e r s " . A set of s p e c i f i c health problems can serve as tracers i n analyzing health care d e l i v e r y because the way i n which an i n s t i t u t i o n r o u t i n e l y administers care for common ailments indicates the general q u a l i t y of care and the e f f i c a c y of the i n s t i t u t i o n d e l i v e r i n g that care. The tracers required are d i s c r e t e , i d e n t i f i a b l e health problems. Tracers are selected according to s i x c r i t e r i a : i ) A tracer should have a d e f i n i t e f unctional impact. It should be a condition that i s l i k e l y to be treated and which causes s i g n i f i c a n t f u nctional impairment. i i ) A tracer should be r e l a t i v e l y w e ll defined and easy to diagnose, i i i ) Prevalence should be high enough to permit the c o l l e c t i o n of adequate data from a l i m i t e d population sample. iv) The natural h i s t o r y of the condition should vary with u t i l i z a t i o n and effectiveness of medical care. The conditions under study should be s e n s i t i v e to the q u a l i t y or quantity (or both) of the services received by the patient. v) The techniques of medical management of the condition should be well defined for at l e a s t one of the following processes: prevention, diagnosis, treatment or r e h a b i l i t a t i o n . v i ) The e f f e c t s of non-medical factors on the tracer should be understood (for example, s o c i a l , c u l t u r a l and economic e f f e c t s ) . As a trac e r , meniscectomy f i t s these c r i t e r i a . 7. Programme Evaluation i n Workers' Compensation To determine i f the r e s u l t s of treatment of problem "low back" patients i n the Ontario Workmen's Compensation Board Hospital and R e h a b i l i t a t i o n Centre j u s t i f i e d the time, e f f o r t and expense involved, White (1966) evaluated outcomes for 194 "problem" back patients. "Problem backs" were defined as those cases who were disabled longer than s i x weeks. The cases were divided into two groups. In Group A, the patient was discharged from the Centre to the treatment of h i s personal physician, while those patients -9-i n Group B were treated at the Centre for s i x weeks on a graduated treatment program (unless the patient returned to work e a r l i e r than s i x weeks). The groups were judged comparable according to various demographic charac-t e r i s t i c s , diagnosis, and se v e r i t y of symptoms. The measurement of the effectiveness of treatment was based on the assessment of the actual accomplishment at work during the f i r s t three months a f t e r discharge from the study. The range of accomplishment was from not working at a l l to working f u l l time at f u l l duties, with various combinations of part-time work and modified work duties i n between. The group treated at the Centre had 42.4% s a t i s f a c t o r y r e s u l t s i n returning to work as compared to only 15.8% s a t i s f a c t o r y r e s u l t s i n the group discharged to the treatment of the personal physician. White remarks disappointedly that s a t i s f a c t o r y r e s u l t s were obtained i n only four of every ten patients treated at the Centre. Prolonging t r e a t -ment beyond s i x weeks yie l d e d only nine a d d i t i o n a l s a t i s f a c t o r y r e s u l t s i n fo r t y patients. Therefore, although the rate of successful treatment was more than two-and-a-half times higher among those who were treated i n the Centre than among those who were referred back to the community, continuing treatment at the Centre longer than s i x weeks was r e l a t i v e l y unrewarding. Indeed, White suggests that the continuation of any type of treatment, the r e s u l t s of which are unsatisfactory, can have a detrimental e f f e c t because i t may r e s u l t i n pessimism and lower morale on the part of the patient. Milbrandt (1973) concurs that, unless there i s good i n d i c a t i o n , treatment of low back s t r a i n at a r e h a b i l i t a t i o n c l i n i c for longer than s i x to eight weeks i s r e l a t i v e l y unrewarding and may even be harmful by destroying morale. The study conducted by White was part of a larger evaluation of 770 patients. Of the patients treated at the Centre, he found no s i g n i f i c a n t difference i n outcomes due to the type of therapy or the i n t e n s i t y of therapy. It was attendance at the Centre i t s e l f that was judged to be s i g n i f i c a n t . White thus wonders i f p h y s i c a l therapy per se has any b e n e f i c i a l e f f e c t . I t i s important to note that White studied patients previously i d e n t i f i e d as problem cases. The r e h a b i l i t a t i o n system he examined i s s i m i l a r to the one i n B r i t i s h Columbia, but the present study i s examining a l l postoperative meniscectomy cases, Robertson (1977) suggests the need for a s p e c i a l study to obtain u s e f u l comparative data about back-injured patients attending the WCB C l i n i c or other f a c i l i t i e s . He notes that back claimants who attended the C l i n i c appeared to be prolonged time loss cases, and suggests that t h i s may be due -10-to complicating pathologies, compensable or non-compensable, Because of the vagueness i n the diagnosis of back i n j u r i e s and because meniscectomies more c l o s e l y approximate the " t r a c e r " conditions of Ressner et a l , the researcher decided to use meniscectomy to obtain comparative data. It i s f e l t that a back study would be more sui t a b l e as a prospective study where more accurate c l a s s i f i c a t i o n of pathology could be c o n t r o l l e d . -11-B. MENISCECTOMY STUDIES To use a tracer i n program evaluation, the fu n c t i o n a l impact of the tracer and the variables which a f f e c t i t s outcome must be understood. A l i t e r a t u r e review on meniscectomy was conducted so that a l l relevant variables which can influence outcomes would be i d e n t i f i e d and incorporated into the study. 1. Return to Work Table 2.1 shows the average number of weeks that investigators have found to be the time at which the postmeniscectomy patient usually returns to work. The averages range from four^-and-a-half to twelve weeks; however most of the studies indicate return to work times of under eight weeks postoperative, Table 2.1 Average Number of Weeks at Which the Postmeniscectomy  Patient Returns to Work, as Found i n the L i t e r a t u r e NAME OF INVESTIGATOR AVERAGE NUMBER OF WEEKS RETURN TO WORK TARGET POPULATION Wynn Parry et a l (1958) Gough (1975) Leonard (1975) Seymour (1969) Karumo (1977) Helfet (1974, pp.161) 8 or 9 * 6.5 to 7.5 ** 7.5 ** 4.5 ** 6.5 ** 10 ** 6 *** 6 to 8 *** Servicemen 76% heavy workers Mixed occupational groups Sedentary workers Manual workers 50% blue c o l l a r workers 50% receiving compensation F i t athletes The middle-aged S m i l l i e (1978, pp.173) 12 *** Coalminers Return to work for 74% of the cases studied Average return to work for a l l cases studied Suggested return to work based upon experience -12-Wynn Parry et a l (1958) observed that 8.9 percent of the patients were discharged back to m i l i t a r y duty with e f f u s i o n s . * They believe that i f the patient has excellent quadriceps** and sound ligaments, and i f there i s an absence of any evidence of pathology i n the knee, the p e r s i s -tence of a mild e f f u s i o n should not prevent return to work. Of 120 servicement which Helfet (1974, pp.161) studied, 85.8 percent were c l a s s i f i e d as A - l within an average of nine weeks postmeniscectomy. ("A-l" indicates an a b i l i t y to do a physical-assault course, a three-mile cross-country run, and a f i f t e e n - m i l e route march). S m i l l i e (1978, pp.173), however, believes that a degree of p h y s i c a l f i t n e s s which w i l l withstand a t h l e t i c a c t i v i t i e s or hard labour i s r a r e l y possible i n less than twelve weeks. His observation on the rate of recovery of coalminers receiving continuity of physiotherapy i n both h o s p i t a l and r e h a b i l i t a t i o n centre show that the musculature of the injured j o i n t only reaches a stage of development comparable with the normal i n approximately the same twelve-week period. 2. Long-Term E f f e c t s of Meniscectomy Many inve s t i g a t o r s have studied the long-term e f f e c t s of meniscectomy. The percentage of s a t i s f a c t o r y r e s u l t s d i f f e r often because the d e f i n i t i o n of success varies from study to study. A serious problem i n most of these studies i s that long-term follow-up depends upon response to questionnaires sent out to patients. There i s thus much s e l f - s e l e c t i o n bias i n these studies. Table 2.2 gives a summary of the long-term e f f e c t s of meniscectomy which have been indicated by various researchers. * E f f u s i o n i s defined as the escape of f l u i d into the knee (commonly ref e r r e d to as "swelling".) ** The quadriceps i s the large muscle on the front of the thigh. Table 2,2 The Long-Term E f f e c t s of Meniscectomy, as Found i n the L i t e r a t u r e .Name of Investigator Perey (1962) Huckle (1965) Gear (1967) Tapper and Hoover (1969) Response Rate* 50% 30% 27% 70% Number of Knees Studied 33 134 70 64 50 Appel (1970) 97% 223 113 100 490 Johnson et a l (1974) Noble (1975) 49% 92% 99 140 113 27 Duffin (1977) 75% 65 Number of Years Postoperative 30 12-20 •10 or more 10-30 5-45 5-37 1-11 1.5+ Method of Examination Questionnaire 70% e x c e l l e n t , 15% good i n regard to the a b i l i t y to do hard work and sports C l i n i c a l 26% normal, 50% s a t i s f a c t o r y * * Questionnaire 40% normal, 64% s a t i s f a c t o r y * * C l i n i c a l and 36% s t i l l had symptoms questionnaire C l i n i c a l Questionnaire C l i n i c a l C l i n i c a l C l i n i c a l Questionnaire C l i n i c a l and Questionnaire Both groups o v e r a l l : 38% normal 30% excellent or good (some symptomatology, no impairment of a c t i v i t y ) , 19% f a i r (minimal impairment), 13.3% poor. Subjective: 62.3% no complaints, 29.1% mild complaints, 7.5% d i s t i n c t complaints, 1.1% f a i r l y pronounced complaints. Objective: 80.2% normal or a si n g l e minor f i n d i n g , 19.8% with more than one minor f i n d i n g , or with one pronounced f i n d i n g . 42.5% s a t i s f a c t o r y , 57.5% unsa t i s f a c t o r y * * * Both groups o v e r a l l : l e s s than 50% painfree, 16% complained of s t i f f n e s s , 16% i n s t a b i l i t y , 56% j o i n t l i n e tenderness, 20% wasting, j o i n t l i n e tenderness and l i m i t a t i o n of movement. 24% normal. 40% unable to return to sport 82% of 40 cases showed some loss of function (measured by a b i l i t y to do r o t a t i o n a l squat jumps). * Percent from t o t a l sample responding ** Normal symptom-free, or showing mild pain or s t i f f n e s s but without swelling, locking or giving way *** Based upon lowest r a t i n g assigned to any of ten c r i t e r i a : a c t i v i t y l e v e l , pain on a c t i v i t y , pain with r e i n j u r y , e f f u s i o n , g i v i n g way, locking, a b i l i t y to walk s t a i r s , a b i l i t y to walk on rough ground, a b i l i t y to squat, a b i l i t y to return to sports. 3. The E f f e c t s of Meniscectomy on Occupation -14-Most of the occupations of the cases evaluated by Tapper and Hoover (1969) to determine the long-term e f f e c t s of meniscectomy, required d a i l y p h y s i c a l exertion. They concluded therefore, that meniscectomy does not preclude a man's engaging i n a p h y s i c a l occupation over a long span of time. Want (1978), however, noted from personal observation that the majority of coalminers i n the area where he practices are s t i l l doing l i g h t work i n the p i t s two years a f t e r meniscectomy due to an i n a b i l i t y to crawl or squat for long periods. Appel (1970) concluded that the type of occupation a f t e r meniscectomy was of no importance for the l a t e r e s u l t . 4. Degenerative Changes i n the Knee Joi n t It i s generally believed that the presence of any l e s i o n at operation other than a torn meniscus predisposes the j o i n t to a greater l i k e l i h o o d of a poor ultimate outcome (Johnson, et a l , 1974). Appel (1970) found that roentgenologic o s t e o a r t h r i t i s * p r i o r to operation gave r i s e to increased frequency of unsatisfactory r e s u l t s i n the long run. Charnley, however, (i n Johnson, et a l , 1974) found no difference i n the r e s u l t s for patients with such lesions as minor ligament s t r a i n , early a r t h r i t i s , and chondro-malacia** than for those patients having meniscal lesions only. Johnson et a l found t h e i r data i n agreement with Charnley, with the exception of early a r t h r i t i s . O'Donoghue (1956) surveyed c l i n i c a l l y 350 operative cases diagnosed as i n t r i n s i c conditions of the knee. These included other cases i n addition to lesions of the meniscus. S i x t y - f i v e percent of a l l cases showed some d i s c e r n i b l e degree of p a t e l l a r * * * malacia, according to h i s d e f i n i t i o n of the pathology. F i f t e e n percent had very severe involvement with "crabmeat" c a r t i l a g e , denuded bone, and c r a t e r s . As the degree of malacia increased, O'Donoghue noted that the q u a l i t y of the r e s u l t s deteriorated. As episodes of preoperative locking increased, there was found to be an increase i n the degree of p a t e l l a r m a l a c i a . However, one-t h i r d of the cases which never locked s t i l l showed malacia. O'Donoghue * O s t e o a r t h r i t i s i s defined as degenerative j o i n t disease. ** Chondromalacia i s defined as abnormal softening of c a r t i l a g e . *** The p a t e l l a i s commonly known as the "kneecap". -15-noted that there i s a great deal of v a r i a t i o n i n reporting the incidence of chondromalacia p a t e l l a e during knee arthrotomies* according to the degree of pathology that the surgeon in t e r p r e t s as 'malacia'. However, whatever c l a s s i f i c a t i o n i s used, he believes that the percentage i s much higher than had been generally accepted. In a study of 196 cases of medial meniscectomy, Outerbridge (1961) found that 51.5% showed evidence of abnormal a r t i c u l a r c a r t i l a g e of the p a t e l l a at time of operation. A r e l a t i o n s h i p between the time and the sev e r i t y of the i n j u r y causing the tear of the meniscus and the chondro-malacia of the p a t e l l a was not found. Worrel (1973) found that 51% of 54 postmeniscectomy knees examined displayed c l i n i c a l evidence of chondromalacia of the p a t e l l a as compared to 6.5% of 46 non-operated knees of the same group of p a t i e n t s . (Four patients had undergone meniscectomies on both knees and thus did not have a non-surgical knee av a i l a b l e for comparison). Sixteen percent of the knees of a random sample of 50 patients who had never experienced i n j u r y or surgery displayed c l i n i c a l evidence of chondromalacia of the p a t e l l a . Worrel wonders i f the performance of a meniscectomy, or some aspects of postmeniscectomy care, accelerate p r e - e x i s t i n g degenerative changes i n the c a r t i l a g e of the p a t e l l a , or i f the meniscectomy i n i t i a t e s these changes. 5. Latency Period The latency period i s the time elapsed between i n j u r y and operation. Wynn Parry, et a l (1958) reported a higher frequency of o s t e o a r t h r i t i s i n patients who had experienced a longer latency period. However, the length of time symptoms had been present before operation had no e f f e c t on the treatment time. Tapper and Hoover (1969) found no connection between a long latency period and o s t e o a r t h r i t i s . The duration of symptoms pre-operatively was found to have no bearing on the o v e r a l l long-term e f f e c t s of meniscectomy. A longer latency period was not found to c o r r e l a t e with worse r e s u l t s i n Appel's study (1970). Gear (1967) suggests that the length of h i s t o r y before operation i s one of the factors responsible for poor r e s u l t s ten years postoperative. Patients with r a d i o l o g i c a l changes were found to have had an average latency period of 20 months, while those with normal An arthrotomy i s an i n c i s i o n into a j o i n t . -16-knees had an average h i s t o r y of only nine months latency. Johnson, et a l (1974) found that the longer the duration of symptoms and the greater the frequencies of re i n j u r y before meniscectomy, the worse the f i n a l r e s u l t s . 6. Age at Time of Operation Appel (1970) and Johnson, et a l (1974) determined that age at the time of operation did not influence the long-term r e s u l t s of meniscectomy. In the l a t t e r study, patients under 21 years of age had fewer excellent r e s u l t s than those over 21, but the difference was not s i g n i f i c a n t . Tapper and Hoover (1969) also reported that patients who were 20 years old or less at the time of operation had fewer excellent or good r e s u l t s than those 21 or over. They believe that the explanation for t h i s r e s u l t l i e s i n the more v i o l e n t nature of injury i n the younger patients and the p o s s i b i l i t y of continued a t h l e t i c abuse. (Appel, however, found that trauma as an e t i o l o g i c a l factor f or the rupture of the meniscus, as compared to a rupture caused by a degenerative process, did not influence r e s u l t s . ) 7. Medial Versus L a t e r a l Meniscectomy Johnson, et a l (1974) reported better r e s u l t s a f t e r medial meniscectomy than l a t e r a l . Knees with e i t h e r medial or l a t e r a l meniscectomy had better recovery than those with both menisci removed. Appel (1970) found that the frequency of unsatisfactory r e s u l t s between medially and l a t e r a l l y meniscectomied knees was not s i g n i f i c a n t . S m i l l i e (1978, pp.185) found the long-term r e s u l t s of removal of the l a t e r a l meniscus les s favourable than the r e s u l t s on the medial side. The r e s u l t s of double meniscectomy were less good than for single meniscectomy. ( S m i l l i e , 1978, pp.187). Wynn Parry, et a l (1958) found 1% times the incidence of r a d i o l o g i c a l o s t e o a r t h r i t i s i n the short run with l a t e r a l c a r t i l a g e tears (4.4%) as compared to medial c a r t i l a g e tears (2.9%). 8. Sex Factors The r e s u l t s of meniscectomy i n general are less favourable i n women than i n men. ( S m i l l i e , 1978, pp.187, Tapper and Hoover 1969, Appel 1970, Johnson, et a l 1974). S m i l l i e suggests that the poor r e s u l t s may be due to the misdiagnosis of meniscus tear i n the case of subluxating p a t e l l a . -17-9. The E f f e c t s of T o t a l Versus P a r t i a l Meniscectomy There i s a growing controversy over the r e l a t i v e effectiveness of p a r t i a l as compared to t o t a l meniscectomy. S m i l l i e (1978, pp.153) advocates complete removal of the meniscus i n a l l cases; however, i f there i s v i r t u a l c e r t a i n t y that only one tear e x i s t s , then only the displaced portion of a bucket-handle tear can be removed, leaving the peripheral rim untouched. Tapper and Hoover (1969) found no difference i n the proportion of o v e r a l l excellent or good r e s u l t i n those patients who had undergone p a r t i a l meniscectomy as compared with those who had undergone t o t a l meniscectomy, except i n the case of a bucket-handle tear. In the l a t t e r s i t u a t i o n , removal of the detached fragment only, leaving the peripheral rim i n t a c t , y i e l d e d the highest percentage of excellent knees. Leaving the p o s t e r i o r horn i n t a c t gave fewer excellent r e s u l t s , and several patients (who Tapper and Hoover eliminated from the study of longr-term r e s u l t s ) required further surgery to remove the po s t e r i o r horn. Johnson, et a l (1974) found no observable difference between removing the e n t i r e meniscus i n 79 cases, or leaving the peripheral rim of a bucket-handle tear i n s i x cases. However, leaving the p o s t e r i o r horn within the knee led to unsatisfactory r e s u l t s i n a l l seven of the knees i n which i t was done. When comparing the r e l a t i v e postoperative morbidity of 89 t o t a l meniscectomies to 39 p a r t i a l meniscectomies, McGinty, et a l (1977) found four times the incidence of major postoperative complications, such as thrombophlebitis, embolus, or i n f e c t i o n , i n those who had experienced t o t a l meniscectomy. P a r t i a l meniscectomy yi e l d e d better subjective f u n c t i o n a l r e s u l t s , and better anatomical r e s u l t s , than t o t a l meniscectomy. P a r t i a l meniscectomy may y i e l d better r e s u l t s than complete because i t i s less damaging to the j o i n t (Jackson 1976). P a r t i a l meniscectomy may have a biomechanical advantage because there i s less a l t e r a t i o n i n load-bearing within the knee j o i n t (Norris 1978). Dandy (1978) advocates p a r t i a l meniscectomy through a closed technique under arthroscopic c o n t r o l . In h i s study of 30 patients who had undergone th i s procedure, the mean time for return to work f i t n e s s was only 10.5 days. Jackson, too, advocates t h i s procedure. However, t h i s technique was not encountered i n the present study. -18-10. The E f f e c t s of Posterior I n c i s i o n Comparing 64 complete meniscectomies performed through a si n g l e capsular i n c i s i o n to 15 complete meniscectomies performed through two capsular i n c i s i o n s , Johnson, et a l (1974) noted no difference i n r e s u l t s . 11. Unnecessary Meniscectomy An e d i t o r i a l i n The Lancet of January 31, 1976, notes that many menisci which are not torn are being removed. Removal may predispose the j o i n t to other problems l a t e r . In a c l i n i c a l and roentgenological exami-nation of 30 patients who had experienced unsatisfactory r e s u l t s following meniscectomy, Laarsen and W i l p u l l a (1976) found another l e s i o n i n four cases. In these four cases, the meniscus had been found to be i n t a c t at the time of operation. Commenting on the increasing occurrence of reconstructive surgery following simple meniscectomy, Houston (1975) believes that i n some cases there i s obviously more than a simple torn meniscus as the i n i t i a l pathology, or the i n i t i a l pathology was other than a torn meniscus. In h i s study of 4500 meniscectomies, S m i l l i e (1978, pp.142-143) found 183 cases i n which the meniscus was apparently normal i n every respect. The largest category of e r r o r s , 44 cases, were c l a s s i f i e d as "unexplained". Another 37 cases were blamed on the "unreliable witness". Under t h i s category were m i l i t a r y personnel i n World War I I , and inmates of j a i l s , "but most of a l l , claimants for compensation of alleged i n d u s t r i a l accidents and i n d u s t r i a l d i s a b i l i t y pensions i n the Welfare State". 