Hip arthroscopy for magnetic resonance imaging-verified subspine impingement syndrome: 3-year minimum outcomes study.

PURPOSE: To determine the clinical outcomes of hip arthroscopy for anterior inferior iliac spine subspine impingement (SSI).

LEVEL OF EVIDENCE: Case Series; level IV.

METHODS

Patients who underwent unilateral, primary hip arthroscopy for SSI from February 2015 to December 2017 with minimum 3-year follow-up data were identified (SSI). Analysis of variance, Kaplan-Meier analysis, and regression modeling were used to analyze outcomes.

RESULTS

Of 23 eligible, 19 (83% inclusion) patients (mean [standard error of the mean]: age: 45.9 [3.1]; body mass index, 26.3 [0.9]; 79% female, 53% right side) had a minimum of 3-year follow-up (48.3 [2.2] months). The estimated mean survival time of index procedure across the whole cohort was 64.9 ± 3.1 months. One patient underwent total hip arthroplasty. Patients improved from baseline modified Harris Hip Score (62.7 [5.1]) to follow-up (75.1 [4.3]; P = .014). Twelve patients (63%) met minimal clinically importance difference criteria while 7 (37%) met patient acceptable symptomatic state criteria. Linear regression modeling demonstrated lower postoperative lateral center edge angle (beta = -2.1, 95% confidence interval: -0.5 to -2.9, P = .035) and presence of labral repairs (beta = 46.1, 95% confidence interval: 24.8-67.4, P = .003) were associated with higher follow-up modified Harris Hip Score.

CONCLUSION

In conclusion, patients undergoing anterior inferior iliac spine decompression during hip arthroscopy for SSI in the setting of femoroacetabular impingement syndrome have acceptable, improved clinical outcomes at minimum 3-year follow-up. Labral repair and decreasing postoperative lateral center edge angle were predictive of improved patient-reported outcomes. Hip arthroscopy remains a viable successful treatment options in the treatment of concomitant SSI during femoroacetabular impingement syndrome surgery.