Recruitment and baseline characteristics of young adults at risk of early-onset knee osteoarthritis after ACL reconstruction in the SUPER-Knee trial.

Objectives: The study aims to (1) report the process of recruiting young adults into a secondary knee osteoarthritis prevention randomised controlled trial (RCT) after anterior cruciate ligament reconstruction (ACLR); (2) determine the number of individuals needed to be screened to include one participant (NNS) and (3) report baseline characteristics of randomised participants. Methods: The SUpervised exercise-therapy and Patient Education Rehabilitation (SUPER)-Knee RCT compares SUPER and minimal intervention for young adults (aged 18-40 years) with ongoing symptoms (ie, mean score of <80/100 from four Knee injury and Osteoarthritis Outcome Score subscales (KOOS4)) 9-36 months post-ACLR. The NNS was calculated as the number of prospective participants screened to enrol one person. At baseline, participants provided medical history, completed questionnaires (demographic, injury/surgery, rehabilitation characteristics) and underwent physical examination. Results: 1044 individuals were screened to identify 567 eligible people, from which 184 participants (63% male) enrolled. The sample of enrolled participants was multicultural (29% born outside Australia; 2% Indigenous Australians). The NNS was 5.7. For randomised participants, mean±SD age was 30±6 years. The mean body mass index was 27.3±5.2 kg/m2, with overweight (43%) and obesity (21%) common. Participants were, on average, 2.3 years post-ACLR. Over half completed <8 months of postoperative rehabilitation, with 56% having concurrent injury/surgery to meniscus and/or cartilage. The most affected KOOS (0=worst, 100=best) subscale was quality of life (mean 43.7±19.1). Conclusion: Young adults post-ACLR were willing to participate in a secondary osteoarthritis prevention trial. Sample size calculations should be multiplied by at least 5.7 to provide an estimate of the NNS. The SUPER-Knee cohort is ideally positioned to monitor and intervene in the early development and trajectory of osteoarthritis. Trial registration number: ACTRN12620001164987.

Defining hip osteoarthritis feature prevalence, severity, and change using the Scoring of Hip Osteoarthritis with MRI (SHOMRI).

OBJECTIVE: To define the reporting of Scoring Hip Osteoarthritis with MRI (SHOMRI) feature prevalence and severity, and to develop criteria to monitor feature change in longitudinal investigations. METHODS: Twenty-five participants (50 hips) of the femoroacetabular impingement and hip osteoarthritis cohort study underwent baseline and 2-year follow-up 3 T hip MRIs. Eight hip OA features were assessed using the SHOMRI. All MRIs were read paired with knowledge of timepoint by two blinded musculoskeletal radiologists. We provide definitions to report SHOMRI feature prevalence, severity, and longitudinal change. RESULTS: We report clear definitions for SHOMRI feature prevalence, severity, and change. When we applied the definitions to the studied cohort, we could detect the prevalence, severity, and change of hip OA features. For example, 88% of hips had labral tears (34% graded as severe tears) and 76% had cartilage defects (42% graded as full thickness). Over 70% of hips had feature change over 2 years, highlighting the sensitivity of SHOMRI definitions to assess longitudinal change of hip OA features. Intra-reader reliability was almost perfect (weighted (w)-kappa 0.86 to 1.00), with inter-reader reliability substantial to almost perfect (w-kappa 0.80 to 1.00). CONCLUSION: This study is the first to provide definitions to report SHOMRI feature prevalence, severity, and change. The proposed definitions will enable comparison between hip MRI studies and improve our understanding of hip OA pathogenesis.

How effective are exercises delivered digitally (requiring internet), amongst patients with hip or knee osteoarthritis? A systematic review and meta-analysis.

