Supraspinatus rupture at the musclotendinous junction: an uncommonly recognized phenomenon

Abstract

The majority of rotator cuff lesions involving the supraspinatus occur at or near the level of bone-tendon interface. We present a series of supraspinatus injuries at the musculotendinous junction. Between October 2002 and December 2009, we prospectively evaluated all patients presenting with an injury of the supraspinatus at the musculotendinous junction. Five patients (1 female and 4 males) were identified. Three patients had a clear history of trauma. All patients presented acutely with pain and muscular edema on T2 magnetic resonance imaging (MRI) sequences. Lesions were characterized as stretch injuries in 2 cases and complete rupture at the level of the musculotendinous junction in 3 cases. Electrodiagnostic studies were normal in all cases. All patients were treated nonoperatively. On clinical and radiological examination at an average of 24 ± 10 months (range, 10-38), 1 patient had complete clinical and radiological resolution, 1 improved, and 3 who complained of loss of function demonstrated severe fatty infiltration on MRI. Musculotendinous rupture of the supraspinatus is an unusual lesion of the rotator cuff. With incomplete injuries, recovery can be anticipated with nonsurgical management. However, in the case of a complete rupture with muscle retraction, nonoperative management leads to unsatisfactory outcomes.