Hips With Acetabular Retroversion Can Be Safely Treated With Advanced Arthroscopic Techniques Without Anteverting Periacetabular Osteotomy: Midterm Outcomes With Propensity-Matched Control Group

Editorial Commentary: Diagnosis of Hip Acetabular Retroversion Requires 3-Dimensional Imaging

Diagnosis of global hip acetabular retroversion requires 3-dimensional imaging. Using anteroposterior pelvis radiographs, the crossover sign has been associated with retroversion. Recent research reports that the ischial spine sign and posterior wall sign also should be considered, yet even taking into account all 3 signs, the false-positive rate for retroversion is reported as greater than 35%. In truth, an anteroposterior radiograph is not sufficient for determination of acetabular retroversion. Retroversion is a 3-dimensional condition, and magnetic resonance imaging or computed tomography-based measurements are required. Thus, before we can determine the efficacy of hip arthroscopy versus periacetabular osteotomy for patients with hip impingement secondary to acetabular retroversion, we need to precisely measure to confirm our diagnosis.

Global Acetabular Retroversion Is Not Associated With Differences in Outcomes After Primary Hip Arthroscopy Among Patients With Femoroacetabular Impingement Syndrome: A Matched Cohort Study With Minimum 5-Year Follow-Up

PURPOSE

To compare hip survivorship and patient-reported outcome measures (PROMs) after primary hip arthroscopy at 5-year follow-up between patients with femoroacetabular impingement syndrome (FAIS) with radiographic signs of global acetabular retroversion and those without.

METHODS

A retrospective matched-cohort study was conducted using a single-surgeon hip arthroscopy database. Patients were included if they underwent primary hip arthroscopy for treatment of FAIS, had preoperative hip x-rays, and had a minimum 5-year follow-up. Global retroversion was defined as the presence of ischial spine sign, posterior wall sign, and crossover sign on anteroposterior view. Patients with FAIS with global retroversion were matched 1:1 on age, sex, and body mass index to FAIS controls. The modified Harris Hip Score (mHHS) and Non-Arthritic Hip Score (NAHS) were administered preoperatively and at follow-up. Hip survivorship and PROMs were compared between the 2 groups using the paired t test, Wilcoxon signed rank test, and/or Cochran-Mantel-Haenszel test as appropriate. P values <.05 were considered significant.

RESULTS

Thirty-eight patients with global retroversion (mean age 40.6 ± 10.8 years, 60.5% female) were matched to 38 controls (mean age 41.3 ± 13.6 years, 60.5% female). Reoperation rates were the same in both groups (5.3%). On average, both groups reported significant pre- to postoperative improvement in mHHS (P < .001) and NAHS (P < .001), and there was no significant intergroup differences in the change in mHHS (P = .86) or NAHS (P = .90). Achievement rates for the patient acceptable symptom state on the mHHS were higher among males compared to females (P = .04) in both the global retroversion group (93.3% vs 73.9%) and the control group (93.3% vs 73.9%).

CONCLUSIONS

Patients with FAIS with and without global acetabular retroversion had no significant difference in outcomes after primary hip arthroscopy at a minimum 5-year minimum follow-up.

LEVEL OF EVIDENCE

Level III, retrospective comparative prognostic trial.

Intermediate-Term Outcomes of Hip Arthroscopy for Femoroacetabular Impingement Syndrome in Patients With Global Versus Isolated Lateral Acetabular Overcoverage

BACKGROUND

Previous studies evaluating the outcomes of hip arthroscopy for patients with global acetabular overcoverage and focal superolateral acetabular overcoverage suffer from short-term follow-up and inconsistent radiographic criteria when defining these subpopulations of patients with femoroacetabular impingement syndrome (FAIS).

PURPOSE

To evaluate the intermediate-term postoperative outcomes for patients with FAIS in the setting of global acetabular overcoverage, lateral acetabular overcoverage, and normal acetabular coverage.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients undergoing hip arthroscopy for FAIS were enrolled in a prospective cohort study, and those with a minimum follow-up of 5 years were included in this analysis. Patients were grouped based on type of acetabular coverage: global overcoverage (lateral center-edge angle [LCEA] ≥40°, with coxa profunda), lateral overcoverage (LCEA ≥40°, without coxa profunda), and no overcoverage (LCEA <40°). Functional outcomes (modified Harris Hip Score and Nonarthritic Hip Score) and failure of primary hip arthroscopy were compared between groups.