OBJECTIVE: The aim of this systematic review and meta-analysis is to describe the effect of digitally delivered exercise on pain, physical function and quality of life (QoL) for people with knee or hip osteoarthritis (OA). METHODS: Articles were eligible for inclusion if they were of a randomized control trial that evaluated the prescription of digitally delivered exercise (requiring the internet) in people with symptomatic primary hip and/or knee OA. Risk of bias was assessed using the Physiotherapy Evidence Database scale, and levels of evidence were assessed according to Grading of Recommendations Assessment, Development and Evaluation. RESULTS: Digitally delivered exercise was delivered via synchronous and asynchronous methods (or a combination of both). Digitally delivered exercise was superior to education only for pain and physical function, with high-quality evidence for quality-of-life outcomes in the long-term (standardized mean difference -0.35, 95% confidence interval -0.59 to -0.12, P = 0.003) in people with knee OA. Furthermore, there was very low to low-quality evidence that digitally delivered exercise was comparable to face-to-face delivery in the short and long-term for people with hip or knee OA and comparable in the medium-term for people with knee OA only. DISCUSSION: The review demonstrated very low to low-quality evidence that digitally delivered exercise was comparable to face-to-face delivery for pain, function and QoL. In the absence of higher-level evidence, we would provisionally recommend that healthcare providers offer the choice of face-to-face or digitally delivered exercise intervention for people with hip or knee OA. Further work is required to understand these programs' reach, access, uptake and implementation across diverse population groups.

The association between lateral hip muscle size/intramuscular fat infiltration and hip strength in active young adults with long standing hip/groin pain.

OBJECTIVES: To investigate associations between lateral hip muscle size/intramuscular fat infiltration (MFI) and hip strength in active young adults with longstanding hip/groin pain. DESIGN: Cross-sectional study. SETTING: University/Clinical. PARTICIPANTS: Sub-elite soccer and Australian Football players (n = 180; 37 female) with long standing hip/groin pain. MAIN OUTCOME MEASURES: Muscle size (volume) and MFI of gluteus maximus, medius, and minimis, and tensor fascia latae (TFL) were assessed using magnetic resonance imaging. Isometric hip strength was measured with handheld dynamometry. Associations between muscle size/MFI were assessed using linear regression models, adjusted for body mass index and age, with sex-specific interactions. RESULTS: Positive associations were identified between lateral hip muscle volume and hip muscle strength, particularly for gluteus maximus and gluteus minimus volume. For all muscles, hip abduction was associated with an increase in strength by up to 0.69 N (R2 ranging from 0.29 to 0.39). These relationships were consistent across sexes with no sex interactions observed. No associations were found between MFI and strength measures. CONCLUSION: Greater lateral hip muscle volumes are associated with greater hip strength in active young adults with long standing hip/groin pain, irrespective of sex. Gluteus maximus and minimus volume showed the most consistent relationships with hip strength across multiple directions.

Hip Muscle Strength, Range of Motion, and Functional Performance in Young Elite Male Australian Football Players.

CONTEXT: Hip and groin injuries are common in field sports such as football, with measurement of hip strength and range of motion (ROM) recommended for assessment of these conditions. We aimed to report hip strength, hip ROM, and functional task performance in young elite Australian football athletes. DESIGN: Cross-sectional study. METHODS: Fifty-eight newly drafted Australian Football League athletes completed hip abduction, adduction, internal rotation, external rotation, and flexion strength testing with an adjustable stabilized or hand-held dynamometer. Hip internal rotation and external rotation, bent knee fall out, and ankle dorsiflexion ROM were also measured. Players completed hop for distance, side bridge, and star excursion balance functional tests. We compared findings between the dominant and nondominant limbs. RESULTS: We found small deficits unlikely to be clinically meaningful in the dominant limb for hip abduction and adduction strength, and a small deficit in the nondominant limb for external rotation strength and side bridge time. Athletes had lower hip internal rotation (mean difference 2.56°; 95% confidence interval, 0.87 to 4.26) and total rotation ROM (2.03°; 95% confidence interval, 0.06 to 4.01) on the dominant limb. CONCLUSIONS: There were no meaningful differences between dominant and nondominant limbs for hip strength, ROM, or functional tests. Our results may be used for benchmarking young male Australian football athletes when targeting optimal strength and returning from injury.

