Patients aged 50-75 years take longer to achieve the patient acceptable symptom state than patients aged 20-34 years following primary hip arthroscopy for femoroacetabular impingement syndrome.

Purpose: Though an increasing number of adults older than 50 years are undergoing hip arthroscopy for treatment of Femoroacetabular Impingement Syndrome (FAIS), it is unclear how their timeline for functional outcome improvement compares to that of younger patients. The purpose of this study was to assess the impact of age on time to achieving the Minimum Clinically Important Difference (MCID), Substantial Clinical Benefit (SCB), and Patient Acceptable Symptom State (PASS) following primary hip arthroscopy for FAIS.

Methods: A retrospective comparative single-surgeon cohort study of primary hip arthroscopy patients with minimum 2-year follow-up was conducted. Age categories were 20-34 years, 35-49 years, and 50-75 years. All subjects completed the modified Harris Hip Score (mHHS) prior to surgery and at 6-month, 1-year, and 2-year follow-up. MCID and SCB cutoffs were defined as pre-to-postoperative increases in mHHS by ≥ 8.2 and ≥ 19.8, respectively. PASS cutoff was set at postoperative mHHS ≥ 74. Time to achievement of each milestone was compared using interval-censored survival analysis. The effect of age was adjusted for Body Mass Index (BMI), sex, and labral repair technique using an interval-censored proportional hazards model.

Results: Two hundred eighty-five patients were included in the analysis with 115 (40.4%) aged 20-34 years, 92 (32.3%) aged 35-49 years, and 78 (27.4%) aged 50-75 years. There were no significant differences between groups in time to achievement for the MCID (n.s.) or SCB (n.s.). However, patients in the oldest group had significantly longer time to PASS than those in the youngest group, both in the unadjusted analysis (p = 0.02) and after adjusting for BMI, sex, and labral repair technique (HR 0.68, 95% CI 0.48-0.96, p = 0.03).

Conclusion: Achievement of the PASS, but not the MCID or SCB, is delayed among FAIS patients aged 50-75 years who undergo primary hip arthroscopy compared to those aged 20-34 years. Older FAIS patients should be counseled appropriately about their longer timeline to achieving hip function comparable to their younger counterparts.

Level Of Evidence: III.