RESULTS

In total, 94 patients (mean age, 41.9 ± 14.2 years) were included with a mean follow-up duration of 6.1 ± 0.9 years. Of these patients, 40.4% had no acetabular overcoverage, 36.2% had lateral overcoverage, and 23.4% had global overcoverage. There was no difference between groups with respect to percentage of patients who underwent reoperation for either revision arthroscopy or conversion to total hip arthroplasty (28.9% for the normal acetabular coverage group, 29.4% for the lateral overcoverage group, and 31.8% for the global overcoverage group; P = .971). Among patients for whom primary hip arthroscopy did not fail, there was no difference in 5-year functional outcomes between groups. Postoperative LCEA >40° (β = -13.3; 95% CI, -24.1 to -2.6; P = .016), female sex (β = -14.5; 95% CI, -22.7 to -6.2; P = .001), and higher body mass index (β = -1.9; 95% CI, -2.8 to -1.0; P < .001) were associated with worse intermediate-term hip function in terms of modified Harris Hip Score.

CONCLUSION

There was no difference in functional outcomes or rate of reoperation at a minimum of 5 years postoperatively between those with global acetabular overcoverage, those with regional lateral overcoverage, and those with normal acetabular coverage. Provided that an appropriate acetabuloplasty is performed, there is no evidence to suggest that global acetabular overcoverage portends a worse prognosis than other FAIS subtypes.

Acetabular Rim Disorders: Epidemiology, Etiology, Management, and Outcomes

» Anatomic disorders of the acetabular rim are a common, correctable source of hip pain in younger patients.» Some common conditions of involving abnormal acetabular rim morphology include developmental dysplasia of the hip, pincer-type femoroacetabular impingement, acetabular protrusion, and acetabular retroversion.» Treatment option for these conditions were historically limited to open osteotomy and osteoplasty procedures; however, there is increasing use of arthroscopic intervention for these patients.» Arthroscopic intervention has demonstrated short-term success in a variety of focal acetabular rim disorders; however, further research is needed to determine the long-term outcomes of these procedures and their utility in more global pathology.

Outcomes of arthroscopy of the hip for femoroacetabular impingement based on intraoperative assessment using the Outerbridge classification

Aims

Hip arthroscopy (HA) has become the treatment of choice for femoroacetabular impingement (FAI). However, less favourable outcomes following arthroscopic surgery are expected in patients with severe chondral lesions. The aim of this study was to assess the outcomes of HA in patients with FAI and associated chondral lesions, classified according to the Outerbridge system.

Methods

A systematic search was performed on four databases. Studies which involved HA as the primary management of FAI and reported on chondral lesions as classified according to the Outerbridge classification were included. The study was registered on PROSPERO. Demographic data, patient-reported outcome measures (PROMs), complications, and rates of conversion to total hip arthroplasty (THA) were collected.

Results

A total of 24 studies were included with a total of 3,198 patients (3,233 hips). Patients had significantly less improvement in PROMs if they had Outerbridge grade III and IV lesions (p = 0.012). Compared with microfracture, autologous matrix-induced chondrogenesis (AMIC) resulted in significantly reduced rates of conversion to THA (p = 0.042) and of revision arthroscopy (p = 0.038). Chondral repair procedures in these patients also did not significantly reduce the rates of conversion to THA (p = 0.931), or of revision arthroscopy (p = 0.218). However, compared with microfracture, AMIC significantly reduced the rates of conversion to THA (p = 0.001) and of revision arthroscopy (p = 0.011) in these patients. Those with Outerbridge grade III and IV lesions also had significantly increased rates of conversion to THA (p = 0.029) and of revision arthroscopy (p = 0.023) if they had associated lesions of the acetabulum and femoral head. Those who underwent labral debridement had a significantly increased rate of conversion to THA compared with those who underwent labral repair (p = 0.015).

