Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Clinical and biomechanical changes following a pre-operative muscle strengthening intervention for people… Guenther, Jerrad 2014

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata

Download

Media
24-ubc_2015_february_guenther_jerrad.pdf [ 2.77MB ]
Metadata
JSON: 24-1.0135607.json
JSON-LD: 24-1.0135607-ld.json
RDF/XML (Pretty): 24-1.0135607-rdf.xml
RDF/JSON: 24-1.0135607-rdf.json
Turtle: 24-1.0135607-turtle.txt
N-Triples: 24-1.0135607-rdf-ntriples.txt
Original Record: 24-1.0135607-source.json
Full Text
24-1.0135607-fulltext.txt
Citation
24-1.0135607.ris

Full Text

Clinical and biomechanical changes following a pre-operative muscle strengthening intervention for people with femoroacetabular impingement   by  Jerrad Guenther  B.Sc., University of Winnipeg, 2011    A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF  MASTER OF SCIENCE   in  THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES  (Rehabilitation Sciences)  THE UNIVERSITY OF BRITISH COLUMBIA  (Vancouver)  November 2014   © Jerrad Guenther, 2014 ii  Abstract  Introduction: Femoroacetabular impingement (FAI) is a pathomechanical process of the hip joint that has been linked to the early development of hip osteoarthritis. FAI morphology usually progresses gradually and can limit the ability of individuals to engage in sports and causes pain during activities of daily living. These impairments can lead to loss of range of motion, muscle weakness and altered walking biomechanics. Currently, surgery is the common treatment, however little is known about the effects of muscle strengthening in this population. Based on the results of similar programs in other pathologies, muscle strengthening may alleviate this muscle weakness and hip pain. Our goal was to investigate the effects of a pre-surgical hip muscle strengthening intervention on hip strength, pain and function in those with FAI. Methods: This was a within subject, pre-test – post-test intervention study examining the effects of a 10-week hip muscle strengthening program in 20 individuals (18 males) with FAI before hip surgery. Clinical outcomes including maximum isometric hip strength, hip pain and physical function were collected before and after the strengthening intervention. During the intervention, participants progressed through three phases of increasing resistance and functionality as they received a bilateral hip strengthening program consisting of 4-6 exercises per phase. Results: Maximum isometric hip strength significantly increased in abduction (p=0.008), adduction (p=0.021) and internal rotation (p=0.006) at follow-up.  Flexion, extension and external rotation strength changes did not reach significance. Self-reported HOOS pain iii  subscale scores (p<0.01), HOOS ADL scores (p<0.01) and NRS pain scores (p<0.001) significantly improved at follow-up. Objective function measured by the Timed Stair Climb (p<0.001) also significantly improved at follow-up.  Conclusion: Findings from this study showed that a 10-week hip muscle strengthening program could be safely completed by adults with FAI and that statistically significant changes in clinical and biomechanical outcomes were achieved. Findings of this study can improve our understanding of FAI and may be useful for clinicians for preventive, treatment and maintenance purposes.              iv  Preface  This thesis contains the work of a research study conducted by Jerrad Guenther under the supervision of Dr. Michael Hunt with guidance from Dr. Michael Gilbart, and Dr. Kay Crossley. The study design, data collection, administration of intervention, data analysis, and writing the manuscript were primarily the work of the candidate. A selection of work from this thesis will be submitted for publication in a relevant peer-reviewed journal.  Ethical approval for this research study was provided by the University of British Columbia Clinical Research Ethics Board on September 5, 2012 and by the Vancouver Coastal Health Research Institute on September 11, 2012. The Clinical Research Ethics Board number is H12-01400 for the University of British Columbia and V12-01400 for Vancouver Coastal Health. v  Table of Contents  Abstract .................................................................................................................................... ii Preface ......................................................................................................................................iv Table of Contents ..................................................................................................................... v List of Tables ............................................................................................................................ix List of Figures .......................................................................................................................... x List of Abbreviations ...............................................................................................................xi Acknowledgments ................................................................................................................. xiii Chapter 1: Introduction and Background ............................................................................... 1 1.1 Overview of Femoroacetabular Impingement ................................................................... 1 1.2 Etiology of FAI .................................................................................................................. 1 1.3 Epidemiology of FAI ......................................................................................................... 3 1.4 Structure and Function of the Hip ..................................................................................... 5 1.4.1 Muscles of the hip ................................................................................................... 6 1.5 Types of FAI ..................................................................................................................... 7 1.5.1 Cam impingement .................................................................................................. 9 1.5.2 Pincer impingement ...............................................................................................10 1.6 Diagnosis of FAI ..............................................................................................................11 1.6.1 Clinical presentation ..............................................................................................11 1.6.2 Physical examination .............................................................................................12 1.6.3 Radiographic assessment .....................................................................................13 1.6.4 Imaging in FAI .......................................................................................................14 1.7 Treatment for FAI ............................................................................................................15 vi  1.7.1 Surgical treatment .................................................................................................15 1.7.2 Conservative treatment ..........................................................................................17 1.8 Role of Muscle Strength in FAI ........................................................................................19 1.8.1 Hip muscle weakness in FAI ..................................................................................19 1.8.2 Role of muscle strengthening ................................................................................21 1.9 Thesis Rationale, Objective and Hypotheses ...................................................................25 1.9.1 Thesis rationale .........................................................................................................25 1.9.2 Objective ...................................................................................................................26 1.9.3 Hypotheses ...............................................................................................................26 Chapter 2: Methods.................................................................................................................27 2.1 Study Protocol .................................................................................................................27 2.2 Study Participants ............................................................................................................28 2.2.1 Inclusion criteria .....................................................................................................29 2.2.2 Exclusion criteria ...................................................................................................29 2.3 Study Intervention ............................................................................................................29 2.3.1 Phase 1 .................................................................................................................31 2.3.2 Phase 2 .................................................................................................................32 2.3.3 Phase 3 .................................................................................................................33 2.4 Data Collection ................................................................................................................34 2.5 Primary Outcome Measures ............................................................................................35 2.5.1 Hip muscle strength ...............................................................................................35 2.5.2 Self-reported hip pain and function ........................................................................36 2.6 Secondary Outcome Measures .......................................................................................37 2.6.1 Objective physical function ....................................................................................37 2.6.2 Hip pain .................................................................................................................38 2.6.3 Dynamic balance ...................................................................................................38 vii  2.6.4 Hip range of motion ...............................................................................................39 2.7 Other Outcomes ..............................................................................................................40 2.8 Data Synthesis/Analysis ..................................................................................................41 2.8.1 Sample size ...........................................................................................................41 2.8.2 Data management .................................................................................................41 2.8.3 Statistical analysis .................................................................................................42 Chapter 3: Results ..................................................................................................................43 3.1 Participant Demographics ................................................................................................43 3.2 Outcome Data .................................................................................................................45 Chapter 4: Discussion ............................................................................................................51 4.1 Interpretation of the Findings ...........................................................................................51 4.2 Study Limitations .............................................................................................................56 4.3 Clinical Implications and Future Directions ......................................................................57 References ..............................................................................................................................61 Appendix A: Informed Consent and Letters of Explanation ................................................69 Appendix B: Images of the Exercises....................................................................................74 Exercise Program – Phase 1 .................................................................................................74 Exercise Program – Phase 2 .................................................................................................80 Exercise Program – Phase 3 .................................................................................................85 Appendix C: Data ....................................................................................................................92 Hip Flexion Strength ..............................................................................................................92 Hip Abduction Strength ..........................................................................................................93 Hip Adduction Strength ..........................................................................................................94 Hip Extension Strength ..........................................................................................................95 Hip Internal Rotation Strength ...............................................................................................96 Hip External Rotation Strength ..............................................................................................97 viii  HOOS Questionnaire Subscales ...........................................................................................98 Appendix D. Exercise Diary .................................................................................................. 100 Appendix E: Permission for Images .................................................................................... 104     ix  List of Tables  Table 1. Demographic information ............................................................................................45 Table 2. Outcome measures .....................................................................................................47 Table 3. Adherence and diary information .................................................................................49 Table 4. Duration of time in each exercise phase ......................................................................50                x  List of Figures  Figure 1. Image of hip anatomy. ................................................................................................. 6 Figure 2. Image of hip impingement. .......................................................................................... 9 Figure 3. Graph of muscle weakness. .......................................................................................21 Figure 4. Image of strength testing. ...........................................................................................36 Figure 5. Image of Star Excursion Balance Test. ......................................................................39 Figure 6. Participant flowchart. ..................................................................................................44    xi  List of Abbreviations ACSM American College of Sports Medicine ADL activities of daily living AP anteroposterior BMI body mass index BW body weight cm centimeter GRF ground reaction force FABER hip flexion, abduction and external rotation FADIR hip flexion, adduction and internal rotation FAI femoroacetabular impingement HHD handheld dynamometer HOOS Hip disability and osteoarthritis outcome score Ht height ICC interclass correlation coefficient IHOT12 International hip outcome tool Kg kilogram Kg/m2 kilogram per meter squared  MABLab Motion Analysis and Biofeedback Lab mHHS modified Harris Hip Score MIC minimal important change xii  MVC maximal voluntary contraction MRI magnetic resonance imaging Nm Newton meter NRS Numerical rating scale NSAIDS Non-steroidal anti-inflammatory drugs OA Osteoarthritis QoL quality of life RCT randomized control trial ROM range of motion RPE rating of perceived exertion SD standard deviation SDD smallest detectable difference SEBT Star excursion balance test SPSS Statistical Package for the Social Sciences TA transverse abdominus TFL tensor fascia lata THA total hip arthroplasty TKA total knee arthroplasty UBC University of British Columbia VGH Vancouver General Hospital WOMAC Western Ontario and McMaster Universities osteoarthritis index  xiii  Acknowledgments I am very grateful to have this opportunity to complete this Master’s degree. The vast amount of support that everyone has provided me throughout these past couple years has been incredible.  Thank you to my supervisor Dr. Michael Hunt. You have always challenged me to be an independent thinker and problem solver, yet were there to lend a hand when I needed it most. You have helped me become a more efficient and organized person as I continue to learn from your example. Thank you for guiding me on this journey and for becoming a good friend.  Thanks you to my advisory committee Dr. Kay Crossley and Dr. Michael Gilbart. Without the two of you this project would never have been completed. Thank you Kim Lowe for putting up with my endless amounts of emails and helping enrol our study participants; which was no easy task. I would like to thank my friends and colleagues in the MABLab and Garland lab. Coming to work every day wouldn’t be as much fun without you guys. I’d like to give thanks to Chris Cochrane for always making time to help during data collection; even if that meant working in the early evening.  Thank you to the Department of Physical Therapy and the funding resources they made available to make paying for grad school slightly less painful. Thank you to my incredible wife. Judit, you have always been there for me; to celebrate my accomplishments or to support me during my failures. The strength of your support and love cannot be matched and I am truly lucky to have you by my side. Finally, thank you to my amazing family. I am incredible lucky to have such supportive parents (including Kevin) and the best brother I could ask for. Without my parents I would have never been able to accomplish this. Dad, you’ve continuously challenged me to do my best, whether it was at school or on the soccer pitch. Mom, you’ve always believed in me and encouraged me to find work I enjoy doing. And thank you to Brysen for keeping me sane. Our game sessions online have allowed me to step back from reality to enjoy some quality time together, even if we’re 2000 km apart. I love you all very much.        