12. The Effectiveness of Postoperative R e h a b i l i t a t i o n i n the Treatment of  the Meniscectomy Patient S m i l l i e (1978, pp.173) recommends active physiotherapy i n the post-operative management of meniscectomy, but he cautions that progression i s the most important feature of successful r e h a b i l i t a t i o n . He advocates gradually increasing power-building exercises and endurance-building exercises. By the f i f t h week postoperative, and i n the absence of e f f u s i o n and with a steady increase i n muscle volume, weightbearing exercises, p h y s i c a l t r a i n i n g and games can be commenced. Helfet (1974) too, while recommending physiotherapy, cautions that overexertion and repeated fatigue r e s u l t i n muscle wasting and recurrent e f f u s i o n . -19-I Outerbridge (1964) believes that on rare occasions, a patient w i l l respond poorly to physiotherapy a f t e r meniscectomy because of the develop-ment of chondromalacia of the p a t e l l a . Five of the 240 patients i n h i s serie s who had normal or Grade I p a t e l l a r c a r t i l a g e at the time of operation developed severe chondromalacia of the p a t e l l a despite physiotherapy. He suggests that exercises against resistance which allow an increase i n the shearing forces of the p a t e l l a as i t rides over the condylar rim of the femur, should be avoided i n the early stages, and only introduced l a t e r when the knee has made good progress. Appel (1970) found that postoperative muscular t r a i n i n g gave r i s e to a s i g n i f i c a n t l y lower frequency of unsatisfactory r e s u l t s , i f the patients who had o s t e o a r t h r i t i s at the time of operation were excluded. However, several authors are questioning the "time-honoured" approach of routine physiotherapy postmeniscectomy. V i d a l and Dimeglio (1976) believe that meniscectomy does not j u s t i f y re-education because the operation i s too t r i v i a l . Seymour (1969) undertook a c l i n i c a l t r i a l to test h i s impression that meniscectomy patients not treated with physiotherapy postoperatively did as well as those who received physiotherapy. Seventy patients were divided randomly into two groups. The groups were roughly comparable i n the proportion of sedentary and manual workers. Effusions were found to be more common, larger, and of longer duration i n the group having physio-therapy than i n those not treated with physiotherapy. There was v i r t u a l l y no difference i n the average range of movement of the two groups, except when measured ten days postoperative when the compression bandage was i n i t i a l l y removed. At that time the range of movement was greater i n the group receiving physiotherapy. However, with removal of the compression bandage, e f f u s i o n set i n and no difference i n the two groups was found. There was no difference between the two groups i n the time of return to work, but f i v e patients i n the group receiving physiotherapy would have returned to work e a r l i e r had they not had to attend treatment sessions. Almost a l l patients i n both groups i n Seymour's study were undertaking nearly f u l l a c t i v i t i e s three months postoperative. Seymour concludes that postoperative physiotherapy i n the routine case i s of no value. He recommends that the patient do s t a t i c quadriceps exercises at home a few times a day. The benefit of quadriceps exercises was shown i n the i n i t i a l greater range of motion when the compression bandage was removed from the treated group. -20-In order to test the effectiveness of intensive physiotherapy i n the treatment of postoperative meniscectomy, Karumo (1976) divided 56 patients into two groups. The f i r s t group received "standard postoperative physio-therapy". This included quadriceps s e t t i n g exercises, s t r a i g h t leg r a i s i n g and crutch walking from the f i r s t day postoperative. Active f l e x i o n was begun from the second or t h i r d day onward. At approximately two weeks or when knee f l e x i o n measured 90 degrees, crutches were abandoned. Patients were trained i n stairwalking. The second group received the same treatment procedures, but twice d a i l y under the guidance of a physiotherapist. C l i n i c a l examinations of the knees of both groups of patients were conducted preopera-t i v e l y and at the f i r s t , second and fourth weeks postoperatively. There were no s t a t i s t i c a l l y s i g n i f i c a n t differences i n r e s u l t s . However, f l e x i o n strength of patients receiving the intensive treatment increased less i n four weeks than the f l e x i o n strength of the routine therapy group. Knee punctures were required more frequently for the patients receiving intensive therapy to c o n t r o l the e f f u s i o n s . Karumo concluded that intensive physio-therapy i n meniscectomy patients does not shorten the r e h a b i l i t a t i o n period. 13. Implications of the L i t e r a t u r e on Meniscectomy for the Present Study Meniscectomy i s one of the most common procedures performed by ortho-pedic surgeons (Huckel 1965, Johnson et a l 1974) but the l i t e r a t u r e review has shown that i t s e f f e c t s upon the knee j o i n t , and the i d e n t i f i c a t i o n of which variables determine these e f f e c t s , are the subject of controversy. The present study w i l l examine short-term e f f e c t s measured by return to work. While the main area of i n t e r e s t i s the e f f e c t of d i f f e r e n t approaches to postoperative r e h a b i l i t a t i o n , the l i t e r a t u r e has indicated that many variables must be incorporated into the research design. These w i l l be discussed i n Chaper III which describes the methodology for the study. C. A REVIEW OF THE LITERATURE ON THE EFFECTS OF COMPENSATION ON DISABILITY Compensation i s another v a r i a b l e which i s l i k e l y to a f f e c t the return to work time of the meniscectomy patient. For t h i s reason, the l i t e r a t u r e on the e f f e c t s of compensation on d i s a b i l i t y was reviewed. -21-1. The D i s t i n c t i o n Between Impairment and D i s a b i l i t y In order to understand the e f f e c t s that compensation may have upon d i s a b i l i t y , i t i s e s s e n t i a l to d i s t i n g u i s h p h y s i c a l impairment from d i s a b i l i t y . For the purpose of developing a framework for t h i s d i s t i n c t i o n , Nagi (1965) has d i f f e r e n t i a t e d the following phenomena: i ) Active Pathology: This i s the disease process at the molecular or c e l l u l a r l e v e l . It involves onset and the simultaneous e f f o r t s of the organism to restore i t s e l f to the normal process. i i ) Impairments: These are anatomical and/or p h y s i o l o g i c a l abnormalities and losses. These occur i n the active pathology stage. When active pathology ceases, such impairments may r e s u l t i n r e s i d u a l abnormalities. Examples are weakness or r e s t r i c t e d j o i n t motion. i i i ) Functional Limitations : These are the l i m i t a t i o n s which impair-ments impose upon the i n d i v i d u a l ' s a b i l i t y to perform h i s usual roles and normal d a i l y a c t i v i t i e s . These are dependent not only upon the type of impairment but the nature and requirement of roles within s o c i a l and occupational s e t t i n g s . For example, a s t i f f knee could be severely l i m i t i n g to a carpet layer but of l i t t l e or no consequence to a teacher. Thus, not every impairment r e s u l t s i n f u n c t i o n a l l i m i t a t i o n s . iv) D i s a b i l i t y : This i s a pattern of behaviour which evolves i n s i t u a t i o n s of long-term or continued impairments which are associated with functional l i m i t a t i o n s . The pattern of behaviour i s subject to three types of influence: a) the c h a r a c t e r i s t i c s of the impairments, the degree of l i m i t a t i o n imposed and the p o t e n t i a l f o r r e h a b i l i t a t i o n ; b) the i n d i v i -dual's d e f i n i t i o n of the s i t u a t i o n , and h i s reactions, which sometimes compound the l i m i t a t i o n s . The i n d i v i d u a l ' s d e f i n i t i o n of the s i t u a t i o n and his reactions are also influenced by c) the d e f i n i t i o n of the s i t u a t i o n by others, such as h i s family, agencies, employers, and t h e i r reactions and expectations. 2. The E f f e c t s of Compensation on the Recovery Process The payment of compensation a f t e r injury i s usually expected to delay the recovery process. (Behan and H i r s c h f i e l d 1963, Brodsky 1971, Krussen 1958, Tracy 1972, White 1966). Controlled studies of low back i n j u r i e s (Krussen 1958), surgery for lumbar disc syndrome (Hudgins 1964), -22-and a mix of p h y s i c a l and p s y c h i a t r i c d i s a b i l i t i e s (Fowler and Mayfield 1968) have a l l found that the payment of compensation res u l t e d i n le s s subjective improvement and less success i n returning to work. Krussen noted that patients receiving compensation received a greater number of treatments than those with no compensation. In Hudgins' study, compensated patients reported one-third as many excellent r e s u l t s and four times more poor r e s u l t s than non-compensated patients. On p s y c h i a t r i c examination Fowler and Mayfield determined that compensated patients receiving Veteran's Administration D i s a b i l i t y Compensation manifested fewer symptoms but had s i g n i f i c a n t l y poorer occupational adjustment, and s i g n i f i c a n t l y greater desire f or increased pensions and other "manipulative" gains. In a study of the e f f e c t s of intensive physiotherapy on outcomes a f t e r meniscectomy, Karumo (1977) found that while occupation did not a f f e c t the duration of si c k leave, the type of insurance coverage did. Nine of 30 patients with an occupational-trauma insurance experienced s i c k leave over 90 days, whereas only two of 23 patients covered by sickness insurance had si c k leave as long as t h i s . 3. The Causes of Delayed Recovery There i s l i t t l e empirical research which explains why the payment of compensation delays recovery. However, various theories based upon assumptions, d e s c r i p t i v e case studies, or personal observations have been suggested. These f a l l into categories blaming the patient, the physician and other health-care p r o f e s s i o n a l s , the workers' compensation system, or an i n t e r a c t i v e process of a l l these f a c t o r s . 4. The Workers' Compensation System The adversary system through which the compensation v i c t i m seeks treatment may a c t u a l l y impair the goals of compensation and r e h a b i l i t a t i o n ( N a f t u l i n 1970), The primary concern i n workers' compensation i s with the adjudication or l i a b i l i t y considerations and t h i s o r i e n t a t i o n generates a " l i t i g i o u s atmosphere". This breeds suspicion on the part of claimants, and uncertainty on whose behalf the agency i s operating. These attitudes on the part of the claimant are often generalized to the r e h a b i l i t a t i o n centres to which they are refer r e d . Under such conditions, i t i s d i f f i c u l t to e s t a b l i s h therapeutic r e l a t i o n s h i p s between c l i n i c a l personnel and the c l i e n t s . The content of r e h a b i l i t a t i o n becomes more forensic than c l i n i c a l -23-(Nagy 1965, pp.107). I f the worker i s not recovering, the system becomes more adversary, as i t t r i e s to determine i f he i s r e a l l y disabled or malingering. More expert opinion i s sought and more disagreement often r e s u l t s . ( N a f t u l i n 1970). The patients' primary concern under the compensation system i s to emphasize his d i s a b i l i t y and thus e l i g i b i l i t y for b e n e f i t s . However, he i s faced with the c o n f l i c t i n g demands of r e h a b i l i t a t i o n which asks him to consider his c a p a b i l i t i e s and assets. The system produces c o n f l i c t of i n t e r e s t i n the worker. (Nagi 1965, pp.108). The fear of losing compensation benefits without having recovered to the point of optimal function or permanent, stationary d i s a b i l i t y provides poor or ambivalent motivation for r e h a b i l i t a t i o n . ( N a f t u l i n 1970) . Gordon et a l (1973) stress that present-day attitudes and practices regarding d i s a b i l i t y payments perpetuate the dependency of compensation patients and i n t e r f e r e with t h e i r becoming r e h a b i l i t a t e d and developing worthwhile l i v e s f o r themselves. 5. Psychosocial Causes for Prolonged Recovery The p s y c h i a t r i c l i t e r a t u r e i s replete with various psychosocial explanations for the delayed recovery of the compensation patient. The l a b e l "traumatic neurosis" has been applied to accident victims. Common explanations for i t s appearance are: i ) that the s t r e s s f u l incident activates a latent i d i o s y n d r a t i c neurotic gain i n the patient; i i ) that the secondary gain of i l l n e s s sets i n , p a r t i c u l a r l y the dream of monetary compensation, and i i i ) that the psychosocial c h a r a c t e r i s t i c s of the v i c t i m predispose him toward "traumatic neurosis". (Modlin 1967). Behan and H i r s c h f i e l d (1963) believe that compensation patients do not come to physicians to be cured, because t o t a l r e l i e f of symptoms would represent a loss to the economic and psychosocial s o l u t i o n to t h e i r l i f e problems which compensation represents. Workers' Compensation gives t h i s reward not for the sake of i n j u r y , but for the loss of earning capacity. Therefore, the injured man f i g h t s to prove his incapacity by preserving his symptoms. Every claims o f f i c e r who i n t e r a c t s with the patient must by inference i n d i c a t e t h i s necessity to preserve incapacity, because under the law, incapacity i s the c r u c i a l issue, whether a patient wishes to recover, or whether he wishes to maintain a l e g a l l y valuable symptom, can determine many therapeutic courses, p a r t i c u l a r l y i n e l e c t i v e surgery. -24-( H i r s c h f i e l d and Bevan 1963). Beals and Hickman (1972) found a consistently p o s i t i v e r e l a t i o n s h i p between the severity of the actual p h y s i c a l d i s a b i l i t y and the patients' tendency to be evasive and d e c e i t f u l . They explain that the more severely injured patients are more dependent upon compensation and may therefore be attempting to ensure i t s continuation through exaggeration of t h e i r symptoms and the extent of t h e i r d i s a b i l i t y . The patient may be over-zealous i n h i s e f f o r t s to communicate his concerns. Studies of d i s a b i l i t y following i n d u s t r i a l accidents suggest an "accident process" i n which the acceptable p h y s i c a l d i s a b i l i t y of i n j u r y i s substituted for unacceptable psychosocial and emotional d i s a b i l i t i e s . (Behan and H i r s c h f i e l d 1963, Weinstein 1968). H i r s c h f i e l d and Behan (1963) propose an active dependency model, i n which workers with personality problems and a troubled l i f e s i t u a t i o n replace these unrewarded, unacceptable s o c i a l d i s a b i l i t i e s with a compensated, acceptable one. In Weinstein's model, medical impairment becomes an acceptable s o l u t i o n to the patient's longstanding c o n f l i c t s i n l i f e , as part of the " i l l n e s s process". Behan and H i r s c h f i e l d go so f a r as to suggest that the accident v i c t i m has w i l l e d the accident upon himself as a s o l u t i o n to l i f e ' s problems. In the active dependency model, the patient i s u n l i k e l y to give up his d i s a b i l i t y because of the s o l u t i o n i t represents. H i r s c h f i e l d and Behan believe that the patient a c t u a l l y seeks physicians who w i l l not cure him, and r e j e c t s others who o f f e r cure. Compensation law, which makes incapacity the cornerstone of continued f i n a n c i a l support, reinforces the patient's inner need to maintain his incapacity. Patients continue unproductive treatment with c e r t a i n physicians, and refuse aid from others who indicate the capacity to r e l i e v e the symptoms. H i r s c h f i e l d and Bevan believe that the patient i s usually aware of what he i s doing. Beals and Hickman (1972) performed a comprehensive evaluation and followup on a group of 180 i n d u s t r i a l l y injured patients and a group of noninjured workers to determine the extent to which psychological, vocational, p h y s i c a l , and other factors influenced return to work. They found s i g n i f i c a n t differences i n the psychological postures of back-injured, extremity-injured, and non-injured i n d u s t r i a l workers. However, t h i s study can be c r i t i c i z e d because the nature of the i n j u r y i t s e l f would a f f e c t the psychological states of the back and extremity-injured patients, and because workers who have not had an i n j u r y may not be a v a l i d c o n t r o l . - 2 5 -Beals and Hiekman favour the "whole man" concept In r e h a b i l i t a t i o n i n order to assess the many factors i n f l u e n c i n g the return to work of the injured worker. However, they do not recommend routine p s y c h i a t r i c consul^ t a t i o n because: i ) i t adds another s p e c i a l i s t to a l i s t already too long, i i ) the d i v i s i o n of the patient into the somatic and the psychic r e l i e v e s everyone but the p s y c h i a t r i s t of the r e s p o n s i b i l i t y for understanding the patient, i i i ) p s y c h i a t r i s t s cannot cure everyone, and iv) i t threatens the patient. Some authors question the stress placed upon psychosocial reasons for prolonged d i s a b i l i t i e s . Hudgins (1964) notes that many variables a f f e c t the r e s u l t s of lumbar disc surgery. He c r i t i c i z e s reports which implicate compensation as the cause of poor r e s u l t s because: i ) compensation patients may be subject to overdiagnosis and t h e i r poor r e s u l t s may be r e l a t e d to a higher incidence of negative findings at surgery, i i ) some compensation patients may receive conservative treatment for an unusually long time before operation, and thus prolonged root compression can adversely a f f e c t the r e s u l t s of surgery, i i i ) the compensation patient has often been injured doing manual labour, and may be unable to resume heavy work despite an otherwise successful operation; thus, i f s u r g i c a l r e s u l t s are c l a s s i f i e d by an a b i l i t y to return to work, the compensation patient would show poorer r e s u l t s than patients with sedentary occupations. N a f t u l i n (1970) strongly c r i t i c i z e s proponents of the "psychologically motivated" work-incurred i n j u r y , because such theories r e s u l t i n a medical and l e g a l a t t i t u d e too frequently accepted, and poorly documented. He believes that the physician who seeks psychological motivations to explain i n d u s t r i a l i n j u r i e s often does the patient a d i s s e r v i c e . He c r i t i c i z e s Weinstein's theory of p h y s i c a l impairment s u b s t i t u t i n g for emotional impairment of the worker, as a " s i g n i f i c a n t contribution to the medical l i t e r a t u r e " which r i s k s r e ceiving more causal s i g n i f i c a n c e than i t s state of v a l i d a t i o n deserves. Adequate outcome studies are required to predict i n which pre-existing personality type problems are l i k e l y to appear. E x i s t i n g research i s mostly d e s c r i p t i v e . There have not been c o n t r o l l e d double-blind outcome studies on the psychological e f f e c t s of compensations. These are necessary before such generalizations can be made. (N a f t u l i n 1970). -26-6. Malingering Malingering refers to people's behaviour when i l l n e s s or d i s a b i l i t y i s d e l i b e r a t e l y feigned i n order to gain some advantage, (Parker 1972). In s p i t e of the compensation patient's tendency toward deception, Beals and Hickman (1972) found malingering to be rare. They discount as a s i g n i f i c a n t factor i n the symptoms of the i n d u s t r i a l l y injured a conscious e f f o r t to defraud by describing symptoms which are not t r u l y present. Rather, the patient shows an exaggeration of symptoms and the e f f e c t s of the d i s a b i l i t y , and an overzealousness i n h i s e f f o r t s to communicate these concerns. Krussen (1958) also believes that, with rare exception, compensation patients are not malingering, but rather they seem to be s u f f e r i n g a "compensation neurosis". Mossman (1973) suggests that t h i s " s o - c a l l e d compensation neurosis" i s not at a conscious l e v e l . The malingerer i s uncommon i n h i s experience. Using arthroscopy to diagnose problems a f t e r meniscectomy, Dandy (1978) found that although seven cases were considered h y s t e r i c s or malingerers before arthroscopy, i n f i v e of these an abnormality was found, "with obvious benefit to the patient". Szasz (1974, pp.60-61) writes that the diagnosis of malingering i s more l i k e l y to be made i n the Soviet Union, where doctors are servants of the State, than i n North America, where doctors are the servants of the i n d i v i d u a l . Malingering i s thus considered more of a s o c i a l condemnation than a diagnosis. 7. The E f f e c t s of L a b e l l i n g The "patient" l a b e l i s often demeaning to the worker who may have d i f f i c u l t y accepting h i s p a s s i v i t y . The "claimant" l a b e l may be even more demeaning. The worker perceives i t as a necessity to j u s t i f y h i s i n j u r y rather than to recover from i t . Labels such as "claimant" may undermine the worker's self-esteem, r e s u l t i n g i n c o n f l i c t s centered around hi s f e e l i n g of p a s s i v i t y and dependency. (Naft u l i n 1970). N a f t u l i n described the e f f e c t s of l a b e l l i n g as follows: "The disabled becomes both patient and claimant,... In addition, the ambiguity i s compounded when the medical treatment program becomes i d e n t i f i a b l e with the claim." -27-8. Secondary Gain Secondary gain from compensation i s generally considered f i n a n c i a l . However, other gains have been suggested. The i n d u s t r i a l accident may be a means to escape to a "retirement" status. Brodsky (1971) recommends that physicians and r e h a b i l i t a t i o n workers r e a l i z e that occupational i l l n e s s i s a retirement channel for workers with l o w - s k i l l e d jobs. Agencies respond by accepting t h e i r symptoms and t r e a t i n g the compensation patient as i l l persons rather than as people i n the process of changing jobs and l i f e s t y l e s . Lump-sum settlement, rather than weekly b e n e f i t s , i s favoured by many professionals i n the f i e l d of r e h a b i l i t a t i o n because i t may motivate the worker to r e h a b i l i t a t e himself, and to return to the old job or a new one. The continuance of weekly payments i s often an obstacle to r e h a b i l i -t a t i o n because there i s no incentive to return to work. (Curran 1970). Because of the attitudes engendered by the image of the "freeloader", the e f f e c t of secondary gain often produces h o s t i l i t y and therapeutic n i h i l i s m . Every symptom has many determinants and secondary gain as i t relates to compensation, i s but one of them. (Martin 1974). 9. Secondary Losses C r i t i c i z i n g the concept of secondary gain as the r a t i o n a l i z a t i o n of everyone working with the compensation case, Martin (1974) suggests considering secondary losses. The compensation patient s u f f e r s the loss of respect from those i n the helping r o l e s , and the loss of community approval. He endures the s o c i a l stigma and g u i l t inherent i n the r o l e of being c h r o n i c a l l y disabled. The physician too loses i n t h i s process. Lack of response on the part of the patient lowers the physician's s e l f -perception as healer, f r i e n d , and counsellor. These uncertainties produce feelings of h o s t i l i t y and cynicism toward the p a t i e n t . Martin believes that physicians resort to r a t i o n a l i z a t i o n about the p a t i e n t s ' u n t r e a t a b i l i t y i n order to comfort themselves. 10. Physician/Patient Dynamics Compensation has i t s e f f e c t s on physician behaviour. In workers' compensation, the doctor-patient r e l a t i o n s h i p i s subordinate to the adversary process whereby the patient i s f i g h t i n g to e s t a b l i s h e l i g i b i l i t y for benefits which include the r i g h t to remain disabled. (Mossman 1973). -28-Unlike the treatment conditions of most patients, the injured worker i s treated i n a complex arena of c o n f l i c t i n g agencies. The effectiveness of diagnosis and treatment i s most often negated by complications i n the doctor-patient r e l a t i o n s h i p . Economic and l e g a l factors can poison t h i s r e l a t i o n s h i p . (Enelow 1968), The doctor^patient r e l a t i o n s h i p i s t r a d i t i o n a l l y a two-person compact. The insurance c a r r i e r i n workers' compensation complicates t h i s r e l a t i o n s h i p . (Enelow 1968). The doctor perceives himself as f r i e n d , healer, and counsellor. The compensation patient sees an enemy, and sets out to f o o l the doctor. The physician, uncertain of h i s status, becomes h o s t i l e and c y n i c a l toward the patient. This r e s u l t s i n a c i r c l e of h o s t i l i t y plus counter-angry reaction. (Behan and H i r s c h f i e l d 1963). The patient views the physician not as his own, but as the insurance c a r r i e r ' s . ( N a f t u l i n 1970) , Behan and H i r s c h f i e l d add " g u i l t " to explain physician/patient dynamics. The patient f e e l s g u i l t because he caused the accident. He unconsciously goads the doctor into a f f l i c t i n g more abuse upon him. The doctor reacts with more uncertainty and h o s t i l i t y . He too feels g u i l t y and there i s no chance of rapport between physician and patient. The physician's p r o f e s s i o n a l education has taught him to suppress fe e l i n g s of h o s t i l i t y toward a patient. He overcompensates by ordering extra tests , more medication and more physiotherapy. This r e s u l t s i n deleterious multiple somatic treatment. (Behan and H i r s c h f i e l d 1963). The patient i s r e f e r r e d to numerous s p e c i a l i s t s f or repeat examinations. The burgeoning chart, the c h r o n i c i t y of d i s a b i l i t y , the prestige of the previous examiners, and the patient's f u t i l i t y diminishes the s p e c i a l i s t ' s enthusiasm. The patient senses t h i s . He i s asked questions which suggest that he might be malingering or " p s y c h i a t r i c " . This adds to the patient's h o s t i l i t y . ( N a f t u l i n 1970). The accident process has been found to a f f e c t p h y s i c i a n s ' a t t i t u d e s . Frustrated doctors f a l l into non-therapeutic attitudes when faced by these angry, h o s t i l e p atients. Research on the e f f e c t of t h i r d p a r t i e s on the accident process and the physician's natural reaction to i t are indicated. ( E d i t o r i a l i n JAMA, October 1963). The b e s t - q u a l i f i e d physicians, defined as those b o a r d - c e r t i f i e d i n t h e i r s p e c i a l t i e s , have been found to avoid handling workers' compensation because they allege a c e r t a i n odium attached to that kind of p r a c t i c e (Carrol 1969). Physicians' attitudes toward monetary compensation seems to be unchanged since the l a t e nineteenth century. The idea that the patient i s b e n e f i t t i n g from his i l l n e s s creates the f e e l i n g that the patient does not deserve the consideration accorded " r e a l l y s i c k people". Rather, these patients e l i c i t "contemptuous, abrupt, and c u r t " manners from physicians. (Martin 1974). Because prolonged therapy i s f i n a n c i a l l y rewarding for the physician, Behan and H i r s c h f i e l d wonder i f physicians as well as patients unconsciously gain from chronic i l l n e s s . The challenge to the physician i s to treat the i n d u s t r i a l disease properly, but not to overtreat. (Mossman 1973). 