Football Players With Hip Dysplasia: The Relationship Between Muscle Strength, Functional Performance, Self-reported Sport and Recreation, Cartilage Defects, and Sex. A Cross-sectional Study.

OBJECTIVE: In symptomatic football players with hip dysplasia, we aimed to explore the relationships between self-reported sport and recreation ability and (1) hip muscle strength, (2) functional performance, and investigate if these relationships were modified by sex or cartilage defects. METHODS: In this cross-sectional study, football players (n = 50) with longstanding (>6 months) hip and/or groin pain, a positive flexion/adduction/internal rotation test, and a lateral-center-edge angle <25° were included. Hip muscle strength and functional performance were assessed. Self-reported sport and recreation ability was quantified using the sports and recreational subscales from the International Hip Outcome Tool-33 (iHOT-Sport) and the Copenhagen Hip and Groin Outcome Score (HAGOS-Sport). Relationships were evaluated using regression models with sex and cartilage defects as potential effect modifiers. RESULTS: There was a positive linear relationship between the one-leg-rise test and the iHOT-Sport subscale (ß = 0.61; 95% CI: 0.09, 1.14). A polynomial (concave) relationship was found between peak eccentric adduction strength and the HAGOS-Sport subscale (ß = -30.88; 95% CI: -57.78, -3.99). Cartilage defects modified the relationship between peak isometric adduction strength and HAGOS-Sport, with those with cartilage defects having a polynomial (convex) relationship (ß = 36.59; 95% CI: 12.74, 60.45), and those without cartilage defects having no relationship. CONCLUSION: One-leg-rise performance and adduction strength were associated with self-reported sport and recreation ability, indicating a possible relationship between physical function, hip joint structure, and sport and recreation ability in football players with hip dysplasia. J Orthop Sports Phys Ther 2023;53(10):1-8. Epub: 8 September 2023. doi:10.2519/jospt.2023.12026.

Does the one-leg rise test reflect quadriceps strength in individuals following anterior cruciate ligament reconstruction?

OBJECTIVE: To explore if one-leg rise test performance is associated with quadriceps strength following anterior cruciate ligament reconstruction (ACLR). DESIGN: Cross-sectional. PARTICIPANTS: 100 individuals (50 females, 50 males) aged 18-40 years, 9-36 months post-ACLR with ongoing knee symptoms (KOOS4 <80/100). MAIN OUTCOME MEASURES: Number of one-leg rise repetitions (using an adjustable-height plinth) and isometric quadriceps strength using isokinetic dynamometry (60° flexion, normalised to body mass). Multivariable fractional polynomial regression models adjusted for sex explored relationships between one-leg rise performance (repetitions) and quadriceps strength (Nm/kg) for each limb. RESULTS: A non-linear, increasing association between one-leg rise performance and quadriceps strength was observed, with the rate of increase attenuating at higher values of one-leg rise performance. Similar relationships were observed in the ACLR (ß = 0.15, 95%CI 0.10 to 0.20; adjusted r2 = 0.51) and contralateral limb (ß = 0.14, 95%CI 0.08 to 0.19; r2 = 0.42). CONCLUSION: The one-leg rise test can be an indicator of quadriceps strength in individuals after ACLR, enabling clinicians to easily monitor quadriceps strength recovery without specialised equipment. With the relationship between one-leg rise performance and quadriceps strength attenuating with a larger number of one-leg rises achieved, other factors (e.g., motivation, endurance) likely contribute to one-leg rise performance at higher values.

Does hip muscle strength and functional performance differ between football players with and without hip dysplasia?