Conclusion

There is universal improvement in PROMs following HA in patients with FAI and associated chondral lesions. However, those with Outerbridge grade III and IV lesions had significantly less improvement in PROMs and a significantly increased rate of conversion to THA than those with Outerbridge grade I and II. This suggests that the outcome of HA in patients with FAI and severe articular cartilage damage may not be favourable.

Primary Hip Arthroscopy for Femoroacetabular Impingement Syndrome in Adolescents Improves Outcomes and Clinical Benefit Achievement Rates at Short-Term Follow-Up. A Multicenter Analysis

PURPOSE

To report minimum 2-year follow-up patient-reported outcome scores (PROs) and rates of achieving the minimal clinically important difference (MCID), the patient-acceptable symptomatic state (PASS), and the maximal outcome improvement (MOI) on adolescents following primary hip arthroscopy for femoroacetabular impingement syndrome (FAIS). Second, to determine risk factors for revision surgery.

METHODS

Prospectively collected data from two high-volume hip arthroscopy centers were retrospectively reviewed on adolescents (≤19 years old) who underwent primary hip arthroscopy between November 2008 and February 2019. Adolescents with a minimum 2-year follow-up for the modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), Hip Outcome Score-Sports Specific Subscale (HOS-SSS), International Hip Outcome Tool-12 (iHOT-12), and visual analog scale (VAS) for pain were included regardless of their growth plate status. Exclusion criteria were Tönnis grade >1, lateral center edge-angle <18°, and previous ipsilateral hip surgery or conditions. Preoperative and postoperative radiographic data, MCID, PASS, MOI, secondary surgeries, and complications were reported. A multivariable survival analysis for risk factors for secondary surgery was conducted.

RESULTS

A total of 287 hips (249 patients) were included (74.9% females). The mean values for age, body mass index, and follow-up were 16.3 ± 1.3 years, 22.3 ± 3.5, and 26.6 ± 9.4 months, respectively. Further, 88.9% underwent labral repair, 81.5% femoroplasty, and 85.4% capsular closure. Improvement for all PROs was reported (P < .001) with high patient satisfaction (8.8 ± 1.5). Achievement for the MCID was 71.7%, 83.0%, 68.1%, and 79.5% for the mHHS, NAHS, HOS-SSS, and iHOT-12, respectively. Achievement for the PASS was 68.3% for the mHHS and 73.2% for the NAHS. The MOI for mHHS, NAHS, and VAS was 58.3%, 77.0%, and 59.6%, respectively. Rates of revision hip arthroscopy, cam recurrence, and heterotopic ossification were 5.8%, 1.7%, and 5.5%, respectively. Acetabular retroversion was found to be a risk factor for revision surgery (P = .03).

CONCLUSION

The results of this multi-center study demonstrated that adolescents who underwent primary hip arthroscopy for FAIS reported significant improvement in all PROs, with satisfactory achievement rates for the MCID, PASS, MOI, and high patient satisfaction at a minimum 2-year follow-up.

LEVEL OF EVIDENCE

IV, retrospective multicenter study.

Acetabular retroversion does not affect outcome in primary hip arthroscopy for femoroacetabular impingement

PURPOSE

The surgical treatment of femoral-acetabular impingement syndrome (FAIS) in patients with acetabular retroversion (AR) is arthroscopical or by a reverse periacetabular osteotomy (PAO). The purpose of the present study was to investigate the results after arthroscopic treatment of FAIS in patients with and without radiographic signs of AR in a large, prospective cohort from the Danish Hip Arthroscopy Registry (DHAR). The hypothesis was there is no difference in clinical outcome between the two groups.

METHODS

Data on 4914 hip arthroscopies performed during 2012-2019 were obtained from DHAR. Patients with radiographic signs of osteoarthritis (Tönnis > 1), hip dysplasia (CEA < 25°), other hip pathologies or previous hip surgery were excluded. The clinical outcomes for patients with AR [defined by a positive posterior wall sign (PWS) in combination with a positive Ischial Spine Sign (ISS)] and patients without AR (no PWS, no ISS) were analyzed 1 and 2 years after surgery. The primary outcomes were the six domains of the Copenhagen Hip and Groin Outcome score (HAGOS), while secondary outcomes were the Hip Sports Activity Scale (HSAS), a visual analogue pain scale (VAS) and a numeric rating scale (NRS) for pain.

