Abstract

A clear understanding of muscle activity is necessary for the rehabilitation of the posterior rotator cuff muscles. Electromyographic (EMG) analyses of the supraspinatus, infraspinatus, and teres minor muscles were done to determine optimum exercises for this muscle group. Twenty-eight subjects were studied using fine-wire intramuscular electrodes in each of the three muscles. A series of tests compared many of the standard exercise positions with several more novel concepts. The EMG activity produced in the supraspinatus was maximized when the subject horizontally abducted the externally rotated humerus while prone. The infraspinatus and teres minor EMG activity were maximized in the prone position with an external rotation movement with the glenohumeral joint at 90 degrees and the elbow at 90 degrees. Verf.-Referat