Systematic Review and Meta-analysis of Studies Comparing Complete Capsular Closure Against Unrepaired Hip Capsules During Hip Arthroscopy

Background: While the biomechanical importance of the hip capsule is well described, there remains controversy over the necessity of routine capsular closure after hip arthroscopy.Purpose: To perform a meta-analysis of clinical studies to compare pooled outcomes of complete hip capsular closure cohorts against unrepaired hip capsule cohorts.Study Design: Systematic review; Level of evidence, 3.Methods: The Cochrane Database of Systematic Reviews, Cochrane Register of Controlled Trials, PubMed, MEDLINE, Web of Science, CINAHL/EBSCO, and Scopus were queried in February 2022 for studies that directly compared clinical outcomes for hip arthroscopy patients treated with either complete capsular closure or an unrepaired capsule. Outcomes assessed were incidence of revision hip arthroscopy, incidence of subsequent conversion to total hip arthroplasty (THA), and improvement from baseline in modified Harris Hip Score (mHHS), Hip Outcome Score (HOS) activities of daily living (ADL), HOS sports specific (SS) subscale, Copenhagen Hip and Groin Outcome Score (HAGOS) ADL, and HAGOS SS subscale. A pooled weighted mean difference (WMD) was used to compare changes in mHHS. A pooled standardized mean difference (SMD) was used to compare changes in the ADL and SS outcomes. A pooled risk ratio (RR) was used to compare the probability of revision hip arthroscopy and conversion to THA based on capsular management. For pooled outcomes where heterogeneity was regarded as potentially unimportant, a fixed-effects model was implemented. For pooled outcomes with considerable heterogeneity, a random-effects model was implemented.Results: Of the 1896 records identified in our search, 11 studies (1897 patients) were included. A significantly higher improvement in mHHS (WMD, -3.72; 95% CI, -4.95 to -2.50; P < .00001) and ADL outcomes (SMD, -0.30; 95% CI, -0.54 to -0.07; P = .01) were seen after complete capsular closure. There was a significantly lower probability of subsequent revision hip arthroscopy (RR, 1.67; 95% CI, 1.14 to 2.45; P = .008) and conversion to THA (RR, 2.01; 95% CI, 1.06 to 3.79; P = .03) after complete capsular repair. There was no difference in SS outcomes (SMD, -0.02; 95% CI, -0.16 to 0.13; P = .81) between the 2 groups.Conclusion: This meta-analysis demonstrated that routine complete capsular closure after hip arthroscopy led to superior clinical outcomes relative to unrepaired hip capsules.