Jerrad Guenther Vancouver, October 23, 2014  1  Chapter 1: Introduction and Background  1.1 Overview of Femoroacetabular Impingement Femoroacetabular impingement (FAI) is a pathomechanical hip condition characterized by abnormal contact between the acetabulum and femoral head/neck junction 1. FAI is a recently characterized condition typically found in active, young and middle aged adults 2 and is thought to be a precursor to the development of hip osteoarthritis (OA) 1,3. Individuals with FAI commonly experience physical impairments that include limited range of motion (ROM) 4, muscle weakness 5,6 and altered movement biomechanics 7,8.  1.2 Etiology of FAI Currently, the direct cause of FAI is unknown; however researchers hypothesize that physical stresses including trauma to the hip joint and vigorous sports during growth and development, 9 and genetics 10 represent potential sources of disease development. High impact activities during bone maturation could be a reason for its development. In 2014, Agricola et al. confirmed these hypotheses with the first prospective study assessing the development of cam impingement. They found that cam type deformity (see section 1.5) is gradually acquired during skeletal maturation in elite youth soccer players 11. FAI occurs as a result of abutment between a widened femoral neck and a decreased offset at the head-neck junction (cam impingement), or 2  an abnormally shaped or oriented acetabulum (pincer impingement) 12. The persistent abnormal contact between the femoral neck and the acetabulum causes damage to the articular cartilage of the hip and labrum, leading to hip pain and dysfunction 1. The repetitive forces during sports activities and activities of daily living such as walking are major sources of microtrauma and irritation in the hip in this population. As a consequence of this recurring irritation, the bone compensates by ossifying and creating excess bone volume on the site of contact in accordance with Wolff’s Law 1. Further, the cartilage can compress due to repetitive movements at the hip joint leading to irreversible chondral damage that can progress and result in a degenerative disease 13,14. In addition, the newly formed osseous prominence can cause excess friction and stress the labrum, which may also lead to a tear or detachment of the labrum. Though FAI morphology usually progresses gradually, due to the aforementioned degeneration, FAI is thought to be an underlying cause of OA of the hip 1,3.  Evidence of a genetic risk factor comes from Pollard et al. 10. In their cross-sectional study, they found that siblings of patients with evidence of cam impingement are 2.8 times more likely to have a cam abnormality compared with the patients’ spouses 10. However, siblings are commonly raised in the same environment and participate in similar sporting activities during growth, making it difficult to distinguish genetic from environmental influences. Although some genetic involvement is likely, currently there is not enough evidence to fully support this claim 15.  FAI can occur unilaterally or bilaterally. However if the symptoms are present in both hips, one side is often more symptomatic. FAI can occur secondarily due to a variety of pre-existing conditions including slipped capital femoral epiphysis 16, Perthes 3  disease 17 and femoral neck fractures 18. However, for the vast majority of people with FAI, the impingement is primarily due to abnormal morphology of the femoral neck and/or acetabulum.  1.3 Epidemiology of FAI In 1965, Murray was the first to report on the concept of what is now called FAI 19. He investigated the radiographs of 50 healthy adults and 200 individuals with OA in the hip to determine if the development of hip OA was primary or secondary due to anatomical variation. Murray’s findings showed that even in asymptomatic individuals, a tilt deformity was present, which is defined as an abnormal ratio of the femoral head-neck offset. From analysis of the radiographs it was believed that the minor anatomical abnormalities of the hip results in a less efficient articulating surface, thus causing premature degeneration of the joint. Therefore, he speculated the tilt deformity is a contributing factor in the development of hip OA. In 1974, Stulberg and Harris 20 expanded on Murray’s initial report by defining the decreased femoral head-neck offset in patients with FAI. They coined the term pistol-grip deformity, as the proximal end of the femur resembled the grip of a pistol on radiograph. Only in the past decade have Ganz and colleagues used the term cam impingement, and the amount of research into FAI has rapidly increased 1. In the past, this pathomechanical condition often went undiagnosed. Individuals with FAI often experienced deep hip or groin pain and labral tears, which went unresolved and improperly treated 21,22. Repairing a torn labrum was a common treatment among active 4  individuals, however this did not serve as a long term solution to the underlying cause of the labral tear 21.   Current research and clinical findings indicate that FAI typically presents itself in active, young and middle aged adults (between ages 20 and 50 years) 13. However, a recent study reported the development of FAI morphology in paediatric (as early as 10-12 years of age) and adolescent populations 23. Currently, the diagnosis of FAI is based on the co-existence of radiographic evidence, patient history and clinical signs 4. Historically, men were thought to represent the vast majority of cases of FAI, and published reports indicated prevalence rates of cam impingement as high as 24.7% in young, active males and only 5.4% in females 23,24. However, Clohisy et al. investigated a large cohort of 1076 patients undergoing surgery for FAI and found conflicting results among those with all types of hip impingement 25. In this large cohort, 55% of patients were female and 45% male, with a mean age of 28.4 years 25. This is in contrast to previous studies that showed that FAI was more common in males. One explanation for this may be that in recent years, there has been a large increase in athletic participation by females in North America, specifically young and adolescent females, which may explain the increased prevalence of FAI in females found by Clohisy et al. Since the female athletic population is growing, future studies are needed to determine if these results are representative of the population of patients with FAI. Indeed, other studies have shown a strong association between sports and deterioration of the hip is reported: 50-70% of people that develop FAI participate in sports, with 29-30% of those individuals being elite athletes 26,27. Nevertheless, there is an increased prevalence of FAI among both males and females in recent years. Therefore, treatment studies are of 5  the utmost importance as researchers and clinicians attempt to resolve this specific hip pathology.  1.4 Structure and Function of the Hip The femoroacetabular joint is a ball-and-socket joint comprised of the pelvis and the femur, capable of three degrees of freedom 28. The pelvis is made up of three bones that include the ilium, ischium and pubis, which are fused together to create a cup-shaped structure called the acetabulum (socket). The acetabulum is lined by a thin layer of hyaline cartilage which articulates with the head of the femur. Articular hyaline cartilage also covers the surface of the femoral head to provide smooth contact with the acetabulum. In a healthy, impingement-free hip, the spherical shape of the femoral head provides an efficient surface for the acetabulum to pivot around (Figure 1). Fibrous and synovial membranes surround the joint by attaching to the rim of the acetabulum and the femoral neck. The synovial membrane produces synovial fluid inside the joint space which keeps the joint lubricated and reduces the amount of friction during movement. The fibrous capsule along with four ligaments provide stability by strengthening the joint and help to maintain synovial pressure inside the joint. The three extracapsular ligaments including the iliofemoral ligament, pubofemoral ligament and ischiofemoral ligament provide some joint stability and limit excess rotation and hyperextension at the hip joint. The labrum attaches around the rim of the acetabulum and creates a continuation of the articular cartilage. Thus, it deepens the socket, increases the surface area for the head of the femur to articulate with, and aids in maintaining the synovial pressure and distributing the load evenly across more of the joint. The labrum in a 6  healthy hip is thought to act as a cushion and reduce the amount of excess load and wear on the articular cartilage of the acetabulum and femoral head. Figure 1. Image of hip anatomy. A healthy human hip joint is shown here. The femoral head articulates with the acetabulum while the labrum helps to deepen the socket and maintain pressure in the joint. Reproduced with permission from OrthoInfo. ©American Academy of Orthopaedic Surgeons. http://orthoinfo.aaos.org.  1.4.1 Muscles of the hip The muscles of the hip have a multitude of functions. In particular, they provide stability for the hip joint and initiate movement for dynamic weight bearing activities including walking, running and squatting. Movements of the hip include flexion (bend), extension (straighten), abduction (take the leg away from body), adduction (bring the leg towards the body) internal rotation (rotation of the femur inwards) and external rotation (rotating the femur outwards). There are 22 muscles that the cross the hip joint and are often grouped as synergistic muscles. The primary movers in flexion of the hip are 7  iliopsoas which is a combination of iliacus, psoas major and psoas minor. Tensor fascia lata (TFL), rectus femoris, pectineus, adductor longus and adductor brevis also contribute to the synergy as hip flexors. On the posterior side, semitendinosus, semimembranosus and biceps femoris comprise the hamstrings. These muscles along with gluteus maximus and the long head of adductor magnus function primarily in extending the hip.  In hip abduction, the primary movers include gluteus medius, gluteus minimus and TFL which also help stabilize the pelvis during single-limb stance. Piriformis, oburator internus, superior and inferior gemelli are also synergists that assist in abduction of the hip. Adductor longus, adductor brevis, adductor magnus and gracilis comprise the muscle group responsible for adduction of the hip. Internal rotation (medial rotation) of the hip when flexed is produced primarily by the anterior fibres of the gluteus medius and gluteus minimus; however, TFL does assist the movement as well. External rotation (lateral rotation) of the hip is produced by the activation gluteus maximus, gluteus medius and a combination of smaller muscles which include obturator externus, obturator internus, quadratus femoris and sartorius. When the hip is extended, gemellus superior, gemellus inferior and piriformis contribute to lateral rotation of the hip.   1.5 Types of FAI Two main types of FAI will be described, cam and pincer lesions, displayed in Figure 2. It should be emphasized that these two disease patterns can occur alone, yet they often occur together, which is known as mixed (or combined) impingement, where 8  components of both cam and pincer impingement co-exist 29,30. People with mixed impingement FAI may have one type of impingement that predominates, or both types may contribute equally 31. In a recent epidemiological study on a large cohort of 1076 individuals with FAI (55% female), researchers reported that 47.6% of hips had a diagnosis of cam FAI, 44.5% had combined cam and pincer FAI, and 7.9% had pincer FAI 25. In addition, the coexistence of labral damage and FAI is quite high. An imaging study by Kassarjian et al., 32 analyzed the prevalence of labral tears and acetabular cartilage defects in those with FAI. Of the 40 participants, 100% displayed an anterosuperior labral tear and 95% displayed anterosuperior acetabular cartilage damage on MRI 32. According to other studies, about 90% of individuals with with labral pathology have underlying structural abnormalities in femoral and/or acetabular morphology 33,34. These findings confirm that labral tears and acetabular cartilage defects are very high in those with FAI.  9  Figure 2. Image of hip impingement. Over-coverage of the acetabulum on the superior edge is representative of pincer impingement (left). A bony prominence on the anterosuperior head-neck junction of the femur creating an abutment of the acetabular rim is representative of cam impingement (right). Reproduced with permission from OrthoInfo. ©American Academy of Orthopaedic Surgeons. http://orthoinfo.aaos.org.  1.5.1 Cam impingement Cam lesions are common in young active men. The cam impingement is a nonspherical portion of the anterior-superior femoral neck abutting against an acetabular rim. This effects of the abutment is most evident during flexion and internal rotation 35, and causes excess friction of the acetabular cartilage with damage to the labrum and the subchondral bone. During repetitive loading at the site of impingement, the bone tries to compensate by forming osseous prominences creating an insufficient convex surface, which in turn increases the severity of impingement 1. This decreased convexity, known as a pistol-grip or tilt deformity, results in a jamming of the femoral head into the morphologically normal acetabulum during wide ranges of motion 18,36. The extra bone volume can cause unwanted compression and shear forces on the labrum and acetabular cartilage 14,30. This can lead to separation of the cartilage from 10  the antero-superior aspect of the acetabulum and tearing of the labrum itself, which can gradually lead to osteoarthritis of the hip 37,12,36. During imaging, characteristics of cam impingement include large alpha angles (a measurement taken to quantify the abnormal sphericity of the femoral head and the neck junction 38), an osseous development on the femoral neck and acetabular cartilage lesions 39. An alpha angle greater than 50.5 degrees is often indicative of cam morphology 38, and greater alpha angles substantially increase the risk for OA 3. However,  it is important to note that participants showing radiographic signs of cam morphology will not always have cam impingement 3. The cam impingement affects the person’s ability to flex and internally rotate their hip; the osseous prominence causes impingement reducing the amount of hip flexion. Functionally, this type of impingement has implications as many ADL and sports require the individual to bend at the hips, for example putting on a pair of socks, sitting in a low chair or squatting and maintaining an athletic stance.  1.5.2 Pincer impingement Pincer lesions are common in middle-aged active women. They occur through repeated contact between a normal femoral head-neck junction and an over-coverage of the acetabulum 1,35. This over-coverage or deepening of the acetabulum is called coxa profunda if the over-coverage is general. When the over-coverage is only anterior and local (not creating an over-coverage over the entire femoral head) this is called acetabular retroversion 1,30. Coxa profunda can occur from overgrowth of the anterior edge and acetabular retroversion can occur with a slight backwards tilt of the acetabulum 31. Additional characteristics that result in the same effect are an overhang 11  of the acetabular rim 36 or increased pelvic tilt 40. These physical characteristics caused by repetitive microtrauma result in degeneration of the labrum, ossification of the acetabular rim, and deepening of the acetabulum 29. Along with the aforementioned characteristics of pincer impingement, posteroinferior acetabular cartilage lesions often develop and are significantly larger on imaging in individuals with pincer FAI 39. Individuals with pincer impingement do not seem to exhibit the reduced hip flexion as seen in those with cam impingement 41.  1.6 Diagnosis of FAI  The diagnosis of FAI is based on clinical evaluation of the patient and evaluation of magnetic resonance imaging (MRI) and radiographic imaging of the hip.  1.6.1 Clinical presentation  Individuals with FAI commonly begin to have symptoms insidiously, typically after bouts of vigorous exercise or after minor trauma 42. Evaluation of the patient’s history often reveals pain in the anterior and lateral regions of the hip or groin area. It is not uncommon for patients to also mention discomfort or pain in the buttocks, lower back or over the greater trochanter. Due to the painful symptoms, FAI limits the ability of individuals to exercise and causes restriction and discomfort during activities of daily living 23,30. For example, walking is the most common activity of daily living, and is rated as ‘moderately difficult’ or ‘unable to perform’ by a majority of patients with FAI 27,43. In addition, FAI commonly presents itself as a dull ache, or pain inside the hip joint during 12  simple activities of daily living including putting on socks or getting in and out of a low vehicle 44. Physical activity will often exacerbate the symptoms, especially during movements that require a large range of motion, specifically in hip flexion and internal rotation (ex. pivoting). Conversely, sitting for long periods of time can also cause pain and discomfort due to prolonged time spent the hips spend in a flexed position 1,45.  1.6.2 Physical examination During the physical evaluation, it is common for patients to indicate where the pain is originating from by creating a “C” shape with their fingers and thumb placed over the trochanteric region of the hip. When this is performed, patients display a positive C-sign. A thorough physical evaluation follows, and includes the physician performing an anterior impingement test where the physician passively flexes, adducts and internally rotates the patient’s hip while they are lying in supine (FADIR). The test is positive if the patient experiences pain while placed in this position and displays restricted range of motion. Studies have reported that 90%-99% of individuals with a positive impingement test are later confirmed to have FAI, indicating high sensitivity of this measure 43,46. The posterior impingement test is also used during physical evaluation. The physician will have the patient in a supine position while passively moving them into hip flexion, abduction and external rotation (FABER). The physician will measure the distance from the inferior aspect of the knee to the height of the table. A positive test showing pain during this movement is not necessarily specific to patients with FAI but also common among golfers whom experience low back pain 47. However,  lateral hip pain in combination with an increased height or distance of the lateral aspect of the knee to the 13  table while in the FABER position can be indicative of FAI patients 44. Philippon et al. reported that this positive impingement may not have any direct mechanical consequence in people with FAI, yet the FABER distance did improve after surgical treatment for FAI 43. These contradicting results show that future research is needed to determine the validity of the FABER test in detecting FAI. A standardized assessment is needed during the initial assessment for FAI. One suggested component that should be included in the physical evaluation is an objective measure of muscle strength. Importantly current research has shown significant hip muscle weakness in those with FAI when compared to those who do not have FAI 5.  