Midterm Outcomes in Patients Undergoing Bilateral Hip Arthroscopy: A Propensity Score–Matched Study With a Minimum 5-Year Follow-up

Background: Bilateral hip symptoms are a common finding in patients with femoroacetabular impingement (FAI). There is a paucity of literature regarding midterm outcomes in patients undergoing staged bilateral hip arthroscopy. Purpose/Hypothesis: The purpose was to present and compare minimum 5-year outcomes between patients who underwent bilateral hip arthroscopic surgery for FAI to a propensity score–matched benchmark control group of patients who underwent unilateral hip arthroscopy and to investigate the effect of time between staged bilateral procedures. It was hypothesized that patients who underwent bilateral hip arthroscopy would demonstrate similar functional outcomes and complication rates compared with those who underwent unilateral surgery. Study Design: Cohort study; Level of evidence, 3. Methods: Data from patients who underwent primary hip arthroscopy from June 2008 to October 2018 were retrospectively collected. Patients who underwent bilateral hip arthroscopy with a minimum 5-year follow-up, including modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score–Sports-Specific Subscale (HOS-SSS), visual analog scale for pain, and patient satisfaction scores, were included. The bilateral group was propensity score matched 1:1 to a control group that underwent unilateral hip arthroscopy based on age, sex, and body mass index. Results: A total of 193 patients (386 hips) were included with a mean age of 33.5 ± 13.6 years and a mean body mass index of 25.5 ± 5.3 kg/m 2 . All 386 hips were propensity score matched to a benchmark control group of patients who underwent unilateral hip arthroscopy. Both groups achieved significant improvements in patient-reported outcome measure scores at a minimum 5-year follow-up, with comparable results between groups. There was no significant difference in the rates of achieving the patient acceptable symptom state and substantial clinical benefit for any patient-reported outcome measure ( P > .05). Patients in the bilateral group with ≤9 weeks between surgical procedures had higher rates of achieving the patient acceptable symptom state for the HOS-SSS ( P = .041). Conclusion: Patients who underwent unilateral and bilateral hip arthroscopy for FAI showed significant and comparable improvements at a minimum 5-year follow-up. Bilateral-presenting patients who underwent staged procedures ≤9 weeks apart met clinically significant thresholds at a higher rate compared with bilateral-presenting patients who had their procedures spaced >9 weeks apart.