11. A S i t u a t i o n a l Explanation for Prolonged D i s a b i l i t y Unfortunately, the experiences and behaviour of injured people are considered p s y c h i a t r i c problems, and described i n the conventional l i m i t s of a disease model. They might be more r e a d i l y understood as s i t u a t i o n a l problems, influenced not only by the immediate and remote stress of the i n j u r y , but also by the s o c i a l and l e g a l consequences of the accident. The recognition that a few people w i l l simulate accident or incapacity for t h e i r own p r o f i t has tended to obscure the unpleasant experience undergone by a great many others who would welcome r e l i e f before reward. (Cole 1970). APPLICATION OF THE LITERATURE TO THE PRESENT STUDY The programme evaluation l i t e r a t u r e has described the goal model. Chapter I I I , Study Methodology, explains how return to work as an outcome measure i s w e l l - s u i t e d to t h i s model. Those variables which may a f f e c t the outcome of meniscectomy have been i d e n t i f i e d through the l i t e r a t u r e , and Chapter III describes the methods by which these are incorporated into the design of the study. The l i t e r a t u r e concerning the e f f e c t s of compensation on recovery i s applied i n the Discussion of Study Findings i n Chapter VI. -30-CHAPTER III STUDY METHODOLOGY I In order to determine the effectiveness of r e h a b i l i t a t i o n , outcomes measured i n return to work time for three groups of postoperative meniscec-tomy patients were compared. Those patients treated at the WCB C l i n i c were compared to WCB patients treated i n the community, i n order to determine how the r e h a b i l i t a t i v e s e t t i n g affected return to work time. Outcomes of both groups were then compared to outcomes of those WCB patients who did not receive formal p h y s i c a l therapy i n order to determine the general effectiveness of postoperative r e h a b i l i t a t i o n . Return to work as the c r i t e r i o n of evaluation f i t s the goal attainment model for programme evaluation. In an introduction for medical s t a f f from the WCB Administration Building v i s i t i n g the C l i n i c i n A p r i l 1979, Dr. L.H. B a r t l e t t , Medical Director of the C l i n i c since January 1979, described i t s goals as follows: "The purpose of the program i s to speed the worker's recovery and return to work." Thus, the choice of return to work as a measure of goal attainment f u l f i l s the c r i t e r i a suggested by Schulberg et a l (1964) and Goldberg (1974). Return to work as a goal i s measurable, p r a c t i c a l and relevant and i t can be a c r i t e r i o n of the WCB i n measuring performance. Threats to v a l i d i t y due to the e f f e c t s of receiving compensation were eliminated by including only compensation patients i n the study. Confounding variables of age, sex, occupation, income, degenerative changes, medial or l a t e r a l e x c i s i o n of the meniscus, h i s t o r y , latency, preoperative r e h a b i l i t a t i o n , complete or p a r t i a l meniscectomy and presence of posterior i n c i s i o n , were c o n t r o l l e d as described i n the following sections. A. POPULATION AND SAMPLE In 1976 and 1977, the WCB paid medical aid for 1,029 meniscectomies; 454 of these were from the Lower Mainland. These 454 cases form the sample for t h i s study. Patients from outside the Lower Mainland were excluded because i f these patients are referred to the WCB C l i n i c , there e x i s t s the added psychological d i f f i c u l t y of l i f e away from family i n the WCB residence. The i n c l u s i o n of resident patients would thus threaten the v a l i d i t y of the study. Patients from Sechelt, Gibsons and Squamish, although c l a s s i f i e d by -31-the WCB as Lower Mainland, were also excluded because they usually l i v e i n residence i f r e f e r r e d to the C l i n i c . Those patients with h i s t o r i e s of major previous orthopedic problems with complicating pathologies of the same leg were excluded from the com-parisons. However, patients with r a d i o l o g i c a l or s u r g i c a l l y v i s u a l i z e d evidence of o s t e o a r t h r i t i s of the knee were included i n the study. This group was, categorized according to s e v e r i t y , as w i l l be described further on i n t h i s chapter. It would have been preferable to exclude a l l cases with any minor h i s t o r y of knee i n j u r y . However, t h i s would have caused the numbers to dwindle too low. The incidence of minor h i s t o r i e s and the methods of c o n t r o l f or t h e i r e f f e c t s upon return to work w i l l be described l a t e r i n t h i s chapter. Those patients who underwent other s u r g i c a l procedures at the time of operation, except for those of a very minor nature, (such as reefing of the capsule, scraping of the panus, or removal of a cyst of the synovium) were excluded from the study. In addition, any case with a major postopera-t i v e complication, such as thrombophlebitis, was also excluded. Minor postoperative complications, such as s u p e r f i c i a l wound i n f e c t i o n s , upper resp i r a t o r y t r a c t i n f e c t i o n s and the such, were included i n the study for three reasons. F i r s t , they can be part of a usual course of postoperative recovery. Second, the incidence of these was very much greater i n C l i n i c patients because of better reporting. Exclusion of these cases would have thus resulted i n a very small sample of C l i n i c patients. Third, exclusion of cases of minor postoperative complications would have resulted i n very few t o t a l cases remaining to be studied. Any case which underwent further surgery at a l a t e r date, (such as patellectomy or removal of a remnant of the meniscus) was removed from the study. In addition, one patient who was strongly advised to undergo a Slocum procedure postoperatively but who refused, was also excluded. One case developed ulnar nerve palsy at the time of operation. However, neither the patient nor the physician was too concerned about the palsy, and since i t did not delay return to work, t h i s case was included. Many of the torn meniscus cases were o r i g i n a l l y l i s t e d by the WCB as "multiple" problems because of various other i n j u r i e s to the body at the time of accident. Cases where the other i n j u r i e s remained a problem were excluded from the study. I f the other problem r a p i d l y cleared and only the knee remained a concern, then these cases were included. -32-The number of women i n t h i s study was so small that i t was decided to exclude them rather than include another v a r i a b l e , which might confound the r e s u l t s . Also excluded were cases which were a c t u a l l y removal of a remnant or removal of the opposite meniscus following i n i t i a l meniscectomy performed i n the period from 1973 to 1975. Some of the meniscectomies had been performed e i t h e r i n 1974 or 1975, but because of administrative delays, medical aid was not paid u n t i l 1976. A l l s u r g i c a l procedures performed a f t e r September 1, 1975, were included i n t h i s study. However, the few cases performed i n e i t h e r 1974 or e a r l i e r i n 1975 were excluded because the researcher wished to examine outcomes within a s i m i l a r time frame i n order to eliminate threats to v a l i d i t y due to h i s t o r i c a l events such as labour s t r i k e s which might a f f e c t motivation to return to work. Cases i n which the claim was accepted only a f t e r the patient had returned to work were also excluded. I t was f e l t that return to work incentive for these patients d i f f e r e d s i g n i f i c a n t l y since they were not receiving f i n a n c i a l support i n the postoperative period. In another instance, the patient was also awaiting a settlement with the Insurance Corporation of B r i t i s h Columbia. Again t h i s may have provided a d i f f e r e n t f i n a n c i a l motivation than other patients were re c e i v i n g , and i t was decided to exclude t h i s case. In one case the patient, the physician, and the WCB a l l agreed that the patient was ready to return to work. However, the patient was a P r o v i n c i a l Government employee, and confusion about return to work p o l i c y for i n d u s t r i a l l y - i n j u r e d employees i n the P r o v i n c i a l service resulted i n the patient not returning to work. The attending physician l a b e l l e d t h i s a "bureaucratic block" to return to work, and t h i s case was removed from the study. One patient was found to be working throughout much of h i s period of time l o s s . This was pursued as a case of fraud, and the patient was excluded from the study. Two cases were b i l l e d erroneously as meniscectomies, but rather were other arthrotomies and therefore excluded. In another case the patient underwent repeat meniscectomies on the same knee within a two-day period and he too was excluded. F i n a l l y , one case i n which the surgeon admitted that the meniscus was normal at the time of operation, and that the i n i t i a l problem was probably -33-not a torn meniscus, was removed from the study. Exclusion of those cases which were i n a s i t u a t i o n which might confound return to work resulted i n a f i n a l sample of 285 cases. Table 3.1 l i s t s a l l cases excluded from the study. I B. DESIGN The study examined records (a " r e t r o s p e c t i v e " study) and made comparisons among groups whose assignment was non-random. V a l i d i t y i s l e a s t threatened by a prospective experimental randomized c o n t r o l group design i n which postoperative meniscectomy patients would be randomly assigned to the WCB C l i n i c , a selected community f a c i l i t y , or to no p h y s i c a l therapy at a l l . However, t h i s i s not f e a s i b l e because the WCB allows both the surgeon and the patient the freedom of choice of treatment. In addition, a l o n g i t u d i n a l study would have been more expensive. It would take time to b u i l d up a study population. The study was designed to achieve i t s objectives by the following techniques: 1. Approach to R e h a b i l i t a t i o n The number of days before return to work of WCB C l i n i c patients was compared to the number of days before return to work of the WCB community-treated patients. Return to work for these two groups were then compared to the r e s u l t s for those WCB patients who received no postoperative menis-cectomy r e h a b i l i t a t i o n . These comparisons determined o v e r a l l short-term outcome of the r e h a b i l i t a t i o n process. 2. Time Intensity Time i n s t e n s i t y i s one of the c h a r a c t e r i s t i c s of process which d i s -tinguishes the C l i n i c from most community f a c i l i t i e s . However, there are some cases which are treated d a i l y i n the community. Thus outcomes for community patients treated time i n t e n s i v e l y (defined as treatment 4 to 5 times per week) were compared to outcomes for community patients treated 2 or 3 times per week. Comparisons of outcomes of intensive treatment only for community patients allows for an examination of one component of C l i n i c treatment, that i s i n t e n s i t y , i n a non-Clinic s e t t i n g . -34-Table 3.1 Cases Excluded From the WCB Meniscectomy Study I Category Numbers of Cases I Women 29 I I Squamish, Sechelt or Gibsons 17 V i c t o r i a 2 I I I Removal remnant from previous meniscectomy 3 Removal of opposite meniscus from previous meniscectomy 3 IV Surgery p r i o r to September 1, 1975 7 V Cases who underwent meniscectomy plus: - shaving of p a t e l l a , condyles, exostoses, osteophytes or j o i n t debridement 17 - ligamentous tr a n s f e r s , reconstructions, or repairs 14 - repair ruptured p o s t e r i o r capsule 1 - hand surgery for other claims 2 34 VI Postoperative complications re l a t e d to surgery - thrombophlebitis 6 VII Complications delaying return to work, but not rel a t e d to claim - stomach problems and kidney i n f e c t i o n 1 - e x c i s i o n osteoid osteoma, trochanteric region 1 - osteosarcoma, femur 1 - Crohn's disease 1 - inguinal hernia repair 1 - a systemic disease, not yet diagnosed ( d i f f e r e n t i a l diagnosis p o s t - v i r a l myositis) 1 - myocardial i n f a r c t i o n 1 - alcoholism 1 - ankylosing s p o n d y l i t i s plus peripheral j o i n t inflammation 1 9 VIII Previous h i s t o r y , same knee - long h i s t o r y of b i l a t e r a l chondromalacia 1 - old torn medial c o l l a t e r a l ligament 1 - old fracture of p a t e l l a plus chondromalacia 1 - patellectomy or p a r t i a l patellectomy 2 - pes anserinus t r a n s f e r , same knee 1 - multiple soccer i n j u r i e s with persistent problems 1 7 (continued on next page...) -35-Table 3.1 (continued) Category Numbers of Cases IX Other h i s t o r y - h i s t o r y of gout, p e r s i s t i n g through claim 1 - opposite knee medial meniscectomy with persistent problems 1 - back i n j u r y , a f t e r knee in j u r y but previous to surgery which pe r s i s t e d postoperatively and delayed return to work • 1 17 X Other pathologies - torn anterior cruciate 9 - torn posterior cruciate 1 - fracture of p a t e l l a 1 - multiple i n j u r i e s 6 XI Administrative causes for exclusion - claim accepted a f t e r patient returned to work 4 - f i l e unavailable because at boards of review 1 - "bureaucratic block" to return to work 1 - fraud 1 - ICBC case, awaiting settlement 1 XII Further surgery required a f t e r i n i t i a l meniscectomy - removal remnant 1 - removal other meniscus 2 - p a t e l l a r shaving 1 - patellectomy 2 - high t i b i a l osteotomy 2 - l a t e r a l meniscectomy, pes p l a s t y , and advancement and tightening of medial ligament 1 9 XIII Same claim number l i s t e d i n duplicate because of further operation 6 XIV F i l e s at area o f f i c e s 4 XV Miscellaneous - patient refuses Slocum procedure 1 - meniscus normal at surgery and not the cause of problems 1 - other s u r g i c a l procedures, no meniscectomy 2 - patient underwent b i l a t e r a l meniscectomies on the same knee within two days 1 TOTAL: 169 -36-3. Explanatory Factors A d d i t i o n a l to Postoperative R e h a b i l i t a t i o n B u i l t into the analysis of return to work time are the various con-founding variables of age, latency period, degrees of degenerative changes, medial or l a t e r a l e x c ision of the meniscus, preoperative r e h a b i l i t a t i o n , t o t a l or p a r t i a l meniscectomy, income, occupation, presence of pos t e r i o r i n c i s i o n , and previous h i s t o r y . The s i g n i f i c a n c e of the factors when analysed by the mu l t i v a r i a t e approach determined t h e i r r e l a t i v e c o n t r i b u t i o n for return to work time. 4' Cost and Benefits Cost/benefits within the d i f f e r e n t approaches were determined by costing treatment i n the d i f f e r e n t f a c i l i t i e s . Besides d i r e c t payment costs, the hidden costs to the organization and the patient were considered. In the period under study, the charges f or treatment changed. Rather than costing each treatment at i t s actual charges, the number of treatments for each patient was calculated, a l l cases were aggregated and then the charges f o r treatment at the end of 1977 were applied. This method does not give the exact cost that the WCB paid to r e h a b i l i t a t e t h i s group of patients; however, i t does show the r e l a t i v e expense of the d i f f e r e n t approaches. The design model i s conceptualized i n Figure 3.1. It i s possible to f i t a comparison of the e f f e c t s of a u n i d i s c i p l i n a r y and m u l t i d i s c i p l i n a r y approach within the C l i n i c into t h i s model, because not a l l C l i n i c patients were treated by a l l the d i s c i p l i n e s . However, there i s no v a l i d i t y to this comparison because the longer a patient i s treated at the C l i n i c , the more l i k e l y he i s to encounter a l l the d i s c i p l i n e s . The i n a b i l i t y to separate the team component from other aspects of WCB C l i n i c treatment remains a l i m i t a t i o n of the study. C. INSTRUMENTATION AND DATA COLLECTION A l l data was obtained from the records of the WCB. This study was not an evaluation of record keeping. However, av a i l a b l e data i s an i n d i c a t i o n of the completeness of the record. A d e s c r i p t i o n of a v a i l a b i l i t y w i l l be found i n the Appendix. A l l recording and^ coding was done by the researcher. Certain areas presented measurement or categorization problems. These were resolved as follows: Figure 3.1 Design Model  for the Evaluation of R e h a b i l i t a t i o n Outcomes  of WCB Meniscectomy Cases -37-No Physical Therapy time intensive s i n g l e d i s c i p l i n a r y u n i d i s c i p l i n a r y m u l t i d i s c i p l i n a r y time intensive ^~ -^non time intensive Key < } comparison ^ components -38-1. Return to Work Return to work was measured by calendar days rather than time loss days.* The f i r s t postoperative day, that i s the f i r s t day a f t e r surgery, | was counted as Day #1. Measuring the number of days return to work was d i f f i c u l t i n seven cases because the patient attempted to return to work, was unable to cope, and went back on another period of wage l o s s . It was decided that i f the patient worked for 30 days or more, the f i r s t return to work would be recorded as the return to work time. However, i f he returned to work for less than 30 days, then the i n i t i a l period of time l o s s , the days working, and the f i n a l period of time loss would be counted as the t o t a l time loss between operation and successful return to work. The 30-day figure i s somewhat a r b i t r a r y , but aside from excluding these cases, i t was f e l t that i t was a reasonable method of handling them. Because the study attempted to i n d i c a t e i f any method of r e h a b i l i t a t i n g the Compensation patient i s more e f f e c t i v e i n aiding return to work, i t was f e l t that a 30-day period of work would be considered a successful re-entry into the work force. Table 3.2 explains the return to work decisions on these seven patients. In addition, t h i s table includes an eighth patient who returned to work half-time. In t h i s case the i n i t i a l return to work half-time i s recorded as the return to work. Table 3.2 also indicates whether these cases were C l i n i c , community, or non-treated patients to show what bias t h i s method of measuring return to work might have on the outcome of t h i s study. Because i n most cases the patient returned to work for 30 days or longer, and the s p l i t i s f a i r l y even between community and C l i n i c p atients, i t i s suggested that the v a l i d i t y of t h i s study was not threatened by t h i s approach. 2. Locale of R e h a b i l i t a t i o n In 23 instances the patient's i n i t i a l postoperative r e h a b i l i t a t i o n was begun i n one l o c a l e before r e f e r r a l to another. Usually t h i s occurred because the attending physician waited u n t i l the patient was able to t r a v e l long distances before r e f e r r i n g him to the C l i n i c . In other cases there was no r e h a b i l i t a t i o n for a long period, or the patient was treated Because calendar days are used, i t i s possible that return to work i n the i n d i v i d u a l case i s delayed two days due to a non-work day, such as a weekend or holiday. This can a f f e c t outcome of the study s l i g h t l y ; however i t i s assumed that a l l groups are affected equally. I B 3.2 Decisions on Mu l t i p l e Return to Work Number Type of Number of Days Plus Number Plus Number Equals T o t a l Number of Days Postoperative Postoperative of Days of Days Before Number of Days Return to Work Therapy I n i t i a l at Work Second Return Before F i n a l Measured for Return to Work to Work Return to Work This Study 1. No p h y s i c a l 31 10 19 60 60 therapy 2. C l i n i c 242 32 65 339 242 3. Community 42 30 18 90 42 4. C l i n i c 116 43 89 248 116 5. C l i n i c 130 34 16 180 130 6. Community 60 45 116 221 60 7. Community 89 23 75 187 187 8. C l i n i c 155 29 184 155 (1/2 time) I Co I -40-unsuccessfully for an extended period of time i n the community before being referred to the C l i n i c . L a b e l l i n g a patient as a C l i n i c patient who had a c t u a l l y undergone 12 weeks of no therapy before being r e f e r r e d to the C l i n i c for four weeks of therapy would be inaccurate, because the 16 weeks before return to work a c t u a l l y indicates a f a i l u r e of the no-post-operative r e h a b i l i t a t i o n approach to get the patient back to work. The l i t e r a t u r e predominantly suggests the eight-week mark as the average time of return to work a f t e r meniscectomy. Therefore i t was decided to c l a s s i f y the l o c a l e of r e h a b i l i t a t i o n according to where the patient was at eight weeks. Table 3.3 gives the r e h a b i l i t a t i o n h i s t o r i e s of the 23 cases which were thus r e c l a s s i f i e d . "No p h y s i c a l therapy" s i g n i f i e s no formal approach to postoperative r e h a b i l i t a t i o n . However, i t i s r e a l i z e d that many of these cases were prescribed home exercises by t h e i r attending physicians, to be done at home unsupervised. 