The statistical fragility of randomized controlled trials comparing hip arthroscopy to conservative management for the treatment of femoroacetabular impingement syndrome

BackgroundThe fragility index (FI) assesses the robustness or fragility of statistically significant results in randomized controlled trials (RCTs), but is limited to dichotomous outcomes. The continuous fragility index (CFI) extends this concept to continuous outcomes. This is particularly relevant when comparing hip arthroscopy (HA) and conservative management or physical therapy (PT) for the treatment of femoroacetabular impingement syndrome (FAIS).PurposeTo identify RCTs comparing outcomes after HA or conservative management for FAIS and characterize the fragility of statistically significant results.MethodsPubMed, Embase, Cochrane, and ClinicalTrials.gov were utilized for RCT search. The Cochrane risk-of-bias tool for randomized trials was used to assess the risk of bias. RCTs were included if (1) they contained both a HA and conservative management or PT arm and (2) reported at least one statistically significant outcome. CFI was calculated for significant continuous outcomes. FI was calculated for significant categorical outcomes. The fragility quotient (FQ) was calculated.ResultsFive RCTs met inclusion criteria. Risk of bias was “low” in 2 RCTs and “some concerns” in 3 RCTs. The mean CFI was 15.84 (range, 8.8-28.4); median CFI was 13. The mean and median dichotomous FI was 3.5 (range, 1-6). Loss to follow-up exceeded calculated CFI or FI in 2 of the 5 RCTs.ConclusionsRCTs comparing patient-reported outcomes (PROs) and achievement of clinically significant outcomes (CSOs) between HA versus PT for the treatment of FAIS demonstrated a high CFI and FI, indicating robust results, or more robust than other RCTs in the sports medicine literature.Level of evidenceMeta-Analysis; Level of Evidence, 2

ABSTRACTSeveral meta‐analyses of surgical versus non‐operative treatment of femoroacetabular impingement syndrome (FAIS) have been published, but reliable evidence is still lacking. The aim of this meta‐analysis of randomized controlled trials (RCTs) was to assess the outcomes of FAIS patients treated conservatively compared with those treated with hip arthroscopy (HAS). PubMed, CENTRAL of the Cochrane Library, Epistemonikos, and Embase databases were searched up to March 31, 2025. Quality was assessed using the Cochrane Risk of Bias 2 tool, the level of evidence for each outcome parameter was determined using the GRADE system, and publication bias was presented in funnel plots. In a common effect and random effects meta‐analysis, mean differences (MDs) between the conservative treatment group and the HAS group were calculated with 95% confidence intervals (CIs) using the Hartung‐Knapp‐Sidik‐Jonkman heterogeneity estimator. A total of 7 RCTs with a total of 489 patients in the conservative treatment group and 484 patients in the HAS group met the inclusion criteria. Of the 7 RCTs included, four were assessed as having a low risk of bias, one as having a moderate risk of bias, and two as having a high risk of bias. The outcomes “post‐intervention functional MCID” and “iHOT at ≤ 12 months post‐intervention” had a high level of evidence, and the outcome “HOS‐ADL at ≤ 8 months post‐intervention” had a moderate level of evidence. No significant publication bias was detected for any outcome. The HAS group had a statistically significant 0.85 higher post‐intervention functional MCID (common effect model: MD: 0.85 CIs 0.53–1.17; random effects model: MD: 0.85 CIs 0.64–1.06; I2 = 0%; τ2 = 0.02; p = 0.96) and a statistically significant 10.74 higher iHOT at ≤ 12 months post‐intervention than the conservative treatment group (common effect model: MD: 10.74 CIs 7.06 to 14.42; random effects model: MD: 10.98 CIs 6.62 to 15.34; I2 = 0%; τ2 = 7.52; p = 0.62). There was no difference between the HAS group and the conservative treatment group in HOS‐ADL at ≤ 8 months post‐intervention (common effect model: MD: 5.62 CIs 1.76 to 9.48; random effects model: MD: 4.10 CIs −12.31 to 20.50; I2 = 69%; τ2 = 29.88; p = 0.04). This meta‐analysis using high‐quality statistical methods showed a statistically significant higher post‐intervention functional MCID and iHOT at ≤ 12 months post‐intervention in favor of the HAS group compared to the conservative treatment group. HOS‐ADL at ≤ 8 months post‐intervention showed no differences.

