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Trotzky Z, Muffly B, Cao N, Sink E. Surgical Hip Dislocation in the Era of Hip Arthroscopy Demonstrates High Survivorship and Improvements in Patient-reported Outcomes for Complex Femoroacetabular Impingement. Clin Orthop Relat Res 2024:00003086-990000000-01543. [PMID: 38513108 DOI: 10.1097/corr.0000000000003032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 02/15/2024] [Indexed: 03/23/2024]
Abstract
BACKGROUND Over the past decade, hip arthroscopy has become more commonly used in the treatment of patients with femoroacetabular impingement (FAI) as well as those with many other intra-articular hip pathologies. As such, the indications for open surgical hip dislocation have narrowed to include complex intra-articular and extra-articular bony morphologies and revision hip preservation. Although surgical hip dislocation has been established as an effective approach, previous research using contemporary indications has been limited primarily to smaller cohorts with short-term follow-up. Furthermore, factors associated with reoperation, conversion arthroplasty, and not achieving clinical improvement remain ambiguous. QUESTIONS/PURPOSES At a minimum of 2 years of follow-up in patients treated for FAI with surgical hip dislocation, (1) how much did patient-reported outcome measures (PROMs) improve, and what percentage of patients achieved the minimum clinically important difference (MCID) and patient-acceptable symptom state (PASS)? (2) What was the survivorship free from reoperation of the hip for any reason? (3) What was the survivorship free from conversion to arthroplasty (THA or hip resurfacing)? METHODS Between February 2011 and April 2021, 211 patients were treated at one academic institution with surgical dislocation and osteoplasty of the femoral head-neck junction or greater trochanter for FAI. Of these, patients with concomitant diagnoses including Legg-Calvé-Perthes disease, slipped capital femoral epiphysis, osteochondritis dissecans, a benign tumor, or another neurologic or metabolic disorder were excluded. This yielded 74% (156 of 211) of patients as potentially eligible. A further 12% (18 of 156) of patients without postoperative PROMs were excluded, and another 13% (21 of 156) were lost before the minimum study follow-up of 2 years, leaving 75% (117) for analysis at a median of 4.9 years (range 2 to 12 years) in this retrospective study. A total of 88% of the patients were women (103 of 117), and 40% (47 patients) underwent the procedure as a revision. All patients underwent surgical hip dislocation. Intraoperatively, 66% (77 of 117) of patients demonstrated cam impingement, and the remainder had either pincer impingement or combined cam and pincer; 82% (96 of 117) had some component of extra-articular impingement. To answer our first research question, we obtained PROM scores for the modified Harris hip score (mHHS) and international hip outcome tool 12 (iHOT-12) before surgery and at the most-recent follow-up from our longitudinally maintained institutional database, and we determined the percentage of patients who achieved the MCID or PASS. To answer our second research question, we calculated Kaplan-Meier survivorship free from any reoperation on the hip at 5.8 years (mean follow-up) after the index procedure. To answer our third research question, we calculated the Kaplan-Meier survivorship free from conversion to arthroplasty at 5.8 years. Using univariate logistic regression analysis, factors associated with meeting these defined endpoints were identified. RESULTS At a mean of 6 ± 3 years, the mHHS of patients treated with surgical hip dislocation for FAI who had not had previous surgery on the hip improved from 53 ± 15 to 85 ± 13 (mean difference 31 [95% confidence interval 27 to 36]; p < 0.01) and the mean iHOT-12 score improved from 25 ± 14 to 74 ± 24 (mean difference 49 [95% CI 42 to 56]; p < 0.01). At a mean of 5 ± 3 years, for patients with prior hip surgery, mHHS improved from 55 ± 13 to 79 ± 15 (mean difference 24 [95% CI 18 to 30]; p < 0.01) and iHOT-12 scores improved from 25 ± 16 to 66 ± 26 (mean difference 41 [95% CI 31 to 50]; p < 0.01). The proportion of patients who achieved the MCID for the mHHS was 87% (55 of 63) and 83% (33 of 40), while the proportion who achieved the PASS for the mHHS was 66% (46 of 70) and 51% (24 of 47) for primary and revision surgery, respectively. The proportion of patients who achieved the MCID for the iHOT-12 was 87% (53 of 61) and 83% (33 of 40), while the proportion who achieved the PASS for iHOT-12 was 68% (47 of 69) and 57% (26 of 46) for primary and