OBJECTIVE: To compare hip muscle strength and functional performance in football players with and without hip dysplasia and investigate if the relationships were modified by sex. DESIGN: Cross-sectional study. METHODS: This study compared football players with hip dysplasia (HD group) and without hip dysplasia (control group). Hip muscle strength (Nm/kg) and functional task performance were assessed in both groups. Linear regression with generalized estimating equations were used to assess differences between groups. Sex was assessed as a potential effect modifier. RESULTS: 101 football players were included (HD group, n = 50, control group, n = 51). There was no difference in hip muscle strength or functional performance between the HD group and the control group. Results ranged from hip extension strength (Estimate -0.13.95%CI: 0.29 to 0.02, P = 0.087) to hip external rotation strength (Estimate 0.00.95%CI: 0.05 to 0.05, P = 0.918). No relationships were modified by sex or age. CONCLUSIONS: Similar levels of hip muscle strength and functional performance were found in active football players with and without hip dysplasia. These findings differ from other studies. This may be due to our cohort having less advanced hip dysplasia than the surgical populations that have been previously investigated, or due to a beneficial effect of football participation on muscle strength and functional performance in people with hip dysplasia.

Are hip biomechanics during running associated with symptom severity or cam morphology size in male football players with FAI syndrome?

BACKGROUND: Femoroacetabular impingement (FAI) syndrome is considered a motion-related condition. Little is known about the influence of symptom severity and cam morphology on hip biomechanics for individuals with FAI syndrome. RESEARCH QUESTION: Are hip biomechanics during running associated with symptom severity or cam morphology size in male football players with FAI syndrome? METHODS: Forty-nine male, sub-elite football (soccer or Australian football) players (mean age= 26 years) with FAI syndrome completed the International Hip Outcome Tool-33 (iHOT-33) and Copenhagen Hip and Groin Outcome Score (HAGOS) and underwent radiographic evaluation. Biomechanical data were collected during overground running (3-3.5 m∙s-1) using three-dimensional motion capture technology and an embedded force plate. Various discrete hip angles and impulses of joint moments were analysed during the stance phase. Linear regression models investigated associations between running biomechanics data (dependent variables) and iHOT-33 and HAGOS scores and cam morphology size (independent variables). RESULTS: Hip joint angles during running were not associated with symptom severity in football players with FAI syndrome. A positive association was found between the impulse of the hip external rotation moment and HAGOS-Sport scores, such that a smaller impulse magnitude occurred with a lower HAGOS-Sport score (0.026 *10-2 [95%CI <0.001 *10-2 to 0.051 *10-2], P = 0.048). Larger cam morphology was associated with a greater peak hip adduction angle at midstance (0.073 [95%CI 0.002-0.145], P = 0.045). SIGNIFICANCE: Hip biomechanics during running did not display strong associations with symptom severity or cam morphology size in male football players with FAI syndrome who were still participating in training and match play. Future studies might consider investigating associations during tasks that utilise end range hip joint motion or require greater muscle forces.

SUpervised exercise-therapy and Patient Education Rehabilitation (SUPER) versus minimal intervention for young adults at risk of knee osteoarthritis after ACL reconstruction: SUPER-Knee randomised controlled trial protocol.