Regarding “Operative Versus Nonoperative Treatment of Femoroacetabular Impingement Syndrome: A Meta-analysis of Short-Term Outcomes”

To appraise the highest available evidence provided by randomized controlled trials (RCTs) on the effectiveness of hip arthroscopy versus physical therapy in patients with femoroacetabular impingement syndrome (FAIS). Four databases (Medline, Embase, Web of Science, and Scopus) were systematically searched until October 1, 2019. Eligible studies were RCTs in which patients with FAIS underwent hip arthroscopy or physical therapy. The study outcome was the International Hip Outcome Tool, 33 Items (iHOT-33) score, a measure of hip pain, function, and quality of life, assessed at baseline and at the follow-up closer to 12 months after randomization. The pooled mean difference in iHOT-33 scores within and between the treatment arms was computed using a random effects model. The minimum clinically important difference in the iHOT-33 scores was set at 10 points. Three RCTs evaluating iHOT-33 scores between 6 and 8 months after the interventions were included. Significant increases in iHOT-33 scores were observed from baseline to follow-up for both hip arthroscopy (22.3 points [95% confidence interval (95% CI) 17.3-27.4]) and physical therapy (13.0 points [95% CI 9.5-16.4]). Hip arthroscopy demonstrated significantly higher iHOT-33 scores at follow-up compared with physical therapy (10.9 points [95% CI 4.7-17.0]). Both hip arthroscopy and physical therapy resulted in statistically and clinically significant short-term improvements in hip pain, function, and quality of life in patients with FAIS. Hip arthroscopy was statistically superior to physical therapy in improving the outcome at follow-up even if improvement may not be detected by patients.

Operative Versus Nonoperative Treatment of Femoroacetabular Impingement Syndrome: A Meta-analysis of Short-Term Outcomes

Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial

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Author Reply to “Regarding ‘Routine Interportal Capsular Repair Does Not Lead to Superior Clinical Outcome Following Arthroscopic Femoroacetabular Impingement Correction With Labral Repair’”

Decreased Hip Labral Width Measured on Preoperative Magnetic Resonance Imaging Is Associated With Greater Revision Rate After Primary Arthroscopic Labral Repair for Femoroacetabular Impingement Syndrome at 5-Year Follow-Up

ObjectiveTo determine the effectiveness of hip arthroscopy combined with endoscopic iliotibial band (ITB) release in patients with both femoroacetabular impingement (FAI) syndrome and external snapping hip (ESH).MethodsRetrospectively review the preoperative and minimum of 2‐year follow‐up data of patients with both FAI syndrome and ESH who underwent endoscopic ITB release during hip arthroscopy (FAI + ESH group) from January 2014 to December 2018. The same number of age‐ and gender‐matched FAI syndrome patients without ESH undergoing hip arthroscopy were enrolled in the control group (FAI group). Patient‐reported outcomes (PROs) including international Hip Outcome Tool (iHOT‐33), modified Harris Hip Score (mHHS), visual analog scale for pain (VAS‐pain), and abductive force of affected hip at 3 month and 2 years postoperatively were comparatively analyzed. The VAS‐satisfaction score of two groups at 2 years postoperatively were also analyzed.ResultsThe prevalence of ESH in FAI syndrome patients undergoing hip arthroscopy in our institution was 5.5% (39 of 715 hips), including nine males (10 hips) and 29 females (29 hips). The mean age at the time of surgery was 32.1 ± 6.9 years (range, 22–48 years). According to inclusion and exclusion criteria, 23 patients were enrolled in FAI + ITB group. Twenty‐three age‐ and sex‐matched FAI syndrome patients were enrolled in FAI group. At 24 months postoperatively, no patient still suffered ESH symptoms and painful palpation at lateral region in FAI + ITB group. The iHOT‐33, mHHS, and VAS‐pain score of patients in FAI + ESH group were significantly severer than patients in FAI group preoperatively (41.6 ± 7.5 vs 48.8 ± 7.2, 54.8 ± 7.2 vs 59.2 ± 6.9, 5.5 ± 0.9 vs 4.7 ± 1.0; P < 0.05), while there was no significant difference in these scores between the patients in FAI + ESH group and FAI group at 3‐month and 24‐month follow‐up (73.6 ± 8.5 vs 76.1 ± 6.9, 85.3 ± 7.8 vs 84.2 ± 6.6, 0.8 ± 0.9 vs 0.6 ± 0.9; P > 0.05). At 3 months after surgery, the abductive force of operated hip was significantly smaller than that in FAI group (82.4 ± 12.4 N vs 91.9 ± 16.1 N, P < 0.05), whereas there was no significant difference at 24 months after surgery (101.6 ± 14.9 N vs 106.5 ± 13.7 N, P > 0.05). The VAS‐satisfaction scores of patients in the two groups were at a similarly high level (90.5 ± 6.8 vs 88.8 ± 7.3, P > 0.05). There was no complication and no arthroscopic revision in either group until 2‐year follow‐up.ConclusionAlthough abductive force recovery of the hip was delayed, hip arthroscopy combined with endoscopic ITB release addressed hip snapping in patients with both FAI syndrome and ESH, and could get similar functional improvement, pain relief, recovery speed, as well as patient satisfaction compared with the pure hip arthroscopy in FAI syndrome patients without ESH.