revision surgery, respectively. Higher lateral center-edge angles (odds ratio 1.2 per 1° [95% CI 1.1 to 1.3]; p < 0.01), a lower acetabular version at 2:00 (OR 0.92 per 1° [95% CI 0.85 to 0.99]; p = 0.05), the absence of a labral tear (OR 0.21 [95% CI 0.06 to 0.79]; p = 0.02), a higher preoperative mHHS (OR 1.1 per 1 point [95% CI 1.02 to 1.2]; p < 0.01), and a higher preoperative iHOT-12 score (OR 1.1 per 1 point [95% CI 1.01 to 1.1]; p = 0.01) were associated with not achieving the MCID. In patients without a history of ipsilateral hip surgery, survivorship free from reoperation at 5.8 years after surgical hip dislocation was 90% (95% CI 82% to 98%). In the setting of prior ipsilateral hip surgery, survivorship free from reoperation at 5.8 years after surgical hip dislocation was 75% (95% CI 60% to 95%). No patients for whom surgical hip dislocation was their primary hip procedure underwent conversion to arthroplasty. Among the revision patient cohort, survivorship free from conversion to arthroplasty at 5.8 years after surgical hip dislocation was 97% (95% CI 91% to 100%). CONCLUSION Surgical hip dislocation effectively improves hip pain and function with high survivorship (free of reoperation or conversion to arthroplasty) for complex intra-articular and extra-articular FAI that is deemed less suitable for arthroscopic treatment, but when the procedure is used in patients who have had prior hip surgery, they should be told that revision surgery is a realistic possibility. If insufficient acetabular coverage is anticipated, acetabular reorientation osteotomy should be considered. Future studies should evaluate long-term survivorship and PROMs in larger patient cohorts, as well as identify other factors associated with reoperation and conversion to arthroplasty. LEVEL OF EVIDENCE Level III, therapeutic study.
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Affiliation(s)
- Zachary Trotzky
- Department of Hip Preservation, Hospital for Special Surgery, New York, NY, USA
| | - Brian Muffly
- Department of Hip Preservation, Hospital for Special Surgery, New York, NY, USA
| | - Nora Cao
- Department of Pediatric Orthopedic Surgery, Hospital for Special Surgery, New York, NY, USA
| | - Ernest Sink
- Department of Hip Preservation, Hospital for Special Surgery, New York, NY, USA
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Kuhns BD, Harris WT, Domb BG. Low Ceiling Effects of the Forgotten Joint Score Compared With Legacy Measures After Joint-Preserving Procedures: A Systematic Review. Arthroscopy 2023; 39:2086-2095. [PMID: 36804458 DOI: 10.1016/j.arthro.2023.01.107] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 01/17/2023] [Accepted: 01/31/2023] [Indexed: 02/23/2023]
Abstract
PURPOSE To determine, in patients undergoing joint preservation procedures, whether the Forgotten Joint Score (FJS) compares favorably with legacy measures. METHODS Medical databases (including PubMed/MEDLINE and Embase databases) were queried for publications with the terms "Forgotten Joint Score" and "hip," "knee," "arthroscopy," or "ACL." Fourteen studies met the inclusion criteria. Methodologic quality was assessed through the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) checklist, and psychometric data were evaluated for ceiling or floor effects, convergent validity, internal consistency, reliability, responsiveness, measurement invariance, and measurement error by 2 fellowship-trained orthopaedic surgeons (B.D.K. and W.T.H.). RESULTS Data were collected from 14 studies using the FJS after joint-preserving procedures in 911 patients (959 joints). Four studies reported strong internal consistency with an average Cronbach α of 0.92. Two studies reported responsiveness with an effect size ranging from 0.6 to 1.16. One study reported reproducibility with an interclass correlation coefficient of 0.9 (95% confidence interval, 0.8-0.9). One study reported measurement error with an minimum detectable change (MDC)individual of 32% and MDCgroup of 4.5%. Studies reported moderate to very strong convergent validity across legacy measures for hip and knee preservation surgery. Ceiling effects were favorable compared with many legacy scores for hip and knee preservation. Three studies reported the minimal clinically important difference whereas 1 study reported the patient acceptable symptomatic state for the FJS. CONCLUSIONS The FJS is a methodologically sound outcome measure used to evaluate patient outcomes after hip and knee preservation surgery with overall low ceiling effects compared with legacy measures. LEVEL OF EVIDENCE Level IV, systematic review of Level III and IV studies.
