Comparable Survivorship and Clinically Significant Outcome Achievement With Both Interportal and T-Type Capsulotomy in Contemporary Hip Arthroscopy: A Propensity Score–Matched Analysis

Background: Interportal and T-type capsulotomy are the most common capsulotomy techniques in contemporary hip arthroscopy. Given the critical role of the hip capsule in maintaining joint stability, the extent and configuration of capsulotomy may have meaningful implications for postoperative outcomes. However, investigations directly comparing clinical outcomes of capsulotomy types in a contemporary study population are lacking. Purpose: To compare patient-reported outcomes (PROs), achievement of clinically significant outcomes, and reoperation-free survival between interportal and T-capsulotomy in patients undergoing hip arthroscopy at a minimum 2-year follow-up. Study Design: Cohort study; Level of evidence, 3. Methods: Patients who underwent hip arthroscopy between October 2020 and November 2022 with ≥2-year follow-up were included. Patients with interportal capsulotomy were propensity score matched to patients with T-capsulotomy by age, sex, and body mass index. All patients underwent capsular closure. PROs included the Hip Outcome Score–Activities of Daily Living (HOS-ADL), Hip Outcome Score–Sports Specific Subscale (HOS-SSS), 12-item International Hip Outcome Tool (iHOT-12) score, Patient-Reported Outcomes Measurement Information System–Pain Interference (PROMIS-PI) score, and Patient-Reported Outcomes Measurement Information System–Physical Function (PROMIS-PF) score. Achievement of the minimal clinically important difference (MCID), patient acceptable symptom state (PASS), and substantial clinical benefit (SCB) and reoperation rates were compared. Results: A total of 52 patients with interportal capsulotomy were matched 1:4 to 206 patients with T-capsulotomy (mean age, 32.7 ± 13.8 years; female sex, 85.3%). The mean preoperative alpha angles were not different between groups (interportal: 54.1°± 9.6°; T-type: 56.5°± 9.2°; P = .18). Preoperatively, the interportal group exhibited a higher mean PROMIS-PI score (63.1 ± 5.4 vs 61.0 ± 6.2; P = .02), but similar HOS-ADL, HOS-SSS, and iHOT-12 score ( P ≥ .24). Postoperatively, there was no difference in alpha angles between the cohorts (interportal: 40.7°± 3.3°; T-type: 40.9°± 4.2°; P = .92). There was also no difference in any postoperative PROs ( P ≥ .10). The interportal group exhibited a larger decrease in PROMIS-PI score (−15.8 vs −11.8; P = .03), but no differences were found for any other PRO ( P ≥ .11). There were no differences in rates of achieving the MCID (93.5% and 92.8%, respectively; P > .99), PASS (88.2% and 83.0%, respectively; P = .52), or SCB (78.4% and 77.5%, respectively ; P > .99) between the interportal and T-type cohorts for any PRO. The 2 cohorts demonstrated similar reoperation-free survivorship (98% and 98%, respectively; P = .81). Conclusion: Interportal and T-capsulotomy result in comparable PROs, rates of clinically meaningful improvement, and reoperation-free survivorship at a minimum follow-up of 2 years. These findings suggest that when combined with appropriate capsular closure, either capsulotomy technique provides comparable clinical outcomes for patients not requiring the additional visualization afforded by a T-capsulotomy.