OP3.2 Six-Month Functional Scores Predict 5-Year Outcomes after Hip Arthroscopy for Symptomatic Acetabular Labral Tears

Introduction: Despite the increasing utilization of hip arthroscopy and identification of predictors of poor outcomes, the impact of short-term improvement on long-term functional outcomes has been understudied. The purpose of this study was to determine whether early improvements in patient-reported outcome measures (PROMs) 6 months after hip arthroscopy predict five-year outcomes.

Methods: A retrospective review of prospectively-collected data identified patients >18 years that underwent hip arthroscopy by a single surgeon for the treatment of symptomatic labral tears secondary to femoroacetabular impingement (FAI). Included patients had a Tönnis grade <2 and complete PROMs at baseline, 6-month, and minimum 2-year follow-up. The minimal clinically important difference (MCID) for the modified Harris Hip Score (mHHS) was used to stratify patients into cohorts based on high improvement (HI) versus low improvement (LI) at 6 months. PROMs were compared between these cohorts at 1-5 years postoperatively by rates of MCID achievement and linear mixed effects modeling.

Results: Overall, 175 patients met inclusion criteria. Of these, 131 HI patients were compared to 44 LI patients. At 5 years, 88.3% of HI patients reached MCID, versus 42.1% of LI patients. By multivariate logistic regression, achievement of 6-month MCID (adjusted odds ratio [AOR], 17.42) and labral management (augmentation, relative to debridement: AOR, 14.5) predicted achievement of 5-year MCID. mHHS scores were greater for HI versus LI patients at all time points through 3-year follow-up, but were not significantly different at 4 and 5 years.

Conclusion: Early improvements in PROMs following hip arthroscopy, assessed by 6-month MCID, predicted clinically meaningful outcomes at 5-year follow-up, underscoring the importance of progressive but cautious recovery during these six months. Despite this, LI patients continued improving for 5 years and by absolute PROM scores, did not differ significantly from HI patients at 5-year follow-up, demonstrating that late functional improvement is still possible in patients in the event of a poor 6-month rehabilitation period.