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Affiliation(s)
- Benjamin D Kuhns
- American Hip Institute Research Foundation, Chicago, Illinois, U.S.A..
| | - W Taylor Harris
- American Hip Institute Research Foundation, Chicago, Illinois, U.S.A
| | - Benjamin G Domb
- American Hip Institute Research Foundation, Chicago, Illinois, U.S.A
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Owen MM, Gohal C, Angileri HS, Hartwell MJ, Plantz MA, Tjong VK, Terry MA. Sex-Based Differences in Prevalence, Outcomes, and Complications of Hip Arthroscopy for Femoroacetabular Impingement: A Systematic Review and Meta-analysis. Orthop J Sports Med 2023; 11:23259671231188332. [PMID: 37547081 PMCID: PMC10403993 DOI: 10.1177/23259671231188332] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 04/11/2023] [Indexed: 08/08/2023] Open
Abstract
Background Trends between the sexes have been reported regarding prevalence, patient-reported outcomes (PROs), and complications of hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS), yet current results lack consensus. Purpose To evaluate sex-based differences after HA for FAIS in (1) prevalence of cam and pincer morphology in FAIS and (2) PROs, pain scores, and postoperative complication rates. Study Design Systematic review; Level of evidence, 4. Methods The EMBASE, PubMed, and Ovid (MEDLINE) databases were searched from establishment to February 28, 2022, according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Included studies had sex-based data on prevalence, outcomes, and complications of HA for FAIS. Reviews and commentaries were excluded. Data were combined, and between-sex differences were analyzed. Meta-analyses using random-effects models were performed when possible. Pooled risk ratios (RRs) and standardized mean differences were calculated. Results A total of 74 studies were included (213,059 patients; 132,973 female hips [62.4%] and 80,086 male hips [37.6%]). The mean age was 30.7 ± 7.7 years among male patients and 31.1 ± 7.8 years among female patients. Male patients experienced mixed-type impingement significantly more often (39.4% vs 27.2% for female patients; RR = 0.69 [95% confidence interval [CI], 0.58-0.81]; P < .001), whereas female patients experienced pincer-type impingement more often (50.6% vs 30.8% for male patients; RR = 2.35 [95% CI, 1.14-4.86]; P = .02). Male patients had higher likelihoods of undergoing femoroplasty (89.8% vs 77.4% for female patients; RR = 0.90 [95% CI, 0.83-0.97]; P = .006), acetabuloplasty (67.1% vs 59.3% for female patients; RR = 0.87 [95% CI, 0.79-0.97]; P = .01), or combined femoroplasty/acetabuloplasty (29.2% vs 14.5% for female patients; RR = 0.63 [95% CI, 0.44-0.90]; P = .01). Although female patients showed greater improvements in Hip Outcome Score-Sport-Specific subscale (P = .005), modified Harris Hip Score (P = .006), and visual analog scale pain (P < .001), both sexes surpassed the minimal clinically important difference at 1, 2, and 5 years postoperatively. Female patients had higher complication rates (P = .003), although no sex-based differences were found in total hip arthroplasty conversion rates (P = .21). Conclusion Male patients undergoing HA for FAIS had a higher prevalence of mixed-type FAIS while female patients had more pincer-type FAIS. Female patients gained greater improvements in PROs, although both sexes exceeded the minimal clinically important difference, suggesting that both male and female patients can benefit from HA.
