EP3.43 Long-Term Outcomes After Primary Hip Arthroscopy for Femoroacetabular Impingement Syndrome: The Impact of Global Acetabular Retroversion in a Matched Cohort at 15-Year Follow-up

Abstract

Abstract Background Patients with femoroacetabular impingement syndrome (FAIS) due to global acetabular retroversion have increasingly been treated arthroscopically rather than with periacetabular osteotomy. Although this population has shown strong outcomes at 10 year follow up, no evidence exists regarding longer term outcomes in this population. Purpose To compare hip survivorship and patient reported outcomes (PROs) after primary hip arthroscopy between patients with and without global acetabular retroversion at mean 15 year follow up. Methods Retrospective matched cohort study from a single surgeon's prospectively collected hip arthroscopy database. Patients underwent primary hip arthroscopy for FAIS with preoperative radiographs and PROs at both baseline and mean 15 year follow up. Global retroversion was defined by the presence of 3 radiographic signs together: ischial spine sign, posterior wall sign, and crossover sign. Patients were matched 1:1 with FAIS controls by age, sex, and body mass index (BMI). The modified Harris Hip Score (mHHS) and Nonarthritic Hip Score (NAHS) were assessed at baseline, 10 years, and 15 years. Composite failure was defined as revision arthroscopy, conversion to total hip arthroplasty (THA), or failure to achieve the minimal clinically important difference (MCID). Multivariable linear regression evaluated predictors of 15 year outcomes. Results Of 104 eligible patients, 37 met the criteria for global retroversion and were matched with 37 controls. Groups were similar in age (32.0 ± 7.5 vs 34.2 ± 10.6 years; p = 0.673), sex (40.5% vs 40.5% male; p = 1.000), BMI (23.6 ± 3.0 vs 24.0 ± 3.3 kg/m2; p = 0.677), and follow up (14.9 ± 0.7 vs 15.0 ± 0.9 years; p = 0.568). Composite failure was 10.8% in the retroversion group versus 5.4% in controls (p = 0.674). Both groups demonstrated significant improvement in mHHS and NAHS from baseline to 10 and 15 years (p < 0.001). No difference was observed in 15 year mHHS (93.8 ± 11.8 vs 94.6 ± 10.4; p = 0.882) or NAHS (92.2 ± 14.0 vs 93.4 ± 10.5; p = 0.533) between groups. MCID was achieved by 100% of patients in both groups for both mHHS and NAHS at 15 years. Multivariable regression identified no significant association between global retroversion and 15 year PROs. Conclusion Patients with global retroversion undergoing hip arthroscopy for FAIS demonstrated significant, durable improvement in outcome scores at 15 years, with survivorship and PROs similar to those of controls. These represent the longest reported outcomes of arthroscopic treatment for global retroversion.