RESULTS

A total of 3135 hip arthroscopies were included, of which 339 had AR, 1876 did not, and 920 presented one of the two signs (PWS and ISS). There were no statistically significant differences 1 and 2 years after surgery (n.s.) between patients with and without AR in HAGOS domain scores, HSAS, VAS, or NRS. Both groups showed improvement at both follow-ups. The two groups did not differ in relation to intraoperative findings and the procedures they have had.

CONCLUSION

The outcome 1 and 2 years after arthroscopic treatment of FAIS is not different for patients with and without AR.

LEVEL OF EVIDENCE

III.

Evaluation of additional causes of hip pain in patients with femoroacetabular impingement syndrome

Femoroacetabular impingement syndrome (FAIS) is an increasingly prevalent pathology in young and active patients, that has contributing factors from both abnormal hip morphology as well as abnormal hip motion. Disease progression can be detrimental to patient quality of life in the short term, from limitations on sport and activity, as well as the long term through early onset of hip arthritis. However, several concurrent or contributing pathologies may exist that exacerbate hip pain and are not addressed by arthroscopic intervention of cam and pincer morphologies. Lumbopelvic stiffness, for instance, places increased stress on the hip to achieve necessary flexion. Pathology at the pubic symphysis and sacroiliac joint may exist concurrently to FAIS through aberrant muscle forces. Additionally, both femoral and acetabular retro- or anteversion may contribute to impingement not associated with traditional cam/pincer lesions. Finally, microinstability of the hip from either osseous or capsuloligamentous pathology is increasingly being recognized as a source of hip pain. The present review investigates the pathophysiology and evaluation of alternate causes of hip pain in FAIS that must be evaluated to optimize patient outcomes.

Male Gender and Competitive Athlete Status Are Associated With Better Outcomes Following Hip Arthroscopy In Patients With Global Acetabular Retroversion

Purpose

To evaluate outcomes of hip arthroscopy in patients with global acetabular retroversion and to identify correlations between sex, radiographic measurements, athlete status, and return to play with patient-reported outcomes (PROs).

Methods

Retrospective study of patients with global acetabular retroversion who underwent arthroscopic femoroacetabular impingement (FAI) surgery was performed. Global acetabular retroversion was defined by 3 criteria: the crossover sign, ischial spine sign, and posterior wall sign on an anteroposterior (AP) pelvic radiograph. Radiographs were used to measure lateral center edge angle, alpha angle, and anterior and posterior wall indices. Femoral version was measured with 3-dimensional computed tomography. Demographics included age, gender, athlete status, return to play, and reoperation. PROs included modified Harris Hip Score, Hip Outcome Score (HOS), Hip Disability and Osteoarthritis Outcome Score, visual analog scale (VAS), and Veterans RAND-12. Spearman correlation determined correlation with perioperative PROs. Generalized estimating equation determined independent predictors. Significance was set at P = .05.

Results

From 2013 to 2019, 149 patients (65.0% female) with 160 hips with FAI and global acetabular retroversion underwent hip arthroscopy. Follow-up averaged 29.6 months. All PROs demonstrated significant improvement with the exception of the Veterans RAND-12 Mental. Female patients scored significantly lower on most postoperative PROs and had greater VAS scores (P = .0002-0.0402). A greater proportion of male subjects met the minimum clinically important difference for the modified Harris Hip Score (88.00% vs 78.79%) Low femoral version correlated with greater HOS ADL, HOS Sport, and Hip Disability and Osteoarthritis Outcome Score Sport scores (P = .0077-0.0177). Athletes reported lower preoperative VAS scores, and higher perioperative scores in multiple PROs (P = .0004-0.0486). Nine hips (5.63%) underwent reoperation.

Conclusions

Patients with global acetabular retroversion and FAI undergoing hip arthroscopy report good outcomes at short-term follow-up. Male subjects and athletes had superior outcomes compared to female subjects and nonathletes. Radiographic measurements did not correlate with outcomes with exception of low femoral version. Athletes reported lower preoperative pain scores and greater postoperative PROs than nonathletes.