1.6.3 Radiographic assessment  A key part of the confirmation of FAI is the assessment using radiographs. According to an experienced orthopaedic surgeon (M. Gilbart, personal communication, November 7, 2013) radiographic assessment should include an anteroposterior (AP) view of the pelvis, along with an AP and lateral view of the hip. The AP view of the pelvis is used to determine a pincer impingement, and the AP, lateral and Dunn view (AP view with the hip flexed at 45 degrees and abducted 15-20 degrees from midline) are used to detect lesions on the head/neck of the femur for cam impingement. If an abnormal acetabulum is present (retroversion, coxa profunda), it will be evident from the AP view. If alpha angle is present, it will be clearly visible from the Dunn view. Notlizi and colleagues reported the alpha angle in normal hips measured between 42 and 47 degrees compared to 65 to 70 in impingement, and 55 degrees was used as a cutoff for FAI. Values from 50.5 and higher have been suggested to predispose the hip to a cam 14  impingement 38. It is important to note that FAI anatomy as defined by radiographic criteria is common in the general population, with reports as much as 30% of asymptomatic people having radiographic FAI 24. If FAI is suspected from a patient’s history, their positive impingement test and from radiographic evidence, they are usually sent for MRI. The MRI can detect further soft-tissue abnormalities including labral tears and chondral damage of the hip. The benefits of imaging for those with FAI will be explained further in the following section.  1.6.4 Imaging in FAI Orthopedic surgeons have the ability to perform less invasive surgeries as advanced imaging methods are used to classify the hip condition. Imaging techniques including x-ray, magnetic resonance imaging (MRI) and computerized tomography (CT scan) are all useful in defining the pathological anatomy contributing to FAI and can help the orthopedic surgeon make treatment decisions. Magnetic resonance imaging assesses labral tears, chondral lesions, femoral version, and the surrounding soft tissue. Kennedy and Rosenfeld 48 report the importance of understanding and recognizing the fundamental features of FAI as seen using multiple diagnostic imaging techniques. When combined with an appropriate clinical history and physical examination, early diagnosis and appropriate intervention can be made 48. Early diagnosis is particularly critical because the length of time that symptoms are present for has a profound impact on surgical success rate 49. In one study, 525 patients were divided into three groups according to the duration of hip pain prior to undergoing hip 15  arthroscopy: group 1, less than six months; group 2, six months to three years; group 3, greater than three years. The requirement for subsequent revision hip arthroscopy or arthroplasty on the same side was 4 % in group 1, 11 % in group 2 and 13 % in group 3 49. These results show that patients that underwent hip arthroscopy sooner after symptom presentation were less likely to need a subsequent revision. The effects and efficacy of surgical treatment and conservative treatment will be discussed in the subsequent sections respectively.  1.7 Treatment for FAI 1.7.1 Surgical treatment  FAI has recently gained more clinical prominence. As clinicians and people with the impingement have become more conscious of the condition and of treatment options, many individuals have been able to resume sports activities and activities of daily living. This exposure has created more awareness about FAI and possible methods to help treat this disorder 31. With the addition of this knowledge, surgery is more common and has remained the primary treatment option for people with FAI.  Surgery is intended to relieve any mechanical impingement between the femoral head and the acetabular rim as well as treat any residual injuries that may be present, thus improving the pain-free range of motion of the hip 14. Depending on the preferred surgical method of the orthopedic surgeon, the patient undergoes open surgical dislocation, arthroscopic surgery or a combined method. Arthroscopic surgery has become a common operation for FAI as this technique minimizes damage to the soft 16  tissue by only having to make small incisions 50. The surgical technique involves performing an acetabular osteoplasty, or ‘rim trimming’ for individuals with pincer FAI. The labrum is then reaffixed to the anterior acetabular rim using sutures and anchors. The cam FAI is managed by performing a femoral osteochondroplasty, which involves shaving and removal of the impinging bone.  Research shows that arthroscopic surgical treatment for FAI can result in moderate improvements in range of motion 28, physical function as measured on the Western Ontario and McMaster Universities OA Index (WOMAC) 51, and quality of life (QoL) 52. Specifically, Papalia et al. reported that arthroscopy significantly improved hip flexion, from 111.2° at baseline to 119.9° postoperatively, and internal rotation at 90° of hip flexion from 11.5° to 23.9° 53. Gedouin et al. reported that physical function scores as measured by the WOMAC significantly increased with a mean improvement of 22.7 points 51. Malviya et al. collected modified Harris Hip Scores (mHHS) which were translated using the rosser index matrix (a table that rates observed disability and subjective distress of a patient’s condition) to determine QoL. Of the 621 participants that underwent arthroscopy for FAI, 77.6% reported improved QoL, 14.4% reported no change, and 8.9% reported deteriorated QoL at a 1 year follow-up visit. Despite some positive findings, a systematic review including 23 studies showed that surgical treatment failure requiring hip replacement surgery occurred in about 4% of patients within 1 year 51, 11%  after 5 years 54, and 30% overall, at various time points 55. In a 2012 review, researchers calculated the direct mean costs of hip arthroscopy which averaged almost $12,000 US dollars 56. This highlights the need for improving patient outcomes to reduce the need for revision. Non-steroidal anti-inflammatory 17  medication, core strengthening, and physical therapy are common types of conservative treatment for individuals with various hip pathologies that may help improve patient outcomes. Currently, no muscle strengthening program is outlined for FAI in the literature.    1.7.2 Conservative treatment Despite the preference for conservative management of FAI prior to surgery, there is very little published data detailing outcomes from conservative treatments in this patient population. Indeed, only one study – published in 2011 – exists in this regard 57. They reported that the goal of conservative therapy is to reduce painful symptoms and avoid further joint damage to the hip without a need for surgery. In an attempt to achieve these goals, they investigated the effect of conservative therapy in patients with FAI, using activity modification and non-steroidal anti-inflammatory drugs over a two-year period. Twenty-seven males and 10 female participants (mean age 33 ± 5 years) underwent four stages of conservative treatment. The first phase involved avoidance of excessive physical activity. Additionally, anti-inflammatory drugs (diclofenac 50 mg, twice a day) were taken as needed during the first 2-4 weeks. The second phase included 2-3 weeks of physical therapy which consisted of hip stretching exercises. In the third phase, participants were instructed to adapt their movement and perform ADLs with minimal discomfort. The fourth and final phase included modification of ADLs to avoid positions that involve flexion, adduction and internal rotation. This treatment resulted in symptomatic improvement in pain, although no improvement in range of movement was noted 57.However, even though this study showed improvements in pain 18  via two self-reported questionnaires, the primary outcomes were not defined. Additional conservative treatments with defined primary outcomes and objective measures are needed to assess the efficacy of conservative treatment. Yazbek et al. investigated a non-surgical treatment case series in 4 people with acetabular labral tears. Appoximately 90% of acetabular labral tears are associated with underlying FAI 33. The investigators evaluated ROM, pain, level of function assessed with the Lequesne hip score, and hip muscle strength using handheld dynamometry. The treatment protocol consisted of 3 phases, phase 1 involved correcting abnormal movements to reduce hip pain, with phases 2 and 3 focusing on muscle strengthening, range of motion and balance training. The muscle strengthening program included 3 sets of 10 repetitions of standing hip flexion and extension, standing hip abduction and adduction using resistance bands, lunges, shuttle machine, and flexion-extension on a chair. In addition, 3 sets of sidestepping with resistance bands and single-limb squats were performed in a 1-minute time period. Three of the 4 study participants had total pain relief as determined by the visual analog scale. All 4 participants showed improvement in muscle strength including hip flexors (1%-39%), abductors (18%-56%), and extensors (68%-139%). This study clearly defined its outcomes and included objective measures (ROM and strength); however, according to the MRI results, only one of the four participants showed FAI morphology. Further, a sample size of four participants is too small to draw firm conclusions, regardless if the labral tears were secondarily due to FAI. Thus, the quality of research and level of evidence for these initial conservative treatments for FAI is low.  19  In a recent review paper on current concepts of FAI, it was advised that conservative treatments for people with FAI include activity modification, anti-inflammatory medication, abductor strengthening, and hip-motion exercises 58. Multiple studies on management of FAI suggest that improving core strength and hip strength while avoiding excess ranges of motion could be beneficial for managing symptoms 42,59. Specifically, physical therapy focused on muscle strengthening, patient education and avoidance of extreme ranges of motion could alleviate symptoms. Proprioception activities is also recommended; this training can improve sensory–motor control by using standing balance, wobble boards and BOSU balls 58. As stated above, to the author’s knowledge, there are very few studies assessing conservative therapy for people with FAI, and thus there is a lack of high quality research on conservative therapy options. The rapid influx of FAI research in the past decade has provided more information regarding functional limitations of those with FAI. Thus, conservative treatments including standardized exercise programs targeted to improve participants’ level of physical function and pain are lacking. Specifically, there is an absence of treatments to improve physical function before surgery.  1.8 Role of Muscle Strength in FAI 1.8.1 Hip muscle weakness in FAI Hip muscle weakness is prevalent in those with FAI, and can lead to abnormal joint loading which causes pain and dysfunction during dynamic weight-bearing 20  activities such as walking. This can be due to a combination of causes including muscle inhibition, altered neuromuscular function due to pain or restriction, and compensatory gait mechanics over a prolonged period of time. There is very little published data comparing hip muscle strength in people with and without FAI. However, a limited number of studies support the notion of widespread muscle weakness in people with FAI 5,6. Casartelli et al. assessed hip muscle strength of 22 individuals with FAI and 22 controls matched for gender, age and body mass and showed that those with FAI exhibited significantly lower maximal voluntary contraction (MVC) strength during hip flexion (26% weaker), abduction (11% weaker), adduction (28% weaker) and external rotation (18% weaker) 5. The mean hip muscle strength in people with FAI across all movements was 16% less compared to healthy controls. Isokinetic dynamometry was used to measure isometric muscle strength for hip flexion and extension, and handheld dynamometry was used for hip abduction, adduction, internal rotation and external rotation. In this study, participants with FAI reported hip joint pain during measurement of hip strength, in contrast to controls, who reported no pain 5, and this may have influenced the measurements of strength. A more recent study conducted by our research group has confirmed these findings and showed additional weakness of the hip extensors and internal rotators (Figure 3). Specifically, in a cohort of 30 people with FAI and an equal number of people without, we showed that those with FAI had significantly lower MVC strength in hip flexion (25% weaker), abduction (18% weaker), adduction (13% weaker), extension (18% weaker), internal rotation (26% weaker) and external rotation (14% weaker) (Figure 3) 60. All six isometric muscle strength measures were collected using handheld dynamometry by a trained assessor during one session. 21  It is evident that those with FAI exhibit lower isometric hip strength compared to those without impingement. This highlights the need for strengthening the muscles of the hip in people with FAI.  Figure 3. Graph of muscle weakness. Isometric hip muscle weakness is shown in all six movements for people with FAI (squares) compared to those without (diamonds).  1.8.2 Role of muscle strengthening Hip muscle weakness in people with FAI can contribute to joint pain, and decreased physical function. It is suggested that improving active muscle control and joint stability may help reduce joint pain, improve function and possibly slow joint damage for individuals with hip pathology 61. Given that muscle strengthening targeting areas of muscle weakness known in FAI prior to surgery may improve patient strength, pain, and function, and consequently, patient outcomes after surgery 62 identification of 22  strategies to improve muscle strength in people with FAI is an important clinical and research objective.  Fortin et al. reported that those with higher function before surgery continued to have higher function and less pain after surgery compared to those with lower function in a total hip arthroplasty (THA) cohort 62. By strengthening the muscles around the hip, hip stability may improve, thus improving posture and reducing the abnormal stresses the hip joint has to endure. Stronger muscles can also absorb more of the load at the hip joint and allow for a higher level of functioning. Pre-habilitation (exercises before surgery, as opposed to just after surgery) muscle strengthening programs are known to improve strength, pain and function in other musculoskeletal pathologies. Physical therapy or muscle strengthening programs should take into consideration: athletic demands, restriction in range of motion, and an objective measure to reliably detect weakness in muscle strength testing 58. The physical therapy program must not only improve strength of the hip abductors and all musculature surrounding the hip joint, but also emphasize proper muscle activation and postural balance 58. Improvements in posture and core strength may create subtle changes in the position of the lumbar spine and pelvis to avoid impingement and create stability during dynamic activities 58. However, there is currently no literature demonstrating the effectiveness of strengthening interventions with regard to improving physical function or altering the natural pathway of joint degeneration in people with symptomatic FAI 58. In a study of individuals with knee osteoarthritis awaiting high tibial osteotomy, those who participated in a strength training program showed improvements in strength and function compared to a control group 63. The strength training program consisted of 23  facility based supervised exercises 3 times per week for 12 weeks. Training sessions included isokinetic concentric quadriceps and hamstring exercises. Participants in completed 3 sets of 10 repetitions of isokinetic knee extension and flexion at 60 degrees/second, 90 degrees/second and 120 degrees/second, followed by 3 sets of 15 repetitions at 180 degrees/second where they exerted themselves maximally 63. Post training knee extension strength was 170.5 (38.0) Nm compared to 132.2 (39.6) Nm at pre training. Post training knee flexion strength was 111.5 (17.4) Nm compared to 79.3 (28.2) Nm at pre training. The significant increase in pre-surgical muscle strength demonstrates the ability for patients to improve their lower limb muscle strength while awaiting surgery. For patients awaiting THA, a preoperative exercise intervention improved muscle strength and self-reported function with significant pre-operative differences between exercise and control groups 64. When comparing baseline outcome values to post-intervention (pre-operative) outcome values, the THA  exercise stabilized their WOMAC function scores and improved their muscle strength by 18% (measured via one repetition maximum leg press), whereas the controls had a decrease in function and no change in strength. In this randomized trial, participants in the exercise group preformed water and land based exercise 3 times per week for 6 weeks prior to surgery. During the first 3 weeks participants performed single planar movements while standing in chest deep water. The following 3 weeks included cardiovascular, strength and flexibility components. The strength training activities were performed in 2 sets and 8-12 repetitions which included seated row, chest press and leg press using resistance training machines; biceps and triceps exercises using free weights; and shoulder and 24  abdominal exercises using bodyweight. The improvements in strength and self-reported function for participants with THA demonstrate the efficacy of an exercise/strength training intervention for those with a similar pathology to FAI.  