Young Male Patients With Lower Tönnis Grade and Alpha Angle Are More Likely to Achieve Clinically Significant Outcome Improvement at 2 Years After Hip Arthroscopy for Femoroacetabular Impingement Syndrome Using Periportal Capsulotomy

Purpose To assess predictors for achieving clinically significant outcome (CSO) improvement including minimally clinically important difference, patient acceptable symptom state (PASS), and substantial clinical benefit (SCB), after hip arthroscopy for femoroacetabular impingement syndrome using conservative capsule management with periportal capsulotomy. Methods A retrospective analysis of a prospectively collected single‐institutional database of primary hip arthroscopy for femoroacetabular impingement syndrome patients using periportal capsulotomy between 2015 and 2023 was conducted. Exclusion criteria included hip osteoarthritis, dysplasia, and insufficient 2‐year follow‐up. Patients completed patient‐reported outcomes including the Hip Disability and Osteoarthritis Outcomes Score (HOOS), 12‐Item Short‐Form Health Survey (SF‐12) Physical Component Summary (PCS), and visual analog scale (VAS) surveys at baseline and 2 years postoperatively. CSO attainment was calculated for each patient‐reported outcome, and adjusted multivariable regression analysis was conducted to identify factors associated with CSO attainment. Results Four hundred sixty‐three cases were included (age: 34.0 ± 10.7 years, body mass index: 24.2 ± 3.8, 55.1% women). A total of 94.2%, 76.7%, and 75.4% of patients achieved CSO on PASS, SCB, or minimally clinically important difference for HOOS, SF‐12 PCS, and VAS, respectively. On multivariate analysis, higher preoperative alpha angle was associated with lower odds of attaining all HOOS and VAS CSOs as well as SF‐12 PCS SCB and PASS (odds ratio [OR], 0.92‐0.96; P < .05). Higher Tönnis grade was associated with lower odds of attaining HOOS minimally clinically important difference (OR, 0.35; P = .043) as well as VAS SCB (OR, 0.54; P = .011) and PASS (OR, 0.54; P = .011). Older age was associated with lower odds of attaining SF‐12 PCS SCB (OR, 0.98; P = .024) and PASS (OR, 0.98; P = .021). Male sex was associated with higher odds of attaining HOOS SCB (OR, 2.29; P = .001) and PASS (OR, 2.40; P = .002) as well as SF‐12 PCS SCB (OR, 1.73; P = .016) and PASS (OR, 1.68; P = .021). Conclusions A high percentage of femoroacetabular impingement syndrome patients undergoing hip arthroscopy with periportal capsulotomy achieved CSO improvement at 2 years with younger age, lower Tönnis grade, lower alpha angle and male sex shown as positive predictors. Level of Evidence Level IV, retrospective therapeutic case series.