INTRODUCTION: Anterior cruciate ligament injury and reconstruction (ACLR) is often associated with pain, functional loss, poor quality of life and accelerated knee osteoarthritis development. The effectiveness of interventions to enhance outcomes for those at high risk of early-onset osteoarthritis is unknown. This study will investigate if SUpervised exercise-therapy and Patient Education Rehabilitation (SUPER) is superior to a minimal intervention control for improving pain, function and quality of life in young adults with ongoing symptoms following ACLR. METHODS AND ANALYSIS: The SUPER-Knee Study is a parallel-group, assessor-blinded, randomised controlled trial. Following baseline assessment, 184 participants aged 18-40 years and 9-36 months post-ACLR with ongoing symptoms will be randomly allocated to one of two treatment groups (1:1 ratio). Ongoing symptoms will be defined as a mean score of <80/100 from four Knee injury and Osteoarthritis Outcome Score (KOOS4) subscales covering pain, symptoms, function in sports and recreational activities and knee-related quality of life. Participants randomised to SUPER will receive a 4-month individualised, physiotherapist-supervised strengthening and neuromuscular programme with education. Participants randomised to minimal intervention (ie, control group) will receive a printed best-practice guide for completing neuromuscular and strengthening exercises following ACLR. The primary outcome will be change in the KOOS4 from baseline to 4 months with a secondary endpoint at 12 months. Secondary outcomes include change in individual KOOS subscale scores, patient-perceived improvement, health-related quality of life, kinesiophobia, physical activity, thigh muscle strength, knee function and knee cartilage morphology (ie, lesions, thickness) and composition (T2 mapping) on MRI. Blinded intention-to-treat analyses will be performed. Findings will also inform cost-effectiveness analyses. ETHICS AND DISSEMINATION: This study is approved by the La Trobe University and Alfred Hospital Ethics Committees. Results will be presented in peer-reviewed journals and at international conferences. TRIAL REGISTRATION NUMBER: ACTRN12620001164987.

Does Femoroacetabular Impingement Syndrome Affect Self-Reported Burden in Football Players With Hip and Groin Pain?

BACKGROUND: It is unknown if football players with femoroacetabular impingement (FAI) syndrome report worse burden than those with other causes of hip/groin pain, and to what extent this is mediated by cartilage defects and labral tears. HYPOTHESIS: Football players with FAI syndrome would report worse burden than other symptomatic players, with the effect partially mediated by cartilage defects and/or labral tears. STUDY DESIGN: Cross-sectional study. LEVEL OF EVIDENCE: Level 4. METHODS: Football (soccer and Australian football) players (n = 165; 35 women) with hip/groin pain (≥6 months and positive flexion-adduction-internal rotation test) were recruited. Participants completed 2 patient-reported outcome measures (PROMs; the International Hip Outcome Tool-33 [iHOT-33] and Copenhagen Hip and Groin Outcome Score [HAGOS]) and underwent hip radiographs and magnetic resonance imaging (MRI). FAI syndrome was determined to be present when cam and/or pincer morphology were present. Cartilage defects and labral tears were graded as present or absent using MRI. Linear regression models investigated relationships between FAI syndrome (dichotomous independent variable) and PROM scores (dependent variables). Mediation analyses investigated the effect of cartilage defects and labral tears on these relationships. RESULTS: FAI syndrome was not related to PROM scores (unadjusted b values ranged from -4.693 (P = 0.23) to 0.337 (P = 0.93)) and cartilage defects and/or labral tears did not mediate its effect (P = 0.22-0.97). CONCLUSION: Football players with FAI syndrome did not report worse burden than those with other causes of hip/groin pain. Cartilage defects and/or labral tears did not explain the effect of FAI syndrome on reported burden. CLINICAL RELEVANCE: FAI syndrome, cartilage defects, and labral tears were prevalent but unrelated to reported burden in symptomatic football players.

Football players with long standing hip and groin pain display deficits in functional task performance.

OBJECTIVES: i) Compare functional task performance between football players with and without hip/groin pain. ii) Explore the relationship, and sex-specific effects, between functional tasks and the Copenhagen Hip and Groin Outcome Score (HAGOS) in players with hip/groin pain. DESIGN: Cross-sectional. SETTING: Laboratory. PARTICIPANTS: 183 (38 women) football players with a self-reported history of >6months of non-time-loss hip/groin pain and a positive flexion-adduction-internal rotation test, and 61 (14 women) asymptomatic players. MAIN OUTCOME: Participants completed the hop-for-distance (HFD), one leg rise (OLR), side bridge (SB) endurance, and HAGOS. Study aims were assessed using linear models, controlling for body mass index and age, incorporating sex-specific interaction terms. RESULTS: Players with hip/groin pain could not hop as far (adjusted mean difference: -9 cm, 95% CI: -15 cm to -2cm, P=0.012) and completed fewer OLR repetitions (adjusted mean difference -7, 95% confidence interval -11 to -3 repetitions, P=0.001) compared to asymptomatic players. Symptomatic women, but not symptomatic men, with worse HAGOS scores had lower SB endurance. Independent of sex, football players with worse HAGOS scores could not hop as far and completed fewer OLR repetitions. CONCLUSION: Football players with hip/groin pain demonstrated deficits in HFD and OLR with the performance of these tasks associated with their HAGOS results. The study identifies potential impairments that can be targeted as a component of rehabilitation programs for football players with hip/groin pain.