In another pre-post study, people with osteoarthritis of the knee were enrolled in a pre-operative exercise program before undergoing total knee arthroplasty (TKA) 65. The exercise program consisted of nine lower body resistance training exercises including squats and the use of resistance bands for hip flexion and extension, hip abduction and adduction, knee flexion and extension, and ankle plantar flexion and dorsi flexion. The length of the intervention was not reported, however participants in the exercise group performed the exercises three times per week and completed on average 13 training sessions pre-surgery. At the post-exercise, pre-surgery assessment, participants in the exercise group significantly improved their functional performance, as measured using the sit-to-stand task. However, the other outcomes which included 6-minute walk task, time to ascend stairs and time to descend stairs and maximum knee extension strength did not reach statistical significance 65. This study included a comprehensive list of lower body exercises designed to improve muscle strength, pain and physical function, however only one specific measure of function significantly improved at the post-intervention, pre-surgery time point. An explanation for this might be that the strength training group only completed a mean of 13 exercise sessions (range: 4-23 sessions), which is equivalent to four weeks of training: slightly lower than the recommended amount to achieve significant strength increases 66,67. To-date, no studies have assessed the effect on muscle strengthening prior to surgery in FAI. Based on the results of similar programs in other pathologies, muscle 25  strengthening may alleviate symptoms and improve the muscle strength and functional mobility of those with FAI.  1.9 Thesis Rationale, Objective and Hypotheses 1.9.1 Thesis rationale It is widely believed that weak hip muscles lead to reduced hip motion and instability within the hip joint which can cause hip pain 61. More importantly, as indicated above, instability and altered joint contact forces in a hip with FAI may play a role in the early development of hip osteoarthritis 1. As a result, treatment approaches that can effectively restore muscle function and biomechanics to near-normal levels of hip function in an impinged hip represent an important component of overall clinical management. The average surgery wait times have been estimated by local clinicians to be between 6 and 9 months. During the time that patients are waiting for surgery, there is an opportunity to provide effective pre-habilitation in order to improve muscle strength, pain and function. Pre-habilitation programs in other populations have resulted in improved clinical outcomes 63-65, and if similar results in those with FAI can be achieved, pain and dysfunction may be reduced and surgical outcomes improved. No previous research exists on the efficacy of a muscle strengthening program available for those with FAI. This will be the first study to assess the effects of muscle strengthening on clinical measures in people with FAI.  26  1.9.2 Objective The objective of this study was to examine the effects of a pre-surgical hip muscle strengthening intervention on hip strength, pain and function in those with FAI.  1.9.3 Hypotheses 1) A 10-week hip muscle resistance training program will significantly increase hip strength in individuals with FAI.   Muscle strength of hip flexors will significantly increase  Muscle strength of hip extensors will significantly increase  Muscle strength of hip abductors will significantly increase  Muscle strength of hip adductors will significantly increase 2) A 10-week hip muscle resistance training program will significantly improve pain and function on the patient reported outcome questionnaire in individuals with FAI.  Hip pain will significantly improve on the Hip disability and Osteoarthritis Outcome Score subscale  Self-reported function will increase on the activities of daily living subscale of the Hip disability and Osteoarthritis Outcome Score questionnaire.   27  Chapter 2: Methods Roles of team members involved in study implementation: - Study coordinator (Jerrad Guenther) o Recruitment of participants after initial screening by orthopaedic surgeon o Data collection and analysis - Kinesiologist/trainer (Jerrad Guenther) o Administered the 10-week exercise program o Progressed the exercises and intensities - Research assistant (Chris Cochrane) o Measured isometric muscle strength for all participants during baseline and follow-up assessments   2.1 Study Protocol   This was a within-subject, pre-test – post-test intervention study examining the effects of a 10-week hip muscle strengthening program in individuals with FAI before hip surgery. Participants were be screened by Dr. Gilbart (orthopaedic surgeon) at the Joint Preservation Clinic at the University of British Columbia (UBC) Hospital. Study candidates exhibited definitive signs of FAI on magnetic resonance arthrogram, a positive hip impingement test as determined by the orthopaedic surgeon, and reports of anterior groin pain consistent with the pathology of FAI. All participants were patients with FAI on a waitlist to be scheduled for arthroscopic hip surgery. Interested 28  participants gave permission to be contacted by the study coordinator to arrange for baseline testing.  Baseline testing was performed at Dr. Hunt’s Motion Analysis and Biofeedback Laboratory (MABLab) at UBC and was comprised of measures to assess muscle strength and physical function, as well as completion of self-report questionnaires to assess pain and physical function. Participants then completed ten weeks of pre-operative home-based resistance training, 4 sessions per week. The home-based training program included 5 supervised sessions over the intervention in the multipurpose gym at UBC where the kinesiologist ensured proper form and technique, progressed the resistance of exercises and recorded the participants’ rating of perceived exertion (RPE). Following completion of the intervention, participants returned to Dr. Hunt’s lab for follow-up testing. All outcome measures except muscle strength were assessed by the study coordinator and in the same testing order. Muscle strength was measured by the lab’s research assistant to ensure the study coordinator/trainer had no bias on the participant’s strength results.  2.2 Study Participants As mentioned previously in section 2.1, the study participants were screened by the orthopaedic surgeon and only candidates with clinical and radiographic evidence of FAI and met the following additional criteria were eligible to participant in the study.  29  2.2.1 Inclusion criteria - Age 18 to 55 years - Clinical and radiographic evidence of FAI as determined by the orthopaedic surgeon (cam, pincer or mixed) - Able to travel to UBC for testing and training sessions  2.2.2 Exclusion criteria - History of significant lower body injuries or conditions other than FAI that would impair the measurement of hip function or hip strength  - History of significant neurological injury that affected walking  - History of avascular necrosis of the hip - Planned or previous lower limb joint replacement - Planned commencement of a strengthening program within ten weeks, or currently enrolled in an exercise program focused on strengthening the hip muscles  2.3 Study Intervention Participants enrolled in a 10-week hip muscle strengthening intervention. During this 10-week program, the participant progressed through three phases. Participants received a bilateral hip strengthening program consisting of 4-6 exercises per phase. 30  Hip flexors, abductors, adductors, extensors and internal and external rotation groups were targeted. The aim of the first phase was to facilitate optimal, pain free activation of key muscle groups, improve neuromuscular control and develop endurance. It was important to build a foundation of muscle strength in all movements of the hip during the first phase before progressing. During the second phase of the intervention, resistance was increased through the addition of weight cuffs or resistance bands. In the final phase of the intervention, the focus was on improving the performance of functional movements.   Participants performed these exercises at home four times per week (3 sets of 10-12 repetitions per exercise per session), which meets the American College of Sports Medicine guidelines necessary to show significant strength increases 67,68. Over the course of the intervention, each participant consulted with the kinesiologist a total of five times (once per week in weeks: 1,2,4,6, and 8) to ensure proper performance of exercises and safe progression of resistance. Exercise intensity was moderated by increasing the number of repetitions from 10 to 12 as necessary. Further, resistance bands and weight cuffs were also used to increase resistance. Varying levels of resistance for both the weight cuff and the resistance bands were carried in the multipurpose gym. These included multiple weights of cuffs (0.91kg, 1.36kg, 1.81kg and 2.27kg) and resistance bands of various tensions (red, green, blue and black). The RPE scale was used to determine the intensity of each exercise. Participants were asked to rate their level of exertion on the scale which ranges from 6 (no exertion at all) to 20 (maximal exertion). The RPE scale is recommended by ACSM to monitor exercise intensity during a workout. If the participants’ exercise RPE was below 10, the 31  kinesiologist increased the intensity by increasing the number of repetitions and/or amount of resistance. However, it was not mandatory for each specific exercise to reach an RPE of less than 10 before the exercise intensity was increased. Importantly, the kinesiologist and the participant kept an open dialogue regarding the difficulty of each exercise, and intensity was increased accordingly. In the end, the progression to each exercise phase was at the discretion of the kinesiologist.  2.3.1 Phase 1 In phase 1, participants performed five exercises (Appendix C). The aim of the first phase was to facilitate optimal, pain free activation of key muscle groups, improve neuromuscular control and develop endurance. These exercises were mostly single joint movements to build a foundation of muscle strength by ensuring proper muscle activation. Specifically, the exercises included bridging, an exercise for the deep core muscles also known as transverse abdominals, clamshells, a four point kneel with hip abduction, and a standing balance task on one leg. The purpose of bridging was to create a resisted hip extension movement to activate the gluteal muscles. Transverse abdominus (TA) was targeted as the participants performed a TA hold in supine while they lowered their heels to the ground (knees at about 45 degree angles). Clamshells were meant to target the hip abductor muscles along with the external rotators. The four point kneel was given to target the hip abductors as well. In this position, participants were on all fours, shifted their weight onto one knee and then engaged their abductors to move the limb laterally. If this movement created an onset of hip joint pain, lying hip abduction was performed instead. Finally, single leg standing balance was used to 32  target the participants balance. When standing on one leg for 60 seconds became less of a challenge, they were instructed to lift their heel off the ground. One final progression was to have participants close their eyes. This increase in difficulty also increases the amount of proprioception needed, since the visual feedback has been removed.   2.3.2 Phase 2 In phase 2, participants performed four new exercises that replaced the phase 1 exercises (Appendix C). During this phase of the intervention, the aim was to build on their foundation of muscle strength and to increase intensity of the exercises. In addition, changing the exercises continued to target the hip muscles of interest, reduce monotony and increase enjoyment. The exercises in this phase included clamshells with weight cuffs, standing hip extension with resistance bands, sidestepping using resistance bands and standing hip abduction with weight cuffs. Clamshells were the only exercise that carried over from phase 1. The weight cuff was included for all participants and fastened just above the knee. The weight of the cuff was dependent on their performance and level of exertion from the previous phase. Standing hip extension was included to target the hip extensors, specifically, gluteus maximus. Participants stood up tall, shifted their weight onto the standing leg, engaged their core and extended the lower limb backwards. The resistance band was fastened around the bottom of a chair or table and around the ankle of the participant. During sidestepping, the purpose was to activate the quadriceps and hip abductors. Participants slightly flexed their knees and hips while stepping sideways with their feet in parallel. The 33  resistance band was fastened around their ankles. Finally, standing hip abduction was performed while holding onto the back of a chair or table. Participants stood tall on one leg, while moving the other leg laterally. The weight cuff was fastened around the ankle. This exercise worked the hip abductors isometrically, concentrically and eccentrically.   2.3.3 Phase 3   Phase 3 included a total of six exercises, yet participants were told to alternate between two of the exercises, thus five exercises were performed per training session (Appendix C). The aim of phase 3 was to have the participants perform functional movements, some of which may not have been properly executed free of pain before the start of the intervention. The exercises in this phase included squats, lunges, multi-planar sidestepping with resistance bands, step ups onto a bench or step, single leg dead lift with a weight cuff in hand, and single leg hopping. Participants alternated between squats and lunges by only including one of the two exercises per session. Squats and lunges were included to target the gluteus maximus, quadriceps and hamstrings. Side-steps were carried over from phase 2, however forward and backward stepping was included to incorporate multiple directions of movement. This added multi-planar movement created for a more functional exercise. Step-ups were included to strengthening the quadriceps muscles: participants’ were instructed to use a step or bench that ensured no more than 90 degrees of hip flexion to limit potential impingement. Hamstrings and balance were targeted in the single leg dead lift. Again, caution was used during the depth of the dead lift to limit excessive hip flexion to ensure pain-free execution. Lastly, single leg hoping was included to instruct participants to 34  absorb the ground reaction force (GRF) with their muscles (quadriceps, hips and calves) to limit the amount of force directly applied to the hip joint.  The first training visit was arranged at their respective baseline testing session. All subsequent visits were arranged during the weekly visits. The first visit was approximately 60 minutes in length with subsequent visits lasting approximately 45 minutes. All training sessions were one on one and took place in the multipurpose gymnasium in the Department of Physical Therapy at UBC. Throughout the intervention, the participants filled out an exercise diary on a weekly basis to assess adherence, changes in treatment, changes in medication and to record any adverse effects (see section 2.7 below for description of these measures).  2.4 Data Collection Participants met the study coordinator at the MABLab on the 3rd floor of the UBC Hospital. Information about age, gender, whether symptoms were unilateral or bilateral and most symptomatic limb was collected. In addition, participant radiographic information including impingement type (cam, pincer of mixed), tonnis grade, alpha angle, centre edge angle and tonnis angle were recorded from a prior radiographic assessment visit at UBC Hospital. Study participants had all primary and secondary outcome measures tested during their baseline (pre-intervention) assessment as well as their follow-up (post-intervention) assessment.  35  2.5 Primary Outcome Measures 2.5.1 Hip muscle strength Maximum isometric muscle strength was assessed using handheld dynamometry (HHD) for the following hip muscle groups: flexors, abductors, adductors, extensors and internal/external rotators. To prevent any bias in the muscle strength results, a trained tester (research assistant), who had no involvement in the strengthening intervention, was used to assess muscle strength.  Flexion strength was assessed in supine with the hip and knee flexed at 90 degrees with the dynamometer placed about 5 cm proximal to the patella. Abduction and adduction strength was assessed in supine with the dynamometer placed on the lateral and medial femoral epicondyle, respectively. Extension strength was assessed in prone with the dynamometer placed about 5 cm proximal to the center of the knee joint. Internal and external hip rotation strength was assessed in high sitting with the hip and knee flexed 90 degrees and the dynamometer placed about 5 centimetres (cm) proximal to the lateral and medial malleolus (Figure 4). Participants’ were asked to inhale before the maximum voluntary contraction (MVC) and on the exhale to push against the dynamometer as hard as possible for 5 seconds. This was repeated 3 times for each muscle group and the largest force production for each movement was converted to a torque by multiplying by the lever arm distance, then normalizing to body mass (Nm/kg).  Handheld dynamometry is a reliable and valid method for testing hip strength in athletes 69,70, and also a shown to have good to excellent reliability in people with hip 36  OA 71. Pua et al. investigated the intrarater test-retest reliability of hip muscle strength measurements using HHD in people with hip OA. They reported interclass correlation coefficients (ICC) of 0.87 for flexors, 0.97 for extensors, 0.84 for abductors, and 0.98 for both internal and external rotators. Test-retest reliability of our strength measures also showed good-excellent reliability as determined from a sub-sample of the first 12 study participants. ICCs in our population were 0.89 (95% CI: 0.53, 0.97) for flexors, 0.84 (95% CI: 0.43, 0.95) for extensors, 0.86 (95% CI: 0.54, 0.96) for abductors, 0.94 (95% CI: 0.79, 0.98) for adductors, 0.90 (95% CI: 0.66, 0.97) for internal rotation and 0.69 (95% CI: -0.65, 0.91) for external rotation. Figure 4. Image of strength testing. Participant positioning during isometric hip muscle strength assessed using handheld dynamometry. Hip movements pertain to flexion (A), extension (B), abduction (C), adduction (D), internal rotation (E), external rotation (F).  2.5.2 Self-reported hip pain and function Self-reported hip pain and function was assessed using the, Hip disability and Osteoarthritis Outcome Score (HOOS). The HOOS was developed to assess symptoms, pain, function with ADL, sports/recreation function and QoL of middle-aged to older adults with and without hip OA. For the purpose of this study all 5 subscales were scored with the primary focus on HOOS pain and HOOS ADL. The questionnaire is a 40 item questionnaire and each 37  question is answered using a five point Likert scale (for example: none, mild, moderate, severe, and extreme). A score is calculated for each of the five subscales where 100 equals no symptoms, and 0 equals extreme symptoms. Test-retest reliability coefficients were reported as ICCs for people with FAI in each of the five subscales 72. The ICC for pain was 0.95 (95% CI: 0.90, 0.98), for symptoms was 0.90 (95% CI: 0.80, 0.95), for ADLs was 0.96 (95% CI: 0.88, 0.98), for sport/rec was 0.84 (95% CI: 0.67, 0.93) and QoL was 0.92 (95% CI: 0.84, 0.96)72. The HOOS is a valid, reliable, and responsive disease-specific self-report instrument and has been used in many studies for people with hip disabilities 73, including FAI 72.   