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Affiliation(s)
- Madeline M. Owen
- Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Chetan Gohal
- Division of Orthopaedic Surgery, Northwestern University, Chicago, Illinois, USA
| | - Hunter S. Angileri
- Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Matthew J. Hartwell
- Division of Orthopaedic Surgery, Northwestern University, Chicago, Illinois, USA
| | - Mark A. Plantz
- Division of Orthopaedic Surgery, Northwestern University, Chicago, Illinois, USA
| | - Vehniah K. Tjong
- Division of Orthopaedic Surgery, Northwestern University, Chicago, Illinois, USA
| | - Michael A. Terry
- Division of Orthopaedic Surgery, Northwestern University, Chicago, Illinois, USA
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Robinson PG, Lu H, Williamson T, Maempel JF, Murray I, MacDonald DJ, Hamilton DF, Gaston P. Do the outcomes of hip arthroscopy for femoroacetabular impingement change over time? Orthop Traumatol Surg Res 2022; 108:103157. [PMID: 34856404 DOI: 10.1016/j.otsr.2021.103157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 11/05/2021] [Accepted: 11/23/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND The purpose of this study was to search for changes in functional outcomes of patients undergoing hip arthroscopy for femoroacetabular impingement (FAI) between short and medium-term follow-up. Secondary aims included reporting rates of revision surgery and total hip arthroplasty (THA) at medium-term follow-up. HYPOTHESIS We hypothesised that patients' functional outcomes would improve between short and medium-term follow-up. PATIENTS AND METHODS Consecutive patients undergoing hip arthroscopy with a diagnosis of femoroacetabular impingement with labral tears between February 2013 and June 2015 were included. Twelve item international hip outcome tool (iHOT-12) and EuroQol 5D-5L (EQ-5D) scores were collected preoperatively, at short-term and medium-term follow-up. Short-term scores were recorded at a minimum of one year postoperatively and medium-term scores at a minimum of five years postoperatively. Survivorship was assessed with Kaplan-Meier analysis. RESULTS Short-term outcome data (at median follow-up 1.6 year, Interquartile range [IQR] 1-2.5) was available for 70 of 87 patients (80.5%) and medium-term outcome data (at median follow-up of 6.5 years, IQR 6-7.1) was available for 68 patients (78.2%). Median age at the time of surgery was 31 years (IQR 25-37). The median iHOT-12 scores at short and medium-term follow-up were 72 (IQR 48.75-91.25) and 85.8 (IQR 66.7-96.7) respectively (p<0.001). Medium-term survivorship was 91.2%. Survivorship following labral repair was 94.2%, and 81.3% following labral debridement (p=0.09). DISCUSSION Patients undergoing hip arthroscopy for FAI reported continued improvement in iHOT-12 scores between short and medium-term follow-up. Medium-term survivorship following FAI surgery may be greater when the labrum is repaired, although comparisons are limited by their differing indications. Conversion to THA was low with just 4 patients (4.6%) undergoing or being listed for THA at final follow-up. LEVEL OF EVIDENCE IV, Case series.
