Poster 88: Six-Month Functional Scores Predict 5-Year Outcomes after Hip Arthroscopy for Symptomatic Acetabular Labral Tears

Abstract

Objectives:

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 5-year follow-up. The minimal clinically important difference (MCID) for the modified Harris Hip Score (mHHS), 8 points, 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, 2, 3, 4, and 5 years postoperatively by rates of MCID achievement and linear mixed effects modeling. Subsequent surgery rates were compared.

Results:

Overall, 175 patients (age, 37.2 ±11.4 years, 52.0% female) 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 (p<0.001) (Table 1). By multivariate logistic regression, achievement of 6-month MCID (adjusted odds ratio [AOR], 17.42; p<0.001) and labral management (augmentation, relative to debridement: AOR, 14.5; p=0.010) predicted achievement of 5-year MCID (Table 2). mHHS scores were greater for HI versus LI patients at all time points through 3-year follow-up (p<0.05), but were not significantly different at 4 and 5 years (p>0.05) (Figure 1). Subsequent surgery rates were 9.9% and 11.4% in HI versus LI patients, respectively (P>0.05).

Conclusions:

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.