2.6 Secondary Outcome Measures 2.6.1 Objective physical function Objective function was assessed using the Timed Stair Climb test, which is the time (in seconds) taken to ascend 12 stairs. Participants were instructed to ascend the stairs as quickly as possible while contacting every stair on the way up. The study administrator started the stopwatch as the participant initiated their first movement and stoped the timer once both feet contact the top step. This test is commonly used as an objective test to quantify physical function in people with hip pathology 74. Reliability coefficients of 0.90 (95% CI: 0.79, 0.96) for the stair climb were reported in a previous study evaluating performance outcomes following THA 75.  38  2.6.2 Hip pain Overall average hip pain in the past week was self-assessed by an 11 point numerical rating scale (NRS) (terminal descriptors of 0 = “no pain”, and 10 = “worst pain possible”). Such measurement has demonstrated reliability in lower limb orthopaedic impairments 76.  2.6.3 Dynamic balance The Star Excursion Balance Test (SEBT) was used to assess participants’ dynamic balance. It requires the participant to stand at the centre of the grid with eight lines extending from the centre and to reach as far as possible with the opposite leg (Figure 5). Participants reached in each direction three times and were given rest between each reach. This was repeated for the opposite leg. The maximum distance reached from the centre in each direction was recorded. If the participant lost their balance or they placed too much weight on the reaching leg (anything more than a light toe tap), the reach was deemed invalid by the assessor (study coordinator), and participants were asked to retry the attempt. It is a valid measure in assessing dynamic balance in people with a variety of lower extremity injury conditions 77.The reliability has not been reported in those with hip dysfunction, however in healthy recreational athletes, the SEBT has been shown to be reliable in all movement directions with ICC values that ranged from 0.84 to 0.92 78. 39   Figure 5. Image of Star Excursion Balance Test. The participant stands in the center of the star with one leg (right) and reaches as far as possible while maintaining balance with the opposite leg (left). Directions of reach pertain to anterolateral (A), lateral (B) and posterolateral (C).  2.6.4 Hip range of motion  Maximum active hip range of motion was assessed using a handheld goniometer for the following hip muscle groups: flexors, abductors, adductors, extensors and internal/external rotators. Flexion, abduction and adduction were measured with the participants in supine and a belt fixed around their anterior superior iliac crests. Extension was measured in prone with the belt fixed around their posterior superior iliac crests. Internal and external rotations were measured in a high seated position with the participants’ hips and knees at 90 degrees. The assessor (study coordinator) had the participants’ repeat each movement a total of two times and the largest ROM displayed on the goniometer was recorded.  C B A 40  2.7 Other Outcomes  Participant adherence was tracked in the home exercise diary: check marks were made each day they completed the exercises throughout the ten weeks. Participants were told to complete three sets of the exercises four times per week for a total of 40 sessions. Exercise session attendance was tracked by the kinesiologist and recorded during each training session. The kinesiologist required each participant to come in to UBC for exercise sessions a total of five times. The adherence and exercise attendance data can be found in Table 3. In the same exercise diary (Appendix E), the participants made note of any adverse effects, reported any new treatments and any medication they took for hip pain during the 10-week period. This data was transferred from each participant’s exercise diary to an excel spreadsheet, totaled and averaged across the group.  Global rating of change was reported by the participants during their follow-up visit. On a 15-point scale, that ranged from -7 (a very great deal worse) to +7 (a very great deal better) participants checked off how their hip pain compared to baseline. Scores were then grouped in clusters of five  to produce three distinct scores (for example: scores -3 or less scored as worse, -2 to +2 were scored as no change, +3 or greater scored as better).  41  2.8 Data Synthesis/Analysis 2.8.1 Sample size Sample size was calculated based on previous results in the literature. To our knowledge, no previous studies have published on strengthening interventions for FAI; therefore, a similar resistance training intervention in hip osteoarthritis (a related pathology) was used to calculate sample size. Steinhilber et al calculated and reported an effect size of 1.01 for an 8 week hip muscle strengthening intervention 79. Based on an alpha of 0.05, power of 0.8, and d = 1.01, a sample size of 17 participants was needed to detect differences in our primary outcomes. In order to account for attrition, the sample size was increased by 15% to give a total of 20 participants. Sample size was calculated from reference table C.2 (sample size calculation table for paired t-tests) out of the Portney & Watkins textbook 80.  2.8.2 Data management  All participant data was dissociated from identifying features such as name and address using codes. Signed consent forms and identifying information was stored separately from all other data. All computer data files were stored on a password protected computer profile, and only the study administrator and supervisor have access to the data.  42  2.8.3 Statistical analysis  To investigate the effect the strengthening intervention had on the primary and secondary outcomes, within-subjects paired t-tests were used. Baseline and follow-up primary outcomes included hip muscle strength, pain and physical function. Differences were considered significant if p < 0.05. Statistical analyses were performed using the Statistical Package for the Social Sciences (SPSS v. 20; IBM Corp., Armonk, NY).    43  Chapter 3: Results 3.1 Participant Demographics  Between May 2013 and May 2014, 46 individuals underwent clinical and radiographic screening for the study and reasons for exclusion are displayed in Figure 6. Eleven individuals were excluded due to various reasons including: evidence of OA (n=4), recent cortisone injection (n=2), not undergoing surgery (n=2), not enough hip pain (n=1), negative to imaging (n=1) and had previous hip surgery (n=1). Thirty-five remaining individuals were then screened by the study coordinator. A total of 15 of those were excluded for the following reasons: unable to attend UBC exercise sessions (n=7), not interested in the intervention (n=5), comorbidities (n=2) and not enough time before surgery (n=1). Twenty of these individuals (18 males; age = 29.8 ± 6.8 years; body mass index = 24.1 ± 2.9 kg/m2) underwent baseline testing. One individual became unable to attend any exercise sessions after week 5 due to an acute neck injury during a car accident, unrelated to the intervention. Therefore, 19 participants were included in follow-up analyses. All participants reported painful hips. Seven participants demonstrated bilateral FAI, and 13 participants demonstrated unilateral FAI. In the cases of bilateral FAI, the worse hip was considered the affected (study) hip. All 20 participants displayed an alpha angle ≥ 55 degrees (representative of cam FAI) with a group mean of 68 degrees. Three participants also displayed a lateral center edge angle > 39 degrees (representative of pincer FAI) with a group mean of 35 degrees. Therefore, 17 participants displayed cam morphology alone and three displayed mixed (cam & pincer) 44  morphology. On average, participants experienced an estimated onset of symptoms for 54 months prior to baseline assessment. The reported onset of symptoms ranged from 12 months to 132 months.     Figure 6. Participant flowchart. A flowchart of participant inclusion and retention throughout the study.  45  Table 1. Demographic information Participant ID Sex Age (years) Height (cm) Mass (kg) BMI (kg/m2) Duration of symptoms (months) FAIEXE01 M M 36.7 184.0 78.9 23.3 120 FAIEXE02 M 39.6 165.0 77.7 28.5 84 FAIEXE03 M 21.2 179.0 69.2 21.6 12 FAIEXE04 M 23.9 179.0 78.9 24.6 36 FAIEXE05 M 27.8 197.0 125.2 32.3 21 FAIEXE06 M 35.7 190.5 93.9 25.9 29 FAIEXE07 M 32.0 185.2 84.5 24.6 15 FAIEXE08 F 29.1 159.5 48.5 19.1 72 FAIEXE09 F 23.8 169.0 60.2 21.1 60 FAIEXE10 M 46.8 176.0 74.5 24.1 24 FAIEXE11 M 37.0 182.0 72.0 21.7 24 FAIEXE12 M 28.0 180.3 82.6 25.4 132 FAIEXE13 M 22.0 183.5 73.8 21.9 48 FAIEXE14 M 20.7 182.0 74.4 22.5 36 FAIEXE15 M 24.7 183.1 75.0 22.4 26 FAIEXE16 M 26.6 171.5 79.4 27.0 48 FAIEXE17 M 29.8 174.0 75.5 24.9 18 FAIEXE18 M 25.8 171.0 66.5 22.7 27 FAIEXE19 M 32.5 176.5 72.8 23.4 120 FAIEXE20 M 32.4 173.0 74.3 24.8 120        Mean for group  29.81 178.06 76.88 24.09 53.60 SD for group   6.82 8.68 14.61 2.91 40.22 Abbreviations: BMI (Body mass index), SD (standard deviation).   3.2 Outcome Data  Mean values for primary outcomes at baseline and follow-up are displayed in Table 2. Results do not include data from the person lost to follow-up and therefore not included in the analysis or mean values below (unless otherwise stated). Maximum isometric hip muscle strength values assessed using hand-held dynamometry are summarized in Table 2. Strength scores were converted to torque by 46  multiplying by the lever arm distance, then normalizing to body mass (Nm/kg) for each participant. Isometric hip muscle strength for abduction (p=0.01), adduction (p=0.02) and internal rotation (p=0.01) significantly increased at follow-up. Isometric hip muscle strength for flexion, extension and external rotation did not show statistical significance (p>0.05). Participants’ individual strength values at baseline and follow-up can be found in Appendix D.1-6. HOOS scores are summarized in Table 2. All five HOOS subscale scores significantly increased at follow-up; HOOS pain (p<0.01), HOOS symptoms (p=0.02), HOOS ADL (p<0.01), HOOS Sports (p<0.01), HOOS QoL (p=0.03). Participants’ individual HOOS scores at baseline and follow-up can be found in Appendix D.7.  Table 2 also displays the mean values of the secondary outcomes at baseline and follow-up. The NRS pain scores significantly decreased at follow-up (p<0.001). The amount of time it took participants to perform the Timed Stair Climb significantly decreased at follow-up (p<0.001). The total reach distance on the SEBT significantly increased at follow-up during affected and unaffected leg stance (p<0.001). Range of motion for hip flexion, adduction, extension, external rotation and internal rotation did not change, as significance was not reached for most directions. However, range of motion for hip abduction did significantly decrease at follow-up (p=0.01).  Finally, global ratings of change scores were reported by all participants during their follow-up assessment. Participants were asked to rate their change in overall pain in their hip from the time they began the intervention until their follow-up visit. Ten 47  participants reported their hip pain as improved, eight participants had no change and one participant got worse. Table 2. Outcome measures Primary outcomes  Baseline  (Week 0)  Mean (SD)  j (Meanna Follow-up  (Week 11) Mean (SD)  Mean difference (95% CI) Pvalue Flexion strength (Nm/kg) 1.89 (0.45) 2.04 (0.43) 0.15 (-0.03,0.34)    0.10 Abduction strength (Nm/kg) 1.53 (0.35) 1.67 (0.34) 0.14 (0.05,0.24)   0.01 Adduction strength (Nm/kg) 1.40 (0.38) 1.53 (0.39) 0.13 (0.02,0.24) 0.02 Extension strength (Nm/kg) 1.81 (0.46) 1.93 (0.50) 0.11 (-0.1,0.33) 0.29 Internal rotation strength (Nm/kg) 0.76 (0.36) 0.89 (0.36) 0.13 (0.04,0.22)    0.01 External rotation strength (Nm/kg) 0.75 (0.23) 0.77 (0.18) 0.03 (-0.05,0.10)   0.49      HOOS pain subscale (0-100)* 64.1 (12.3) 72.5 (12.3) 8.5 (3.3,13.6) <0.01 HOOS symptoms subscale (0-100)* 56.1 (13.2) 63.9 (14.6) 7.9 (1.3,14.5) 0.02 HOOS ADL subscale (0-100)* 73.0 (14.4) 83.4 (11.0) 10.4 (4.1,16.7) <0.01 HOOS sports subscale (0-100)* 51.7 (12.2) 63.4 (14.0) 11.7 (4.7,18.6) <0.01 HOOS QoL subscale (0-100)* 35.3 (17.2) 42.8 (22.0) 7.6 (1.1,14.1)    0.03 Secondary outcomes     NRS pain (0-10) 4.95 (1.47) 2.74 (1.24) -2.2 (-3.2,-1.3)    <0.001      Timed Stair Climb (seconds) 2.96 (0.66) 2.61 (0.46) -0.36 (-0.49,-0.22 <0.001 SEBT total affected stance (cm) 629 (76) 691 (74) 62 (39,85) <0.001 SEBT total left unaffected stance (cm) 643 (84) 690 (74) 47 (30,65) <0.001      Flexion ROM (º) 106.6 (10.5) 107.8 (7.1) 1.2 (-2.0,4.4) 0.44 Abduction ROM (º) A 40.8 (7.3) 36.8 (7.2) -3.9 (-6.8,-1.1)    0.01 Adduction ROM (º) 28.6 (6.4) 30.2 (8.0) 1.5 (-0.7,3.7) 0.16 Extension ROM (º) 23.5 (7.4) 26.0 (7.5) 2.5 (-1.2,6.1)    0.17 Internal rotation ROM (º) 27.0 (9.9) 28.9 (10.9) 1.9 (-1.1,4.9) 0.20 External rotation ROM (º) 35.7 (10.4) 35.2 (8.0) -0.6 (-3.8,2.7) 0.71 Abbreviations: Nm/kg (Newton meters per kilogram of body mass), NRS (numerical rating scale), HOOS (Hip disability Osteoarthritis Outcome Score), ADL (activities of daily living), QoL (quality of life), SEBT (star excursion balance test), cm (centimetre). *Higher HOOS scores represent less impairment.  Exercise diary information is summarized in Table 3. Attendance at the UBC exercise sessions was high (90 of 100 sessions attended; 90%). Participants’ 48  adherence to the home exercises was acceptable (601 of 760 sessions completed; 79%). They completed, on average, 32 of 40 home exercise sessions over the ten weeks. Eight participants reported an adverse effect during the 10-week strengthening intervention using open-ended questions asked each week.  Six of those participants had normal soreness during the first couple weeks, generally consistent with starting a new strengthening program. One of those six individuals also had low back stiffness that lasted one week. Lastly, two participants experienced lateral knee pain that lasted for 2 weeks. All participants had no substantial changes in typical medication usage. Five participants reported that they had started a new treatment or exercise regimen during the 10-week intervention. Of these five, one participant began swimming three days per week during the final three weeks of the intervention. One participant began cycling weekly at week 5. One participant had gone for two massage treatments halfway through the intervention. One participant had started an upper body resistance training program during the final 5 weeks of the intervention. Finally, one participant reported one session of hip mobilization from a physiotherapist during week 2 of the intervention.        49  Table 3. Adherence and diary information Participant ID Number of  supervised exercise sessions  Number of home sessions Adverse event? Change to meds? New treatments FAIEXE01 5 40 Yes No No FAIEXE02 5 35 No No Yes FAIEXE03 5 35 Yes No No FAIEXE04 3 N/A No No No FAIEXE05 5 27 No No No FAIEXE06 5 39 Yes No Yes FAIEXE07 5 34 Yes No No FAIEXE08 5 35 Yes No Yes FAIEXE09 5 34 Yes No No FAIEXE10 5 26 No No No FAIEXE11 4 20 Yes No Yes FAIEXE12 4 18 Yes No No FAIEXE13 5 21 No No No FAIEXE14 5 38 No No No FAIEXE15 4 32 No No Yes FAIEXE16 5 31 No No No FAIEXE17 4 25 No No No FAIEXE18 5 40 No No No FAIEXE19 4 37 No No No FAIEXE20 5 34 No No No       Mean for group 4.7 31.6    Total count    8 0 5 Note: the mean number of exercise sessions for the group does not include FAIEXE04 (lost to follow-up).    As participants progressed through the 10-week strengthening program, the length of time they spent in each phase was tracked and recorded. Table 4 displays the number of weeks each participant spent in each of the three phases. On average, the group spent 3.3 weeks in phases one and two, and 3.5 weeks in phase three.   50  Table 4. Duration of time in each exercise phase Participant ID Number of weeks  Phase 1 Phase 2 Phase 3 FAIEXE01 4.0 3.0 3.6 FAIEXE02 2.6 3.9 3.1 FAIEXE03 3.4 4.0 3.0 FAIEXE04 4.4 N/A  N/A FAIEXE05 2.7 3.9 3.1 FAIEXE06 2.9 3.1 5.4 FAIEXE07 4.1 4.0 2.0 FAIEXE08 2.7 2.0 5.0 FAIEXE09 3.0 2.1 4.7 FAIEXE10 3.0 4.3 2.6 FAIEXE11 3.9 2.0 4.1 FAIEXE12 2.7 2.0 0.0 FAIEXE13 5.3 2.0 3.7 FAIEXE14 3.1 2.7 4 FAIEXE15 3.6 3.0 4.9 FAIEXE16 2.7 4.4 3.7 FAIEXE17 2.6 2.0 6.1 FAIEXE18 3.0 3.9 3 FAIEXE19 3.0 8.0 0 FAIEXE20 3.1 2.9 4.1     Mean for group 3.3 3.3 3.5 SD for group  0.7 1.4 1.6     51  Chapter 4: Discussion The primary objective of this study was to examine the effects of a pre-surgical hip muscle strengthening intervention on hip strength, pain and function in those with FAI. Using handheld dynamometry, we found significant improvements in hip muscle strength during hip abduction, adduction and internal rotation post-intervention. Conversely, no significant differences in muscle strength were found in hip flexion, extension or external rotation post-intervention. Consistent with our hypotheses on pain and function, we found significant improvements in all five HOOS subscales post-intervention.  4.1 Interpretation of the Findings  Many studies have assessed and reported the effects of a strengthening intervention on various lower limb impairments; with studies on FAI being an exception. This study was designed to investigate the clinical and biomechanical effects of a hip strengthening intervention on those with FAI to fill that gap in the literature.  