Relationship between hip muscle strength and hip biomechanics during running in people with femoroacetabular impingement syndrome.

BACKGROUND: Hip muscle weakness and altered hip biomechanics during walking are often observed in people with femoroacetabular impingement syndrome, although little is known about biomechanics during higher impact tasks. The aim of our study was to explore relationships between hip muscle strength and hip biomechanics during running in people with femoroacetabular impingement syndrome, including exploring sex as an effect-modifier of this relationship. METHODS: Forty-two adults with unilateral femoroacetabular impingement syndrome (20 females; age 18-50 years; alpha angle ≥60°) completed assessments of hip muscle strength and hip biomechanics during running. Strength was assessed using a hand-held dynamometer for the hip flexors, extensors, abductors, adductors, internal rotators, and external rotators. Hip biomechanics were assessed during overground running (3-3.5 m/s) using three-dimensional motion capture and a force plate. Linear models assessed the relationships between hip strength and hip biomechanics of the symptomatic limb, controlling for body mass and running velocity along with an interaction term (strength*sex). FINDINGS: A significant negative relationship was observed between hip external rotator strength and hip frontal plane range of motion (i.e., excursion), independent of sex (estimate = -0.039, 95%CI -0.071 to -0.008, P = 0.02). Four sex-specific interactions were observed, with a significant positive relationship between hip external rotator strength and peak hip extension moment in women (estimate = -0.413, 95%CI -0.713 to -0.114, P = 0.01) but not in men. INTERPRETATION: We found significant relationships between hip external rotator strength and stance phase running biomechanics, providing further understanding on two impaired physical measures that may inform exercise-based management strategies in femoroacetabular impingement syndrome.

Are cam morphology size and location associated with self-reported burden in football players with FAI syndrome?

Cam morphology size and location might affect the severity of reported burden in people with femoroacetabular impingement (FAI) syndrome. We investigated the relationship between cam morphology size (i.e., alpha angle) and self-reported hip/groin burden (i.e., scores for the International Hip Outcome Tool-33 (iHOT-33) and Copenhagen Hip and Groin Outcome Score (HAGOS)), examined separately for the anteroposterior pelvis (AP) and Dunn 45° radiographs in football players with FAI syndrome. In total, 118 (12 women) subelite football (soccer or Australian football) players with FAI syndrome with cam morphology (alpha angle ≥60°) participated. One blinded assessor quantified superior and anterosuperior cam morphology size by measuring alpha angles for the AP and Dunn 45° radiographs, respectively. Linear regression models investigated relationships between alpha angle (continuous independent variable, separately measured for the AP and Dunn 45° radiographs) and iHOT-33 and HAGOS scores (dependent variables). Larger anterosuperior cam morphology (seen on the Dunn 45° radiograph) was associated with lower (i.e., worse) scores for the iHOT-Total, iHOT-Symptoms, iHOT-Job, and iHOT-Social subscales (unadjusted estimate range -0.553 to -0.319 [95% confidence interval -0.900 to -0.037], p = 0.002 to 0.027), but not the iHOT-Sport (p = 0.459) nor any HAGOS scores (p = 0.110 to 0.802). Superior cam morphology size (measured using the AP radiograph) was not associated with any iHOT-33 or HAGOS scores (p = 0.085 to 0.975). Larger anterosuperior cam morphology may be more relevant to pain and symptoms in football players with FAI syndrome than superior cam morphology, warranting investigation of its effects on reported burden and hip disease over time.