Level of Evidence

Level IV, therapeutic case series.

Outcomes for the Arthroscopic Treatment of Femoroacetabular Impingement Syndrome With Acetabular Retroversion: A 3D Computed Tomography Analysis

BACKGROUND

Increased attention has been directed toward the acetabular morphology in the management of patients with femoroacetabular impingement syndrome (FAIS). Whether acetabular version influences patient-reported outcomes remains poorly understood.

PURPOSE

To use computed tomography (CT)-based 3-dimensional (3D) bone models to (1) quantify acetabular version in patients with FAIS, (2) compare acetabular version on 3D bone models with current plain radiographic parameters, and (3) explore the relationship between the magnitude of acetabular version and minimum 2-year clinical outcomes after hip arthroscopy.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Three-dimensional models of the pelvis and femur were generated by semiautomated segmentation and aligned to a standard coordinate system. Acetabular version was quantified at the 3-o'clock position, and 3 groups were identified: acetabular retroversion (AR; <15°), normal acetabular version (NV; 15°-25°), and acetabular anteversion (AA; >25°). Patient demographic characteristics, plain radiographic parameters, and clinical outcomes were analyzed, including the Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sports Subscale, modified Harris Hip Score (mHHS), International Hip Outcome Tool (iHOT-12), and visual analog scale (VAS) for pain and satisfaction.

RESULTS

Preoperative CT scans were acquired in 105 consecutive patients before hip arthroscopy for FAIS, of which 84 (80.0%) completed minimum 2-year patient-reported outcomes. The mean ± SD age and body mass index of patients were 33.9 ± 12.6 years and 26.0 ± 5.4, respectively; 70.2% were female. The number of patients and the mean central acetabular version within each group were as follows: AR (n = 12; 11.3°± 2.7°), NV (n = 56; 20.7°± 2.9°), and AA (n = 16; 28.5°± 2.7°). Posterior wall sign was the only plain radiographic parameter that was significantly more observed in the AR group than in the other 2 groups. At minimum 2-year follow-up, significant between-group differences in the mHHS, iHOT-12, and VAS for pain and satisfaction (P < .05) were appreciated, while post hoc analysis with Bonferroni correction (P < .0167) found lower scores on the mHHS, iHOT-12, and VAS for pain and satisfaction in patients with AR as compared with NV. Lower scores on the VAS for satisfaction were reported in patients with AR when compared with AA (P = .006) but not on the mHHS (P = .023), iHOT-12 (P = .032), or VAS for pain (P = .072).

CONCLUSION

Traditional plain radiographic indices to describe AR, including crossover sign and ischial spine sign, were not reliable in defining AR according to 3D models derived from CT scans. Only the posterior wall sign was observed in a higher proportion in the AR group. Patients with AR demonstrated inferior outcomes when compared with patients with NV and AA after hip arthroscopy for FAIS.

The Effect of Femoral and Acetabular Version on Outcomes Following Hip Arthroscopy: A Systematic Review

BACKGROUND

Torsional hip deformities are common among patients undergoing hip arthroscopy. However, recent studies have suggested conflicting outcomes following arthroscopy in the setting of abnormal hip version. The purpose of this study was to systematically evaluate the literature and determine the impact of femoral and acetabular version on patient-reported outcomes following primary arthroscopic hip surgery.

METHODS

This study was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. Studies investigating femoral and acetabular version in primary hip arthroscopy with clinical outcomes were identified, and data were extracted in duplicate.

RESULTS

Overall, 11 studies met inclusion criteria and comprised 1,297 hips (726 femora and 571 acetabulae), with a mean patient age of 29.2 years (range, 14 to 74.7 years). In patients with acetabular retroversion, there was no significant difference, when compared with the normal acetabular version group, in the modified Harris hip score (mHHS), the Hip Outcome Score-Sports Specific Subscale (HOS-SSS), and visual analog scale (VAS) pain scores postoperatively. Among patients with femoral retroversion, in 2 of 3 studies, the authors reported no difference in mHHS postoperatively compared with patients with normal femoral version. In patients with high femoral anteversion, in 2 of 3 studies, the authors reported a significant difference in postoperative mHHS favoring patients with normal femoral version. Studies examining high femoral anteversion included patients with borderline hip dysplasia and patients who underwent concurrent psoas-lengthening procedures.

