FP2.8 Long-term Functional Outcome Scores and Rates of Reoperation After Hip Arthroscopy in Primary and Revision Settings

Background: Prior studies have reported outcomes following revision hip arthroscopy (HA) at short-/mid-term time-points; there remains a paucity of literature comparing clinical outcomes and reoperation rates between patients undergoing primary and revision HA at 10 years postoperatively.

Purpose: To compare patient-reported outcomes (PROs), clinically significant outcome (CSO) achievement, and reoperation rates after HA in both the primary and revision settings at long-term follow-up.

Methods: Patients undergoing HA were identified and revision hips were propensity-matched 1:4 to primary hips by age, sex, and body mass index (BMI). Collected PROs included Hip Outcome Score Activities of Daily Living/Sports Subscale (HOS-ADL/SS), modified Harris Hip Score (mHHS), international Hip Outcome Tool-12 item questionnaire (iHOT-12), Visual Analog Scale for Pain/Satisfaction (VAS-Pain/Satisfaction). Cohort-specific thresholds for minimal clinical important difference (MCID) and patient acceptable symptomatic state (PASS) were calculated, and CSO achievement was determined. PROs, CSOs, and rates of reoperation including total hip arthroplasty (THA) and revision HA were compared.

Results: Thirty-two revision hips were propensity matched to 128 primary hips with similar follow-up time (10.9±0.52 vs. 10.9±0.48, p≥0.350). Both groups saw statistically significant improvement in PROs pre- to post-operatively (p<0.001, for all) with no noted differences across groups at 10-years postoperatively (p≥0.123, for all). Revision hips had lower MCID achievement for VAS-Pain (63.2vs.85.7%, p=0.044) and PASS achievement for HOS-SS (36.8%vs.62.1%, p=0.047); otherwise, no statistical differences in MCID or PASS achievement were observed (p≥0.263). Rates of subsequent arthroscopy were similar between groups (12.5%vs.9.4%, p=0.529). Revision hips underwent THA conversion more frequently than in primary hips (18.8%vs.4.7%, p=0.015), with 83.3% (5/6) of the THA conversions in the revision cohort occurring >4.5 years after revision HA.

Conclusions: Revision and primary HA cohorts demonstrated significant improvement in all PROs, however revisions may have lower achievement of CSOs. Re-revision rates were in line with primary revisions at long-term follow-up; conversion to THA occurred more frequently after revision HA with subsequent THA occurring most frequently at time points beyond 4.5 years.