Hip Strength Before and After Arthroscopic Femoroacetabular Impingement Surgery.

Femoroacetabular impingement (FAI) and labral pathology are associated with pain, decreased function, and hip strength deficits. Existing data are in conflict regarding when hip strength normalizes following arthroscopic treatment of FAI. The objective of this study was to identify preoperative hip strength relative to the contralateral hip not undergoing surgery as well as when postoperative strength in 4 functional muscle groups normalizes following arthroscopic treatment of FAI. Ninety-eight individuals with radiographic evidence of FAI and labral pathology underwent arthroscopic labral repair. Pre-surgical hip strength testing was performed in the symptomatic "surgical hip" and the contralateral "non-surgical hip." Hip strength measurements were repeated at 8 and 16 weeks postoperatively. Significant preoperative hip strength deficits were noted in the surgical hip compared with the non-surgical hip in flexion, extension, and adduction. At 8 weeks postoperatively, hip strength in the surgical hip improved to being equivalent to that in the non-surgical hip in adduction and extension, remained equivalent to that of the non-surgical hip in abduction, and decreased in flexion relative to the non-surgical hip. At 16 weeks, hip strength remained equivalent in the surgical hip and the non-surgical hip in abduction and adduction, but the surgical hip exceeded the non-surgical hip in extension. While flexion strength improved between 8 and 16 weeks postoperatively for the surgical hip, it had not fully recovered to that of the non-surgical hip. Using a structured postoperative rehabilitation protocol, abduction strength was maintained at 8 weeks postoperatively, while adduction and extension strength had improved to those of the non-surgical hip. At 16 weeks postoperatively, hip abduction and adduction had strength equivalent to those of the non-surgical hip. Despite preoperative improvement, flexion of the surgical hip lagged behind that of the non-surgical hip 16 weeks postoperatively. [Orthopedics. 2021;44(3):148-153.].