CONCLUSIONS

Although the definition of the normal version of the hip varied within the literature, hip arthroscopy in patients with acetabular retroversion resulted in no difference in functional outcomes compared with patients with normal version. Postoperative functional outcomes in patients with femoral retroversion and high femoral anteversion were mixed, although the procedure was possibly less effective in high femoral anteversion combined with specific clinical scenarios. Further prospective studies based on standardized definitions and version analysis techniques would be useful in identifying the precise surgical indications for safe arthroscopic surgical procedures in patients with version abnormalities of the femur and acetabulum, particularly those with high femoral anteversion and retroversion.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Best Practice Guidelines for Propensity Score Methods in Medical Research: Consideration on Theory, Implementation, and Reporting. A Review

Rigorous and reproducible methodology of controlling for bias is essential for high-quality, evidence-based studies. Propensity score matching (PSM) is a valuable way to control for bias and achieve pseudo-randomization in retrospective observation studies. The purpose of this review is to 1) provide a clear conceptual framework for PSM, 2) recommend how to best report its use in studies, and 3) offer some practical examples of implementation. First, this article covers the concepts behind PSM, discusses its pros and cons, and compares it with other methods of controlling for bias, namely, hard/exact matching and regression analysis. Second, recommendations are given for what to report in a manuscript when PSM is used. Finally, a worked example is provided, which can also serve as a template for the reader's own studies. A study's conclusions are only as strong as its methods. PSM is an invaluable tool for producing rigorous and reproducible results in observational studies. The goal of this article is to give practicing clinical physicians not only a better understanding of PSM and its implications but the ability to implement it for their own studies. STUDY DESIGN: Review.

Lower pelvic tilt, lower pelvic incidence, and increased external rotation of the iliac wing in patients with femoroacetabular impingement due to acetabular retroversion compared to hip dysplasia

AIMS

The effect of pelvic tilt (PT) and sagittal balance in hips with pincer-type femoroacetabular impingement (FAI) with acetabular retroversion (AR) is controversial. It is unclear if patients with AR have a rotational abnormality of the iliac wing. Therefore, we asked: are parameters for sagittal balance, and is rotation of the iliac wing, different in patients with AR compared to a control group?; and is there a correlation between iliac rotation and acetabular version?

METHODS

A retrospective, review board-approved, controlled study was performed including 120 hips in 86 consecutive patients with symptomatic FAI or hip dysplasia. Pelvic CT scans were reviewed to calculate parameters for sagittal balance (pelvic incidence (PI), PT, and sacral slope), anterior pelvic plane angle, pelvic inclination, and external rotation of the iliac wing and were compared to a control group (48 hips). The 120 hips were allocated to the following groups: AR (41 hips), hip dysplasia (47 hips) and cam FAI with normal acetabular morphology (32 hips). Subgroups of total AR (15 hips) and high acetabular anteversion (20 hips) were analyzed. Statistical analysis was performed using analysis of variance with Bonferroni correction.

RESULTS

PI and PT were significantly decreased comparing AR (PI 42° (SD 10°), PT 4° (SD 5°)) with dysplastic hips (PI 55° (SD 12°), PT 10° (SD 6°)) and with the control group (PI 51° (SD 9°) and PT 13° (SD 7°)) (p < 0.001). External rotation of the iliac wing was significantly increased comparing AR (29° (SD 4°)) with dysplastic hips (20°(SD 5°)) and with the control group (25° (SD 5°)) (p < 0.001). Correlation between external rotation of the iliac wing and acetabular version was significant and strong (r = 0.81; p < 0.001). Correlation between PT and acetabular version was significant and moderate (r = 0.58; p < 0.001).

CONCLUSION

These findings could contribute to a better understanding of hip pain in a sitting position and extra-articular subspine FAI of patients with AR. These patients have increased iliac external rotation, a rotational abnormality of the iliac wing. This has implications for surgical therapy with hip arthroscopy and acetabular rim trimming or anteverting periacetabular osteotomy (PAO). Cite this article: Bone Jt Open 2021;2(10):813-824.

