Mobile superior glenoid labrum: a normal variant or pathologic condition?

Abstract

Arthroscopic differentiation between a pathologic superior labrum anterior posterior lesion and a normal anatomic variant may be difficult. Various anatomic patterns exist that systematically characterize superior biceps-labral configurations. One variant involves a mobile superior labrum with exposed articular cartilage on the superior glenoid tubercle. The authors seek to demonstrate that this is nonpathologic. A prospective, consecutive descriptive anatomic study with 1-year clinical follow-up of a subgroup with an identified mobile superior labrum. A total of 191 consecutive patients were prospectively evaluated arthroscopically to quantify the dimensions of the labrum and articular cartilage on the supraglenoid tubercle. A subgroup of 49 patients was identified with articular cartilage on the supraglenoid tubercle, a mobile labrum, and no fibrous tearing or evident injury in this region. In postoperative follow-up, only 1 (2.0%) of these patients was clinically symptomatic in the region of the superior labrum-biceps origin. Indication for repair of a mobile superior glenoid labrum must be carefully addressed in the context of normal anatomic morphologic variability. The labral and supraglenoid tubercle morphology was noted to be highly variable. Patients with mobile labral tissue overlying intact articular cartilage, and no evidence of trauma, are not candidates for repair.