Background: Patients with femoroacetabular impingement syndrome (FAIS) may frequently have co-existing sacroiliac joint (SIJ) pain. It is known that patients with lower back pain undergoing total hip arthroplasty (THA) have inferior outcomes; however, it is unclear what the effect of SIJ pain is on outcomes after hip arthroscopy. Purpose: To determine whether patients undergoing hip arthroscopy with SIJ pain either subjectively or on physical examination achieve similar postoperative improvement in patient-reported outcomes (PROs) compared with patients without SIJ pain at 2-year follow-up. Study Design: Cohort study; Level of evidence, 3. Methods: Patients with a minimum 2-year follow-up who underwent primary hip arthroscopy for FAIS with SIJ pain were matched in a 1:2 ratio to controls without SIJ pain. Baseline demographics, as well as postoperative PROs and rates of achievement of the minimal clinically important difference (MCID) or Patient Acceptable Symptom State (PASS) at 2-year follow-up were compared between the 2 groups. Results: A total of 73 patients (75 hips) with SIJ pain were matched to 150 control patients (150 hips) without SIJ pain. Both groups demonstrated statistically significant improvement in all PROs at 2 years (P < .05 for all). Patients with SIJ pain had significantly lower postoperative PRO scores for the Hip Outcome Score–Activities of Daily Living (HOS-ADL) (SIJ pain: 80.4 ± 22.4 vs no SIJ pain: 88.0 ± 15.1; P = .006), modified Harris Hip Score (mHHS) (SIJ pain: 73.2 ± 22.8 vs no SIJ pain: 80.0 ± 17.3; P < .001), and International Hip Outcome Tool–12 questionnaire (iHOT-12) (SIJ pain: 61.7 ± 25.9 vs no SIJ pain: 73.7 ± 23.7; P = .008). There were no statistically significant differences in improvement (delta) in PRO scores between the 2 groups (P > .05 for all). The SIJ pain group had significantly lower achievement of MCID for the HOS-ADL (SIJ pain: 65.2% vs no SIJ pain: 80.5%; P = .044) but not HOS-SS, mHHS, or iHOT-12 (P > .05 for all). The SIJ pain group had significantly lower achievement of PASS for the mHHS (SIJ pain: 27.5% vs no SIJ pain: 45.3%; P = .030) and iHOT-12 (SIJ pain: 31.0% vs no SIJ pain: 56.0%; P = .010) but not the HOS-ADL and HOS-SS (P > .05 for both). Only 4.1% of patients with SIJ pain and 2.4% of controls required revision surgery or converted to THA at the time of final follow-up (P = .69). Conclusion: Patients with FAIS and SIJ pain on history or physical examination experience significant improvement in PROs at 2 years after hip arthroscopy. However, they may be less likely to achieve the MCID or PASS and have significantly lower postoperative PROs compared with a matched cohort of patients without SIJ pain. Overall rates of revision and conversion to THA were similarly low in both groups.