Hip Arthroscopy for Femoroacetabular Impingement: Minimal Clinically Important Difference Rates Decline From 1- to 5-Year Outcomes

Purpose

To correlate patient-reported outcomes (PROs) and minimal clinically important difference (MCID) achievement rates after hip arthroscopy for femoroacetabular impingement syndrome (FAI).

Methods

Patients with clinically diagnosed FAI who underwent primary hip arthroscopy from September 2012 to March 2014 with a minimum of 5-year outcomes were identified. Patients undergoing labral debridement, microfracture, bilateral procedures, with evidence of dysplasia, Tönnis grade >1, and joint space <2 mm were excluded. Analysis of variance was used to compare PROs. Survival rates were determined using Kaplan–Meier analysis. Regression analysis identified associations with modified Harris Hip Scores (mHHS), minimal clinically important difference (MCID) rates, and Nonarthritic Hip Scores (NAHS).

Results

A total of 85 of 101 eligible consecutive patients (84% inclusion) (age: 41.4 ± 14.0 years; 69% female, mean body mass index [BMI] 25.0 ± 4.2) met inclusion and exclusion criteria. Patients underwent labral repair (100%) and a combination of cam (86%) and pincer resection (99%). The 5-year survival-to-revision rate was 77% whereas 5-year survival rate to total hip arthroplasty was 94%. The 1-year (87.4 ± 13.6) and 5-year (84.5 ± 13.5) mHHS scores were greater versus preoperative scores (46.3 ± 11.3, P < .001). There was a decrease in MCID rate between 1-year (n = 74, 87%) and 5-year (n = 61, 73%, P = .019) outcomes. The 1-year (87.4 ± 12.7) and 5-year (89.2 ± 15.8) NAHS scores were greater versus preoperative scores (49.7 ± 12.7, P < .001). Regression demonstrated associations between BMI (MCID: P = .033; NAHS: P = .010), age (mHHS: P = .031), and cam resection (mHHS: P = .010) with 5-year outcomes.

Conclusions

There is a decline in MCID at 5-year follow-up after hip arthroscopy for FAI. Lower BMI, younger age, and cam resection are associated with positive outcomes. There is excellent index procedure survivability and excellent total hip arthroplasty prevention rate.

Level of Evidence

Level IV.

Mid- to Long-Term Outcomes of Hip Arthroscopy: A Systematic Review

PURPOSE

To assess mid- to long-term patient-reported outcomes (PROs) of hip arthroscopy as well as the rates of secondary surgery and to identify indications for surgery and noted predictors of failure.

METHODS

A systematic review of the current literature was performed with the terms "hip arthroscopy," "outcomes," "patient-reported outcomes," "mid-term," "5-year," "long-term," and "10-year" in the PubMed, Cochrane, and Embase databases in April of 2020 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Data for study characteristics, patient demographics, follow-up time, indications for surgery, PROs, predictors of failure or unfavorable PROs, and rates of secondary hip preservation surgery and conversion to total hip arthroplasty were collected.

RESULTS

Thirteen articles were included. Four studies were level III and 9 were level IV. In total, 1571 hips were included, and the average follow-up time ranged from 60 to 240 months. The most common indications for hip arthroscopy were labral tears and femoroacetabular impingement syndrome. Twelve studies reported on PROs and all reported improvement at latest follow-up. The most reported on scores were the modified Harris Hip Score, Harris Hip Score, and the Hip Outcome Score-Sport Specific Subscale. When grouped based on average follow-up time, the conversion rates at the 5- and 10-year time points ranged from 3.0% to 17.9% and 2.4% to 32.5%, respectively. One study with 20-year follow-up reported a conversion rate of 41.0%. Osteoarthritis and increased age were the most cited predictors for secondary surgery or decreased PROs.

CONCLUSIONS

At mid- to long-term follow-up, patients who underwent primary hip arthroscopy demonstrated improvement in several PROs. There was great variability in rates for revision surgery and conversion to total hip arthroplasty. The most common indications for hip arthroscopy were labral tears and femoroacetabular impingement syndrome. Osteoarthritis and increased age were the most cited predictors for unfavorable outcomes.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III and IV studies.