3. Measurement of Degenerative Changes The system employed to c l a s s i f y o s t e o a r t h r i t i s was a modified version of the system of Kellgren and Lawrence (1957) for the r a d i o l o g i c a l assess-ment of o s t e o a r t h r i t i s . The system employed was as follows: i ) None: A d e f i n i t e absence of x-ray changes of o s t e o a r t h r i t i s , i i ) Minimal: O s t e o a r t h r i t i s d e f i n i t e l y present, but of minimal se v e r i t y . i i i ) Moderate: O s t e o a r t h r i t i s present, and of moderate severity, iv) Severe: O s t e o a r t h r i t i s present, and severe. Kellgren and Lawrence also include a category of doubtful between none and minimal. Although t h i s i s s u i t a b l e prospectively, a retrospective examination of records indicated that t h i s category was unnecessary because based upon the physician's statements, cases could rather be c l a s s i f i e d as none or minimal. An assessment of the degree of degenerative changes was derived by examining x-ray reports, arthrography reports and operative reports when a v a i l a b l e . Based upon the physician's d e s c r i p t i o n of fi n d i n g s , each report was then c l a s s i f i e d as "none", "minimal", "moderate", or "severe", depending upon the terminology which the physician used, or t h e i r equiva-lents - such as "a l i t t l e " f o r "minimal". In f i v e cases the physician -41-Table 3.3 C l a s s i f i c a t i o n of Type of Postoperative R e h a b i l i t a t i o n of Patients With M u l t i p l e Locales of R e h a b i l i t a t i o n Number of Cases R e h a b i l i t a t i o n History F i n a l R e h a b i l i t a t i o n C l a s s i f i c a t i o n Began C l i n i c therapy a f t e r more than 8 weeks of no postoperative r e h a b i l i t a t i o n No Physical Therapy Began Community therapy a f t e r more than 8 weeks of no post-operative r e h a b i l i t a t i o n No Physical Therapy Rehabilitated i n Community for more than 8 weeks before being referred to C l i n i c Community Treated i n the Community for less than or equal to 2 weeks, then referred to C l i n i c C l i n i c Treated i n the Community for more than 2 weeks but less than or equal to 4 weeks, then referred to C l i n i c C l i n i c Treated i n the Community for more than 4 weeks but less than or equal to 6 weeks before being r e f e r r e d to the C l i n i c C l i n i c 23 -42-did not use the terms "minimal", "moderate", "severe", or t h e i r equivalents but rather described the findings more generally. The researcher c l a s s i f i e d these as follows: In three cases where the findings were described as "some roughening or some osteoarthrosis", the cases were c l a s s i f i e d as "minimal". One report described "degenerative changes of the fragments of a m u l t i f i d p a t e l l a " . This was graded as minimal, i n the absence of any other findings. In another case the operative report mentioned "medial j o i n t degeneration", with no other explanation. However, an x-ray report four months previous to operation found the "medial j o i n t space narrowed i n comparison with the l a t e r a l , suggesting minor c a r t i l a g e damage. There was a small osteophytic spur p r o j e c t i n g from the i n f e r i o r margin of the po s t e r i o r p a t e l l a . M i n e r a l i z a t i o n i s somewhat decreased, suggesing disuse osteoporosis". This case was c l a s s i f i e d as minimal. Findings of degenerative changes i n the present study have been interpreted by many r a d i o l o g i s t s and many surgeons. I t i s r e a l i z e d that d e s c r i p t i o n of o s t e o a r t h r i t i s i s very subjective. Lawrence and Kellgren found great intraobserver differences i n t h e i r study of r a d i o l o g i c a l assessment of o s t e o a r t h r i t i s . This i s a weakness of retrospective study. Wherever possible the x-ray reports of the WCB r a d i o l o g i s t s were used, because these were the most d e t a i l e d and because fewer numbers of doctors were involved. In the absence of any mention of the state of the j o i n t , i t was graded as normal. It i s r e a l i z e d than an absence of the mention of degenerative changes does not necessarily mean that the j o i n t was normal. However, possessing no other information, the researcher was forced to c l a s s i f y no mention as no degenerative findings. An exhaustive examination of chondromalacia of the p a t e l l a was not within the scope of this study. However, chondromalacia of the p a t e l l a has been implicated as a factor i n the r e s u l t s of meniscectomy (Outerbridge 1963) . The diagnostic c r i t e r i a f o r the l a b e l chondromalacia vary, and again c l a s s i f i c a t i o n depends upon the subjective i n t e r p r e t a t i o n of the physician. Outerbridge (1961) c l a s s i f i e s chondromalacia as follows: Grade 1 - softening and swelling of the c a r t i l a g e . Grade 2 - fragmentation and f i s s u r i n g i n an area h a l f an inch or less i n diameter. Grade 3 - the same as Grade 2 but an area more than h a l f an inch i n diameter i s involved. -43-Grade 4 - there i s erosion of c a r t i l a g e down to the bone. This c l a s s i f i c a t i o n system was used i n t h i s study with some modifica-t i o n . Grade 1 was l a b e l l e d "minimal", Grade 2 and 3 were combined into a I category l a b e l l e d "moderate", and Grade 4 was l a b e l l e d "severe". When the physician described the chondromalacia as "minimal", "moderate", or "severe", that l a b e l was applied. However, i n cases where the condition was described but not graded, the researcher used Outerbridge's c l a s s i f i c a t i o n to l a b e l the cases. Thus, a d e s c r i p t i o n of "softening of the p a t e l l a " was l a b e l l e d as "minimal" chondromalacia. If the area of erosion was described as "some" or "small", i t was l a b e l l e d as "moderate", but more advanced involvement was l a b e l l e d "severe". Descriptions of chondromalacia of the p a t e l l a , femoral or t i b i a l condyles were i n i t i a l l y recorded separately. Because chondromalcia i s a form of j o i n t degeneration, these findings were then aggregated with the categorization of o s t e o a r t h r i t i s f o r each patient, to develop an o v e r a l l categorization of operative degenerative changes. The most severe cate-g o r i z a t i o n was the one used. Thus a hypothetical patient i i i whom no o s t e o a r t h r i t i s i s mentioned but who has minimal chondromalacia of the t i b i a l condyle and severe chondromalacia of the p a t e l l a , would be l a b e l l e d as a patient with severe degenerative changes. C l a s s i f i c a t i o n of degenerative changes from x-ray, arthrogram, arthroscopy or surgery were then aggregated i n order to derive the f i n a l c l a s s i f i c a t i o n of degenerative changes f o r each case. The s u r g i c a l findings superseded a l l other c l a s s i f i c a t i o n s , unless the x-ray report had mentioned degeneration, but the surgeon had f a i l e d to describe the state of the knee at operation. Arthrograms are considered the most d i f f i c u l t to i n t e r p r e t accurately and therefore the s u r g i c a l findings and x-ray reports superseded them. In most cases, arthroscopic findings were written concurrently with the s u r g i c a l report. 4. Preoperative R e h a b i l i t a t i o n Preoperative r e h a b i l i t a t i o n was measured by i n d i c a t i n g any encounter with p h y s i c a l medicine preoperatively. Cases where the patient underwent treatment at both the C l i n i c or i n the community were indicated as treatment i n both centres. The length of preoperative r e h a b i l i t a t i o n was not indicated. However, i f the preoperative treatment ended more than one year p r i o r to operation, t h i s was indicated as "remote". -44-D. LIMITATIONS OF THE STUDY I 1. Threats to Internal V a l i d i t y The basic concern of t h i s study i s to determine i f the type of treatment affected return to work. However, other factors aside from treatment may a f f e c t outcome. These threaten the " i n t e r n a l v a l i d i t y " of the study. For example, there could be no cont r o l f o r the d i f f e r e n t approaches or . s k i l l s of the many surgeons involved. A l l attempts at equivalence were made through m u l t i v a r i a t e analysis of the confounding variables r e l a t i n g to the study population (such as age or degenerative changes), but the fac t o r of r e f e r r a l patterns of d i f f e r e n t surgeons could not be con t r o l l e d . However, the numbers were s u f f i c i e n t l y large that many approaches and s k i l l s must have existed within the three groups of r e f e r r i n g doctors. Because of the regression e f f e c t , extremes of s k i l l regress toward the mean. F i n a l l y , there was no reason to assume that the s k i l l of a physician i s l i k e l y to govern h i s r e f e r r a l pattern. S i m i l a r l y one i n s t i t u t i o n , the WCB C l i n i c , was compared to many community f a c i l i t i e s ( h o s p i t a l outpatient departments and priv a t e c l i n i c s ) . The study could not cont r o l for the s k i l l s of each l o c a l e , and i t was recognized that techniques of treatment d i f f e r e d somewhat i n each. However, i t was not possible to study a l i m i t e d number of community f a c i l i t i e s , because the sample population would have been too small and may not have been representative. Another threat to v a l i d i t y which has been discussed previously i n thi s chapter i s that degenerative changes have been interpreted by many physicians. This threatens v a l i d i t y because of problems of m i s c l a s s i f i c a t i o n . 2• The E f f e c t s of Occupation and Income Occupation and income are factors threatening i n t e r n a l v a l i d i t y because c e r t a i n socio-economic groups may be referred more to one lo c a l e than another. Occupation also threatens v a l i d i t y because return to work may be easier f o r c e r t a i n jobs, p a r t i c u l a r l y more sedentary type of work. However, f i t t i n g occupation into the model i n a retrospective study proved d i f f i c u l t f o r the following reasons. Although c e r t a i n occupations, such as a logger or accountant, have obvious p h y s i c a l requirements, other jobs were d i f f i c u l t to c l a s s i f y r e t r o s p e c t i v e l y . For example, the duties of a store c l e r k may or may not require climbing ladders or squatting. In addition, although c e r t a i n occupations are p h y s i c a l l y demanding i t was 1 not always known r e t r o s p e c t i v e l y i f the patient was returning to a modified job with l i g h t duties, or to f u l l duties. Indeed i t was not always known i f the patient t r u l y returned to h i s old job, any other job, or simply had his wage loss terminated. It was thus decided to show the occupational breakdown for the three groups of patients by "sedentary" or "non-sedentary" i n order to see i f there were s i g n i f i c a n t differences between the groups. Income i s a factor i n return to work because incomes above the maximum weekly time loss rate s u f f e r more wage loss on compensation than those below t h i s l e v e l . These losses may be an incentive to return to work. This approach to income loss i s based on the value-laden assumption that a $700 per month loss of income i s more of an incentive to return to work than a $300 a month loss of income. However, i t i s possible that the $300 per month loss has more of an impact on a p a r t i c u l a r worker's f i n a n c i a l health than a $700 per month loss has on another whose f i n a n c i a l p o s i t i o n i s more s o l i d . It i s also r e a l i z e d that the higher income earner may have private insurance subsidizing t h i s l o s s . Unfortunately, lack of knowledge of t h i s f actor i s a l i m i t a t i o n of t h i s study. Many of the high weekly wage earners are seasonal workers, and thus measuring income losses does not ind i c a t e i f they t r u l y would have been working through t h i s period. Income was measured not as wage earned but rather as the amount of known loss the patient was experiencing on compensation. I t thus included a consideration of possible cuts i n compensation a f t e r the i n i t i a l 13-week period on f u l l compensation which WCB claimants receive. 3. Latency The latency period, (that period between i n i t i a l i n j u r y and removal of the meniscus) may influence the outcome of meniscectomy. However, latency was not f i t t e d into the i n i t i a l m u l t i v a r i a t e equation for three reasons. The f i r s t i s that the s i g n i f i c a n c e of latency i n recovery may be r e l a t e d to i t s e f f e c t s on the development of degenerative processes within the knee. Because t h i s i s accounted for i n the measurement of j o i n t degeneration, i t was f e l t that i t was not necessary to include latency i n the i n i t i a l equation. In addition, latency i s a d i f f i c u l t f a ctor to c l e a r l y assess. The patient often cannot t e l l when onset began. For example, one of the recognized methods of i n j u r i n g a meniscus i s twisting while i n f u l l squat and while the meniscus i s caught between the condyles of the femur and t i b i a . -46-Such an injury can often occur i n a rug layer, f o r example, or anyone working i n t h i s p o s i t i o n , and the tear may occur i n s i d i o u s l y without h i s being aware of i t . The onset, not being dramatic, may be overlooked.* F i n a l l y , i t i s possible that the Compensation patient does not perceive i t as being i n his i n t e r e s t to report previous knee i n j u r i e s i n which the meniscus might have been torn. For t h i s reason, the latency period, as measured by the date of onset of the work i n j u r y , may be inaccurate. However, latency was f i t into further m u l t i v a r i a t e equations i n order to determine i f , within the above-mentioned l i m i t a t i o n s , i t appeared to have any e f f e c t upon return to work, 4. Previous History The study attempted to include a consideration of previous h i s t o r y of knee i n j u r i e s . However, again i t i s possible that the Compensation patient does not perceive i t as being i n his i n t e r e s t to report previous knee i n j u r i e s . In instances where there was previous knee surgery, the scars would indicate such occurrences. However, previous sprains or s t r a i n s are dependent upon a patient's memory, or the memory of the attending physician. For these reasons the i n i t i a l model of mul t i v a r i a t e analysis does not include previous h i s t o r y . However, further equations which do d i f f e r e n t i a t e between those patients who had previous h i s t o r i e s and those who did not are included. 5, Threats to External V a l i d i t y The population studied was a t o t a l sampling of cases from the Lower Mainland who underwent meniscectomy i n 1976 and 1977. Although t o t a l sampling eliminates biases i n t e r n a l to the study, t h i s method of sampling does not eliminate biases that r e s u l t from attempts to generalize these findings to a l l cases treated at the C l i n i c or elsewhere. F i r s t the findings of t h i s study remain v a l i d f o r meniscectomy cases from the Lower Mainland i n 1976 and 1977, but i t i s not known i f they can be genera-l i z e d to other years. In addition, the sample of meniscectomy patients i s used i n t h i s study as a tracer for the t o t a l WCB population undergoing r e h a b i l i t a t i o n at the C l i n i c or elsewhere. However, as w i l l be discussed * For the contents of t h i s section, discussion with Dr. Outerbridge i s valued. -47-i n the f i n a l chapter, findings for meniscectomy are not neces s a r i l y I generalizable to other conditions. E . ANALYSIS The method of analysis was a m u l t i f a c t o r analysis of variance, that i s : Return to work i s a function of c<(type of postoperative r e h a b i l i t a t i o n ) + $ (degenerative changes) + $ (preoperative r e h a b i l i t a t i o n ) + A (medial, l a t e r a l or b i l a t e r a l excision) + £(age). Data was computer analyzed using the S t a t i s t i c a l Package for the S o c i a l Sciences (SPSS). Most of the variables are c a t e g o r i c a l rather than continuous. Analysis of variance with c a t e g o r i c a l v a r i a b l e s can only be done with f i v e independent variables using SPSS. It was decided to f i r s t l y determine the s i g n i f i c a n c e of the type of postoperative r e h a b i l i -t a t i o n , degenerative changes, preoperative r e h a b i l i t a t i o n , medial, l a t e r a l or b i l a t e r a l e x c i s i o n , and age, because these were highly relevant, and aside from degenerative changes, were the most r e l i a b l e measurements. However, other models which eliminated those variables found not to be s i g n i f i c a n t and which included latency, income l o s s , previous h i s t o r y , were then added. This model thus was: Return to work i s the function of cK. (latency) and $ (income loss) and ..... £(whatever was found to be s i g n i f i c a n t from the f i r s t model). The models which thus developed are described i n Chapter V - "Findings of the Study - Part 2 " . A model which also included the complete or p a r t i a l e x i c i s o n of the meniscus was also planned. However, for reasons which are described i n Chapter IV "Findings of the Study - Part 1", t h i s model could not be applied. Because very few cases were found to have sedentary occupations, occupation was not taken as a major explanatory v a r i a b l e . In addition, l o g i c suggest that persons involved i n sedentary occupations would return to work sooner than persons whose jobs were more p h y s i c a l l y demanding. Thus, a l l analyses of variance were calculated twice; f i r s t , with a l l cases included, then with cases of sedentary occupations removed to determine i f t h i s resulted i n s i g n i f i c a n t changes i n F scores. Because of the number of variables examined and the i n a b i l i t y to control the number of cases within each category, empty c e l l s occurred i n the analyses of variance. Accordingly, no two-way or higher order i n t e r --48-actions between independent variables could be determined. Chi squared tests of s i g n i f i c a n c e were used extensively to show the differences i n the populations of the C l i n i c , community or non-treatment group. Although multivariance analysis handles the e f f e c t s of the differences on return to work, i t i s i n t e r e s t i n g to determine i f i n fact the populations of the three groups are e s s e n t i a l l y s i m i l a r or d i f f e r e n t . Differences i n population may indi c a t e on what basis patients' treatment i s selected. Significance was measured at the p = .05 l e v e l . FINDINGS OF THE STUDY The findings of t h i s study are presented i n the following two chapters Chapter IV describes the c h a r a c t e r i s t i c s of the study population. Chapter analyzes the e f f e c t s of these c h a r a c t e r i s t i c s on the number of days return to work, with the primary study c h a r a c t e r i s t i c s being the type of post-operative r e h a b i l i t a t i o n . As w e l l , effectiveness i n terms of-the cost and benefits of the d i f f e r e n t r e h a b i l i t a t i o n approaches i s given i n Chapter V, -49-CHAPTER IV FINDINGS OF THE STUDY - PART I: COMPARISON OF STUDY POPULATIONS The findings of t h i s study are reported i n two categories. The f i r s t i s the breakdown of the study populations by the various factors which can a f f e c t outcome. The second i s an examination of the r e l a t i v e e f f e c t s on return to work of these d i f f e r e n t f a c t o r s . Although analysis of variance includes the differences i n study populations i t i s f e l t that showing these differences i n t h i s chapter may provide more information to the reader. Chapter V presents the analysis of return to work as w e l l as the costs and benefits of the d i f f e r e n t approaches. 1, Type of Postoperative R e h a b i l i t a t i o n Table 4.1 shows the numbers of WCB meniscectomy cases receiving C l i n i c therapy, community r e h a b i l i t a t i o n , or no postoperative p h y s i c a l therapy, according to the c l a s s i f i c a t i o n system described i n the previous chapter. Table 4,1 Number of WCB Meniscectomy Patients by Type of Postoperative R e h a b i l i t a t i o n : 1976 and 1977 Number of Location of Treatment Cases % of T o t a l Cases WCB C l i n i c 85 29.8 Community: Hospital Outpatient 61 21.4 Department Private C l i n i c 46 16.1 Community Therapy indicated 3 1.1 but no record of l o c a t i o n Subtotal: 110 38.6 No Physical Therapy 90 31.6 TOTAL: 285 100.0 -50-2. Age The age of each patient was recorded according to a 10-year c l a s s i f i c a t i o n system. Figure 4.1 shows the age d i s t r i b u t i o n of the cases by the type of postoperative r e h a b i l i t a t i o n . Examination of Figure 4.1 shows that the age breakdown for the three types of r e h a b i l i t a t i o n was f a i r l y comparable. The differences are not s t a t i s t i c a l l y s i g n i f i c a n t . 29.9% of the study population was below age 30. 60% of the study population was found to be below age 40. 3. Income Income loss was measured for each case. Losses were recorded i n $200 per month increments (beginning with losses of $100 per month) as shown i n Figure 4,2. Independent operators were c l a s s i f i e d i n a separate category, because t h e i r losses may d i f f e r from those who are not s e l f -employed, Figure 4,2 shows the number of cases i n each income loss category by type of postoperative r e h a b i l i t a t i o n . An examination of Figure 4,2 shows that within c e r t a i n categories of income loss there are some differences i n the postoperative r e h a b i l i t a t i o n populations. For example, 38.9% of the non-treated group l o s t no income on compensation, but only 28.2% of the C l i n i c patients were experiencing no l o s s . 12,7% of community-treated patients experienced losses of greater than $500 per month but less than $700 per month on compensation, as compared to only 6.7% of non-treated p a t i e n t s . However, aggregating a l l categories above a loss of $500 per month, i t i s found that 20.1% of the C l i n i c cases, 19.9% of the community cases, but only 13.2% of the non-treated cases, were l o s i n g more than $500 per month. However, the differences are not s t a t i s t i c a l l y s i g n i f i c a n t . 4. Degenerative Changes i n the Knee Joint Degenerative changes i n the knee were categorized as none, minimal, moderate or severe. The d i s t r i b u t i o n of degenerative changes according to the type of postoperative therapy i s shown i n Figure 4.3. Figure 4.3 reveals that there are differences i n the degree of degenerative changes i n the populations of the C l i n i c , community and non-treated groups. 29.4% of the C l i n i c population had evidence of minimal degenerative changes i n the knee, as compared to 20.0% of the community group, and 14.4% of the non-treated patients. There i s approximately twice -51-Figure 4.1 Age D i s t r i b u t i o n of Postoperative R e h a b i l i t a t i o n Populations, WCB Meniscectomy Cases: 1976 & 1977 rf. u c •=> o M O 20-29 30-39 28.2 27.8 32.9 40-49 50-59 21.2 28.2 1.2 60+ 3.6 2.2 i 5 i — 10 15 i 20 % of Cases 2 5 30 Key a WCB C l i n i c . Community, n = 85 n =110 90 35 No Phy s i c a l Therapy, n To t a l population 285 7.18341 with 10 degrees of freedom 0.7080 40 -52-Figure 4.2 Income Loss D i s t r i b u t i o n of Postoperative R e h a b i l i t a t i o n Populations, WCB Meniscectomy Cases: 1976 & 1977 38.9 $500 but ^ $700 9,4 12.7 6.7 10 20 % of Cases 30 40 ^ $700 but < $900 \ $900 ^ but </$1100 > $1100 Independent Operator 2.4 2.7 I 3.3 1 1.2 2.7 0.0 4.7 0,9 1.1 2.4 0.9 I 2.1 10 i 20 % of Cases - r ~ 30 40 Key H I WCB C l i n i c Population = 85 cases C D Community Population = 110 cases No Ph y s i c a l Therapy Population = 90 cases = 12.8 with 16 degrees of freedom p = 0.69 Figure 4.3 D i s t r i b u t i o n of Postoperative R e h a b i l i t a t i o n Populations by Degree of Degenerative Changes, WCB Meniscectomy Cases 1976 & 1977 58.8 None; 65.5 78.9 to c CO C J > Minimal Moderate Severe 2 0 . 0 4 29.4 11.8 10.0 0.0 4.5 1.1 i 10 1 20 30 ~~r~ 40 50 60 % of Cases Key H i WCB C l i n i c Population EHJ Community Population No Physical Therapy Population 70 80 85 cases 110 cases 90 cases P 14.8 with 6 degrees of freedom 0.02 -54-the incidence of moderate changes i n the C l i n i c and community groups (11,8% and 10,0% respectively) as compared to the non-treated group (5.6%). There ' were no severe changes i n the C l i n i c sample, but 4.5% of the community sample and 1.1% of the non-treated sample were found to have severe changes. However, the numbers i n t h i s category are small. These differences are s i g n i f i c a n t at the p = 0.05 l e v e l . 5. Preoperative R e h a b i l i t a t i o n Eighty-nine patients underwent some form of preoperative r e h a b i l i t a t i o n . Table 4.2 shows the number of cases treated at the various centres preopera-t i v e l y . In three cases the attending physician -mentioned preoperative r e h a b i l i t a t i o n but no record or b i l l f o r services could be found. I t i s assumed that t h i s occurred i n the community, because records from the C l i n i c would have been on f i l e . It i s possible that the therapy re f e r s to home exercise. However, the manner i n which i t was discussed suggests a more formal approach to preoperative r e h a b i l i t a t i o n . Also included i n Table 4.2 i s one case who experienced knee manipulation from a chiropractor preoperatively. It can be noted that most of the movement from preoperative to post-operative therapy i s from therapy to no therapy or v i c e versa. The majority of the patients who began preoperative treatment at the C l i n i c remained at the C l i n i c postoperatively i f they underwent postoperative treatment at a l l . Only f i v e of 37 cases treated preoperatively at the C l i n i c were referred to the community postoperatively. S i m i l a r l y , none of the 39 patients treated preoperatively i n the community was referred postoperatively to the C l i n i c . In order to determine the t o t a l number of cases undergoing r e h a b i l i -t a t i o n preoperatively, the categories of C l i n i c , Community, C l i n i c and Community, and those for whom treatment was indicated but not recorded, were aggregated. The cases who underwent therapy more than one year before operation and the one case manipulated by the chiropractor were aggregated together with those who experienced no r e h a b i l i t a t i o n p r i o r to operation. The c h i r o p r a c t i c treatment was so c l a s s i f i e d because the therapy consisted of one session of manipulation only. Figure 4.4 shows the d i s t r i b u t i o n of the experience of preoperative r e h a b i l i t a t i o n by type of postoperative r e h a b i l i t a t i o n . An average of 70.5% of the cases experienced no formal -55-Table 4.2 Type of Preoperative R e h a b i l i t a t i o n by Type of Postoperative R e h a b i l i t a t i o n Experienced by WCB, Meniscectomy Cases: 1976 & 1977 Type of Postoperative Treatment m _ i r -n Jr •  v T o t a l f o r a l l No P h y s i c a l Preoperative WCB C l i n i c Community Therapy Groups Type of Preoperative Number Number Number Number Re h a b i l i t a t i o n of Cases of Cases % of Cases % of Cases % No Physical Therapy 58 68.2 70 63.6 68 75.6 196 68.8 WCB C l i n i c 25 29.4 5 4.6 7 7.8 37 13.'0 Community 0 0.0 28 25.5 11 12.2 39 13.7 C l i n i c and Community 2 2.4 2 1.8 1 1.1 5 1.7 Community (remote)* 0 0.0 1 0.9 0 0.0 1 0.4 C l i n i c (remote)* 0 0.0 2 1.8 1 1.1 3 1.0 No record but pre- 0 operative r e h a b i l i t a t i o n i s mentioned 0.0 2. 