Background: Hip arthroscopy has become the mainstay surgical intervention for the treatment of femoroacetabular impingement syndrome (FAIS). However, postoperative outcomes and rates of secondary surgery are mixed in patients with differing levels of preoperative osteoarthritis (OA). Furthermore, there is a paucity of literature comparing patients with and without OA at long-term follow-up. Purpose: To compare outcomes and rates of secondary surgery at minimum 10-year follow-up, including revision hip arthroscopy and conversion to total hip arthroplasty (THA), in patients with Tönnis grade 1 undergoing hip arthroscopy for FAIS compared with a propensity-matched control group of patients with Tönnis grade 0. Study Design: Cohort study; Level of evidence, 3. Methods: Patients who underwent primary hip arthroscopy for FAIS between January 2012 and February 2013 were identified. Patients with Tönnis grade 1 were propensity matched in a 1:2 ratio by age, sex, and body mass index (BMI) to patients with Tönnis grade 0. Patient-reported outcomes (PROs) were collected at varying timepoints including preoperatively and 1, 2, 5, and 10 years postoperatively and compared between the 2 cohorts. Rates of minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) achievement at 10 years were evaluated and compared between groups. Rates of secondary surgery including revision hip arthroscopy and conversion to total hip arthroplasty (THA) were evaluated. Gross survivorship between cohorts was evaluated using a Kaplan-Meier gross survivorship curve. A subanalysis was performed comparing patients with Tönnis grade 1 who converted to THA and those who did not. Results: A total of 31 patients with Tönnis grade 1 (age, 42.6 ± 9.0 years; BMI, 28.0 ± 6.3) were successfully matched to 62 patients with Tönnis grade 0 (age, 42.1 ± 8.5, P = .805; BMI, 26.1 ± 3.9, P = .117). Both the Tönnis grade 1 and Tönnis grade 0 groups demonstrated significant improvements regarding all PROs at minimum 10 years (P < .05 for all), except for the Hip Outcome Score Activities of Daily Living subscale (HOS-ADL) (P = .066) in the Tönnis grade 1 cohort. No significant difference (P > .05 for all) was noted between cohorts regarding any 10-year PRO. When the authors evaluated comparisons between preoperative and 1-, 2-, 5-, and 10-year PRO measures, significant differences were noted between cohorts regarding 2-year HOS-ADL (P = .021), Hip Outcome Score Sports-Specific subscale (P = .016), and modified Harris Hip Score (P = .026); otherwise, differences did not reach significance. High rates of 10-year MCID and PASS achievement were seen, with no significant differences between groups. Patients with Tönnis grade 1 had significantly higher rates of conversion to THA compared with patients who had Tönnis grade 0 (25.8% vs 4.8%; P = .006). Patients with Tönnis grade 1 had significantly lower gross survivorship compared with those who had Tönnis grade 0 (71.0% vs 85.5%, respectively; P = .04). Conclusion: Hip arthroscopy confers comparable postoperative clinical improvements to patients who have FAIS with and without mild OA; however, the benefits among patients with mild OA may be less durable. Patients with Tönnis grade 1 had significantly higher conversion to THA and reduced gross survivorship compared with patients with no evidence of preoperative OA, suggesting that patients with evidence of OA may need to be cautioned on the higher rate of conversion surgery.