Running biomechanics in football players with and without hip and groin pain. A cross-sectional analysis of 116 sub-elite players.

OBJECTIVE: Examine whether football players with hip and/or groin (hip/groin) pain have impaired running biomechanics when compared to pain-free players, analysing men and women independently. DESIGN: Cross-sectional. SETTING: Biomechanics laboratory. PARTICIPANTS: Seventy-eight (62 men, 16 women) football players with >6months of hip/groin pain and a positive flexion-adduction-internal rotation test and 38 (25 men, 13 women) asymptomatic players. MAIN OUTCOME MEASURES: Pelvis angles and hip, knee, and ankle joint angles and moments were analysed during the stance phase of overground running at 3-3.5 m⋅s-1. Continuous joint angle and moment data were compared between symptomatic and asymptomatic football players of the same sex using statistical parametric mapping. Joint moment impulses (area under the curve) were compared between groups using linear regression models. RESULTS: Symptomatic football players did not display significant differences in pelvis angles or lower-limb joint angles, moments, or moment impulses during the stance phase of running, when compared to asymptomatic players of the same sex. CONCLUSION: Our large sample of football players with hip/groin pain who were still participating in competitive sport displayed similar running biomechanics to asymptomatic players. Impaired running biomechanics might exist in people with worse hip/groin pain, warranting future investigation.

The Validity, Reliability, and Responsiveness of the International Hip Outcome Tool-33 (iHOT-33) in Patients With Hip and Groin Pain Treated Without Surgery.

BACKGROUND: The International Hip Outcome Tool-33 (iHOT-33) was developed to evaluate patients seeking surgery for hip and/or groin (hip/groin) pain and may not be appropriate for those seeking nonsurgical treatment. PURPOSE: To evaluate the psychometric properties of the iHOT-33 total (iHOT-Total) score and all subscale scores in adults with hip/groin pain who were not seeking surgery. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: Patients with hip/groin pain who were not seeking surgery were recruited from 2 ongoing studies in Australia. Semistructured one-on-one interviews assessed content validity. Construct validity was assessed by testing hypothesized correlations between iHOT-33 and Copenhagen Hip and Groin Outcome Score (HAGOS) subscale scores. Test-retest reliability was assessed in patients not undertaking treatment and who reported "no change" in their Global Rating of Change (GROC) score at 6-month follow-up. Scores were reliable at group and individual levels if intraclass correlation coefficients (ICCs) were ≥0.80 and ≥0.90, respectively. Scores were responsive if Spearman rank correlations (ρ) between the change in the iHOT-33 score and the GROC score were ≥0.40. RESULTS: In total, 278 patients with hip/groin pain (93 women; mean age, 31 years) and 55 pain-free control participants (14 women; mean age, 29 years) were recruited. The iHOT-33 demonstrated acceptable content validity. Construct validity was acceptable, with all hypothesized strong positive correlations between iHOT-33 and HAGOS subscale scores confirmed (r range, 0.60-0.76; P < .001), except for one correlation between the iHOT-Sport and HAGOS-Sport (r = .058; P < .001). All scores were reliable at the group level, except for the iHOT-33 job subscale (iHOT-Job) (ICC range, 0.78-0.88 [95% CI, 0.60-0.93]). None of the subscales met the criteria for adequate reliability for use at the individual level (all ICCs <0.90). Minimal detectable change values (group level) ranged from 2.3 to 3.7 (95% CI, 1.7-5.0). All iHOT-33 subscale scores were responsive (ρ range, 0.40-0.58; P≤ .001), except for the iHOT-Job in patients not undertaking treatment (ρ = 0.27; P = .001). CONCLUSION: All iHOT-33 subscale scores were valid for use in patients with hip/groin pain who were not seeking surgery. Acceptable test-retest reliability was found for all subscale scores at the group level, except the iHOT-Job. All subscale scores, excluding the iHOT-Job, were responsive, regardless of undertaking physical therapist-led treatment or no treatment.