1.8 1 1.1 3 1.0 Chiropractor 0 0.0 0 0.0 1 1.1 1 0.4 TOTAL 85 100.0 110 100.0 90 100.0 285 100.0 * Remote indicates treatment occurred more than one year p r i o r to operation. ** Indicates percentage of type of preoperative r e h a b i l i t a t i o n group within postoperative r e h a b i l i t a t i o n group. -56-Figure 4.4 D i s t r i b u t i o n of Preoperative R e h a b i l i t a t i o n Within Types of Postoperative R e h a b i l i t a t i o n Groups, WCB Meniscectomy Cases: 1976 & 1977 % of Cases 100 90 J, 80 70 H 60 50 404 30 20 104 31.8 68.2 33.6 66.4 22.2 77.8 WCB C l i n i c Community No Ph y s i c a l Therapy TYPE OF POSTOPERATIVE REHABILITATION Key r~~| Preoperative r e h a b i l i t a t i o n UM No preoperative r e h a b i l i t a t i o n 3.408 with 2 degrees of freedom 0.18 -57-r e h a b i l i t a t i o n p r i o r to operation. The difference i n the experiences of preoperative r e h a b i l i t a t i o n for the postoperative r e h a b i l i t a t i o n groups i s s l i g h t l y d i f f e r e n t f or the n o n - r e h a b i l i t a t i o n group as compared to the C l i n i c and community groups, but the two l a t t e r groups are f a i r l y s i m i l a r . The | difference i s not s t a t i s t i c a l l y s i g n i f i c a n t , 6. Latency The period of time from injury to removal of the meniscus ranged from the same day of i n j u r y to eight years. Figure 4.5 shows the cross-tabulation of latency by type of postoperative r e h a b i l i t a t i o n . The three postoperative r e h a b i l i t a t i o n groups show only a 2% difference i n the number of cases whose latency period was within the f i r s t three months (range from 43.5% to 45.5%). However, there i s a difference i n the figures for the f i r s t s i x months. 67% of the C l i n i c cases, 73.6% of the Community cases, and 78.8% of the non-treated cases had t h e i r menisci removed within the f i r s t s i x months a f t e r i n j u r y . The differences are not s t a t i s t i c a l l y s i g n i f i c a n t . 7. Leg There were s l i g h t l y more l e f t leg i n j u r i e s than r i g h t leg i n j u r i e s . Of the 285 cases, 135 were right leg i n j u r i e s and 150 were l e f t leg i n j u r i e s . Because the sidedness i s not a f a c t o r which a f f e c t s outcome, the cross-tabulation for the three types of postoperative r e h a b i l i t a t i o n groups i s not given. 8. Medial, L a t e r a l or B i l a t e r a l Meniscectomy The incidence of medial, l a t e r a l , and b i l a t e r a l meniscectomy i s shown i n Figure 4.6. The percentages of the three postoperative r e h a b i l i t a t i o n groups who underwent medial, l a t e r a l or b i l a t e r a l meniscectomy i s very s i m i l a r . The differences are not s t a t i s t i c a l l y s i g n i f i c a n t . There i s a wide v a r i a t i o n i n the r a t i o of l a t e r a l to medial menis-cectomies i n the l i t e r a t u r e . Appel (1970) reported a r a t i o of l a t e r a l to medial of 1:4,43. Wyn, Parry et a l (1958) reported a r a t i o of 1:2.2, and Tapper and Hoover (1969) reported a r a t i o of 1:5.1. The r a t i o of l a t e r a l to medial i n t h i s study i s 1:6.6. I t i s important to remember that com-p l i c a t e d cases were excluded from t h i s study. Inclusion may have changed Figure 4.5 Latency D i s t r i b u t i o n of Po s t o p e r a t i v e R e h a b i l i t a t i o n P o p u l a t i o n s , WCB Meniscectomy Cases: 1976 & 1977 Latency P e r i o d — — — — — ™ — • — 10.6 1 month 10.9 ^^^^^^^^^^H12,2 ^6 months but •0- year ^ 1 year but ^3 years ^3 years but <5 years ^5 years but ^9 years 22.4 mm 3.5 1.8 1.1 n.o 3 . 6 1.1 5 10 15 — i — 25 20 % of Cases Key M WCB C l i n i c , n = 85 111 Community, n = 110 H No p h y s i c a l therapy, n = 90 2 % = 10.63 w i t h 12 degrees of freedom p = 0.5611 30 — r — 35 -59 Figure 4.6 D i s t r i b u t i o n of Population of Postoperative R e h a b i l i t a t i o n Groups.by Type of Meniscus Removed, WCB Meniscectomy Cases: 1976 & 1977 % of Cases 100-i 9CH n=85 n=110 n=90 80 4 70 60 50 40-4 30-\ 20 1 10 1.2 12.9 85.9 mm 1.8 11.8 86.4 1.1 11.1 37.8 WCB Community No Ph y s i c a l C l i n i c Therapy Type of Postoperative R e h a b i l i t a t i o n Key 1$88 B i l a t e r a l meniscectomy I—I L a t e r a l meniscectomy WM Medial meniscectomy 2 % = 0.365 with 4 degrees of freedom p = 0.99 -60-t h i s r a t i o . 9. Complete or P a r t i a l Meniscectomy Determining whether a complete or p a r t i a l meniscectomy had been performed was d i f f i c u l t i n 152 cases, or 53% of the t o t a l sample. Although the surgeon did not use the term complete or p a r t i a l , i n 65% of these cases the descriptions were extensive and i t was possible to l a b e l the cases as "probable" complete or p a r t i a l meniscectomy. However, i n 57 operative reports the surgeon simply wrote that a meniscectomy was performed " i n the usual fashion", or some equivalent statement, and there was no way of determining the extent from the records. In 25 cases there was no operative report or h o s p i t a l discharge summary from which to gage the extent of removal. Table 4.3 shows the numbers of complete or p a r t i a l meniscectomies f o r the t o t a l population. Because much of the information i s missing, there was no attempt to cross-tabulate the extent of removal of the meniscus by postoperative r e h a b i l i t a t i o n or to include i t i n the m u l t i - v a r i a t e a n a l y s i s . Table 4.3 Numbers and Percentages of WCB Meniscectomy Cases Who Underwent Complete or P a r t i a l Meniscectomy: 1976 & 1977 Extent of Excision Number of Cases Percentage of Total Complete P a r t i a l Probably complete Probably p a r t i a l Report not clear No operative report or discharge summary 107 26 68 3 57 24 285 37.5 9.1 23.8 1.1 20.1 8.4 100.0 10. Previous History of Injury of Same Knee Previous h i s t o r y of knee in j u r y on the same leg was recorded as found i n the records. It i s r e a l i z e d that the accuracy of previous h i s t o r y i s dependent upon the patient's memory and the doctor's d i l i g e n c e i n reporting. -61-Thus, although 83.2% of the cases report no previous h i s t o r y , t h i s figure may possibly be high. However, previous h i s t o r y i s important insofar as i t contributes to degenerative changes within the knee, and t h i s i s recorded separately. Table 4.4 shows the number of cases with previous i n j u r i e s to the knee. Figure 4.7 combines these numbers to show percentages of cases with h i s t o r y of previous meniscectomy or other h i s t o r y . The percentages of cases with previous h i s t o r i e s i s higher i n the C l i n i c than i n the community or non—treated group. This may be due to better reporting. The difference i s not s t a t i s t i c a l l y s i g n i f i c a n t . 11. Occupation Occupation was c l a s s i f i e d as sedentary or non-sedentary. Sedentary positions were considered to be those of c l e r k s , managers, salesmen, typesetters, or other s i m i l a r occupations. Only 21 people were found to have sedentary positions - 8 C l i n i c patients (9.4% of the C l i n i c population), 3 community patients (2.7% of the community population), and 10 non-treated 2 patients (11,1% of the non^-treated population). ^ £ = 5.838 with two degrees of freedom, p = 0.054, which i s s t a t i s t i c a l l y s i g n i f i c a n t . 12. Posterior I n c i s i o n The presence of a second p o s t e r i o r i n c i s i o n could not be determined without an operative report. Thus, f o r the 255 cases who had operative reports, Figure 4.8 shows the percentages of cases within the study popula-t i o n who had p o s t e r i o r i n c i s i o n s . There was three times the incidence of po s t e r i o r i n c i s i o n s i n the community than i n the C l i n i c , and f i v e times the incidence i n the community than i n the non-treated group. The difference i s s t a t i s t i c a l l y s i g n i f i c a n t . 13. Physician R e f e r r a l Patterns The 285 cases studied were d i s t r i b u t e d among 52 surgeons. The range of cases per surgeon was from one case to 23 cases. Table 4.5 shows the breakdown of r e h a b i l i t a t i o n r e f e r r a l s of each surgeon by h i s l o c a t i o n i n the Lower Mainland. (In 1976 and 1977 the WCB C l i n i c was located i n Vancouver.) Because of the small number of cases which many surgeons handled, i t i s d i f f i c u l t to determine the reasons behind r e f e r r a l . The o v e r a l l impression i s that most physicians appear f a i r l y consistent i n t h e i r -62-Table 4.4 Previous History of Injury to the Same Leg by Type of Postoperative R e h a b i l i t a t i o n Experienced by WCB Meniscectomy Cases: 1976 & 1977 WCB C l i n i c Community No previous h i s t o r y Previous removal of other meniscus Previous removal of same meniscus Recent sprain or s t r a i n of knee Remote sprains or st r a i n s of knee Previous arthrotomy Remote meniscal tear, not removed Old fracture with no remaining problems Old tear medial c o l l a t e r a l ligament with no remaining problems Miscellaneous: i ) C a r t i l a g e damage of the knee i i ) Crush i n j u r y of the knee i i i ) P r e p a t e l l a r b u r s i t i s i v ) Tendon transplant and ligamentous repair of ankle Number of Cases 65 3 0 3 1 3 0 1 %* 76.5 3.5 0.0 3.5 9.4 1.2 3.5 0.0 1.2 1.2 Number of Cases 95 2 0 3 6 0 1 1 0 % 86,4 1.8 0.0 2.7 5.5 0.0 0.9 0.9 0.0 No Physical Therapy Number of Cases % 76 4 1 3 2 0 1 1 0 84.5 4.5 1.1 3.3 2.2 0.0 1.1 1.1 0.0 2.2 TOTALS: 85 100.0 110 100.0 90 100.0 * Percent of category of previous h i s t o r y within type of postoperative r e h a b i l i t a t i o n . -63-u 0 3 O •H > u Figure 4.7 D i s t r i b u t i o n of Postoperative R e h a b i l i t a t i o n Populations by Previous History of the Same Leg, WCB Meniscectomy Cases: 1976 & 1977 No Previous History Previous Meniscectomy Other History 20.0 11.8 10.0 1 1 1 1 1 1 1 1 r — 10 20 30 40 50 60 70 80 90 % of cases Key m WCB C l i n i c Population = 85 cases Tml Community Population = 110 cases No P h y s i c a l Therapy Population = 90 cases 2 = 6.23 with 4 degrees of freedom p = 0,1826 -64-P o s t e r i o r I n c i s i o n 8.8 5.3 10 27.0 To ~30~ 40 50 60 % of Cases Key ffl C l i n i c Community No Ph y s i c a l Therapy T o t a l X , 2 To" 80 90 100 n = 75 n = 80 n = 100 = 255 - 19,34 with 2 degrees of freedom = 0.0001 - 6 5 -Table 4 . 5 Postoperative R e h a b i l i t a t i o n R e f e r r a l Patterns of Surgeons for Postoperative WCB Meniscectomy Cases: 1976 & 1977 Location of Surgeon Physician Number WCB C l i n i c Community No Physical Therapy Total I. Vancouver 1 1 0 1 2 2 1 0 0 1 3 1 0 0 1 4 2 0 0 2 5 1 0 9 10 6 1 0 2 3 7 2 1 0 3 8 1 1 0 2 9 2 2 6 10 10 1 0 0 1 1 1 . 0 0 4 4 12 0 0 6 6 13 1 0 0 1 14 1 0 ' 7 8 15 8 0 0 8 16 3 0 1 4 17 6 0 0 6 18 4 2 0 6 19 o 1 0 1 20 1 0 1 2 21 3 0 1 4 22 0 1 4 5 23 5 2 1 8 24 1 0 4 5 25 0 0 2 2 Subtotal . 4 6 10 49 105 I I . Burnaby 26 6 2 0 8 27 17 4 0 21 28 1 1 0 2 Subtotal 24 7 0 31 \ -66-Table 4.5 ( continued ) Physician WCB No Physical Location of Surgeon Number C l i n i c Community Therapy Total I I I . Richmond 29 2 0 1 ! 3 30 0 0 1 1 Subtotal 2 0 2 4 IV, North Vancouver 31 6 1 0 7 32 1 1 0 2 33 2 7 2 11 34 1 2 1 4 35 1 1 0 2 Subtotal 11 12 3 26 V. Surrey 36 0 9 2 11 37 0 16 0 16 New Westminster 38 0 3 3 6 39 0 7 16 23 40 0 2 2 4 41 0 1 0 1 42 0 1 4 5 43 0 3 0 3 44 0 2 0 2 45 2 10 1 13 46 0 1 0 1 Delta 47 0 4 0 4 48 0 6 1 7 Chilliwack 49 0 7 1 8 50 0 1 0 1 Maple Ridge 51 0 8 5 13 Subtotal 2 81 35 118 Vancouver Island* 52 0 0 1 1 TOTALS: 85 110 90 285 * One Lower Mainland patient p ref e r r e d a Vancouver Island surgeon. However, the postoperative course and followup occurred i n the Lower Mainland. -67-r e f e r r a l patterns. Surgeons outside Vancouver, North Vancouver or Burnaby tend not to r e f e r patients to the WCB C l i n i c but prefer community r e f e r r a l i f postoperative r e h a b i l i t a t i o n i s ordered. The "no postoperative r e h a b i l i -t a t i o n " approach appears to be more common among Vancouver surgeons than others, 14. Time Intensity of Postoperative R e h a b i l i t a t i o n Among Community Patients Table 4.6 shows the time i n t e n s i t y of r e h a b i l i t a t i o n which community patients received. The three cases for which community therapy was mentioned but no b i l l or record of where t h i s therapy occurred could be found, were excluded from t h i s table. Table 4.6 Time Intensity of Postoperative R e h a b i l i t a t i o n f o r WCB Meniscectomy Cases Treated i n the Community: 1976 & 1977 Time Intensity Number of Cases Percentage of Total Intensive treatment 37 34.5 (4 or 5 times per week) Non-intensive treatment 68 63.6 (1 to 3 times per week) I n i t i a l intensive period, 2 1.9 followed by non-intensive treatment 107 100.0 -68-SUMMARY i The three postoperative r e h a b i l i t a t i o n groups d i f f e r s i g n i f i c a n t l y i n three c h a r a c t e r i s t i c s : the frequency of degenerative changes i n the knee, occupation, and the presence of a po s t e r i o r i n c i s i o n . A greater percentage of WCB C l i n i c patients were found to have degenerative changes of the knee than the other populations. The lowest incidence of knee degeneration was found i n the non-treatment group. However, there were no cases of patients with severe degeneration i n the WCB C l i n i c group. While the percentages of cases with sedentary occupations i s s l i g h t l y higher i n the non^-treated group than i n the WCB C l i n i c , there were very few sedentary cases i n the Community. The incidence of p o s t e r i o r i n c i s i o n s was much greater i n the Community than i n the other populations. The e f f e c t s of these v a r i a b l e s , as well as the e f f e c t s of other variables whose d i s t r i b u t i o n s were not found to d i f f e r s i g n i f i c a n t l y , are co n t r o l l e d through m u l t i v a r i a t e analysis of the variance i n the number of days return to work. Surgeons were found to d i f f e r i n t h e i r r e h a b i l i t a t i o n r e f e r r a l patterns. However, no attempt w i l l be made to con t r o l for these e f f e c t s of the r e f e r r i n g physician, due to the great number of physicians involved, and due to the fac t that i n d i v i d u a l physicians were found to be f a i r l y consistent i n t h e i r r e f e r r a l patterns. Thus, the e f f e c t s of the surgeon are confounded by the type of postoperative r e h a b i l i t a t i o n . The following chapter presents the analysis of variance i n the number -of days return to work of the postoperative meniscectomy cases, as well as the costs and benefits of the d i f f e r e n t approaches. -69-CHAPTER V FINDINGS OF THE STUDY - PART I I : ANALYSTS OF RETURN TO WORK A. OVERVIEW Return to work was recorded as the number of calendar days from operation to return to work. Table 5.1 shows the mean, median, ranges and standard deviations of the number of days before return to work for the WCB C l i n i c , Community and No Physical Therapy populations of t h i s study. For the 285 cases, return to work var i e d from 7 days to 643 days post-operative with a mean of 90.6 days and a median of 77.8 days. Table 5.1 Number of Days Before Return to Work by Type of Postoperative R e h a b i l i t a t i o n Group, WCB Meniscectomy Cases: 1976 & 1977 R e h a b i l i t a t i o n Population Number of Days Return to Work Mean Median Standard Deviation Range of Return to Work Minimum Maximum WCB C l i n i c Community No Physical Therapy 116,7 102.7 89.4 74.5 67.5 60.0 80.9 53.5 33.5 22 643 14 410 7 246 Total Population 90.6 77.8 61,3 643 The mean and median days return to work was the lowest f o r the non-treated group and the highest for the C l i n i c group. Figure 5,1 shows the comparison of the r e l a t i v e frequencies of return to work time for the three groups, Return to work i s measured i n weeks on th i s graph to allow for aggregation. Figure 5.2 shows the same comparison measured i n cumulative frequencies. 98.6% of a l l cases returned to work by 246 days (36 weeks.) However, four cases returned to work l a t e r than t h i s . For these o u t l i e r s return to work was measured as 305, 362, 410 and 643 days r e s p e c t i v e l y . Because these F i g u r e 5 . 1 C o m p a r i s o n o f R e t u r n t o W o r k P o s t m e n i s c e c t o m y o f WCB C l i n i c , C o m m u n i t y and No P h y s i c a l T h e r a p y P a t i e n t s : 1 9 7 6 & 1 9 7 7 No P h y s i c a l T h e r a p y Number o f Weeks B e f o r e R e t u r n t o W o r k I O 1 Figure 5.2 Comparison of Cumulative Frequencies f o r Return to Work Post Meniscectomy of WCB C l i n i c , Community and No Physical Therapy Patients, WCB Meniscectomy Cases: 1976 & 1977 Percent Cumulative Frequency Number of Weeks Return to Work Key __ WCB C l i n i c __ Community I H No Ph y s i c a l Therapy Population Population Population -72-cases are extreme, they were removed from a l l further analysis of return to work. It i s i n t e r e s t i n g to note that three of the o u t l i e r s were WCB C l i n i c patients and one, the case which remained o f f work 410 days, was a Community patient. Two of the o u t l i e r s , the ones measuring 362 and 410 days, are the two cases of medial meniscectomy who also underwent l a t e r a l arthrotomies to investigate the other meniscus. Because t h i s i s a sample of only two cases, no conclusions can be drawn. Removing the o u t l i e r s from the comparison of return to work changes the s t a t i s t i c s of return to work. Table 5.2 shows that with cases over 300 days RTW removed from the a n a l y s i s , the mean return to work for the WCB C l i n i c , Community and Non-Treated R e h a b i l i t a t i o n populations are 105.0, 86.4 and 67.5 days re s p e c t i v e l y . These means (minus the o u t l i e r s ) are the basis f or the remainder of the a n a l y s i s . Removing the o u t l i e r s resulted i n 281 cases remaining to be analyzed: 82 WCB C l i n i c cases, 109 Community cases and 90 Non-treated cases. Table 5.2 Adjusted* Summary of Measures of Return to Work by Type of Postoperative R e h a b i l i t a t i o n , WCB Meniscectomy Cases: 1976 & 1977 Range of Return to Work Re h a b i l i t a t i o n Standard Population Mean Median Deviation Minimum Maximum WCB C l i n i c 105.0 101.0 45.3 22 243 Community 86.4 74.3 43.9 14 221 No Physical 67.5 60.0 33.5 7 246 Therapy To t a l Population 85.8 77.2 43.7 7 246 Excludes cases above 300 Days Return to Work B s FACTORS. AFFECTING 'RETURN: TO WORK. -73-1, The E f f e c t s of the Type of Postoperative R e h a b i l i t a t i o n , Experience of Preoperative R e h a b i l i t a t i o n , Age, Meniscus Excised, and Degenerative Changes on Return to Work Times The e f f e c t s of the type of postoperative r e h a b i l i t a t i o n , experience of preoperative r e h a b i l i t a t i o n , age, meniscus excised and degenerative changes of the knee on return to work time are shown i n Table 5.3. For the purpose of t h i s a n a l y s i s , age groups were analyzed i n three categories (less than 30 years of age, 30 to 49 years of age, and 50 years and above). As w e l l , preoperative r e h a b i l i t a t i o n was analyzed i n two categories - those who received preoperative r e h a b i l i t a t i o n and those who did not. The only factors which were found to be s i g n i f i c a n t were the type of postoperative r e h a b i l i t a -t i o n the patient received, and whether or not he experienced preoperative p h y s i c a l therapy. Neither age, degree of degenerative changes of the knee, nor the meniscus excised were found to be s i g n i f i c a n t . However, a s u r p r i s i n g f i n d i n g i s that preoperative r e h a b i l i t a t i o n resulted i n a longer return to work time f o r those patients who experienced i t as compared to those who did not. Thus, the analysis of variance was recalculated, but i n t h i s instance preoperative r e h a b i l i t a t i o n was analyzed i n four categories: no preoperative treatment, WCB C l i n i c treatment, Community treatment, and both WCB C l i n i c and Community treatment. The independent v a r i a b l e of the meniscus excised was removed from the analysis because the e f f e c t s of medial, l a t e r a l , or b i l a t e r a l meniscectomy were found to be very i n s i g n i f i c a n t (p =0.86). Table 5.4 shows that with t h i s method the type of preoperative and postoperative r e h a b i l i t a t i o n are found to s i g n i f i c a n t l y a f f e c t return to work for a l l cases and for non-sedentary cases only. The e f f e c t s of age and degree of degenerative changes remain i n s i g n i f i c a n t . The M u l t i p l e C l a s s i f i c a t i o n Analysis found i n Table 5.4 reveals that patients r e c e i v i n g no preoperative r e h a b i l i t a t i o n did co n s i s t e n t l y better than those who experienced preoperative r e h a b i l i t a t i o n , even when adjusting for other f a c t o r s . For a l l cases those r e h a b i l i t a t e d preoperatively at the WCB C l i n i c returned to work at a l a t e r date than those r e h a b i l i t a t e d preoperatively i n the Community, although adjusting the deviation to allow f o r the e f f e c t s of the other variables reduces the d i f f e r e n c e . However, for non-sedentary cases only, although the unadjusted mean return to work time i s greater for patients preoperatively treated i n the WCB C l i n i c as compared to the Community, adjustment reverses t h i s comparison to favour the C l i n i c s l i g h t l y . Patients preoperatively -74-Table 5.3 Va r i a t i o n s i n the Number of Days Return to Work Due to Type of Postoperative R e h a b i l i t a t i o n , Experience of Preoperative R e h a b i l i t a t i o n , Age, Meniscus Excised and Degenerative Changes of the Knee, WCB Meniscectomy Cases: 1976 & 1977 Source of V a r i a t i o n F Score S i g n i f i c a n c e of F 1. Type of Postoperative R e h a b i l i t a t i o n 15.142 0.000 2. Experience of Preoperative 7.558 0.006 R e h a b i l i t a t i o n 3. Age 1.432 0.241 4. Meniscus excised 0,150 0.861 5. Degenerative changes 1.601 0.190 MULTIPLE CLASSIFICATION ANALYSIS Number of Cases = 281 Grand Mean = 85.79 days Variable and Category Number of Cases II. I I I . Type of Postoperative R e h a b i l i t a t i o n  WCB C l i n i c 82 Community 109 None 90 Experience of Pre^-Operative R e h a b i l i t a t i o n None 199 Received Preoperative 82 R e h a b i l i t a t i o n Age Less than 30 years 85 30 to 49 years 148 50 years plus 48 IV. Meniscus Excised Medial 243 L a t e r a l 34 B i l a t e r a l 4 V. Degenerative Changes of the Knee  None 191 Minimal 58 Moderate 26 Severe 6 Unadjusted Deviation 19.17 0.65 -18.26 - 5.23 12.70 8,00 4.04 1,71 0.64 3.64 7.79 -4.80 16.24 0.59 - 6.96 Eta 0.34 0.19 0.12 0.04 Adjusted Deviation 18.49 - 0.23 -16.57 - 4.32 10.48 6.56 2.80 2.90 0.52 3.16 4.91 -1.96 10.19 - 6.47 - 7.97 Beta 0.31 0.15 0.10 0.03 0.19 0.12 M u l t i p l e R Squared 0.169 -75-Table 5.4 Vari a t i o n s i n the Number of Days Return to Work Due to the Type of Postoperative R e h a b i l i t a t i o n Type of Preoperative R e h a b i l i t a t i o n , Age, and Degree of Degenerative Changes of the Knee WCB Meniscectomy Cases: 1976 & 1977 ' Source of V a r i a t i o n F Score I. Type of Postoperative 14.243 R e h a b i l i t a t i o n I I . Type of Preoperative 6.074 R e h a b i l i t a t i o n I I I . Age 1.461 IV. Degenerative Changes 1.550 ALL CASES Si g n i f i c a n c e of F 0.000 0.001 0.234 0.202 NON-SEDENTARY CASES ONLY F Score, S i g n i f i c a n c e of F 13.028 3.139 0.749 1.637 0.000 0.026 0.588 0.181 Number of Cases = Grand Mean Variable and Category I. 281 85.79 days Mean No.of Days Un-Number Adjusted of Cases Deviation MULTIPLE CLASSIFICATION ANALYSIS 260 II, Type of Postoperative R e h a b i l i t a t i o n  WCB C l i n i c , 82 Community 109 None 90 Type of Preoperative R e h a b i l i t a t i o n  None 199 WCB C l i n i c 36 Community 42 WCB C l i n i c and Community 4 Less than 30 years 85 30 to 49 years 148 50 years or older 48 IV. Degenerative Changes None 191 Minimal 58 Moderate 26 Severe 6 19.17 0.65 -18.26 Mean No. of Days Adj usted Eta Deviation 18.13 - 0.06 -16.44 0.34 III. -5.23 19.96 0.64 73.96 8.00 4.04 1.71 -4.80 16.24 0.59 - 6.96 0.28 0.12 - 4.35 9.30 5.76 72.39 6.52 2.49 3.87 - 2.08 10.00 - 5.57 - 6.49 0.19 87.23 days Mean No.of Days Un-Number Adjusted Beta of Cases Deviation Mean No. of Days Adj usted Eta Deviation 74 106 • 80 17.56 0.46 -16.86 0.31 18.18 - 0.97 -15.53 0.32 0.23 0.10 185 33 39 3 77 137 46 171 57 26 6 - 3.87 13.55 2.23 60.77 7.62 3.63 1.96 - 4.98 16.20 - 0.85 - 8.40 0.21 0.12 M u l t i p l e R Squared 0.12 0.199 - 3.09 3.11 7.04 65.00 6.08 2.41 3.01 - 2.33 10.69 - 6.49 - 7.14 0.21 Beta 0.31 0.197 0.09 0.14 0.171 -76-treated i n both the C l i n i c and the Community (only four cases) returned to work on the average much l a t e r than any other cases. To investigate possible i n t e r a c t i o n s between the type of preoperative and postoperative r e h a b i l i t a t i o n , a breakdown analysis of t h e i r combined e f f e c t on return to work was performed. The r e s u l t s are shown i n Table 5.5. It can be seen that patients who experienced neither preoperative nor postoperative r e h a b i l i t a t i o n returned to work the quickest, with a mean of 63 days. The longest return to work time was experienced by the one case r e h a b i l i t a t e d preoperatively i n both the C l i n i c and the Community, but who received no postoperative r e h a b i l i t a t i o n , and the next longest return to work by the one case who was treated preoperatively i n both the C l i n i c and the Community, but treated postoperatively i n only the C l i n i c . Because these represent only two cases, i t cannot be determined i f t h i s was due to the e f f e c t s of the combined areas of treatment, or i f these were i d e n t i f i e d preoperatively as problem cases which then required treatment i n both l o c a l e s . Excluding the cases preoperatively treated i n both the C l i n i c and the Community, the highest means for return to work within each of the three types of postoperative r e h a b i l i t a t i o n groups was for the subgroup preoperatively treated i n the WCB C l i n i c . Excluding sedentary cases, as shown i n Table 5.6, r e s u l t s i n only minor changes i n these findings. Patients i n the non-treated and Community r e h a b i l i t a t e d postoperative groups continue to do worse i f preoperatively treated i n the WCB C l i n i c , a l b e i t the numbers are small. There i s v i r t u a l l y no differ e n c e i n the r e s u l t s for C l i n i c patients who were preoperatively treated i n the C l i n i c as compared to those who were not preoperatively treated at a l l . (No C l i n i c patient was preoperatively treated i n the Community.) The degree of degenerative changes was not found to be s i g n i f i c a n t , but the multiple c l a s s i f i c a t i o n analysis i n Table 5.4 reveals an unusual pattern. Patients with minimal degenerative changes took the longest to return to work, but patients with severe changes, a l b e i t only s i x cases, returned to work the quickest. Adjusting the deviation to allow for other e f f e c t s resulted i n patients with moderate and severe degenerative changes returning to work sooner than those with no degenerative changes. However, th i s can perhaps be expl?ined by the fact that there were no patients with severe degenerative changes treated i n the C l i n i c . Because there was a higher incidence of minimal degenerative changes i n WCB C l i n i c patients and because those with minimal changes did worse than the others, i t was decided as a f i n a l check to r e c a l c u l a t e the analysis Table 5.5 Mean Number of Days Return to Work by Type of Preoperative and Postoperative R e h a b i l i t a t i o n , WCB Meniscectomy Cases: 1976 & 1977 Preoperative R e h a b i l i t a t i o n WCB C l i n i c & None C l i n i c Community Community Tot a l None n* = 70 n = 7 n = 12 n = l n = 9 0 x** = 63.0 x = 77.3 x = 7 3 . 