Muscle weakness in patients with symptomatic femoroacetabular impingement (abutment) and tears of the acetabular labrum

Postoperative muscle weakness in patients after hip arthroscopy is an issue that always concerns both the surgeon and the physiotherapists during rehabilitation. In a recent paper, however, an attempt was made to establish whether a reduction in muscle strength is present preoperatively in patients with symptomatic femoroacetabular impingement (abutment) and lesions of the labrum of the acetabulum. For this purpose a study was carried out in a consecutive cohort of patients with unilateral symptomatic femoroacetabular impingement, and a comparison was made with the asymptomatic opposite hip.
The study included 50 consecutive patients who underwent hip arthroscopy for symptomatic femoroacetabular impingement and whose strength was measured preoperatively with a special dynamometer. Various measurements of muscle strength were made: flexion, extension, adduction, abduction, internal rotation and external rotation. A fall in muscle strength of more than 10% for any given measurement was defined as a muscle strength deficit. Other clinical data recorded were age, sex, the size of the labral tear, and the preoperative scores on the hip assessment scale.
The mean age of the patients in this study was 32 years. There were 32 men and 18 women. Muscle strength deficits in abduction were found in 46% of patients and in flexion in 42%. According to the hip assessment scales, patients with a flexion strength deficit showed reduced function and larger labral tears.
The authors concluded that muscle strength deficits were fairly common in patients presenting with unilateral symptomatic femoroacetabular impingement and occurred mainly in abduction and flexion of the hip. Muscle weakness in flexion of the hip was also associated with reduced function, restricted range of motion and larger labral tears.
Source: Arthroscopy, The Journal Of Arthroscopic And Related Surgery, November 2015.