Progressive Contralateral Acetabular Labral Deterioration Occurs Between Staged Bilateral Hip Arthroscopies for Femoroacetabular Impingement Syndrome Without Affecting Clinical Outcomes.

PURPOSE: To evaluate the contralateral acetabular labral changes occurring between staged bilateral hip arthroscopies in patients with femoroacetabular impingement syndrome and to explore their correlation with clinical outcomes with a minimum 2-year follow-up. METHODS: A consecutive cohort of patients diagnosed with bilateral femoroacetabular impingement syndrome that underwent staged bilateral hip arthroscopy between 2011 and 2023 was included. Magnetic resonance imaging of the contralateral hip was obtained at the time of each staged procedure to evaluate labral size and labral tear classification. Preoperative and minimum 2-year patient-reported outcomes (PROs) were collected including modified Harris Hip Score, International Hip Outcome Tool-12, Hip Outcome Score-Activity of Daily Living Scale, Hip Outcome Score-Sports Specific Subscale, University of California at Los Angeles score, and visual analog scale. Rates of achieving the minimal clinically important difference and patient acceptable symptom state were calculated. The relations between acetabular labral changes, possible confounding variables, and PROs were evaluated using correlation analysis. RESULTS: A total of 46 patients were included in the study. The mean interval between staged bilateral procedures was 49.6 ± 39.7 months (range, 8.5-190.6 months). A significant decrease in labral height at the 3:00 position of the contralateral hip was observed between the staged bilateral hip arthroscopies, decreasing from 4.0 ± 0.9 to 3.7 ± 0.9 mm (P = .032). No significant changes in labral size at the 11:30 or 1:30 positions of the contralateral hip were observed between the staged procedures (P > .05). The labral tear classification also presented significant deterioration during the procedures (P < .001), characterized by a decrease in type 1 to 3 tears and an increase in type 4 tears. All PROs showed significant improvements at a mean follow-up of 5.3 ± 1.6 years (P < .001), with high rates of achieving the minimal clinically important difference (>64%) and patient acceptable symptom state (>71%). However, no significant correlations were observed between labral changes, patient characteristics, and PROs (P > .05). CONCLUSIONS: Progressive labral deterioration occurred in the contralateral hip during staged bilateral hip arthroscopies for patients with femoroacetabular impingement syndrome, with a modest but significant reduction in labral height at the 3:00 position and worsening of labral tear classification. Alterations in labral size and labral tear classification showed no significant association with minimum 2-year postoperative outcomes. LEVEL OF EVIDENCE: Level IV, retrospective case series.