6 x - 246.0 x = 67.5 a o % WCB C l i n i c n = 5 7 n = 2 4 n = 0 n = 1 n = 8 2 +J •H 3 x" = 100.9 x = 110.9 x = 195.0 x = 105.0 (fl & •H Community n = 7 2 n = 5 n = 3 0 n = 2 n = 109 cS u g- x 81.6 x = 121.0 x = 91.6 x = 99.0 x = 86.4 4-1 cn o PA Total n = 199 n = 36 n = 42 n = 4 n = 281 x = 80.6 x = 105.5 x = 8 6 . 4 x = 159.8 x = 85.8 *n = number of cases mean number of days return to work -78-i Table 5.6 Mean Number of Days Return to Work by Type of Preoperative R e h a b i l i t a t i o n and Postoperative R e h a b i l i t a t i o n , Non-Sedentary Cases Only, WCB Meniscectomy Cases: 1976 & 1977 Preoperative R e h a b i l i t a t i o n WCB C l i n i c & None C l i n i c Community Community Total * None n = 6 3 n = 7 n = 9 n = 1 n = 8 0 __** _ _ _ _ _ _ x = 65.10 x = 77.29 x = 82.44 x = 246.0 x = 70.38 c o •H 2 WCB C l i n i c n = 5 3 n = 21 n = 0 n = 0 n =. 74 • H •g x = 105.19 x = 103.81 x = 104.80 Xi CD Pi > n = 6 9 n = 5 n = 3 0 n = 2 n = 106 to Community o x = 83.28 x = 121.00 x = 91.57 x = 99.0 x = 87.70 w o T o t a l n = 185 n = 33 n = 39 n = 3 n = 260 x = 83.36 x = 100.79 x = 89.46 x = 148.0 x = 87.23 * n = number of cases ** x = mean number of days return to work -79-of variance, eliminating a l l cases of degenerative changes and a l l sedentary occupations. This resulted i n 171 cases remaining to be analyzed. Both | the e f f e c t s of postoperative and preoperative r e h a b i l i t a t i o n remained s i g n i f i c a n t , while age remained i n s i g n i f i c a n t . For these non-sedentary cases and cases of no degenerative changes of the knee, the mean return to work time i n WCB C l i n i c cases was 101.72 days, for Community cases 83.69 days and non-treated cases 67.26 days. The d e t a i l s of t h i s analysis of variance are found i n Table 5.7. 2. The E f f e c t s of Income, Latency and Previous History of the Knee The analysis of variance i n the number of days return to work was re c a l c u l a t e d , adding the factors of income, latency period and previous h i s t o r y of the knee to the two variables previously determined to be s i g n i f i c a n t (type of postoperative r e h a b i l i t a t i o n and type of preoperative r e h a b i l i t a t i o n ) , None of the new variables studied was found to be s i g n i f i -cant , whether a l l cases or sedentary cases only were analyzed. Table 5.8 shows these r e s u l t s and Table 5.9 the r e s u l t s of the same analysis for non-sedentary cases with no degenerative changes of the knee. Although the latency period was not found to be s i g n i f i c a n t , i t i s i n t e r e s t i n g to note that whether adjusted or not adjusted for other e f f e c t s , those with a latency period of less than one month returned to work the e a r l i e s t , and those with a latency period of one year returned to work at a l a t e r date than the other cases. However, those with latency periods of between s i x months and one year returned to work e a r l i e r than those with latency periods between three and s i x months. Thus i t i s d i f f i c u l t to determine a pattern. Income loss was not found to be s i g n i f i c a n t i n any of the analyses, nor could a l o g i c a l pattern be determined. 3. The E f f e c t of Posterior I n c i s i o n For the 252 cases for which operative reports were a v a i l a b l e , the e f f e c t of p o s t e r i o r i n c i s i o n upon return to work was found not to be s i g n i -f i c a n t . Table 5.10 shows the r e s u l t s of t h i s analysis of variance for the non-sedentary subset of these cases. Although not s t a t i s t i c a l l y s i g n i f i c a n t , the presence of a p o s t e r i o r i n c i s i o n resulted i n a higher mean return to work f o r the population which experienced i t , a l b e i t the numbers of cases are r e l a t i v e l y small. (Only 15% of a l l cases and 20% of non-sedentary cases received p o s t e r i o r i n c i s i o n s . ) Analyzing the variance for those cases -80-Table 5.7 Variations i n the Number of Days Return to Work Due to Type of Postoperative R e h a b i l i t a t i o n , Type of Preoperative R e h a b i l i t a t i o n and age, for WCB Meniscectomy Cases with Non-sedentary Occupations and No Degenerative Changes of the Knee: 1976 & 1977 Source of V a r i a t i o n F Score Significance of F 1. Type of Postoperative R e h a b i l i t a t i o n 2. Type of Preoperative R e h a b i l i t a t i o n 3 • Age 11.441 8.350 1.522 0.000 0.000 0.221 MULTIPLE CLASSIFICATION ANALYSIS Number of Cases = 171 Grand Mean = 82,26 Variable and Category [. Type of Postoperative R e h a b i l i t a t i o n  WCB C l i n i c Community None Number of Cases 42 68 61 Number of Days Un-adjusted Deviation 19.46 1.43 -15.00 Eta Number of Days Adjusted Deviation Beta 21.17 - 0.09 -14.47 0.34 0.35 I I . Type of Preoperative R e h a b i l i t a t i o n  None 128 WCB C l i n i c 17 Community 24 C l i n i c and Community 2 -5.60 21.15 6.87 96.24 -5.34 10.09 12.64 104.18 0.34 0.34 I I I . Age Less than 30 years 30 to 49 years 50 years plus 68 91 12 4.42 4.30 7.59 0.12 5.61 4.30 0.84 0.12 M u l t i p l e R Squared 0.249 -81-T a b l e 5 . 8 V a r i a t i o n s i n t h e N u m b e r o f D a y s R e t u r n t o W o r k b y T y p e o f P o s t o p e r a t i v e R e h a b i l i t a t i o n , T y p e o f P r e o p e r a t i v e R e h a b i l i t a t i o n , P r e v i o u s H i B t o r y o f t h e K n e e , L a t e n c y P e r i o d a n d i n c o m e L o s s , WCB M e n i s c e c t o m y C a s e s : 1 9 7 6 & 1 9 7 7 S o u r c e o f V a r i a t i o n F S c o r e I. T y p e o f P o s t o p e r a t i v e 1 5 . 3 9 6 R e h a b i l i t a t i o n I I . T y p e o f P r e o p e r a t i v e 5 . 1 4 5 R e h a b i l i t a t i o n I I I . P r e v i o u s H i s t o r y 0 . 8 5 4 I V . L a t e n c y P e r i o d 1 . 3 4 4 V . I n c o m e L o s s 0 . 3 6 7 A L L C A S E S S i g n i f i c a n c e o f F 0 . 0 0 0 0 . 0 0 2 0 . 4 2 7 0 . 2 5 4 0 . 8 7 N O N - S E D E N T A R Y C A S E S ONLY F S c o r e S i g n i f i c a n c e o f F 1 4 . 4 5 6 0 . 0 0 0 2 . 7 7 4 0 . 0 4 2 0 . 4 0 2 0 . 6 6 9 1 . 8 3 9 0 . 1 2 2 0 . 7 2 9 0 . 6 0 2 Number o f C a s e s • G r a n d M e a n ™ 2 8 1 8 5 . 7 9 d a y s M e a n N o . o f D a y s U n -Number A d j u s t e d o f C a s e s D e v i a t i o n M U L T I P L E C L A S S I F I C A T I O N A N A L Y S I S 260 I. T y p e o f P o s t o p e r a t i v e R e h a b i l i t a t i o n  WCB C l i n i c 82 C o m m u n i t y 109 None 9 0 I I . T y p e o f P r e o p e r a t i v e R e h a b i l i t a t i o n  None 199 WCB C l i n i c 36 C o m m u n i t y 4 2 WCB C l i n i c a n d C o m m u n i t y 4 1 9 . 1 7 0 . 6 5 - 1 8 . 2 6 - 5 . 2 3 1 9 . 9 6 0 . 6 4 7 3 . 9 6 M e a n N o . o f D a y s A d j u s t e d E t a D e v i a t i o n 1 9 . 2 5 0 . 3 2 - 1 7 . 1 6 0 . 3 4 - 4 . 0 4 9 . 8 6 4 . 0 9 6 9 . 3 5 8 7 . 2 3 d a y s M e a n N o . o f D a y s U n -N u m b e r A d j u s t e d B e t a o f C a s e s D e v i a t i o n 0 . 3 3 74 106 80 185 33 39 3 1 7 . 5 6 0 . 4 6 - 1 6 . 8 6 - 3 . 8 7 1 3 . 5 5 2 . 2 3 6 0 . 7 7 M e a n N o . o f D a y s A d j u s t e d E t a D e v i a t i o n 1 9 . 5 8 - 1 . 1 4 - 1 6 . 6 1 0 . 3 2 - 2 . 9 9 4 . 1 6 6 . 1 8 5 8 . 3 0 B e t a 0 . 3 3 0 . 2 8 0 . 2 2 0 . 2 1 0 . 1 7 I I I , P r e v i o u s H i s t o r y No p r e v i o u s h i s t o r y P r e v i o u s m e n i s c e c t o m y O t h e r h i s t o r y I V . L a t e n c y P e r i o d L e s s t h a n 1 1 m o n t h 3 m o n t h s 6 m o n t h s 1 y e a r m o n t h 3 m o n t h s 6 m o n t h s 1 y e a r I ncome L o s s P e r M o n t h No l o s s $ 1 0 0 $ 1 0 0 b u t $ 3 0 0 S 3 0 0 b u t S 5 0 0 $ 5 0 0 I n d e p e n d e n t O p e r a t o r M u l t i p l e R S q u a r e d 232 10 39 31 93 82 44 31 94 25 64 47 46 5 0 . 4 6 1 . 2 1 3 . 0 7 - 1 2 . 1 4 - 2 . 2 4 1 . 3 9 - 1 . 8 4 1 7 . 7 9 5 . 7 6 3 . 0 3 6 . 7 3 3 . 4 7 1 . 1 9 6 . 1 9 0 . 0 3 0 . 1 7 0 . 1 2 1 . 2 6 2 . 3 4 8 . 0 8 - 6 . 8 8 - 1 . 8 2 2 . 4 0 - 5 . 2 3 1 3 . 4 2 54 11 91 25 3 3 1 . 1 7 0 . 0 7 0 . 1 3 0 . 0 8 0 . 1 9 9 217 10 30 28 87 79 37 29 8 3 24 63 43 4 3 4 0 . 0 4 0 . 2 3 0 . 3 1 - 1 0 . 0 2 - 2 . 0 7 0 . 6 6 - 4 . 9 4 2 0 . 3 9 4 . 0 5 2 . 6 1 5 . 5 6 5 . 8 1 5 . 3 0 6 . 7 7 0 . 0 0 0 . 1 9 0 . 8 9 0 . 4 9 - 5 . 9 7 - 6 . 8 0 - 2 . 6 9 2 . 6 7 - 6 . 6 9 1 6 . 1 7 - 1 . 2 3 - 2 . 2 0 2 . 9 7 5 . 6 5 - 7 . 8 0 1 4 . 9 4 0 . 1 2 0 . 0 5 0 . 1 6 0 . 1 2 0 . 1 7 9 T a b l e 5 . 9 V a r i a t i o n s l n t h e Number o f D a y s R e t u r n t o W o r k Due t o T y p e o f P o s t o p e r a t i v e R e h a b i l i t a t i o n , T y p e o f P r e o p e r a t i v e R e h a b i l i t a t i o n , P r e v i o u s H i s t o r y o f t h e K n e e , L a t e n c y P e r i o d a n d I n c o m e o f WCB M e n i s c e c t o m y C a s e s w i t h N o n - s e d e n t a r y O c c u p a t i o n s a n d No D e g e n e r a t i v e C h a n g e s o f t h e K n e e : 1 9 7 6 I 1977 S o u r c e o f V a r i a t i o n T S c o r e I. T y p e o f P o s t o p e r a t i v e R e h a b i l i t a t i o n 9 . 7 5 8 I I . T y p e o f P r e o p e r a t i v e R e h a b i l i t a t i o n 6 . 4 5 4 I I I . P r e v i o u s H i s t o r y o f t h e K n e e 0 . 0 2 3 I V . L a t e n c y P e r i o d 0 . 2 3 9 V . I n c o m e 0 . 8 5 6 S i g n i f i c a n c e o f F 0 . 0 0 0 0 . 0 0 0 0 . 9 7 8 0 . 9 1 6 0 . 5 1 2 Number o f C a s e s G r a n d Mean M U L T I P L E C L A S S I F I C A T I O N A N A L Y S I S 1 7 1 8 2 . 2 6 d a y s V a r i a b l e a n d C a t e g o r y I. I I . I I I . IV. T y p e o f P o s t o p e r a t i v e R e h a b l l i t a t i o n  WCB C l i n i c C o m m u n i t y None N u m b e r o f C a s e s 42 68 6 1 T y p e o f P r e o p e r a t i v e R e h a b i l i t a t i o n  None WCB C l i n i c C o m m u n i t y WCB C l i n i c a n d C o m m u n i t y P r e v i o u s H i s t o r y o f t h e K n e e  None P r e v i o u s M e n i s c e c t o m y O t h e r H i s t o r y L a t e n c y P e r i o d L e s s 1 3 6 1 t h a n 1 m o n t h m o n t h s m o n t h s y e a r m o n t h 3 m o n t h s 6 m o n t h s 1 y e a r I n c o m e L o s s P e r M o n t h N o n e $ 1 0 0 $ 1 0 0 b u t $ 3 0 0 $ 3 0 0 b u t $ 5 0 0 $ 5 0 0 I n d e p e n d e n t O p e r a t o r M u l t i p l e R S q u a r e d 1 2 8 17 24 1 4 3 6 22 22 54 5 3 20 22 55 16 40 30 2B 2 N u m b e r o f D a y s U n -a d j u s t e d D e v i a t i o n 1 9 . 4 6 1 . 4 3 - 1 5 . 0 0 - 5 . 6 0 2 1 . 1 5 6 . 8 7 9 6 . 2 4 0 . 7 8 0 . 9 1 4 . 8 3 - 6 . 8 9 - 2 . 5 5 - 0 . 8 6 - 1 . 5 6 1 6 . 6 5 5 . 5 1 0 . 9 3 7 . 1 7 7 . 4 8 8 . 1 1 2 . 2 4 E t a 0 . 3 4 0 . 3 4 0.05 0 . 1 7 0 , 1 7 N u m b e r o f D a y s A d j u s t e d D e v i a t i o n B e t a 1 9 . 6 4 0 . 8 8 - 1 4 . 5 1 - 4 . 8 2 1 1 . 8 1 8 . 9 2 1 0 0 . 8 2 0 . 2 6 0 . 6 1 1 . 5 3 2 . 8 6 1 . 9 2 1 . 1 0 1 . 4 5 6 . 2 5 - 3 . 0 1 5 . 4 8 1 . 4 8 8 . 0 3 - 8 . 9 9 1 4 . 5 4 0 . 3 3 0 ; 3 3 0 . 0 2 0 . 0 7 0 . 1 5 0 . 2 5 2 -83-T a b l e 5 . 1 0 V a r i a t i o n s i n t h e Number o f D a y s R e t u r n t o W o r k Due t o T y p e o f P o s t o p e r a t i v e R e h a b i l i t a t i o n , T y p e o f P r e o p e r a t i v e R e h a b i l i t a t i o n a n d P r e s e n c e o f P o s t e r i o r I n c i s i o n , WCB M e n i s c e c t o m y C a s e s : 1 9 7 6 & 1 9 7 7 S o u r c e o f V a r i a t i o n F S c o r e I. T y p e o f P o s t o p e r a t i v e 1 1 . 8 1 5 R e h a b i l i t a t i o n I I . T y p e o f P r e o p e r a t i v e 5 . 6 4 6 R e h a b i l i t a t i o n I I I . P r e s e n c e o f P o s t e r i o r 0 . 5 2 5 I n c i s i o n A L L CASES S i g n i f i c a n c e o f F 0 . 0 0 0 0 . 0 0 1 0 . 4 6 9 NON-SEDENTARY C A S E S ONLY F S c o r e S i g n i f i c a n c e o f F 1 0 . 8 9 5 0 . 0 0 0 3 . 2 6 0 . 0 2 1 0 . 3 5 7 0 . 5 5 1 M U L T I P L E C L A S S I F I C A T I O N A N A L Y S I S Number o f C a s e s G r a n d M e a n Number o f C a s e s I. T y p e o f P o s t o p e r a t i v e R e h a b i H t a t l o n  WCB C l i n i c C o m m u n i t y None I I . T y p e o f P r e o p e r a t i v e R e h a b i l i t a t i o n  None WCB C l i n i c C o m m u n i t y WCB C l i n i c a n d C o m m u n i t y I I I . P o s t e r i o r I n c i s i o n No p o s t e r i o r i n c i s i o n Y e s p o s t e r i o r i n c i s i o n M u l t i p l e R S q u a r e d 78 99 75 175 33 40 4 214 38 252 8 7 . 0 6 d a y s M e a n N o . o f D a y s U n -A d j u s t e d D e v i a t i o n 1 7 . 6 6 0 . 0 5 - 1 8 . 4 3 - 4 . 9 8 1 9 . 6 7 - 1 . 7 3 7 2 . 6 9 1 . 2 7 7 . 1 5 E t a 0 . 3 2 0 . 2 8 0 . 0 7 M e a n N o . o f D a y s A d j u s t e d D e v i a t i o n 1 6 . 9 1 - 0 . 5 3 - 1 6 . 8 9 - 4 . 6 4 1 1 . 5 2 3 . 7 1 7 1 . 0 3 0 . 8 3 4 . 6 8 B e t a Number o f C a s e s 71 98 66 0 . 3 0 0 . 2 4 0 . 0 4 164 31 37 3 197 38 235 8 8 . 2 8 d a y s Mean N o . o f D a y s U n -A d j u s t e d D e v i a t i o n 1 6 . 2 8 0 . 5 4 - 1 6 . 7 2 - 3 . 6 4 1 3 . 3 0 0 . 1 5 5 9 . 7 2 ,14 . 9 3 E t a M e a n N o . o f D a y s A d j u s t e d D e v i a t i o n B e t a 1 7 . 4 0 - 1 . 9 1 - 1 5 . 8 9 0 . 3 0 0 . 2 1 0 . 0 6 - 3 . 4 0 5 . 2 7 5 . 4 6 6 4 . 0 3 0 . 7 2 3 . 7 5 0 . 3 0 0 . 2 0 0 . 0 4 0 . 1 2 9 -84-which are non-sedentary and who had no degenerative knee changes causes the presence of a posterior i n c i s i o n t o approach s i g n i f i c a n c e (p = 0.095). ' These r e s u l t s are shown i n Table 5.11. Those with p o s t e r i o r i n c i s i o n s returned to work a mean of 14.32 days l a t e r than those who did not undergo po s t e r i o r i n c i s i o n s . Although these r e s u l t s are i n t e r e s t i n g , i t must be noted again that the numbers are small. 4. The E f f e c t s of Intensity of Postoperative R e h a b i l i t a t i o n An analysis of variance i n return to work for Community patients treated at d i f f e r e n t l e v e l s of i n t e n s i t y was conducted with the only other independent v a r i a b l e found to be s i g n i f i c a n t , preoperative r e h a b i l i t a t i o n . The three cases of Community-treated patients for whom no record of the number of treatments received could be found were eliminated from t h i s comparison. Table 5.12 gives the analysis of variance and multiple c l a s s i f i c a t i o n analysis f o r t h i s comparison. The i n t e n s i t y of postoperative treatment was not found to be s i g n i f i c a n t when a l l cases were considered and excluding the three sedentary cases changed the r e s u l t s i n s i g n i f i c a n t l y . This analysis i s not shown. 5. The E f f e c t s of Occupation Throughout the previous analyses, the e f f e c t s of occupation were con t r o l l e d by eliminating sedentary occupations from a l l except the i n i t i a l analysis of variance. As a f i n a l check of the e f f e c t s of occupation upon return to work, analysis of variance was calculated incorporating occupation. This analysis indicated that occupation was a s i g n i f i c a n t f a c t o r a f f e c t i n g return to work. Table 5.13 shows t h i s analysis for a l l cases, and for cases with no degenerative changes of the knee. Sedentary cases returned to work an average of 19.33 days e a r l i e r than non-sedentary cases. Adjusting for the e f f e c t s of preoperative r e h a b i l i -t a t i o n and postoperative r e h a b i l i t a t i o n increases t h i s difference to 21.75 days. However, although the mean number of days return to work for sedentary occupations was 67.9 days, and the median only 54 days, f i v e of the 21 cases with sedentary occupations returned to work at 90 days or l a t e r . The range of return to work for persons with sedentary occupations was from 7 to 243 days. -85-Table 5.11 Variations i n the Number of Days Return to Work Due to the Type of Postoperative R e h a b i l i t a t i o n , Type of Preoperative R e h a b i l i t a t i o n and Presence of Pos t e r i o r I n c i s i o n f or Those WCB Meniscectomy Cases with Non-sedentary Occupations and No Degenerative Changes of the Knee: 1976 & 1977 Source of V a r i a t i o n I. Type of Postoperative R e h a b i l i t a t i o n I I . Type of Preoperative R e h a b i l i t a t i o n I I I . Presence of Posterior I n c i s i o n F Score 8.148 7.371 2.819 Significance of F 0.000 0.000 0.095 MULTIPLE CLASSIFICATION ANALYSIS Number of Cases = 150 Grand Mean = 83.60 Variable and Category I. Type of Postoperative R e h a b i l i t a t i o n  WCB C l i n i c 40 Community 60 None 50 I I . Type of Preoperative R e h a b i l i t a t i o n  None 110 WCB C l i n i c 16 Community 22 WCB C l i n i c and Community 2 I I I . Presence of Posterior I n c i s i o n  No Posterior I n c i s i o n 126 Yes Posterior I n c i s i o n 24 Number of Days Un-Number adjusted of Cases Deviation 17.82 - 0.37 -13.82 - 5.74 22.40 3.76 94.90 -2.29 12.03 Eta 0.31 0.36 Number of Days Adjusted Deviation 19.72 - 3.07 -12.09 -5.83 14.44 9.79 97.42 -2.38 12.49 Beta 0.31 0.34 0.13 0.14 M u l t i p l e R Squared 0.232 -86-Table 5.12 Variations i n the Number of Days Return to Work Due to the Ef f e c t s of Preoperative R e h a b i l i t a t i o n and the Intensity of Postoperative R e h a b i l i t a t i o n , for WCB Meniscectomy Cases Receiving Postoperative R e h a b i l i t a t i o n i n the Community: 1976 & 1977 Source of V a r i a t i o n I. Preoperative R e h a b i l i t a t i o n I I . Intensity of Postoperative R e h a b i l i t a t i o n F Score 1.528 0.068 Significance of F 0.212 0.934 MULTIPLE CLASSIFICATION ANALYSIS Number of Cases = 106 Grand Mean = 86.99 days Variable and Category L. Type of Preoperative R e h a b i l i t a t i o n None WCB C l i n i c Community WCB C l i n i c and Community Number of Cases 70 5 29 2 Number of Days Un-adjusted Deviation - 5.33 34.01 6.18 12.01 Eta Number of Days Un-adjusted Deviation - 5.31 33.72 6.21 11.49 Beta 0.21 0.21 II . Intensity of Postoperative R e h a b i l i t a t i o n  Time intensive (4 or 5 treatments per week) Non-intensive (1 to 3 treatments per week) Began time-intensive then tapered o f f 36 68 2.51 1.09 1.66 - 0.63 7.99 - 8.44 0.05 0.04 Mu l t i p l e R Squared 0.046 Table 5,13 Variations i n the Number of Days Return to Work Due to the Type of Postoperative R e h a b i l i t a t i o n , Type of Preoperative R e h a b i l i t a t i o n and Occupation, WCB Meniscectomy Cases: 1976 & 1977 CASES WITH NO ALL CASES DEGENERATIVE CHANGES Source of V a r i a t i o n I. Type of Preoperative R e h a b i l i t a t i o n I I . Type of Postoperative R e h a b i l i t a t i o n I I I . Occupation F Score S i g n i f i c a n c e of F 15.360 0.000 7.095 0.000 5.635 0.018 F Score S i g n i f i c i a n c e of F 12.878 0.000 12.634 0.000 4.183 0.042 Number of Cases Grand Mean II . Number of Cases Type of Postoperative R e h a b i l i t a t i o n  WCB C l i n i c 82 Community 109 None 90 Type of Preoperative R e h a b i l i t a t i o n  None 199 WCB C l i n i c 36 Community 42 WCB C l i n i c and Community 4 I I I . Occupation Non-sedentary Sedentary 260 21 281 85.79 days Mean No.of Days Un-adjusted MULTIPLE CLASSIFICATION ANALYSIS 191 80.99 days Mean No. Mean No.of of Days Days Un-Adjusted Number adjusted Mean No. of Days Adjusted Deviation Eta Deviation Beta of Cases Deviation Eta Deviation Beta 19.17 0.65 -18.26 - 5.23 19.96 0.64 73.96 1.44 -17.89 0.34 0.28 18.84 - 0.75 -16.26 - 4.73 10.85 5.75 77.50 1.63 -20.12 0.31 0.25 49 71 71 141 20 27 3 171 20 23.13 0.93 -16.90 - 7.24 30.96 3.45 103.01 1.26 -10.79 0.37 0.42 20.65 0.73 -14.98 - 6.87 20.23 9.23 104.92 1.85 -15.84 0.33 0.39 0.12 0.13 0.09 0.13 M u l t i p l e R Squared 0.188 0.292 -88-C. COSTS AND BENEFITS OF THE TYPES OF POSTOPERATIVE REHABILITATION Direct payment costs were calculated using the 1977 fee schedule. The per diem rate f o r the WCB C l i n i c was $20 a day. Hospital Outpatient Departments were paid $6.50 per treatment session and pri v a t e c l i n i c s received $10.50 for the f i r s t treatment and $7.40 per subsequent treatments. Table 5.14 shows the t o t a l number of treatments i n each area for. patients i n the d i f f e r e n t r e h a b i l i t a t i o n categories. I t i s e s s e n t i a l to remember that several patients underwent treatment i n more than one area. (Patients were categorized according to the eight-week c l a s s i f i c a t i o n system explained i n Chapter I I I , Study Methodology.) This r e s u l t s i n treatment costs even within the c l a s s i f i c a t i o n of the non-treated r e h a b i l i t a t i o n group. Once more the o u t l i e r s , those cases with return to work above 300 days, are excluded from t h i s costing comparison. The three Community-treated patients for whom no record of the number of treatments could be found are also excluded. Based on the 1977 fee schedule, the average cost of r e h a b i l i t a t i n g a C l i n i c patient was $876.86. The average cost of r e h a b i l i t a t i n g a Community-treated patient was $175.48, while the cost of returning the non-treated patient to work was $32.12. Thus i t cost almost f i v e times more to treat a patient i n the C l i n i c than i n the Community, and 5% times as much to treat him i n the Community than to r i s k not t r e a t i n g him at a l l f o r the f i r s t eight weeks. The per diem cost i n the C l i n i c i n 1977 was approximately two to three times as much as that i n Community outpatient departments or i n pri v a t e c l i n i c s . Because WCB C l i n i c patients returned to work at a l a t e r date than Community patients, and because of the often more intensive treatment they received, the difference r i s e s to f i v e times the cost. I t must also be noted that the eight Community patients (7.5% of t o t a l Community patients) who also received contination of treatment at the WCB C l i n i c , represent 31.3% of the t o t a l Community costs. In addition, as the mean return to work time has indicated, wage loss benefits were paid for a longer period of time to WCB C l i n i c patients than to Community or non-treated patients. These were not calculated but they are a d o l l a r cost to the organization. It must be remembered that the $20 per day which the WCB "pays" the C l i n i c f o r treatments i s a "paper cost". It does not represent a d o l l a r outflow to the organization as do payments to Community f a c i l i t i e s . The Table 5.14 Number of Treatments Per Re h a b i l i t a t i o n Category, and Costs, WCB Meniscectomy Cases: 1976 & 1977 R e h a b i l i t a t i o n Category I WCB C l i n i c Total Number of Cases 82 WCB C l i n i c Outpatient Department Private C l i n i c 106 II Community WCB C l i n i c Outpatient Department Private C l i n i c III No Physical