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Affiliation(s)
| | - Helen Lu
- Edinburgh Medical School, The University of Edinburgh, Edinburgh, UK
| | - Tom Williamson
- Edinburgh Medical School, The University of Edinburgh, Edinburgh, UK
| | - Julian F Maempel
- Department of Trauma & Orthopaedics, Mater Dei Hospital, Msida, Malta
| | - Iain Murray
- Edinburgh Orthopaedics, Royal Infirmary of Edinburgh, Edinburgh, UK
| | | | - David F Hamilton
- Edinburgh Orthopaedics, Royal Infirmary of Edinburgh, Edinburgh, UK
| | - Paul Gaston
- Edinburgh Orthopaedics, Royal Infirmary of Edinburgh, Edinburgh, UK
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Dion MO, Simonyan D, Faure PA, Pelet S, May O, Bonin N, Carsen S, Beaulé P, Nault ML, Belzile EL. Validation of the French version of the Self-Administered International Hip Outcome Tool-12 Questionnaire and determination of the Minimal Clinically Important Difference (MCID) in the French speaking population. Orthop Traumatol Surg Res 2021; 107:103083. [PMID: 34601161 DOI: 10.1016/j.otsr.2021.103083] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/06/2021] [Accepted: 06/28/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND Patient-Reported Outcomes tools are becoming the gold standard in the evaluation of results in orthopaedic surgery. In 2012, the International Hip Outcome Tool-12 (iHOT-12) was developed. This self-administered questionnaire was designed to address the day-to-day clinical setting with faster completion and easier patient flow. In 2021, a French translation of the iHOT-33 questionnaire, from which the iHOT-12 is derived, proved to be valid. Since there is not data in French regarding iHOT-12, we performed a prospective study aiming to answer: (1) is this French version of the iHOT-12 questionnaire as valid, (2) can the minimal clinically important difference (MCID) value for patients undergoing hip arthroscopy for femoro-acetabular impingement (FAI) be defined? HYPOTHESIS It is hypothesized that the iHOT-12-Fr would be valid and responsive to change in a cohort treated for FAI. PATIENTS AND METHODS Using the COSMIN recommendations, a multicentric prospective cohort study was conducted to evaluate the reliability, validity, responsiveness and MCID of the iHOT-12-Fr. RESULTS In total, 101 patients were recruited for participation in the project. The reliability of the iHOT-12-Fr questionnaire was assessed with the intraclass correlation coefficient (ICC=0.84) and the internal consistency with a Cronbach's alpha (α=0.86). The standard error of measurement (SEM=6.7) and the smallest detectable change (SDC=1.8) were calculated. Construct validity was evaluated with Pearson's correlation coefficients (r) by comparing the iHOT-12-Fr with the iHOT-33-Fr (r=0.96), the Hip disability and Osteoarthritis Outcome Score-Fr (r=0.68) and Nonarthritic Hip Score-Fr (r=0.82). Responsiveness was shown with a standardized effect size of 1.18, standardized response mean of 0.73, responsiveness ratio of 1.4 and an MCID of 11 points. DISCUSSION Metrological qualities of the iHOT-12-Fr are comparable to the original version and other versions translated into different languages. This study proves that the French translation of the iHOT-12 is valid, reliable and compares to the original iHOT-12. LEVEL OF EVIDENCE IV prospective study.
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Affiliation(s)
- Marc-Olivier Dion
- Département de Chirurgie Orthopédique, CHU de Québec-Hôpital de l'Enfant-Jésus, 1401 18e Rue, Québec, Québec, G1J 1Z4, Canada.