It was expected that participants that completed the 10-week hip muscle strengthening program would increase their muscle strength, since the intervention itself was comprised mainly of muscle strengthening exercises. These exercises were prescribed with the ACSM resistance training guidelines in mind to promote meaningful strength increases. However, not all six movements of the hip significantly increased in hip muscle strength post-intervention. In line with expectations, hip abduction strength significantly increased, as many of the exercises in each phase were devoted to 52  targeting the hip abductors. Specifically, clamshells were performed in phase one and with a weight cuff in phase two, 4-point kneeling hip abduction and side-steps with a resistance band in phases two and three, and standing hip abduction with a weight cuff in phase three. Conversely, flexion and extension are movements of the hip that encompass muscles often stronger at baseline. One of the reasons this study did not see significant strength improvements in these two movements could be because the exercises did not provide enough challenge for the hip flexors and extensors. With a goal of ensuring pain-free activation of muscle around the hip joint, it is possible that the exercise intensity may have been lowered, thus resulting in less challenging exercise and smaller gains. Hip flexion and extension are actions that are performed on a consistent basis in movements such as walking or going up stairs; thus these movements are used often, resulting in higher levels of baseline strength. Achieving a balance between prescribing exercises that are challenging enough, targeting the proper muscles and not eliciting hip pain can be difficult. Even though each participant had FAI, their amount of restriction and pain free range of movement could vary. Small exercise adaptations were made to account for these individual variations in pain and restriction. Strengthening the muscles that surround the hip joint helps to support the hip and make the hip joint more stable 61. In particular, increasing the strength of these muscles may improve abnormal repetitive stresses during walking commonly seen in those with weak hip muscles 81. The significant increase in muscle strength in certain hip motions may also help account for the improvement in pain and function seen in participants after the 10-week strengthening program. The strengthened abductor, 53  adductor and internal rotator muscles can help align the femur in the acetabulum, creating a more stable hip joint. It has been shown that weak hip muscles lead to reduced hip motion and instability within the hip joint, which can cause hip pain 61, suggesting that stronger hip muscles can help counteract that effect. After the strengthening intervention, participants’ mean hip flexion strength increased by 8%, abduction increased by 9%, adduction increased by 9%, extension increased by 6%, internal rotation increased by 17% and external rotation increased by 4%. Thorborg et al., reported that increases in strength using hand-held dynamometry above 10% can be considered “real” changes 82, as applied to healthy individuals. The 17% improvement in internal rotation strength clearly surpasses this cutoff. It is possible, however, that a meaningful cutoff for strength increases would be lower in clinical populations, because clinical populations, such as those with FAI, have lower baseline strength values than healthy individuals, and thus may benefit from smaller improvements. The strength increases seen for flexion, abduction and adduction of the hip may be clinically meaningful or may near meaningful levels of improvements.  Currently, there is no published literature on the effectiveness of a pre-habilitation program on post-surgical outcomes in people with FAI. However, research supports the idea that higher functioning individuals before surgery continue to be higher functioning after surgery. For example, men and women with greater musculoskeletal strength compared to men and women with low musculoskeletal strength had 5% and 9% fewer functional problems respectively, years after total hip and knee replacement surgery 62. Recovery from surgery can be a long and trying process; however, participants who have done a pre-habilitation program better understand proper muscle activation and 54  exercise execution. This familiarity and recent exposure to training can help the muscles of their affected joint recover faster. Thus, this program could be used to help those with FAI better recover from surgery, but future research is needed. It is evident that exercise can improve pain and function across various lower-limb impaired populations 63-65,83-85. The exercises included in this study were designed to be functional in nature, specifically to improve movements that people with FAI perform often during ADLs. Many of the exercises promoted the participants to engage their core and challenge their balance while strengthening their hip muscles. Targeting the core muscles and emphasizing both static and dynamic balance during movement could be why the HOOS subscale scores significantly improved. In addition, even though a reduction in pain was reported after the intervention, it is unknown whether reductions in pain were solely due to the strengthening program. However, the absence of pain medication taken and lack of other treatments commenced during the ten weeks suggest little external influence. In order to determine if these improvements on the HOOS were clinically meaningful, we compared our HOOS scores to another study that reported minimal important change (MIC) for HOOS scores following hip surgery 86. The MIC can be defined as the smallest change in score which is perceived as important by patients, clinicians, or relevant others. In the Kemp et al. study, the MIC for HOOS pain, ADL, and sport were 9, 6, and 10, respectively. The mean differences in the current study were 9, 10, and 12, indicating meaningful changes in pain, ADL, and sport scores at follow-up. HOOS pain, symptoms and ADL subscale scores each increased by 14%, 55  and sport and QoL subscale scores each increased by 23% after the 10-week strengthening program.  Participants’ self-reported pain was also assessed using an 11-point NRS. The mean baseline score for participants in this FAI cohort was 4.9 at baseline and 2.7 at follow-up, with a mean difference of 2.2. According to an article assessing the responsiveness on the NRS on pain, the difference between baseline and follow-up scores must exceed 2.1 in order to display a minimally clinically important difference 87. Therefore, participants in our study showed a clinical and statistical improvement in NRS pain scores, consistent with the improvements displayed in HOOS pain scores. The SEBT is an outcome measure in which the stance leg requires strength, proprioception, neuromuscular control and adequate range of motion at the hip joint 88. For the purpose of this study, the SEBT scores for each of the eight directions were summed to reduce the number of variables. This provided one value for the SEBT score for stance on the affected limb (most symptomatic hip) and one for the stance on the unaffected limb (least symptomatic/healthy hip). In an article reporting on SEBT reliability in healthy adults, the smallest detectable differences (SDD) were reported as a percentage for each of the eight directions. The SDD is the smallest difference between a baseline and follow-up measure that can be considered a “real” change, meaning the difference in scores is greater than the measurement error of the test 89. Munro & Herrington reported a SDD of 5-7% for all directions, therefore, a true change in SEBT performance would have to improve by 7% or greater between tests 78. Participants in the current study improved their total score by 9% on their affected limb and 7% on their unaffected limb. While the aggregate score is different from individual 56  values reported elsewhere, this does suggest that the participants’ SEBT scores at follow-up can be considered real improvement. Participants’ hip ROM did not change from baseline to follow-up, with the exception of a decrease in hip abduction. One of the reasons ROM did not change could be because ROM was not a focus in the strengthening program. The intervention did not include flexibility exercises to target increasing maximal ROM. Participants were encouraged to maintain their normal routine with the exception of the strengthening intervention, with no new stretching or ROM exercises introduced. Abduction ROM could have decreased because maximal ROM was measured, and exercises during the ten weeks were not performed in the participants’ terminal range of movement. The muscle was strengthened in the pain-free ROM of each participant and for most participants this was less than maximal ROM.  4.2 Study Limitations Despite the encouraging results found in this study, there are a number of limitations. First, the absence of a control group is considered a limitation in the study. However, since this was a within-subject design, participants served as their own controls, as pre-post intervention measures of the same participant were compared. Though appropriately powered for our primary objectives, the exploratory nature of this study was limited by a small sample size. However, these initial findings do support the impetus for future studies with larger sample sizes. A randomized control trial (RCT) with an exercise group and a control group would be ideal for controlling variables 57  including trainer contact hours. However this was not possible at this time for a number a reasons. Larger studies are costly, require long time commitments, and require previous pilot data or other literature for justification. No previous work has examined the effect of muscle strengthening in those with FAI. Further, the expense and time constraints limited a more complex study design.    A hand-held dynamometer was used for strength assessment of hip muscles. Intra-rater reliability of hand-held dynamometry has been shown to be lower compared to the gold standard of isokinetic dynamometry 90, due to the influence of the investigator’s strength when resisting the measured forces. Nevertheless, hand-held dynamometry assessments are more clinically feasible than isokinetic dynamometry, and show good-to-excellent reliability for the hip movements that were tested in this study 90. Finally, both males and females were recruited in our study to aid in the generalizability of the findings, as both genders experience FAI. However, since only two females were recruited, the majority of our data came from male participants. It is unclear whether our findings would have changed if our cohort was comprised of a greater number of females, and generalization of our findings to females with FAI should be made with caution.   4.3 Clinical Implications and Future Directions This is the first study to assess the effect and efficacy of a muscle strengthening program in adults with FAI. The results from this study suggest clinically meaningful changes in strength, pain, and function after a 10-week muscle strengthening 58  intervention. Our findings show that an appropriately designed muscle strengthening intervention comprised of resistance training, balance and functional exercises can be a safe and effective approach to improving muscle strength in young adults with FAI. This improvement in strength is accompanied by improvements in self-reported pain and function. These findings support similar results in other studies that included a preoperative strengthening intervention for people with other lower limb pathologies 63-65.  Furthermore, participant attendance during supervised exercise sessions was excellent at 90%, and they completed, on average, 79% of home exercises (3.2 exercises per week). This is much higher than the average reported adherence rate of 66% for exercise interventions in the literature 91. A reason for this could be because of the scheduling flexibility of the study coordinator/kinesiologist. Most participants worked or went to school during the day and were only available for supervised training sessions in the evenings. Participants were encouraged to choose a time that was convenient for them for training, in order to encourage adherence. In addition, five supervised sessions over the ten weeks ensured the participants did not go more than two to three weeks without trainer contact. Overall, attrition was low with only one participant lost to follow-up, thus retaining 95% of participants throughout the study. Attrition rates for exercise interventions in the literature are quite variable and tend to have a greater amount of participant dropout as the duration of the intervention increases 91. Though this initial feasibility study shows promising findings, it is clear that more research is needed to draw stronger conclusions. This study provides a rationale for 59  conducting a more resource-intensive clinical trial to investigate the effects of a strengthening intervention in a larger sample with a control group comparison. Even though our study showed improvements in many of the outcome measures, there are some areas of the study that could be improved. Although participants were asked to include any adverse events at other lower limb and back joints, analysis of muscle strength at these other joints was not undertaken. As a result, some of the exercises may have also strengthened the muscles around their knees and ankles, and contributed to their overall improvement in function. It remains unclear whether the prescribed exercises increased the strength of other lower limb muscle groups and not just the ones around the hip.  Future studies in this area should recruit a larger number of study participants with a more even gender ratio. Also, incorporating more challenging exercises for the hip flexors and extensors should be included. Future research should also include a longer exercise intervention, for example 12-16 weeks in duration. It is possible that participants would have greater muscle strength improvements with more time to strengthen their hip muscles. Finally, similar to the current study, having a blinded assessor during baseline and follow-up assessments would be essential to eliminate any possible tester bias for all outcome measures. In conclusion, we found that a 10-week hip muscle strengthening program could be safely completed by adults with FAI and that statistically significant changes in clinical and biomechanical outcomes were achieved. Findings of this study can improve our understanding of FAI and our treatment of the condition, and may be useful for clinicians involved in treating those with FAI. Though these results are based on an 60  exploratory study, if future controlled studies with larger sample sizes can show similar findings, it would have important clinical and biomechanical implications, as well as an important impact on the management of symptoms for individuals with FAI. 61  References 1. Ganz R, Parvizi J, Beck M, Leunig M, Notzli H, Siebenrock KA. Femoroacetabular impingement: a cause for osteoarthritis of the hip. Clin Orthop Relat Res 2003:112-20. 2. Leunig M, Beaule PE, Ganz R. The concept of femoroacetabular impingement: current status and future perspectives. Clin Orthop Relat Res 2009;467:616-22. 3. Agricola R, Heijboer MP, Bierma-Zeinstra SM, Verhaar JA, Weinans H, Waarsing JH. Cam impingement causes osteoarthritis of the hip: a nationwide prospective cohort study (CHECK). Ann Rheum Dis 2013;72:918-23. 4. Audenaert E, Van Houcke J, Maes B, Vanden Bossche L, Victor J, Pattyn C. Range of motion in femoroacetabular impingement. Acta Orthop Belg 2012;78:327-32. 5. Casartelli NC, Maffiuletti NA, Item-Glatthorn JF, et al. Hip muscle weakness in patients with symptomatic femoroacetabular impingement. Osteoarthritis Cartilage 2011;19:816-21. 6. Guenther JR, Gilbart MK, Hunt MA. People with femoroacetabular impingement exhibit altered frontal and transverse plane strength, movement, and gait characteristics compared to those without impingement. In: Osteoarthritis Research Society International World Congress; 2012; Barcelona, Spain; 2012. 7. Kennedy MJ, Lamontagne M, Beaule PE. Femoracetabular impingement alters hip and pelvic biomechanics during gait. Gait Posture 2009;30:41-4. 8. Hunt MA, Gunether JR, Gilbart MK. Kinematic and kinetic differences during walking in patients with and without symptomatic femoroacetabular impingement. Clin Biomech 2013;28:519-23. 9. Siebenrock KA, Ferner F, Noble PC, Santore RF, Werlen S, Mamisch TC. The cam-type deformity of the proximal femur arises in childhood in response to vigorous sporting activity. Clin Orthop Relat Res 2011;469:3229-40. 10. Pollard TC, Villar RN, Norton MR, et al. Genetic influences in the aetiology of femoroacetabular impingement: a sibling study. J Bone Joint Surg Br 2010;92:209-16. 11. Agricola R, Heijboer MP, Ginai AZ, et al. A cam deformity is gradually acquired during skeletal maturation in adolescent and young male soccer players: a prospective study with minimum 2-year follow-up. Am J Sports Med 2014;42:798-806. 62  12. Myers SR, Eijer H, Ganz R. Anterior femoroacetabular impingement after periacetabular osteotomy. Clin Orthop Relat Res 1999:93-9. 13. Leunig M, Huff TW, Ganz R. Femoroacetabular impingement: treatment of the acetabular side. Instr Course Lect 2009;58:223-9. 14. Lavigne M, Parvizi J, Beck M, Siebenrock KA, Ganz R, Leunig M. Anterior femoroacetabular impingement: part I. Techniques of joint preserving surgery. Clin Orthop Relat Res 2004:61-6. 15. Agricola R, Waarsing JH, Arden NK, et al. Cam impingement of the hip-a risk factor for hip osteoarthritis. Nat Rev Rheumatol 2013;10:630-4. 16. Leunig M, Casillas MM, Hamlet M, et al. Slipped capital femoral epiphysis: early mechanical damage to the acetabular cartilage by a prominent femoral metaphysis. Acta Orthop Scand 2000;71:370-5. 17. Eijer H, Podeszwa DA, Ganz R, Leunig M. Evaluation and treatment of young adults with femoro-acetabular impingement secondary to Perthes' disease. Hip Int 2006;16:273-80. 18. Eijer H, Myers SR, Ganz R. Anterior femoroacetabular impingement after femoral neck fractures. J Orthop Trauma 2001;15:475-81. 19. Murray RO. The aetiology of primary osteoarthritis of the hip. Br J Radiol 1965;38:810-24. 20. Stulberg SD HW. Acetabular dysplasis and development of osteoarthritis of hip. In: Hip Society; 1974; St. Louis: C.V. Mosby; 1974. p. 82-93. 21. Byrd JW. Labral lesions: an elusive source of hip pain case reports and literature review. Arthroscopy 1996;12:603-12. 22. Fitzgerald RH, Jr. Acetabular labrum tears. Diagnosis and treatment. Clin Orthop Relat Res 1995:60-8. 23. Monazzam S, Bomar JD, Dwek JR, Hosalkar HS, Pennock AT. Development and prevalence of femoroacetabular impingement-associated morphology in a paediatric and adolescent population: A CT study of 225 patients. Bone Joint J 2013;95-B:598-604. 24. Hack K, Di Primio G, Rakhra K, Beaule PE. Prevalence of cam-type femoroacetabular impingement morphology in asymptomatic volunteers. J Bone Joint Surg Am 2010;92:2436-44. 25. Clohisy JC, Baca G, Beaule PE, et al. Descriptive epidemiology of femoroacetabular impingement: a North American cohort of patients undergoing surgery. Am J Sports Med 2013;41:1348-56. 63  26. Nogier A, Bonin N, May O, et al. Descriptive epidemiology of mechanical hip pathology in adults under 50 years of age. Prospective series of 292 cases: Clinical and radiological aspects and physiopathological review. Orthop Traumatol Surg Res 2010;96:S53-S8. 27. Clohisy JC, Knaus ER, Hunt DM, Lesher JM, Harris-Hayes M, Prather H. Clinical presentation of patients with symptomatic anterior hip impingement. Clin Orthop Relat Res 2009;467:638-44. 28. Kubiak-Langer M, Tannast M, Murphy SB, Siebenrock KA, Langlotz F. Range of motion in anterior femoroacetabular impingement. Clin Orthop Relat Res 2007;458:117-24. 29. Banerjee P, McLean CR. Femoroacetabular impingement: a review of diagnosis and management. Curr Rev Musculoskelet Med 2011;4:23-32. 30. Beck M, Kalhor M, Leunig M, Ganz R. Hip morphology influences the pattern of damage to the acetabular cartilage: femoroacetabular impingement as a cause of early osteoarthritis of the hip. J Bone Joint Surg Br 2005;87:1012-8. 