Physiotherapist-led treatment for femoroacetabular impingement syndrome (the PhysioFIRST study): a protocol for a participant and assessor-blinded randomised controlled trial.

INTRODUCTION: This double-blind, randomised controlled trial (RCT) aims to estimate the effect of a physiotherapist-led intervention with targeted strengthening compared with a physiotherapist-led intervention with standardised stretching, on hip-related quality of life (QOL) or perceived improvement at 6 months in people with femoroacetabular impingement (FAI) syndrome. We hypothesise that at 6 months, targeted strengthening physiotherapist-led treatment will be associated with greater improvements in hip-related QOL or greater patient-perceived global improvement when compared with standardised stretching physiotherapist-led treatment. METHODS AND ANALYSIS: We will recruit 164 participants with FAI syndrome who will be randomised into one of the two intervention groups, both receiving one-on-one treatment with the physiotherapist over 6 months. The targeted strengthening physiotherapist-led treatment group will receive a personalised exercise therapy and education programme. The standardised stretching physiotherapist-led treatment group will receive standardised stretching and personalised education programme. Primary outcomes are change in hip-related QOL using International Hip Outcome Tool-33 and patient-perceived global improvement. Secondary outcomes include cost-effectiveness, muscle strength, range of motion, functional task performance, biomechanics, hip cartilage structure and physical activity levels. Statistical analyses will make comparisons between both treatment groups by intention to treat, with all randomised participants included in analyses, regardless of protocol adherence. Linear mixed models (with baseline value as a covariate and treatment condition as a fixed factor) will be used to evaluate the treatment effect and 95% CI at primary end-point (6 months). ETHICS AND DISSEMINATION: The study protocol was approved (La Trobe University Human Ethics Committee (HEC17-080)) and prospectively registered with the Australian New Zealand Clinical Trials Registry. The findings of this RCT will be disseminated through peer reviewed scientific journals and conferences. Patients were involved in study development and will receive a short summary following the completion of the RCT. TRIAL REGISTRATION NUMBER: ACTRN12617001350314.

Lower-limb work during high- and low-impact activities in hip-related pain: Associations with sex and symptom severity.

BACKGROUND: Hip-related pain (HRP) is described as a movement-related disorder. However, little attention is given to the way people with HRP move, especially in populations still participating in sport. Thus, limiting our understanding of movementbased impairments in HRP and their potential relationships with pain/symptoms. RESEARCH QUESTION: (1) What are the differences in absolute and relative amounts of positive and negative lower-limb joint work during walking and the single-leg drop jump (SLDJ) in football players with and without HRP? (2) What are the relationships between lower-limb joint work and HRP burden? METHODS: 88 football players with HRP and 30 control football players were recruited. Positive and negative work done by the hip, knee, and ankle (and each joint's relative contribution to total work done) were calculated. The effect of sex on the relationship between HRP and work done, as well as the association between work done and International Hip Outcome Tool (iHOT33) scores, were assessed using linear and beta regressions models. RESULTS: Walking: No joint work variables were significantly different between groups, nor were any relationships with iHOT33 scores evident. SLDJ: The knee's relative contribution to total lower-limb negative work done was 37.7 % and 42.4 % for women with and without HRP, respectively (P = 0.04). The iHOT33 was significantly associated with positive (P = 0.03 to <0.01) and negative (P = 0.02 to <0.01) work done by the hip as well as negative work done by the ankle (P = 0.03 to 0.01), independent of sex. SIGNIFICANCE: Only one significant between-group comparison was revealed, involving the knee in female football players. In addition, football players with a greater selfreported burden of HRP tended to display lower hip joint work during the SLDJ. Rehabilitation programs could be targeted to address these impairments and normalize work done during high impact tasks in the management of HRP.