Objectives: To analyze predictors of clinical failure as defined by revision hip arthroscopy or conversion to total hip arthroplasty (THA) as well as predictors of inferior outcomes defined as the not reaching Minimally Clinical Important Difference (MCID) or Patient Acceptable Symptomatic State (PASS) for Hip Outcome Score-Activities of Daily Living Subscale (HOS-ADL). Methods: Prospective data on all patients who underwent primary hip arthroscopy with routine capsular closure for the treatment of femoroacetabular impingement syndrome (FAIS) by a single, fellowship-trained surgeon between January 2012 and November 2015 were collected and analyzed. Inclusion criteria consisted of clinical and radiographic diagnosis of symptomatic FAIS, failed conservative management, and undergoing hip arthroscopy to correct FAIS with a minimum of two-year follow-up. Exclusion criteria consisted of prior ipsilateral hip surgery and hip arthroscopy for an indication other than FAIS. Baseline demographic data and radiographic parameters were collected and patient-reported outcomes (PROs) were obtained at baseline and at a minimum of two-years postoperatively. Rates of clinical failure and inferior clinical outcomes were recorded at a minimum of two-years postoperatively then stepwise linear regression was used to identify patient-related and imaging-related factors as predictors of each, respectively. Results: Out of 1,161 eligible patients, 949 (81.7%) completed PROs at a minimum of two-years postoperatively. The average age was 32.8 ± 12.4 years with a mean BMI of 25.4 ± 10.7 kg/m2. The overall clinical failure rate was 2.2% (n=21) including eleven cases of revision hip arthroscopy and eleven cases of conversion to THA (one patient underwent revision then subsequent THA). The inferior clinical outcome group consisting of patients who failed to reach MCID for HOS-ADL included164 patients while those who failed to reach PASS for HOS-ADL included 353 patients. In the regression model, poor articular cartilage, hypertension, lateral rim impingement on physical exam, history of back pain/spine pathology, limp on presentation, decreased daily physical activity, greater preoperative alpha angle, weakness in abduction with knees extended, and prolonged symptom duration were predictive of clinical failure (all p-values&lt;0.05). Predictors of failing to reach MCID for HOS-ADL included: prolonged symptom duration, history of back pain/spine pathology, Tonnis grade &gt;1, being a current/former smoker, pain with ischial palpation, lateral rim impingement, snapping iliotibial band, and pain with resisted sit-up and over the greater trochanter. Predictors of failing to reach PASS for HOS-ADL included: prolonged symptom duration, decreased daily physical activity, workman’s compensation, history of anxiety and/or depression, snapping iliotibial band, limp on examination, and pain with palpation of the spine/sacroiliac joint (all p-values&lt;0.05). Conclusion: The clinical failure rate of hip arthroscopy may be lower than previously reported. Reoperation is predicted by medical comorbidity, lack of preoperative athletic activity, and multiple positive physical exams. Inferior clinical outcomes are predicted by prolonged symptom duration, back pain, being a current/former smoker, a history of a psychiatric comorbidity, as well as numerous signs on physical examination.

ABSTRACTTargeted physiotherapy programs (TPP), and surgery, using either open surgical hip dislocation or hip arthroscopy (HA), are the treatment modalities available for femoroacetabular impingement syndrome (FAIS). Randomized controlled trials have recently been performed to compare these treatment options. This review was performed to provide a focused synthesis of the available evidence regarding the relative value of treatment options. A systematic search was performed of Medline, Embase, Cochrane Library and ClinicalTrials.gov databases. Inclusion criteria were randomized controlled trials comparing treatment methods. The Cochrane Risk of Bias assessment tool (RoB2) was used to assess the selected studies. A meta-analysis was performed between homogenous studies. Four trials were identified including 749 patients (392 males). The mean ages of the cohorts ranged between 30.1 and 36.2 years old. Three hundred thirty-five patients underwent HA by 46 surgeons among all trials. Fifty-two patients crossed over from the TPP to the HA group. One of the trials was found to have a high risk of bias, while the other three were between low risk and some concerns. The iHOT-33 was the most commonly used patient-reported outcome measure followed by the HOS ADL and EQ-5D-5L. Others scores were also identified. Scores from two trials could be pooled together for meta-analysis. Apart from SF-12 and GRC, all other scores have shown significantly better outcomes with HA in comparison to TPP at 8- and 12-months follow-up points. HA offers better patient-reported outcomes than TPP for management of FAIS at 8- and 12-months follow-up.

The Fragility Index of Hip Arthroscopy Randomized Controlled Trials: A Systematic Survey