31. Byrd JW. Femoroacetabular Impingement in Athletes: Current Concepts. Am J Sports Med 2013. 32. Kassarjian A, Yoon LS, Belzile E, Connolly SA, Millis MB, Palmer WE. Triad of MR arthrographic findings in patients with cam-type femoroacetabular impingement. Radiology 2005;236:588-92. 33. Dolan MM, Heyworth BE, Bedi A, Duke G, Kelly BT. CT reveals a high incidence of osseous abnormalities in hips with labral tears. Clin Orthop Relat Res 2011;469:831-8. 34. Wenger DE, Kendell KR, Miner MR, Trousdale RT. Acetabular labral tears rarely occur in the absence of bony abnormalities. Clin Orthop Relat Res 2004:145-50. 35. Zebala LP, Schoenecker PL, Clohisy JC. Anterior femoroacetabular impingement: a diverse disease with evolving treatment options. Iowa Orthop J 2007;27:71-81. 36. Ito K, Minka MA, Leunig M, Werlen S, Ganz R. Femoroacetabular impingement and the cam-effect. A MRI-based quantitative anatomical study of the femoral head-neck offset. J Bone Joint Surg Br 2001;83:171-6. 37. Ganz R, Leunig M, Leunig-Ganz K, Harris WH. The etiology of osteoarthritis of the hip: an integrated mechanical concept. Clin Orthop Relat Res 2008;466:264-72. 64  38. Notzli HP, Wyss TF, Stoecklin CH, Schmid MR, Treiber K, Hodler J. The contour of the femoral head-neck junction as a predictor for the risk of anterior impingement. J Bone Joint Surg Br 2002;84:556-60. 39. Pflirrmann CW MB, Dora C, Kalberer F, Zanetti M, Hodler J. Cam and pincer femoroacetabular impingement: characteristic MR arthrographic findings in 50 patients. Radiology 2006;240:778-85. 40. Siebenrock KA, Kalbermatten DF, Ganz R. Effect of pelvic tilt on acetabular retroversion: a study of pelves from cadavers. Clin Orthop Relat Res 2003:241-8. 41. Agricola R, Heijboer MP, Roze RH, et al. Pincer deformity does not lead to osteoarthritis of the hip whereas acetabular dysplasia does: acetabular coverage and development of osteoarthritis in a nationwide prospective cohort study (CHECK). Osteoarthritis Cartilage 2013;21:1514-21. 42. Kaplan KM, Shah MR, Youm T. Femoroacetabular impingement--diagnosis and treatment. Bull NYU Hosp Jt Dis 2010;68:70-5. 43. Philippon MJ, Maxwell RB, Johnston TL, Schenker M, Briggs KK. Clinical presentation of femoroacetabular impingement. Knee Surg Sports Traumatol Arthrosc 2007;15:1041-7. 44. Philippon MJ, Schenker ML. Arthroscopy for the treatment of femoroacetabular impingement in the athlete. Clin Sports Med 2006;25:299-308, ix. 45. Laude F, Boyer T, Nogier A. Anterior femoroacetabular impingement. Joint Bone Spine 2007;74:127-32. 46. Ito K, Leunig M, Ganz R. Histopathologic features of the acetabular labrum in femoroacetabular impingement. Clin Orthop Relat Res 2004:262-71. 47. Vad VB, Bhat AL, Basrai D, Gebeh A, Aspergren DD, Andrews JR. Low back pain in professional golfers: the role of associated hip and low back range-of-motion deficits. Am J Sports Med 2004;32:494-7. 48. Kennedy AA, Rosenfeld SB. Orthopedic perspectives on femoroacetabular impingement. Pediatr Radiol 2013;43 Suppl 1:S83-9. 49. Aprato A, Jayasekera N, Villar R. Timing in hip arthroscopy: does surgical timing change clinical results? Int Orthop 2012;36:2231-4. 50. Bedi A, Chen N, Robertson W, Kelly BT. The management of labral tears and femoroacetabular impingement of the hip in the young, active patient. Arthroscopy 2008;24:1135-45. 65  51. Gedouin JE, May O, Bonin N, et al. Assessment of arthroscopic management of femoroacetabular impingement. A prospective multicenter study. Orthop Traumatol Surg Res 2010;96:S59-67. 52. Malviya A, Stafford GH, Villar RN. Impact of arthroscopy of the hip for femoroacetabular impingement on quality of life at a mean follow-up of 3.2 years. J Bone Joint Surg Br 2012;94:466-70. 53. Papalia R, Del Buono A, Franceschi F, Marinozzi A, Maffulli N, Denaro V. Femoroacetabular impingement syndrome management: arthroscopy or open surgery? Int Orthop 2012;36:903-14. 54. Laude F, Sariali E, Nogier A. Femoroacetabular impingement treatment using arthroscopy and anterior approach. Clin Orthop Relat Res 2009;467:747-52. 55. Ng VY, Arora N, Best TM, Pan X, Ellis TJ. Efficacy of surgery for femoroacetabular impingement: a systematic review. Am J Sports Med 2010;38:2337-45. 56. Shearer DW, Kramer J, Bozic KJ, Feeley BT. Is hip arthroscopy cost-effective for femoroacetabular impingement? Clin Orthop Relat Res 2012;470:1079-89. 57. Emara K, Samir W, Motasem el H, Ghafar KA. Conservative treatment for mild femoroacetabular impingement. J Orthop Surg 2011;19:41-5. 58. Bedi A, Kelly BT. Femoroacetabular impingement. J Bone Joint Surg Am 2013;95:82-92. 59. Leunig M, Robertson WJ, Ganz R. Femoroacetabular impingement: Diagnosis and management, including open surgical technique. Oper Techn Sport Med 2007;15:178-88. 60. Guenther JR, Gilbart MK, Hunt MA. People with femoroacetabular impingement exhibit altered frontal and transverse plane strength, movement, and gait characteristics compared to those without impingement. Osteoarthritis Cartilage 2012;20:S103-S4. 61. Retchford TH, Crossley KM, Grimaldi A, Kemp JL, Cowan SM. Can local muscles augment stability in the hip? A narrative literature review. J Musculoskelet Neuronal Interact 2013;13:1-12. 62. Fortin PR, Clarke AE, Joseph L, et al. Outcomes of total hip and knee replacement: preoperative functional status predicts outcomes at six months after surgery. Arthritis Rheum 1999;42:1722-8. 63. Kean CO, Birmingham TB, Garland SJ, Bryant DM, Giffin JR. Preoperative strength training for patients undergoing high tibial osteotomy: A prospective cohort study with historical controls. J Orthop Sports Phys Ther 2011;41:52-9. 66  64. Rooks DS, Huang J, Bierbaum BE, et al. Effect of preoperative exercise on measures of functional status in men and women undergoing total hip and knee arthroplasty. Arthritis Rheum 2006;55:700-8. 65. Topp R, Swank AM, Quesada PM, Nyland J, Malkani A. The effect of prehabilitation exercise on strength and functioning after total knee arthroplasty. PM R 2009;1:729-35. 66. Kraemer WJ, Ratamess NA. Fundamentals of resistance training: progression and exercise prescription. Med Sci Sports Exerc 2004;36:674-88. 67. Garber CE, Blissmer B, Deschenes MR, et al. American College of Sports Medicine position stand. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: guidance for prescribing exercise. Med Sci Sports Exerc 2011;43:1334-59. 68. American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. Med Sci Sports Exerc 2009;41:687-708. 69. Thorborg K, Bandholm T, Holmich P. Hip- and knee-strength assessments using a hand-held dynamometer with external belt-fixation are inter-tester reliable. Knee Surg Sports Traumatol Arthrosc 2012. 70. Thorborg K, Petersen J, Magnusson SP, Holmich P. Clinical assessment of hip strength using a hand-held dynamometer is reliable. Scand J Med Sci Spor 2010;20:493-501. 71. Pua YH, Wrigley TV, Cowan SM, Bennell KL. Intrarater test-retest reliability of hip range of motion and hip muscle strength measurements in persons with hip osteoarthritis. Arch Phys Med Rehabil 2008;89:1146-54. 72. Hinman RS, Dobson F, Takla A, O'Donnell J, Bennell KL. Which is the most useful patient-reported outcome in femoroacetabular impingement? Test-retest reliability of six questionnaires. Br J Sports Med 2014;48:458-63. 73. Nilsdotter AK, Lohmander LS, Klassbo M, Roos EM. Hip disability and osteoarthritis outcome score (HOOS)--validity and responsiveness in total hip replacement. BMC Musculoskelet Disord 2003;4:10. 74. Bennell K, Dobson F, Hinman R. Measures of physical performance assessments: Self-Paced Walk Test (SPWT), Stair Climb Test (SCT), Six-Minute Walk Test (6MWT), Chair Stand Test (CST), Timed Up & Go (TUG), Sock Test, Lift and Carry Test (LCT), and Car Task. Arthritis Care Res 2011;63 Suppl 11:S350-70. 75. Kennedy DM, Stratford PW, Wessel J, Gollish JD, Penney D. Assessing stability and change of four performance measures: a longitudinal study evaluating 67  outcome following total hip and knee arthroplasty. BMC Musculoskelet Disord 2005;6:3. 76. Bellamy N. Osteoarthritis clinical trials: candidate variables and clinimetric properties. J Rheumatol 1997;24:768-78. 77. Kinzey SJ, Armstrong CW. The reliability of the star-excursion test in assessing dynamic balance. J Orthop Sport Phys 1998;27:356-60. 78. Munro AG, Herrington LC. Between-session reliability of the star excursion balance test. Phys Ther Sport 2010;11:128-32. 79. Steinhilber B, Haupt G, Miller R, et al. Feasibility and efficacy of an 8-week progressive home-based strengthening exercise program in patients with osteoarthritis of the hip and/or total hip joint replacement: a preliminary trial. Clin Rheumatol 2012;31:511-9. 80. Portney LG, Watkins MP. Foundations of Clinical Research: Applications to Practice. 3rd ed. Upper Saddle River, NJ: Pearson Prentice Hall; 2009. 81. Hunt MA, Guenther JR, Gilbart MK. Kinematic and kinetic differences during walking in patients with and without symptomatic femoroacetabular impingement. Clin Biomech 2013;28:519-23. 82. Thorborg K, Petersen J, Magnusson SP, Holmich P. Clinical assessment of hip strength using a hand-held dynamometer is reliable. Scand J Med Sci Sports 2010;20:493-501. 83. Bennell KL, Hinman RS. A review of the clinical evidence for exercise in osteoarthritis of the hip and knee. J Sci Med Sport 2011;14:4-9. 84. Krauss I, Steinhilber B, Haupt G, Miller R, Martus P, Janssen P. Exercise therapy in hip osteoarthritis- a randomized controlled trial. Dtsch Arztebl Int 2014;111:592-9. 85. Aguiar GC, Do Nascimento MR, De Miranda AS, Rocha NP, Teixeira AL, Scalzo PL. Effects of an exercise therapy protocol on inflammatory markers, perception of pain, and physical performance in individuals with knee osteoarthritis. Rheumatol Int 2014:Epub 2014 Oct 10. 86. Kemp JL, Collins NJ, Roos EM, Crossley KM. Psychometric properties of patient-reported outcome measures for hip arthroscopic surgery. Am J Sports Med 2013;41:2065-73. 87. Michener LA, Snyder AR, Leggin BG. Responsiveness of the numeric pain rating scale in patients with shoulder pain and the effect of surgical status. J Sport Rehabil 2011;20:115-28. 68  88. Olmsted LC, Carcia CR, Hertel J, Shultz SJ. Efficacy of the Star Excursion Balance Tests in Detecting Reach Deficits in Subjects With Chronic Ankle Instability. J Athl Train 2002;37:501-6. 89. Bruynesteyn K, Boers M, Kostense P, van der Linden S, van der Heijde D. Deciding on progression of joint damage in paired films of individual patients: smallest detectable difference or change. Ann Rheum Dis 2005;64:179-82. 90. Stark T, Walker B, Phillips JK, Fejer R, Beck R. Hand-held dynamometry correlation with the gold standard isokinetic dynamometry: a systematic review. PM R 2011;3:472-9. 91. Linke SE, Gallo LC, Norman GJ. Attrition and adherence rates of sustained vs. intermittent exercise interventions. Ann Behav Med 2011;42:197-209.     69  Appendix A: Informed Consent and Letters of Explanation  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          INFORMED CONSENT FORM Project Title: Pre-operative exercise intervention for people with femoroacetabular impingement Principal Investigator:  Dr. Michael A. Hunt PhD, PT    Co-investigator: Dr. Michael K. Gilbart MD, MEd, FRCS(C) Team Members: Jerrad Guenther BSc. (Exercise Science), MSc (cand.)  Contact information: Principal Investigator:    Co-investigator    Graduate Student: Michael A. Hunt PhD, PT    Michael K. Gilbart MD, Med, FRCS (C) Jerrad Guenther BSc., MSc (c)  Assistant Professor    Assistant Professor    Research Assistant Dept. of Physical Therapy    Department of Orthopedics  Dept. of Physical Therapy 2177 Wesbrook Mall        UBC Hospital     University of British Columbia 212, Friedman Building    2nd floor, Unit 2C – 2211 Wesbrook Mall (604) xxx-xxxx Vancouver, BC     Vancouver, BC  V6T 1Z3     V6T 2B5  (604) xxx-xxxx     (604) xxx-xxxx   BACKGROUND AND PURPOSE Impingement of the hip prevents full movements at that joint and this restriction causes pain. With prolonged pain and altered walking patterns, there is a possibility of developing muscle weakness, which may result in further hip damage. We aim to examine the changes in hip muscle strength, pain, and function following a 10-week hip muscle strengthening intervention. Exercise is a common treatment for many injuries and joint disorders. Importantly, exercise has been shown to be beneficial in reducing pain and improving function. The effects of a muscle strengthening intervention on people with hip impingement are unknown.  You are being invited to participate in this study that will assess your hip muscle strength, pain and physical function before and after a 10-week exercise intervention. Department of Physical Therapy Faculty of Medicine 212, Friedman Building 2177 Wesbrook Mall    Vancouver, British Columbia V6T 1Z3 Phone: 604.xxx.xxxx Fax:  604.xxx.xxxx Web:     www.physicaltherapy.med.ubc.ca  70   This study will help us better understand different treatment approaches for hip impingement as it relates to muscle strength and function. By identifying treatments that improve pain and joint function, we can decrease the personal burden and improve quality of life. As a result, we may be better able to manage pain and physical dysfunction in those with a hip impingement.  DETAILS OF THE STUDY Testing will be performed at Dr. Hunt’s Motion Analysis and Biofeedback Laboratory at UBC and will be comprised of measurement of physical function, muscle strength, and walking patterns. You will also complete self-report questionnaires to assess pain and physical function. After testing, you will begin a 10 week high intensity resistance training program, 4 sessions per week. You will attend 5 supervised training sessions in weeks 1,2,4,6 and 8 at the Multipurpose gymnasium, Department of Physical Therapy, with the remaining sessions being completed at home. The training sessions will consist of lower limb exercises using body mass, resistance bands, exercise balls, and ankle weights.  During the high intensity resistance training program you will be required to perform the exercises at home a total of 4 times per week. You will perform all 6 exercises to the required amount of repetitions and sets as instructed by the study kinesiologist. You must also fill out the exercise diary for each week during the 10-week program as honest and accurately as possible.  During a testing session in the lab, the following measurements will be collected:  1) Maximal hip muscle strength: We will use handheld dynamometry to measure your hip strength. A handheld dynamometer is a device that fits in the palm of one’s hand that measures the force of a body segment pushing against it. For our study, we will test the strength of your hip flexors (front of hip), extensors (back of hip), abductors (outside of hip), adductors (inside of hip), as well as the hip rotators (inside and outside of thigh). You will be asked to push as hard as you can with you leg against the dynamometer, three times (about 5 seconds each time) for each muscle group. You will be given plenty of rest between each trial to minimize the effect of fatigue.  2) Self-report questionnaires of pain and physical function: These questionnaires will be seven pages in length and will ask you questions regarding the extent of your hip pain, and the magnitude of difficulty in performing certain physical tasks. Please note that you do not need to answer any questions which you are not comfortable answering.  3) Assessment of your physical function:  71  You will be asked to climb up and down a flight of 12 stairs which will be timed with a stopwatch. This will be completed twice in succession, though you will be given a rest period between trials. You will be asked to perform 3 maximal effort single leg hops in a straight line using the same leg. This will be done for both legs and you will be given a rest between trials.  4) Assessment of balance: We will use the star excursion balance test to assess your dynamic balance while standing on one leg. You will stand at the center of the grid with 8 lines extending from the center and reach as far as possible with the opposite leg. You will reach in each direction 3 times and will be given rest between each reach.  5) Three dimensional gait analysis: You will be asked to walk barefoot and wearing shorts and a special t-shirt with 2 holes cut out. Reflective skin markers will be attached to your skin at various sites such as the ankle, knee and hip (additional markers will be placed under your chin and on your back within the holes cut into the t-shirt). We will also measure muscle activity of your hip muscles using electromyography. Electromyography is the measurement of the electrical activity in your body that causes your muscles to work. This requires the attachment of electrodes to your skin around your hip joint (similar to how an electrocardiogram measures the electrical activity of your heart). These electrodes only measure the muscle activity and do not provide any electrical stimulation to you.  You will be filmed with special cameras that track the movement of the reflective markers as you walk along a walkway. The movement of the markers enables a recreation of a moving “stick figure” on the computer screen that mimics your movements. The image in no way provides any information about your identity, and all files stored on the compute will be recognized only based on your unique coded identifier (ie. not your name). From the walking tests, we will be able to analyze the movements at your trunk, hip, knee and ankle, as well as the forces acting across each joint. You will complete approximately 5 trials of walking at your own pace for normal walking and each trial will be approximately 10m in length.  You must report to the investigator any pain or discomfort during any of the testing procedures. As noted above, you will be required to wear shorts and a t-shirt during all testing. You may either bring your own shorts or we can provide you with some.   PARTICIPATION CRITERIA: You are invited to participate if you are between the ages of 18 and 75 and have evidence of hip femoroacetabular impingement. You must also have no history of significant lower body injuries or conditions that would impair the measurement of walking or hip strength, no history of significant neurological injury that affects your walking, no evidence of arthritis in the hip, knee or ankle, no history of avascular necrosis of the hip, and no history of, or planned, lower limb 72  joint replacement surgery. You must not be planning on starting a strength training intervention for the next ten weeks. Finally, you must be able to understand written or spoken English or have the ability to have a family member present to translate.  