| | - David Simonyan
- Centre de recherche clinique et évaluative, CHU de Québec, 2705 Boulevard Laurier, Québec, Québec, G1V 4G2, Canada
| | - Philippe-Alexandre Faure
- Département de Chirurgie Orthopédique, CHU de Québec-Hôpital de l'Enfant-Jésus, 1401 18e Rue, Québec, Québec, G1J 1Z4, Canada
| | - Stephane Pelet
- Département de Chirurgie Orthopédique, CHU de Québec-Hôpital de l'Enfant-Jésus, 1401 18e Rue, Québec, Québec, G1J 1Z4, Canada
| | - Olivier May
- Médipôle Garonne, clinique du sport, 45, rue de Gironis, 31036 Toulouse, France
| | - Nicolas Bonin
- Lyon Ortho Clinic, Lyon, 29B, avenue des sources, 69009 Lyon, France
| | - Sasha Carsen
- Département de Chirurgie Orthopédique, Centre Hospitalier pour enfants de l'est de l'Ontario, 401 Smyth Rd, Ottawa, Ontario, K1H 8L1, Canada
| | - Paul Beaulé
- Département de Chirurgie Orthopédique, L'Hôpital d'Ottawa, 1053, av. Carling, Ottawa, Ontario, K1Y 4E9, Canada
| | - Marie-Lyne Nault
- Département de Chirurgie, CHU Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, Québec, H3T 1C5, Canada
| | - Etienne L Belzile
- Département de Chirurgie Orthopédique, CHU de Québec-Hôpital de l'Enfant-Jésus, 1401 18e Rue, Québec, Québec, G1J 1Z4, Canada
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Robinson PG, Rankin CS, Murray IR, Maempel JF, Gaston P, Hamilton DF. The forgotten joint score-12 is a valid and responsive outcome tool for measuring success following hip arthroscopy for femoroacetabular impingement syndrome. Knee Surg Sports Traumatol Arthrosc 2021; 29:1378-1384. [PMID: 32691092 PMCID: PMC8038977 DOI: 10.1007/s00167-020-06138-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 06/26/2020] [Indexed: 11/13/2022]
Abstract
PURPOSE The forgotten joint score-12 (FJS-12) is an outcome questionnaire designed to evaluate joint awareness. The responsiveness and validity of the English language version of the FJS-12 in patients undergoing hip arthroscopy for femoroacetabular impingement (FAI) is not known. METHODS Consecutive patients undergoing hip arthroscopy for a diagnosis of FAI were prospectively followed up over a 1 year period. Patients completed preoperative and postoperative FJS-12, EuroQol 5 Dimension (EQ-5D-5L), and the 12-item international hip outcome tool (iHOT-12). We evaluated construct validity with Spearman correlation coefficients for the FJS-12, and responsiveness by way of effect size and ceiling effects. RESULTS Forty-six patients underwent hip arthroscopy, of which 42 (91%) completed post-operative PROMs at 1 year follow-up. Construct validity was strong with the iHOT-12 (r = 0.87) and also the EQ-5D-5L (r = 0.83). The median postoperative FJS score was 50.2 (IQR 64). The mean change in score for the FJS-12 was 31 points (SD 31) (p < 0.001), with an effect size (Cohen's d) of 1.16. Preoperatively, three patients scored the lowest possible value resulting in a floor effect of 7.1%. Similarly, only three patients (7.1%) scored the best possible score post-operatively. CONCLUSION This is the first evaluation of the joint awareness concept in the English language version of the FJS-12 following hip arthroscopy for FAI. The FJS-12 is a valid and responsive tool for the assessment of this cohort of patients. LEVEL OF EVIDENCE II.
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Affiliation(s)
- Patrick G. Robinson
- grid.4305.20000 0004 1936 7988Trauma and Orthopaedic Department, University of Edinburgh, 51 Little France Crescent, Edinburgh, EH16 4SA UK
| | - C. S. Rankin
- grid.4305.20000 0004 1936 7988Trauma and Orthopaedic Department, University of Edinburgh, 51 Little France Crescent, Edinburgh, EH16 4SA UK
| | - I. R. Murray
- grid.4305.20000 0004 1936 7988Trauma and Orthopaedic Department, University of Edinburgh, 51 Little France Crescent, Edinburgh, EH16 4SA UK
| | - J. F. Maempel
- grid.413249.90000 0004 0385 0051Department of Trauma and Orthopaedics, Royal Prince Alfred Hospital, Camperdown, NSW Australia
| | - P. Gaston
- grid.4305.20000 0004 1936 7988Trauma and Orthopaedic Department, University of Edinburgh, 51 Little France Crescent, Edinburgh, EH16 4SA UK
| | - D. F. Hamilton
- grid.4305.20000 0004 1936 7988Trauma and Orthopaedic Department, University of Edinburgh, 51 Little France Crescent, Edinburgh, EH16 4SA UK
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