Therapy 90 Never treated WCB C l i n i c Outpatient Department Private C l i n i c Number of Cases Within R e h a b i l i t a t i o n Range of Mean T o t a l Category i n Treatments Number Number Costs Treatment of of Per Area Minimum Maximum Treatments Treatments Treatment 8 61 45 83 3 2 2 13 1 1 19 2 2 87 63 85 62 7 4 36.4 16.1 18.1 44.0 8.0 9.5 291 984 844 132 16 19 35@ 7.40 $20.00 6.50 45@ 10.50 99@ 7.40 $20.00 6.50 2@ 10.50 17@ 7.40 Total Costs 82 2 118 43.5 3,570 $20.00 $71,400.00 3 6 17 10.3 31 6.50 201.50 4 4 17 9.8 39 4@ 10.50 301.00 $71,902.50 5,820.00 6,396.00 6,385.00 $18,601.10 $ 2,640.00 104.00 146.80 $ 2,890.80 Average Costs Per Case $876.86 $175.48 $ 32.12 -90-The $20 covers not only the treatment of the patient, but also the operating costs of the C l i n i c (such as heat and e l e c t r i c i t y ) , the maintenance of a large support s t a f f and the treatment of more involved and thus more expensive i n j u r i e s such as amputations. What i s the benefit to the organization of t r e a t i n g patients i n the C l i n i c ? There i s better reporting and thus the organization has more information about i t s c l i e n t s . In addition, i t i s possible that the treatment of less involved i n j u r i e s at the C l i n i c subsidizes the treatment of the more expensive i n j u r i e s such as amputations. F i n a l l y , the C l i n i c possesses the p o t e n t i a l for innovation i n treatment and a coordinated approach to the r e h a b i l i t a t i o n of the i n d u s t r i a l l y - i n j u r e d worker. SUMMARY The number of days return to work was found to d i f f e r for the three postoperative r e h a b i l i t a t i o n populations. With the four o u t l i e r s over 246 days removed from the analysis, the mean return to work time f o r C l i n i c -treated patients was found to be 105.0 days, f o r Community-treated patients 86.4 days and for non-treated patients 67.5 days. Through mu l t i v a r i a t e analysis of t h e i r e f f e c t s on return to work, the type of postoperative r e h a b i l i t a t i o n and occupation were found to s i g n i f i c a n t l y a f f e c t return to work. The l o c a l e of preoperative r e h a b i l i t a t i o n was also found to be s i g n i f i c a n t , with patients preoperatively r e h a b i l i t a t e d i n the WCB C l i n i c returning to work l a t e r than the other groups of patients. This f i n d i n g i s confounded by the fact that patients preoperatively treated at the C l i n i c tend to be the same cases postoperatively treated there; however, i t was found that within each postoperative r e h a b i l i t a t i o n group, the subgroup treated at the C l i n i c (or at the C l i n i c and the Community together) returned to work the l a t e s t . The e f f e c t s of the age of the patient, degenerative changes of the knee, income, latency period, previous h i s t o r y of the knee, i n t e n s i t y of treatment and medial, l a t e r a l , or b i l a t e r a l e x c i s i o n were not found to s i g n i f i c a n t l y a f f e c t return to work. For those non-sedentary cases with no degenerative a r t h r i t i s , the presence of a posterior i n c i s i o n was found to approach s i g n i f i c a n c e ; however, the number of cases with p o s t e r i o r i n c i s i o n s was small. For Community-treated patients only, the e f f e c t of intensive therapy was not found to be s i g n i f i c a n t . - 9 1 -The average d o l l a r costs for t r e a t i n g a patient at the WCB C l i n i c was found to be almost f i v e times greater than the costs of treating the | patient i n the Community and 5% times as much to treat him i n the Community than to r i s k not t r e a t i n g him at a l l f o r the f i r s t eight weeks post-operative. There are the a d d i t i o n a l costs of the extra period on wage loss benefits f o r the C l i n i c patient. However, the treatment of the l e s s involved i n j u r y such as meniscectomy at the C l i n i c may subsidize the treatment of more involved i n j u r i e s and t h i s may be a benefit to the organization. This study has shown that treatment at the C l i n i c may be a factor i n delaying return to work. The following chapter w i l l examine t h i s f i n d i n g and develop some of the p o t e n t i a l reasons behind the delayed return to work of the WCB meniscectomy patient treated at the WCB C l i n i c . CHAPTER VI DISCUSSION OF STUDY FINDINGS -92-i The approach to the r e h a b i l i t a t i o n of the postoperative WCB meniscectomy : patient has been found to a f f e c t s i g n i f i c a n t l y return to work. WCB meniscectomy patients who received postoperative p h y s i c a l treatment at the WCB C l i n i c returned to work an average of 27.3 days l a t e r than the WCB meniscectomy patient treated i n the community. These community-treated patients returned to work an average of 21.9 days l a t e r than the WCB patient who received no postoperative p h y s i c a l therapy. Removing four men who returned to work a f t e r 300 days from these .comparisons reduces these figures to 18.6 days and 18.9 days r e s p e c t i v e l y , but the differences remain s t a t i s t i c a l l y s i g n i f i c a n t . The impact of the d i f f e r e n t treatment times on costs i s s u b s t a n t i a l . The suggestion that treatment at the WCB C l i n i c i s a factor delaying return to work i s strengthened by the a d d i t i o n a l f i n d i n g that preoperative treatment at the C l i n i c also appears to be a factor delaying return to work. Within each category of postoperative r e h a b i l i t a t i o n , the subgroups treated preoperatively at the C l i n i c were found to have the longest return to work time. Are there elements i n the approach to treatment at the C l i n i c which r e s u l t i n any encounter with the C l i n i c adversely a f f e c t i n g return to work? Why does the n o - r e h a b i l i t a t i o n approach r e s u l t i n the e a r l i e s t return to work? A framework for the analysis of the causes of delayed return to work at the C l i n i c or i n the community r e l a t i v e to the no-treatment approach i s given i n Section A of t h i s chapter. However, there are other approaches to the study findings which f a l l outside t h i s framework. These involve the merits of return to work as the only outcome measure, possible long-term e f f e c t s of treatment, study biases, and questions about the a b i l i t y to generalize the findings. Attention to these considerations i s given i n Section B. Requirements for further research are discussed i n the f i n a l s e c tion of t h i s chapter. A. A BEHAVIOURAL FRAMEWORK FOR RETURN TO WORK Return to work i s the behaviour which the r e h a b i l i t a t i o n process and the Workers' Compensation Board has as one of i t s goals. Such behaviour on the part of the patient i s influenced by h i s self-image:.; and t h i s i n turn -93-i s affected by the d e f i n i t i o n s he receives from others. These d e f i n i t i o n s i are inherent i n the labels which are applied to him. The two l a b e l s which the work-injured person receives from the WCB are the l a b e l s "disabled" and "claimant". He i s a claimant because he i s claiming compensation and disabled because i n order to receive wage loss benefits he must be assessed as unable to work. 1. The Label "Disabled" D i s a b i l i t y i s not a purely medical condition. Depending upon the s p e c i f i c s i t u a t i o n a l demands, impairment, which i s defined as any anatomic or f u n c t i o n a l abnormality or l o s s , may or may not disable the patient. D i s a b i l i t y e x i s t s when s i t u a t i o n a l c h a r a c t e r i s t i c s exclude the injured patient, preventing him from pursuing g a i n f u l employment, family or s o c i a l l i f e , and when that patient i s unable to f i n d i n c l u s i o n i n any other su i t a b l e substitute s i t u a t i o n . Impairment i s a function of the person but d i s a b i l i t y i s a function of the s o c i a l s i t u a t i o n (Reusch and Brodsky, 1968). Figure 6.1 i s a model of the pathway to d i s a b i l i t y adapted from Koshel and Granger (1978) to f i t meniscectomy. In Figure 6.1 the s i t u a t i o n a l d e f i n i t i o n s of the patient, h i s employer, family and the Workers' Compensation Board a l l a f f e c t f u n c t i o n a l l i m i t a t i o n s to produce d i s a b i l i t y . In the case of the WCB these d e f i n i t i o n s are not always subtle. The WCB reinforces the patient's s e l f - p e r c e p t i o n of d i s a b i l i t y with each l e t t e r i t sends him as a phrase such as "as long as you are disabled" i s almost always included. Sometimes the inferences are more subtle. A m u l t i d i s c i p l i n a r y , time-intensive approach to r e h a b i l i t a t i o n i s commonly used i n centres which treat major impairments such as amputations, neurological i n j u r i e s or rheumatoid a r t h r i t i s . However, when a patient with a meniscectomy or a patient with any simple s i n g l e - j o i n t i n j u r y encounters a c l i n i c which o f f e r s him the p o s s i b i l i t y of therapies i n four d i f f e r e n t departments d a i l y , the message he may be receiving i s that h i s i n j u r y must have much gravity to warrant such attention. What was a minor problem may become a serious a f f a i r due to over-emphasis. Before the patient returns to work he may be offered a half-day or f u l l - d a y work t r i a l i n the I n d u s t r i a l Department. Here, the subtle comparison may be to a sheltered workshop which to the patient may also convey the message " d i s a b i l i t y " . Functionally l i m i t e d persons i n t h i s environment may become disabled persons and doubt t h e i r a b i l i t y to work. -94-Figure 6.1 Modelling the Pathway to D i s a b i l i t y (Adapted from Koshel & Granger, 1978) "CURE" ^-(No further problems) "CURE" 4" (No further problems) ACTIVE PATHOLOGY (a torn meniscus) IMPAIRMENT (pain, e f f u s i o n , decreased range of movement, etc.) RESPONSE TO SPECIFIC TREATMENT I Medical care - conservative treatment - surgery - r e h a b i l i t a t i o n 4. RESIDUAL IMPAIRMENT (Weakness, r e s t r i c t e d range of motion, pain, etc.) \ ^ RESPONSE TO SPECIFIC TREATMENT (Medical care) (Rehabilitation) 6. FUNCTIONAL LIMITATIONS Patient's d e f i n i t i o n of the s i t u a t i o n >^T" (Needing Human Assistance) \ / 7, DISABILITY D e f i n i t i o n of the employer, family ^ D e f i n i t i o n of the WCB -95-2 . The Label "Claimant" i The l a b e l "claimant" may suggest to the injured worker that he i s i n an adversary p o s i t i o n to the agency which i s receiving h i s claim, i n t h i s case the Workers' Compensation Board. As an adversary, he may view neither the WCB nor i t s physicians or r e h a b i l i t a t i o n personnel i n an "agency r o l e " , that i s , pursuing h i s welfare as a patient. Rather, he may view them with skepticism or d i s t r u s t . S i m i l a r l y , i f WCB personnel regard the patient as a claimant, d i s t r u s t and h o s t i l i t y develop on both sides. This r e s u l t i n g " l i t i g i o u s atmosphere" does not promote return to work as the patient perceives return to work as the i n t e r e s t of the WCB but not as h i s own i n t e r e s t . I d e a l l y , return to work should be the goal of both the patient and the Workers' Compensation Board, but i n a l i t i g i o u s atmosphere opposite goals may develop. Under compensation, the primary concern of the "claimant" i s to emphasize his d i s a b i l i t y . Otherwise, i f he i s "able", benefits may be terminated. This c o n f l i c t s with the goals of r e h a b i l i t a t i o n which emphasize a b i l i t y . The patient treated at the C l i n i c probably feels the c o n f l i c t the greatest because he i s under d a i l y scrutiny as a "claimant". The community-treated patient probably does not associate h i s treatment as much with the compensation system, and the c o n f l i c t i s thus less acute. The non-treated patient has the l e a s t encounter with the health-care system or the WCB and thus he may experience the c o n f l i c t the l e a s t . 3. C e n t r a l i z a t i o n C e n t r a l i z a t i o n of the treatment of the i n d u s t r i a l l y - i n j u r e d patient may r e s u l t i n the i n t e n s i f i c a t i o n of t h i s l i t i g i o u s atmosphere. While the WCB has better information due to c e n t r a l i z a t i o n , the mixing of the new, non-h o s t i l e patient with WCB cases who may have already been defined as problems, and who most keenly f e e l and perpetuate t h i s l i t i g i o u s atmosphere, may sow the seeds of skepticism i n the new patient. D a i l y , i n close encounter with each other, compensation patients may share and strengthen t h e i r grudges against the organization. R e h a b i l i t a t i o n patients can be supportive of each other, but this support i n the C l i n i c may r e s u l t i n a "we versus them" a t t i t u d e . The l i t i g i o u s atmosphere thus builds and recovery may be delayed. -96-4. Patients' Expectations The compensation patient may expect that as long as he i s "disabled 1 from work" he need not return to work. The patient may consider himself disabled as long as he possesses any signs of impairment. A m u l t i -d i s c i p l i n a r y , time-intensive approach to r e h a b i l i t a t i o n may heighten hi s expectations of ultimate cure and thus return to work i s delayed. From personal experience as a physiotherapist at the C l i n i c , the researcher has observed that compensation patients often become very passive about the course of treatment, p a r t l y due to t h e i r fears of a l i e n a t i n g the organization and p a r t l y due to t h e i r b e l i e f that the ultimate r e s p o n s i b i l i t y for t h e i r l i f e s i t u a t i o n rests with the WCB. Feelings of p a s s i v i t y r e s u l t i n a loss of i n i t i a t i v e and a r e s u l t i n g depen-dency upon the organization. The patient i s not made an active p a r t i c i p a n t i n planning h i s treatment or h i s ultimate return to work. Rather, he abrogates a l l r e s p o n s i b i l i t y to the WCB, including r e s p o n s i b i l i t y for the decision to return to work. 5. The Role of Physicians and R e h a b i l i t a t i o n Personnel The physician and r e h a b i l i t a t i o n personnel t r e a t i n g WCB patients may have ambiguous f e e l i n g s which r e s u l t i n delaying return to work. One aspect of the ambiguity i s the h o s t i l i t y and suspicion a r i s i n g from tre a t i n g a "claimant". This may r e s u l t i n caution about treatment and the over-extending of the benefit of doubt to suppress these f e e l i n g s of h o s t i l i t y and to recover t h e i r p r o f e s s i o n a l role as the patient's agent. These c o n f l i c t s are f e l t most keenly at the C l i n i c where the personnel i s i n the d i r e c t employ of the WCB. To cope with these dual l o y a l t i e s , r e h a b i l i t a t i o n personnel may blame e i t h e r the agency f o r which they work or the patient. As return to work should be the goal of both the WCB and the patient, blaming e i t h e r may delay return to work. To recover h i s or her f e e l i n g s as the patient's agent, the physician may become over-cautious i n suggesting treatment. Rather, he or she suggests extending treatment another two weeks or beginning a half-day program or more occupational therapy, delaying return to work. Community-treated patients too are claimants, but r e h a b i l i t a t i o n i s removed from the agency against whom they are claiming. Treatment i s not associated with the compensation system and the c o n f l i c t i s thus less acute. Community physicians and r e h a b i l i t a t i o n personnel may be regarded as the -97-patient's agents or adversaries depending upon the att i t u d e they display toward him and the WCB. These attitudes may manifest themselves very complexly. For example, i t may be conveyed to the patient that the physician i s the patient's agent and that the WCB i s the adversary of both of them. The patient may then t r u s t the physician, mistrust the WCB, but believe the physician's advice on return to work. However, community physicians may not have return to work as one of t h e i r goals. As long as the patient i s content and receiving h i s wage loss b e n e f i t s , the physician may not see the need to press return to work. S i m i l a r l y , because the patient i s a compensation patient, any complaints on his part or any delayed recovery may r e s u l t i n the community physician and r e h a b i l i t a t i o n personnel t r e a t i n g him as a "claimant",and thus there i s the p o s s i b i l i t y f o r the development of a l i t i g i o u s atmosphere i n the community. The non-treated patient receives the least feedback from the health-care system and thus i s the le a s t affected by the behaviour of health professionals within the system. 6. D i f f i c u l t i e s With the Behavioural Framework The behavioural framework for the analysis of the e f f e c t s of three approaches to the r e h a b i l i t a t i o n of the WCB patient i s confounded by al t e r n a t i v e approaches to the study findings which include the merit of return to work as the only outcome measure, possible long-term e f f e c t s of treatment, and study biases. There are questions about the generaliza-b i l i t y of a framework developed from a study of meniscectomy. These d i f f i c u l t i e s are discussed i n the following section of t h i s chapter. B. CONSIDERATIONS OF STUDY FINDINGS WHICH FALL OUTSIDE THE BEHAVIOURAL FRAMEWORK 1 . Return to Work as the Only C r i t e r i o n of Outcome Return to work was chosen as the only c r i t e r i o n of outcome of th i s study because i t was measureable r e t r o s p e c t i v e l y and because i t was well suited to the goal-attainment model for program evaluation. However, return to work i s a behavioural aspect of recovery. Pathophysiological considera-tions of fun c t i o n a l or c l i n i c a l outcomes were not included i n t h i s study. It i s possible that those patients who returned to work at a l a t e r date had a better c l i n i c a l outcome than those who returned to work e a r l i e r . -98-Pathophysiological recovery may have progressed i n various ways, The three r e h a b i l i t a t i o n groups compared may have had s i m i l a r pathophysiological responses, however, patients who received no r e h a b i l i t a t i o n may have returned to work e a r l i e r with more e f f u s i o n and more fun c t i o n a l l i m i t a t i o n s than those i n the community. Patients i n the C l i n i c may have waited u n t i l most or a l l signs and symptoms subsided before returning to work. Conversely, i t i s possible that the pathophysiological recovery was affected by the treatment area. Patients who underwent intensive treatment may have exacerbated effusions and therefore recovered l a t e r than those who received le s s intensive therapy. Karumo (1976) and Seymour (1973) found p o s i t i v e c o r r e l a t i o n s between physiotherapy and effusions a f t e r meniscectomy. However, a f t e r reading a l l the case h i s t o r i e s of the patients i n the present study, the impression i s that the pathophysiological responses a f t e r menis-cectomy were s i m i l a r for the three groups. There did seem to be more effusions, f a l l s , back i n j u r i e s and such i n the C l i n i c group, however, t h i s may have been due to better reporting. The attending physicians' c l i n i c a l notes on the state of the knee did appear reasonably s i m i l a r across the groups, although no attempt was made to v e r i f y t h i s . The decision to return to work appeared to be f a i r l y a t t i t u d i n a l on the part of both physician and patient. The following physicians' reports on three cases are taken from the f i l e s . These i l l u s t r a t e the subjective responses of physicians to the presenting signs and symptoms of the patient's knee. Case No. 1 - Patient Who Received No Postoperative Physical Therapy:-42 days Postoperative, Report of the Attending Physician Patient s t i l l complains of d u l l , aching pain i n h i s knee p a r t i c u l a r l y when he runs up s t a i r s or uses his b i c y c l e . His work involves a l o t of s t a i r climbing and we have explained to him that he w i l l probably experience some ache i n the knee for some period of time but that t h i s i s not going to damage the knee and i n fact strengthening i t through t h i s sort of exercise i s a good thing. We therefore suggest that he would be ready to work i n ten days. Case No. 2 - Patient Who Received No Postoperative R e h a b i l i t a t i o n : -80 days Postoperative, Report of the Attending Physician C l i n i c a l review finds the knee functioning r e a l l y pretty w e l l . There i s a l i t t l e b i t of s y n o v i t i s reaction and the pes anserinus tendon i s a l i t t l e b i t puffy and he can f e e l i t skid a l i t t l e b i t as i t excurses along the j o i n t l i n e during f l e x i o n and extension. Quadriceps i s i n good c o n t r o l , the p a t e l l a i s smooth, I n c i s i o n a l scar i s healing n i c e l y , I think there i s enough r e h a b i l i t a t i o n i n -99-t h i s knee for a t r i a l at work and he w i l l go back on t h i s basis i n four days. I won't bother him with continuing v i s i t s unless he develops some problems and he knows he i s welcome to bring i t for my scrutiny. Case No. 3 - C l i n i c P a t i e n t : - 70 days Postoperative, Report of the C l i n i c Physician Continued excellent improvement. There are no pains i n the knee, no e f f u s i o n and he can now l i f t 15 l b s . He can f l e x to 125°, can hop and squat without any problem. Manipulation of the p a t e l l a produces no pain and he has good i n t e g r i t y of a l l ligaments. The only disturbing feature i s continued high degree of wasting on the l e f t thigh and c a l f . The l e f t thigh i s 2 cms. less than the r i g h t one handsbreadth above the superior pole of the p a t e l l a and the l e f t c a l f i s 1 cm. le s s i n maximum circumference than the r i g h t . He t e l l s me when he returns to work he w i l l only be expected to walk around and not operate machines. If t h i s i s the case I f e e l he w i l l be f i t enough to return to work by the next consultation. Review: Two weeks. In the meantime he i s to continue with his Grade II R.T. and O.T. programs and he may have a cautious t r i a l i n the foot-powered lathe adjusted by the Occupational Therapist. He may be downgraded at t h e i r d i s c r e t i o n at the f i r s t sign of any increased symptomology. Same Patient as Above:- 84 days Postoperative, Report of the C l i n i c Physician This patient has been doing very well and he i s now l i f t i n g 20 l b s . i s o m e t r i c a l l y i n Room 36. The knee i s cool and dry and he can f l e x I t from f u l l extension to 125°. He can jog and hop without discomfort. He has good s t a b i l i t y of a l l ligaments. Impression: He i s almost f i t enough to return to work but I would l i k e him to do a f u l l - d a y program for a few weeks before doing so, though he may return to me e a r l i e r i f he f e e l s he can handle h i s job at an e a r l i e r stage. Review: Two weeks. This i s not to suggest that these reactions to the signs and symptoms of the knee are generalizable to a l l C l i n i c physicians or to a l l physicians who do not order postoperative therapy. However, i t does suggest that a major aspect of return to work i s a t t i t u d i n a l , and not a r e f l e c t i o n only of the pathophysiological state of the knee. The l i t e r a t u r e review has indicated that a high percentage of post-meniscectomy knees maintain some symptoms and signs years a f t e r surgery. The decision to return to work with symptomology thus must be a t t i t u d i n a l . 2, Long-Term Results This was a short-term study of the e f f e c t s of meniscectomy on return -100-to work. There was no long-term followup. I t Is possible that the state of the patient's knee 20 years postoperative may vary with the approach to ' r e h a b i l i t a t i o n . Conceivably, early return to work may have adverse long-term e f f e c t s , although i t must be remembered that none of the groups i n the study had e a r l i e r times of return to work than suggested i n the l i t e r a t u r e . (See Table 2.1, page 11.) It i s also possible that intensive therapy produces adverse long-term e f f e c t s or conversely intensive therapy may produce p o s i t i v e long-term e f f e c t s , Appel (1970) found that i f patients who had o s t e o a r t h r i t i s at the time of operation were excluded, postoperative muscular t r a i n i n g gave r i s e to a s i g n i f i c a n t l y lower frequency of unsatis-factory r e s u l t s i n the long run. Appel does not describe the i n t e n s i t y of the muscular t r a i n i n g . 