RISKS/SIDE-EFFECTS: You may experience some discomfort in the study hip during the high intensity exercise program. If this is a constant issue you should inform the study kinesiologist. You may experience some mild skin irritation from the reflective markers. You may also experience some mild muscle discomfort during the muscle strength testing. If this is bothersome, you should inform the tester immediately. In the unlikely event of a medical emergency during the assessment, the research personnel will call 911.  BENEFITS: You will not receive any direct benefit from participation in this study. However, the findings from this study may contribute to the development of better treatment options for people with hip impingement.   REIMBURSEMENT: You will not be reimbursed for your involvement in this study. However, the costs of parking or taking transit to attend study sessions, if necessary, will be reimbursed. Receipts for parking and transit must be kept and given to the research assistant.  CONFIDENTIALITY: Your confidentiality will be respected.  However, research records and health or other source records identifying you may be inspected in the presence of the Investigator or his or her designate by representatives of Health Canada, and The University of British Columbia Clinical Research Ethics Board for the purpose of monitoring the research.  Your data will remain de-identified and no researcher not listed on this form will have access to any confidential information.  VOLUNTARY PARTICIPATION: Participation in the study is completely voluntary.  You may refuse to participate or withdraw from the study at any time with no effect on you, including clinical care. You are not obligated to provide any reason for your withdrawal, should you choose to do so.  Participation in this study does not prevent you from participating in other research studies in the future.  Further, you may ask to have your data permanently removed from our database at any time without penalty. If you are willing to be contacted in the future for other research studies, please indicate this on the consent form.  You can always withdraw this consent to be contacted in the future, should you 73  change your mind.  In this case, your name and contact information will be removed from our records.  Participation in any future research is completely voluntary and will have no bearing on the results of the current research project. Signing this consent form in no way limits your legal rights against the sponsor, investigators, or anyone else, and you do not release the study doctors or participating institutions from their legal and professional responsibilities.  FURTHER QUESTIONS? If you have any concerns about your experience or rights as a research subject, you may contact the Research Subject Information Line in the UBC Office of Research Services at 604-xxx-xxxx or if long distance e-mail to xxxx@ors.ubc.ca.  You will be given a copy of the signed and dated consent form. Please keep this information letter for future reference.   74  Appendix B: Images of the Exercises    The University of British Columbia  Motion Analysis and Biofeedback Laboratory  FAI Strengthening Study Exercise Program – Phase 1     75  1. Bridging  Begin this exercise lying on your back in the position demonstrated (staring position). Slowly lift your bottom pushing through your feet, until your knee, hip and shoulder are in a straight line. Tighten your bottom muscles (gluteals) as you do this (end position). Hold for 2 seconds and repeat.           76  2. Transverse abdominal (heel drops)   Begin this exercise lying on your back in the position demonstrated (starting position). Press your low back into the mat/floor and pull your navel into your spine. One at a time, lift one of your heels of the floor. Slowly alternate heels and keep the core engaged.                                        77  3. Clamshells  Begin the exercise by lying on your side in the position demonstrated (starting position). Stack your legs on top of each other and bend your knees to about 45 degrees. Ensure your torso is stable and does not rotate throughout the exercise. Initiate the movement from your hips and hold for 1 second at the top (end position), repeat. Alternate legs after the correct number of repetitions have been completed.                  78   4. Four point kneel w/ hip abduction   Begin this exercise by positioning yourself on all fours with an equal amount of pressure on your hands and knees (starting position). Ensure that your hands positioned directed underneath your shoulders and knees underneath your hips. Also, keep the core engaged and the torso stable. Initiate the movement from the hip by lifting one leg out to the side and hold for 1 second at the top (end position), repeat. Alternate legs after the correct number of repetitions have been completed.                   79  5. Standing on one leg  Begin this exercise by standing upright in the position demonstrated (starting position).  Shift your weight to one leg and bring the other foot of the floor (end position). Maintain your balance and ensure your core is engaged. Try to hold for 30-60 seconds.                          80    The University of British Columbia  Motion Analysis and Biofeedback Laboratory  FAI Strengthening Study Exercise Program – Phase 2      81  1. Clamshells w/ weight cuffs  Begin the exercise by lying on your side in the position demonstrated (starting position). Ensure the weight cuff is securely fastened above the knee. Stack your legs on top of each other and bend your knees to about 45 degrees. Ensure your torso is stable and does not rotate throughout the exercise. Initiate the movement from your hips and hold for 1 second at the top (end position), repeat. Alternate legs after the correct number of repetitions have been.              82  2. Standing hip extension w/ band  Begin this exercise by standing upright in the position demonstrated (starting position). Ensure the resistance band is fastened around the foot of the chair and around your heel/ankle. While holding onto the chair for stability, initiate the movement with your gluteal muscles. Push the heel backwards while keeping the leg straight. Hold for 1 second at the end of the movement (end position). Alternate legs after the correct number of repetitions has been completed.                         83  3. Side steps w/ band   Begin this exercise by standing with your feet about shoulder with apart in the position demonstrated (starting position). Ensure the resistance band is positioned around both ankles. While keeping both knees slightly bent side step down the hall and make sure your feet are facing forward thorough out the movement. Once the correct number of reps are completed, side step back the other way facing the same direction.                                       84  4. Standing hip abduction w/ weight cuffs   Begin this exercise by standing with one hand on the chair (starting position). Ensure that the weight cuff is securely fastened around your ankle. While keeping you leg straight and toes facing forward move your leg sideways. Hold for 1 second at the top of the movement (end position). Alternate legs after the correct number of repetitions have been completed.                   85    The University of British Columbia  Motion Analysis and Biofeedback Laboratory  FAI Strengthening Study Exercise Program – Phase 3      86  1. Squats (alternate with lunges)  Begin the exercise standing with your arms out in front and your weight on your heels in the position demonstrated (starting position). Begin to sit down while keeping your back in a neutral position. Squat towards the floor without letting your knees go past 90 degrees. Hold the position at the bottom for 2 seconds (end position). Push up through the heels and squeeze the gluteal muscle at the top. Repeat until the correct number of repetitions has been completed.             87  1. Lunges (alternate with squats)   Begin this exercise by standing upright in the position demonstrated (starting position). Step forward begin to lower your body as you bend your knee. Concentrate on squeezing your gluteal muscles to push yourself up, and keep the abdominals tight and the lower back in a neutral position. Throughout the exercise, maintain the body in an upright position and avoid leaning forward (end position). This exercise can be done by returning to the start position or by walking down the hall alternating each step.                          88  2. Multi-plane side steps w/ band  Begin this exercise by standing with your feet about shoulder with apart in the position demonstrated (starting position). Ensure the resistance band is positioned around both ankles. While keeping both knees slightly bent side step down the hall and make sure your feet are facing forward thorough out the zig zag movement. Once the correct number of repetitions are completed, side step back the other way in a zig zag formation.                                       89  3. Step ups w/ steps or bench  Begin this exercise by standing with one foot on the step (starting position). Place your weight over the foot on the bench and push through that foot. Hold the position at the top for 2 seconds (end position). While maintaining your balance lower your opposite leg down and tap the floor, repeat. Alternate legs after the correct number of repetitions have been completed.                   90  4. Single leg dead lift  Begin this exercise by standing on one leg in the position demonstrated (starting position). Stand holding weight in front of thighs and place other leg out behind you with the toe lightly touching the floor (or lift it completely off the floor for more of a challenge). Bend from the hips and lower the weight towards the floor. The weight should stay close along the leg throughout the movement (end position). Alternate legs after the correct number of repetitions have been completed.                91  5. Single leg hop  Begin by placing two intersecting pieces of tape on the floor. Stand on one leg as in a quadrant as demonstrated (starting position). Hop from one quadrant to another while maintaining your balance (end position). Ensure to mix up the directions of each hop. Alternate legs after the correct number of repetitions have been completed.              92  Appendix C: Data Hip Flexion Strength Participant ID Baseline (Nm/kg) Follow-up (Nm/kg) FAIEXE01 1.19 1.47 FAIEXE02 1.25 1.40 FAIEXE03 1.77 2.30 FAIEXE04 1.34  FAIEXE05 1.06 1.87 FAIEXE06 2.00 2.04 FAIEXE07 2.02 2.08 FAIEXE08 1.95 2.98 FAIEXE09 1.69 1.94 FAIEXE10 2.05 2.05 FAIEXE11 2.24 2.36 FAIEXE12 1.94 2.61 FAIEXE13 2.80 2.38 FAIEXE14 2.13 2.26 FAIEXE15 2.25 2.35 FAIEXE16 2.13 2.06 FAIEXE17 2.10 1.97 FAIEXE18 1.48 1.34 FAIEXE19 2.44 1.99 FAIEXE20 1.41 1.36 93  Hip Abduction Strength Participant ID Baseline (Nm/kg) Follow-up (Nm/kg) FAIEXE01 0.97 1.31 FAIEXE02 0.98 1.03 FAIEXE03 1.71 1.64 FAIEXE04 1.41  FAIEXE05 1.05 1.39 FAIEXE06 1.49 1.85 FAIEXE07 1.69 1.78 FAIEXE08 1.68 2.08 FAIEXE09 1.36 1.62 FAIEXE10 1.73 1.92 FAIEXE11 1.76 1.80 FAIEXE12 1.41 1.73 FAIEXE13 1.78 1.88 FAIEXE14 1.86 2.08 FAIEXE15 2.13 2.20 FAIEXE16 1.10 1.52 FAIEXE17 1.90 1.85 FAIEXE18 1.07 0.91 FAIEXE19 1.88 1.53 FAIEXE20 1.44 1.52    94  Hip Adduction Strength Participant ID Baseline (Nm/kg) Follow-up (Nm/kg) FAIEXE01 1.14 1.44 FAIEXE02 0.88 0.88 FAIEXE03 1.79 2.07 FAIEXE04 1.55  FAIEXE05 0.74 1.26 FAIEXE06 1.23 1.66 FAIEXE07 1.64 1.63 FAIEXE08 1.52 1.85 FAIEXE09 0.94 1.06 FAIEXE10 2.12 1.95 FAIEXE11 1.49 1.88 FAIEXE12 1.21 1.39 FAIEXE13 1.31 1.45 FAIEXE14 1.75 2.08 FAIEXE15 1.97 1.91 FAIEXE16 1.16 1.05 FAIEXE17 1.55 1.78 FAIEXE18 1.01 0.79 FAIEXE19 1.60 1.60 FAIEXE20 1.62 1.44    95  Hip Extension Strength Participant ID Baseline (Nm/kg) Follow-up (Nm/kg) FAIEXE01 1.14 1.44 FAIEXE02 1.30 1.12 FAIEXE03 1.90 1.83 FAIEXE04 1.78  FAIEXE05 0.80 1.56 FAIEXE06 1.49 2.02 FAIEXE07 2.23 2.30 FAIEXE08 2.18 3.18 FAIEXE09 1.80 1.66 FAIEXE10 1.92 2.40 FAIEXE11 2.10 2.04 FAIEXE12 1.54 2.15 FAIEXE13 2.18 2.21 FAIEXE14 2.41 2.18 FAIEXE15 2.28 2.27 FAIEXE16 1.87 1.97 FAIEXE17 2.23 2.15 FAIEXE18 1.25 1.24 FAIEXE19 2.28 1.20 FAIEXE20 1.59 1.69    96  Hip Internal Rotation Strength Participant ID Baseline (Nm/kg) Follow-up (Nm/kg) FAIEXE01 0.35 0.55 FAIEXE02 0.24 0.47 FAIEXE03 0.32 0.31 FAIEXE04 0.60  FAIEXE05 0.41 0.48 FAIEXE06 0.48 0.50 FAIEXE07 0.42 0.59 FAIEXE08 0.72 0.98 FAIEXE09 0.76 0.74 FAIEXE10 1.26 1.29 FAIEXE11 1.13 0.97 FAIEXE12 0.94 1.19 FAIEXE13 1.08 1.19 FAIEXE14 1.04 1.62 FAIEXE15 0.67 0.96 FAIEXE16 0.66 1.03 FAIEXE17 1.24 1.23 FAIEXE18 0.39 0.58 FAIEXE19 1.25 1.05 FAIEXE20 1.06 1.21    97  Hip External Rotation Strength Participant ID Baseline (Nm/kg) Follow-up (Nm/kg) FAIEXE01 0.54 0.71 FAIEXE02 0.35 0.59 FAIEXE03 0.71 0.62 FAIEXE04 0.77  FAIEXE05 0.50 0.61 FAIEXE06 0.75 0.75 FAIEXE07 0.75 0.86 FAIEXE08 0.69 0.61 FAIEXE09 0.59 0.59 FAIEXE10 0.81 0.83 FAIEXE11 0.81 0.88 FAIEXE12 0.53 0.77 FAIEXE13 1.14 1.03 FAIEXE14 0.84 1.00 FAIEXE15 0.89 0.97 FAIEXE16 0.94 0.99 FAIEXE17 1.20 1.02 FAIEXE18 0.41 0.44 FAIEXE19 1.05 0.61 FAIEXE20 0.73 0.82    98  HOOS Questionnaire Subscales Participant ID Pain Baseline Pain Follow-up Symp Baseline Symp Follow-up ADL Baseline ADL Follow-up Sport Baseline Sport Follow-up QoL Baseline QoL Follow-up FAIEXE01 43 68 50 75 72 87 56 69 38 44 FAIEXE02 53 53 30 35 63 62 25 56 31 31 FAIEXE03 65 60 60 65 63 76 50 44 25 25 FAIEXE04 35  35  43  25  0  FAIEXE05 80 93 80 80 94 97 69 88 63 81 FAIEXE06 63 78 50 50 74 75 56 63 44 44 FAIEXE07 60 58 70 55 69 72 50 63 44 50 FAIEXE08 48 58 50 50 81 87 38 50 0 6 FAIEXE09 85 95 65 75 90 99 44 75 31 44 FAIEXE10 63 70 60 70 65 97 63 75 56 50 FAIEXE11 63 68 65 70 88 85 56 63 6 13 FAIEXE12 60 70 50 70 44 76 50 69 6 0 FAIEXE13 78 65 50 45 87 75 56 50 25 38 FAIEXE14 80 80 65 60 90 91 69 69 50 56 FAIEXE15 65 88 65 90 74 96 56 75 50 56 FAIEXE16 40 68 30 50 41 72 31 38 38 50 FAIEXE17 75 90 60 85 68 96 38 88 31 88 FAIEXE18 68 65 70 60 71 71 63 63 50 50 FAIEXE19 65 73 40 75 75 82 63 63 44 50 FAIEXE20 63 78 55 55 78 88 50 44 38 38    99    Note: * represents statistical significance, p<0.05.    Note: * represents statistical significance, p<0.05. 00.511.522.53Flexion Abduction Adduction Extension InternalrotationExternalrotationNm/kg Movements Hip Muscle Strength BaselineFollow-up0102030405060708090100Pain Symp ADL Sport QoLSubscales HOOS Questionnaire BaselineFollow-up* * * * * * * * 100  Appendix D. Exercise Diary  FAI Strengthening Study       Weekly Diary   Baseline Assessment Date ____/____/______         mm    dd     yyyy   Subject ID Code  __ __ __ 101  INSTRUCTIONS FOR YOUR EXERCISE DIARY  You will perform your exercises a total of 4 times per week. On days when you visit Jerrad Guenther, you will NOT be required to perform your exercises at home for that day. Instead, you will document any exercises performed at the University for that day. When filling out your diary for each week, start by indicating in the top left hand corner of the chart the date of the Monday for that week. For example, if your Week 1 begins on Sunday, October 24th, write that date in the box. The sheet for Week 2 will then have Sunday, October 31st, and so on until you have completed all ten weeks. Also denote what day you attended your rehabilitation visit in the space provided under the chart. After completing your exercises each day, simply place a check mark (√) beside each exercise completed for that particular day. Additionally, denote the resistance that you used (for example, the weight of the cuff) for that week in the space provided. Lastly, denote how many sets and how many repetitions (example, 3 sets of 10) in the spaces provided. Your certified kinesiologist (Jerrad Guenther) will be the only one able to safely increase the amount of resistance that you are using. Please do not increase the weight yourself. Instead, communicate with Jerrad if you feel that the weight is too light. It is normal to feel a little discomfort when commencing a new exercise program – this is usually temporary and should subside within a day or two as your body adapts. If your pain increases significantly, or if you encounter pain in a new area (eg. your back or your knee), please telephone Jerrad Guenther at (604) xxx-xxxx. Please also document any adverse effects (including back pain) that you may experience as well as changes to your treatment regimen or medications in the spaces provided. If your hip joint symptoms change (better or worse), please also describe the changes in the space provided.                102  FAI Strengthening Study: WEEK ONE Please complete the dosage and resistance that you used to perform each exercise. Please tick which days you did your exercises. Enter the day of the week in the grey boxes. mm/dd/yyyy: ____/____/_____ Day of week: Exercise Dosage Weight Sun Mon Tues Wed Thur Fri Sat 1.  Bridging _3_ sets of _10_ 0 kgs        2.  TA heel drops _3_ sets of _10_        0 kgs        3.  Clamshells _3_ sets of _10_        0 kgs        4.  Lying hip abduction/ 4 pt. kneel hip abduction _3_ sets of _10_        0 kgs        5. Standing on one leg _3_ sets of _10_         0 kgs              What day was your visit with the kinesiologist? _______________________________________ Did you suffer any adverse effects (including back pain) from the exercises this week?              yes  no If yes, describe:          Did your hip joint symptoms change this week?                                                          yes    no If yes, describe:         Did you have any new treatments for your hip this week?            yes    no If yes, describe:        103   Did you change your medications at all this week?            yes    no If yes, describe:        Note: Weeks 2-10 have been excluded from the appendix as the questions and table format are similar to this week 1 example.                       104  Appendix E: Permission for Images Permission for Images Jerrad, You have permission to use the two images requested from OrthoInfo “Femoroacetabular Impingement (FAI)” provided:  Use is limited to publication in your thesis  You use the following credit line directly below the figures: Reproduced with permission from OrthoInfo. ©American Academy of Orthopaedic Surgeons. http://orthoinfo.aaos.org. Please respond to this email, accepting the terms of use. Sincerely, Paulette Wirkus Publications Coordinator for Joan Golembiewski Manager, Publications & Licensing 847-xxx-xxxx  

Cite

Citation Scheme:

        

Citations by CSL (citeproc-js)

Usage Statistics

Share

Embed

Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                        
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            src="{[{embed.src}]}"
                            data-item="{[{embed.item}]}"
                            data-collection="{[{embed.collection}]}"
                            data-metadata="{[{embed.showMetadata}]}"
                            data-width="{[{embed.width}]}"
                            async >
                            </script>
                            </div>
                        
                    
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:
http://iiif.library.ubc.ca/presentation/dsp.24.1-0135607/manifest

Comment

Related Items