3. Study Biases Throughout t h i s t h e s i s , an attempt has been made to stress i t s l i m i t a t i o n s . It has a l l the p i t f a l l s of retrospective studies, such as inaccuracies of recording. The data was c o l l e c t e d from f i l e s which had not been intended for t h i s use, thus much i n t e r p r e t a t i o n was required to c o l l e c t and codify the data i n a meaningful way for a n a l y s i s . In a retrospective examination,• assignment to groups i s non-random. Selection of treatment f a c i l i t y was found to be based upon the physician's treatment philosophy. Certain physicians r e f e r more often to the C l i n i c , others to community f a c i l i t i e s while some do not ro u t i n e l y order p h y s i c a l therapy. These findings conform with those of Ward et a l (1978) who found that the rate of r e f e r r a l of new outpatients seen by 18 orthopedic surgeons, to physiotherapy ranged widely; the d i f f e r i n g c h a r a c t e r i s t i c s of the patients did not account for these v a r i a t i o n s . Some physicians i n the present study did appear to vary t h e i r r e f e r r a l s . Whether t h i s was due to the condition of the knee, a c c e s s i b i l i t y , or change i n treatment philosophy cannot be known. It can be suggested that physicians r e f e r t h e i r worst cases to the C l i n i c and indeed the C l i n i c population showed more evidence of osteo-a r t h r i t i s than the other groups. However, there were cases of severe o s t e o a r t h r i t i s elsewhere but there were none found at the C l i n i c . The higher incidence of o s t e o a r t h r i t i s at the C l i n i c may be p a r t l y explained by a number of fa c t o r s . The c l a s s i f i c a t i o n of s e v e r i t y was dependent upon c l i n i c a l records, A physician's d e s c r i p t i o n of o s t e o a r t h r i t i s i s very subjective. Thus, physicians who referred to the C l i n i c may define osteo--101-a r t h r i t i s more s t r i c t l y than others. C l i n i c patients tended to receive t h e i r x-rays at the C l i n i c and the reports of these were always on f i l e and 1 often more d e t a i l e d than reports from the community. An absence of any mention of the state of the knee at operation was interpreted as a normal knee; however, i t i s possible that there was o s t e o a r t h r i t i s and t h i s may have affected the incidence of o s t e o a r t h r i t i s . The retrospective c l a s s i f i c a t i o n of degenerative changes of the knee remains a weakness of the study. Aside from the problem that physicians d i f f e r on the l a b e l l i n g of changes, much subjective i n t e r p r e t a t i o n was required to l i m i t the c l a s s i f i c a t i o n system to four categories. A ,reviewer recently c r i t i c i z e d the l a b e l l i n g of the patient referred to i n the operative and x-ray report on page 42 as a case of "minimal" degenerative changes. He suggests that a mention of "medial j o i n t degener-at i o n " i n the operative report, and an x-ray fi n d i n g of "a j o i n t already narrowed" should be considered as being "moderate" i f not even "severe". The "narrowing" suggests s u f f i c i e n t wearing or erosion of weightbearing c a r t i l a g e which must be considerable to v i s u a l l y narrow the space on x-ray. This case was l a b e l l e d as "minimal" p a r t l y because the x-ray report referred to "minor c a r t i l a g e damage", s i m i l a r to other reports studied. In the subsequent four months, further damage to the j o i n t could occur. With-out a d e s c r i p t i v e operative report, l a b e l l i n g the case remained a problem. C l a s s i f i c a t i o n i s a p i t f a l l of retrospective studies. Because of the discomfort with the c l a s s i f i c a t i o n system for degenerative a r t h r i t i s , a l l cases of degenerative a r t h r i t i s were eliminated from the f i n a l analyses performed. Unfortunately, no mention of degenerative a r t h r i t i s does not neces s a r i l y i n d i c a t e that the j o i n t was sound unless the surgeon made reference to the state of the j o i n t . I f resources had been a v a i l a b l e , i t would have been preferable to review a l l x-rays with a r a d i o l o g i s t . However, the operative reports would have remained inaccurate. Unfortunately, t h i s weakness can be eliminated only by a prospective study with c a r e f u l v i s u a l i z a t i o n of the knee during the operative procedure by one examiner, or a few who have standardized methods of examination. 4. . G e n e r a l i z a b i l i t y of the Study Findings Can the behavioural framework of analysis of the causes of delayed recovery post-meniscectomy be applied to other disorders aside from meniscectomy? Further i n v e s t i g a t i o n i s required to determine i f the i -102-findings of the study are s p e c i f i c to the period studied, to meniscectomy only, or to a l l disorders. I d e a l l y , a prospective examination of another ( condition should be i n i t i a t e d . Prospective examination would allow for more con t r o l , Another morbid condition would Indicate the g e n e r a l i z a b i l i t y of the fi n d i n g s , In the s p e c i f i c example of the compensation patient post ^ -meniscectomy, p h y s i c a l therapy may be unnecessary or even delay return to work. It i s not suggested that this f i n d i n g can be generalized to other knee conditions or to the nori-compensation patient, without further i n v e s t i g a t i o n of the value of ph y s i c a l therapy. C. REQUIREMENTS FOR FURTHER RESEARCH 1. The Need f o r a Medical Information System That the WCB i s eager to sponsor research projects has been made evident by the excellent support that i t has given t h i s p r o j ect. This thesis has shown that through a retrospective study of WCB f i l e s , outcome evaluation i s po s s i b l e . Whether or not the WCB concurs with the conclusions of t h i s study, the information which i t has provided i n reference to morbidity data, demographic data and r e f e r r a l patterns information, a l l have contributed to the Board's knowledge about i t s e l f , knowledge which i t has i n i t s possession but f o r which a simple r e t r i e v a l mechanism does not e x i s t . The WCB i s a major source of medical information. I t constantly receives information of high p o t e n t i a l f o r the study of morbidity, evalua-t i o n of medical care and occupational health research. Unfortunately, t h i s information i s contained i n i n d i v i d u a l claim f i l e s . There i s presently no system which c o d i f i e s and computerizes t h i s information. Data f o r t h i s study was gathered by hand through an examination of a l l meniscectomy claim f i l e s from a c e r t a i n period. It was a slow, expensive, painstaking process and i s a deterrent to research. The WCB does have a computerized information system f o r payments but i t does not have a Medical Information System. In i n t e r n a l WCB reports, Dr. C. Robertson, former Medical O f f i c e r , has documented the need for a Medical Information System. This study i s an example of the type of research which could be done i f such a system were a v a i l a b l e . The Board would possess a medical data bank invaluable to i t s e l f for s e l f - e v a l u a t i o n and to the health-care system as a whole. Such a system could function for medical audit and could contribute to the s e t t i n g -103-of standards of care or c r i t e r i a for management. Dr. Robertson has documented the research p o s s i b i l i t i e s which a proper Medical Information System could contribute. The Board would be able to study time loss by diagnosis. It could do outcome evaluation and study the effectiveness of physiotherapy according to i t s time, i n i t i a t i o n and duration. I t could do comparative studies of conservative versus s u r g i c a l treatment. I t could i n i t i a t e prospective studies. Accident prevention could receive morbidity data which demonstrates the health problems experienced i n industry. Without such a system the Board can continue to sponsor studies such as t h i s one. However, the WCB i s missing the wealth of information i t has i n i t s possession but cannot r e t r i e v e . The q u a l i t y of the studies and the numbers of studies would a l l improve with a well-thought-out medical and management information system. 2. The Need for R e h a b i l i t a t i o n Research This study has found that f or the WCB meniscectomy patient, no postoperative p h y s i c a l therapy was the most e f f e c t i v e i n returning the patient to work. Can t h i s f i n d i n g be generalized to non-compensable cases? There i s a need f o r much more program evaluation within r e h a b i l i t a t i o n . Many r e h a b i l i t a t i o n procedures have i n the past been accepted on f a i t h . Documentation i s now required to prove or disprove e f f e c t i v e n e s s . 3. The Need for Compensation Research Compensation i s a growing element i n society yet i t i s not understood. The compensation patient and the WCB have been much maligned to the detriment of themselves and the health professionals serving them. There i s a need for vigorous research to determine the e f f e c t of compensation on recovery. I t must be determined what elements within compensation produce these e f f e c t s . The compensation system i s under attack from many segments of society, yet presently, without research, i t does not have the s e l f -knowledge to defend i t s e l f e f f e c t i v e l y . -104-CONCLUSIONS ! The behavioural framework for the analysis of the e f f e c t s of r e h a b i l i t a t i o n of the WCB meniscectomy patient i s a complex, i n t e r a c t i v e process between the patient, the physician, r e h a b i l i t a t i o n personnel and the WCB. There i s no one element within the process which can be i s o l a t e d as p r i m a r i l y responsible f o r delayed return to work of the C l i n i c p a t i e n t . Confounding the behavioural framework are alternate approaches to delayed return to work which include the merit of return to work as the only outcome measure, possible long-term e f f e c t s , the g e n e r a l i z a b i l i t y of meniscectomy to other conditions, and s e l e c t i o n biases. The object of th i s thesis has been to examine the WCB systemof r e h a b i l i -t a t i o n . Although i t has been concluded that the approach at the WCB C l i n i c delays return to work, i t i s not suggested or believed that t h i s thesis i s a d e f i n i t i v e statement of cause or e f f e c t . Rather, i t must be taken as a preliminary i n v e s t i g a t i o n into the e f f i c i e n c y and effectiveness of the WCB model of r e h a b i l i t a t i o n . -105-BIBLIOGRAPHY 1 BOOKS Helf e t , A.J. Disorders of the Knee. J.B. L i p p i n c o t t Co., P h i l a d e l p h i a . Toronto 1974. Schulberg, H.C., Sheldon, A., and Baker, F. Program Evaluation i n the  Health F i e l d . Behavioural P u b l i c a t i o n s , Inc., 1969. S m i l l i e , I.S. Injuries of the Knee J o i n t . 5th Ed. C h u r c h i l l , Livingstone, Edinburgh, London and New York, 1978. Steers, R.M. Organizational Effectiveness, A Behavioural View. Goodyear Publishing Co. Inc., Santa Monica, C a l i f o r n i a , 1977. Szasz, T.S. The Myth of Mental I l l n e s s . Harper and Row, New York, Evanstan, San Francisco, London, 1977. PERIODICALS Appel, H. "Late Results A f t e r Meniscectomy i n the Knee J o i n t . A C l i n i c a l Roentgenologic Follow-Up Examination". Acta Orthopaedica  Scandinavica (Suppl. 133) 1+, 1970. Beals, R.K., and Hickman, N.W. " I n d u s t r i a l Injuries of the Back and Extremities: Comprehensive Evaluation - An Aid i n Prognosis and Management: A Study of One Hundred and Eighty Patients". The  Journal of Bone and Joint Surgery". 54: 1593-1611, December 1972. Behan, R.C. and H i r s c h f i e l d , A.W. "The Accident Process I I . Toward More Rational Treatment of I n d u s t r i a l I n j u r i e s " . Journal of the  American Medical Association. 186(4): 300-306, October 26, 1963. Benton, J.G., Brown, H., and R i n z l e r , S.H. "Objective Evaluation of Physical and Drug Therapy i n the R e h a b i l i t a t i o n of the Hemiplegic Patient". American Heart Journal. 42:719-732, 1951. Breckenridge, K. "Medical R e h a b i l i t a t i o n Program Evaluation". Archives  of Physical Medicine and R e h a b i l i t a t i o n . 59(9): 419-423, September 1978. Brodsky, CM. "Compensation I l l n e s s as a Retirement Channel". Journal of  the American G e r i a t r i c Society. 19(1): 51-60, January 1971. Carey, R.G., and Posavac, E.J. "Program Evaluation of a Physical Medicine and R e h a b i l i t a t i o n Unit: A New Approach". Archives of  Physical Medicine and R e h a b i l i t a t i o n . 59(7): 330-337, July 1978. C a r r o l , T.E. "Workmen's Compensation: A Senile Form of S o c i a l Insurance". Journal of R e h a b i l i t a t i o n . 35(3): 15-18, May-June 1969. -106-Cole, E,S. " P s y c h i a t r i c Aspects of Compensable Injury". The Medical  Journal of A u s t r a l i a . 1: 93-100, January 1970. Curran, W.J. "Workmen's Compensation Lump-Sum Settlements, and Re h a b i l i t a t i o n " . American Journal of Public Health. 60(6): 1139, June 1970. Daitz, B.D. "The Challenge of D i s a b i l i t y " . American Journal of Public  Health. 55(4): 528-534, A p r i l 1965. Dandy, D.J. "Early Results of Closed P a r t i a l Meniscectomy". B r i t i s h  Medical Journal. 1: 1099-1101, 1978. Dandy, D.J.,and Jackson, R.W. "The Diagnosis of Problems A f t e r Meniscec-tomy". Journal of Bone and Joint Surgery. (Br.) 57(3): 349-52, August 1975. Debnam, J.W., and Staple, T.W. "Arthrography of the Knee A f t e r Meniscectomy". Radiology. 113(1): 67-71, October 1974. Denistan, O.L., and Rosenstock, I.M. "The V a l i d i t y of Non-Experimental Designs for Evaluating Health Services". Health Services Reports. 88(2): 153-164, February 1973. Donabedian, A. "Evaluating the Quality of Medical Care". Milbank Memorial  Fund Quarterly. 44(3): 166-206, July 1966. Duf f i n , D. "Knee Strength and Function Following Meniscectomy". Physiotherapy. 63(11): 362-3, November 1977. Enelow, A.J. " I n d u s t r i a l I n j u r i e s : P r e d i c t i o n and Prevention of Psychological Complications". Journal of Occupational Medicine. 10(11): 683-687, November 1968. Feldman, D.J., Lee, P.R., Unterecker, J . , Lloyd, K., Rusk, H.A., and Toole, A. "A Comparison of Functionally Oriented Medical Care and Formal R e h a b i l i t a t i o n i n theManagement of Patients with Hemiplegia Due to Cerebrovascular Disease". Journal of Chronic Diseases. 15: 297-310, 1962. Fessel, W.J., and Van Brunt, E.E. "Assessing Quality of Care From the Medical Record". New England Journal of Medicine. 286(3): 134-138, January 20, 1972. Fowler, D.R., and Mayfield, D.G. " E f f e c t of D i s a b i l i t y Compensation: D i s a b i l i t y Symptoms and Motivation f o r Treatment". Archives of  Environmental Health. 19: 719-215, November 1969. Gear, M.W.L. "The Late Results of Meniscectomy". The B r i t i s h Journal of  Surgery. 54(4): 270-272, A p r i l 1967. Goldberg, R.T. " R e h a b i l i t a t i o n Research: New Di r e c t i o n s " . Journal of R e h a b i l i t a t i o n . 40(3): 12-14, May-June 1974. -107-Gordon, R.E., Lyons, H., Munij, C., Davis, H., Chudnowsky, N. , White, W., Springer, P., Gagliano, T. , and Haynes, K. "Can Compensation Hurt the Sick and Injured? The Active Dependency Syndrome". Journal of the  F l o r i d a Medical Association. 60(4): 36-39, A p r i l 1973. Gough, J.V. "Postoperative Management of Meniscectomy Patients". Physiotherapy. 61(4): 109-10, A p r i l 1975. Halstead, L.S. "Team Care i n Chronic I l l n e s s : A C r i t i c a l Review of the L i t e r a t u r e of the Past 25 Years". Archives of Physical Medicine and  R e h a b i l i t a t i o n . 57: 507-511, November 1976. H i r s c h f i e l d , A.H., and Behan, R.C. "The Accident Process I. E t i o l o g i c a l Considerations of I n d u s t r i a l I n j u r i e s . Journal of the American  Medical Association. 186(3): 193-199, October 19, 1963. Houston, J.C. "A Simple Meniscectomy". Journal of Sports Medicine. 3(4): 179-187, July-August 1975. Huckel, J.R. "Is Meniscectomy a Benign Procedure? A Long-Term Follow-up Study". Canadian Journal of Surgery. 8:254-260, July 1965. Hudgins, W.R. "Compensation and Success of Lumbar Disc Surgery". Texas  Medicine. 70(10): 62-5, October 1974. Jackson, J.P. "Internal Derangement of the Knee". Nursing Times. 72(17): 651-4, A p r i l 1976. Jenkins, D.G., Imms, F.J., Prestridge, S.P., and Smalls, G.I. "Muscle Strength Before and A f t e r Meniscectomy: A Comparison of Methods of Postoperative Management". Rheumatology and R e h a b i l i t a t i o n . 15(3): 153-5, August 1976. Johnson, R.J., Kettelkamp, D.D., Clark, W. , and Leaverton, P. "Factors A f f e c t i n g Late Results A f t e r Meniscectomy". Journal of Bone and  Jo i n t Surgery (Am.) 56: 717-29, June 1974. Karumo, I. "Intensive Physical Therapy Af t e r Meniscectomy". Annales  Chirurgiae et Gynaecologiae. 66(1): 41-46, 1977. Katz, S., Jackson, B.A., J a f f e , M.W., L i t t e l , A.S., and Turk, C.E. " M u l t i d i s c i p l i n a r y Studies of I l l n e s s i n Aged Persons - VI. Comparison Study of Rehabilitated and Non-Rehabilitated Patients with Fracture of the Hip". Journal of Chronic Diseases. 15: 979-984, 1962. Katz, S., Vignos, P.J., Moskowitz, R.W., Thompson, H.M., and Svec, K.H. "Comprehensive Outpatient Care i n Rheumatoid A r t h r i t i s " . Journal  of the American Medical Association. 206(6): 1249-1254, 1968. Kellegren, J.H., and Lawrence, J.S. "Radiological Assessment of Osteoarthrosis". Annals of Rheumatic Diseases. 16:494-502, 1957. Kessner, D.M., Kalk, C.E., and Singer, J . "Assessing Health Quality -the Case for Tracers". New England Journal of Medicine. 288(4): 189-194, 1973. -108-Koshel, J . J . , and Granger, C.V, " R e h a b i l i t a t i o n Terminology: Who Is Severely Disabled?" R e h a b i l i t a t i o n L i t e r a t u r e . 3(4): 102^-106, A p r i l 1978. Krussen, E.M, "Compensation Factors i n Low Back I n j u r i e s " , Journal of the  American Medical Association. 166(10): 1128, March 1958, Leonard, M,A, "An Evaluation of Two Post-Meniscectomy Regimes". Physiotherapy. 61(4): 110-111, A p r i l 1975. McGinty, J.B,, Geuss, L,F,, and Marvin, R,A. " P a r t i a l or Total Meniscectomy: A Comparative Analysis", Journal of Bone and Joint Surgery (Am.) 59-A(6): 763, September 1977, Martin, R.D, "Secondary Gain, Everybody's R a t i o n a l i z a t i o n " . Journal of  Occupational Medicine. 16(12): 800^-801, December 1974. Meade, T,W. "Problems for the Researcher Worker i n R e h a b i l i t a t i o n Studies". Rheumatology and R e h a b i l i t a t i o n . 17(4): 254-6, November 1977 Modlin, H,C, "The Post^-Accident Anxiety Syndrome: Psychosocial Aspects". American Journal of Psychiatry. 123(8): 1008-1012, February 1967. N a f t u l i n , D,N. "The Psychosocial E f f e c t s of L i t i g a t i o n on the Indus-t r i a l l y Injured Patient: A Research Plea". I n d u s t r i a l Medicine and  Surgery, 39(4): 167-170, A p r i l 1970. Nichols, P.J.R, "Outcome Measures i n R e h a b i l i t a t i o n " . Rheumatology and  R e h a b i l i t a t i o n . 15(3): 170-173, August 1976. Noble, J . " C l i n i c a l Features of the Degenerate Meniscus With the Results of Meniscectomy". B r i t i s h Journal of Surgery. 62(12) 977-981, December 1975. O'Donoghue, D.H. " P a t e l l a r Malacia: A C l i n i c a l Study". Hospital f o r  Joint Diseases B u l l e t i n .17(1): 1-19, A p r i l 1956. Outerbridge, R.E. "The Etiology of Chondromalacia P a t e l l a " . Journal of  Bone and Joint Surgery. 43B(4): 752-757, November 1961. — "Further Studies on the Etiology of Chondromalacia P a t e l l a " . Journal of Bone and Joint Surgery. 46B(2) : 179-190, May 1964. Parker, N. "Malingering". The Medical Journal of A u s t r a l i a . 2:1308-1311, December 1972. Perey, 0. "Follow-up Results of Meniscectomies With Regard to the Working Capacity". Acta Orthopaedica Scandinavica. 32: 457-459, 1962. Ruesch, J , ? and Brodsky, C.M. "The Concept of S o c i a l D i s a b i l i t y " . Archives of General Psychiatry. 19: 394-403, October 1968. Seymour, N, "The Effectiveness of Physiotherapy Af t e r Medial Meniscectomy". B r i t i s h Journal of Surgery. 56(7): 518-520, July 1969, Sommerville, J,G, "The Impact of the R e h a b i l i t a t i o n Services on Sickness Absenteeism'', Proceedings of the Royal Society of Medicine. 63: 1146-1150, November 1970. -109-Szasz, T.S. "Malingering - 'Diagnosis' or So c i a l Condemnation?" Archives of Neurology and Psychiatry. 76: 432—443, 1956, i Tapper, E.M., and Hoover, N.W. "Late Results A f t e r Meniscectomy". Journal of Bone and Joint Surgery (Am.) 51-A: 517-526, A p r i l 1969. Tracy, G.D. "Prolonged D i s a b i l i t y A f t e r Compensable Injury". Medical  Journal of A u s t r a l i a . 2: 1305-1307, December 1972, V i d a l , J . , and Dimeglio, A. "R e h a b i l i t a t i o n of the Knee Aft e r Operation". CAH Reeducation et Readaptation. 11(1): 11-19, 1976 (French). Ward, A.W.M., Williams, B.T., and Dixon, R.A. "Physiotherapy: I t s Pr e s c r i p t i o n and Implementation for Orthopaedic Outpatients". Rheumatology and R e h a b i l i t a t i o n . 17(1): 14-22. Weinstein, M.R. "The I l l n e s s Process: Psychosocial Hazards of D i s a b i l i t y Programs". Journal of the American Medical Association. 204(3): 110-121, A p r i l 1968. White, A.W.M. "Low Back Pain i n Men Receiving Workmen's Compensation". Canadian Medical Association Journal. 95(2): 50-56, July 9, 1966. "Low Back Pain i n Men Receiving Workmen's Compensation: A Followup Study". Canadian Medical Association Journal. 101(2): 61-67, July 26, 1969. Worrel, R.V. "Incidence of Chondromalacia of P a t e l l a Following Meniscectomy of Knee J o i n t " . New York State Journal of Medicine. 73: 860-864, A p r i l 1, 1973. Wynn Parry, C.B., Nichols, P.J.R., and Lewis, N.R. "Meniscectomy: A Review of 1,723 Cases". Annals of Physical Medicine. 4: ,201-215 May 1958. PROCEEDINGS Milbrandt, W.E. "A Comprehensive and Progressive R e h a b i l i t a t i v e Program for Low Back S t r a i n " . Proceedings: International Symposium on the  Re h a b i l i t a t i o n of the I n d u s t r i a l l y Injured. A p r i l 24 to 27, 1978, Vancouver, B.C., Canada. Sponsored by the Workers' Compensation Board of B r i t i s h Columbia i n cooperation with R e h a b i l i t a t i o n Inter-n a t i o n a l . Pg. 76-78. Mossman, P.L. "The I n d u s t r i a l l y Injured: Do We Understand This Population of Medical Consumers". Proceedings: International Symposium on the  Re h a b i l i t a t i o n of the I n d u s t r i a l l y Injured. A p r i l 24 to 27, 1978, Vancouver, B.C., Canada. Sponsored by the Workers' Compensation Board of B r i t i s h Columbia i n cooperation with R e h a b i l i t a t i o n Inter-n a t i o n a l . Pg. 76-78. Nagi, Saad J . "Some Conceptual Issues i n D i s a b i l i t y and R e h a b i l i t a t i o n " i n Sussman, M.B. ed. Sociology and R e h a b i l i t a t i o n , American Socio-l o g i c a l Association, Washington, D.C, 1965. -110-EDITQRIALS JAMA. "Compensation Cnndrums". ' Journal of t*» American Medical A s s o c i a t i o n f 186(3): 254, October 19, 1963,' Lancet. "Unnecessary Meniscectomy". ^ Lancet 1(7953): 235-6, January 31, 1976. UNPUBLISHED PAPERS Robertson, CM, A Review of Back Injury Claims at the B.C. Workers Compensation Board, A Paper Based On a Study of a 5% Random Sample of 10,768 "Back" Claims Processed During the Year 1974. A p r i l 21, 1977, ANNUAL REPORTS Workers' Compensation Board of B r i t i s h Columbia, for the Year Ended December 31, 1976. S i x t i e t h Annual Report APPENDIX Tables of Diagnostic Examinations with A v a i l a b i l i t y of Reports -112-Table I Number of WCB Meniscectomy Cases Who Experienced Preoperative X^-ray Examination, and A v a i l a b i l i t y of Reports, 1976 & 1977 Number of Cases Patient underwent x-ray, 212 report on f i l e Patient underwent x-ray, no 34 report on f i l e , but findings mentioned i n physician's report Patient underwent x-ray, no report on f i l e and findings not mentioned No x-ray 32 Total Cases 285 -113-Table II Number of WCB Meniscectomy Cases Who Experienced Preoperative Arthrographic Examination, and A v a i l a b i l i t y of Reports, 1976 & 1977 Number of Cases Patient underwent arthrographic 114 examination, report on f i l e Patient underwent arthrographic 26 examination, no report on f i l e Patient did not undergo arthrographic 145 examination T o t a l Cases 285 Table I I I Number of WCB Meniscectomy Cases Who Underwent Preoperative Arthroscopic Examination, 1976 & 1977 -114-Number of Cases Patient underwent arthroscopy, 23 report on f i l e Patient underwent arthroscopy, 2 no report on f i l e Patient did not undergo arthroscopy 260 Total Cases 285 -115-Table IV Number of Claim F i l e s Which Contained Operative Reports, WCB Meniscectomy Cases: 1976 & 1977 Number of F i l e s Operative report on f i l e 255 Operative report not on f i l e , but pathology report a v a i l a b l e Operative report not on f i l e , but h o s p i t a l discharge summary avai l a b l e Operative report not on f i l e , 22 no pathology report or discharge summary ava i l a b l e T o t a l F i l e s 285 

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