Internally Peer Reviewed The most important variation is an additional muscle, subscapularis minor or s. secundus, which arises from the upper part of the axillary border of the scapula and is inserted into the capsule of the joint, onto the crest of the lesser tubercle of the humerus, or somewhat below the lesser tubercle. It was found by Gruber in 10 of 200 limbs. A rarer variation is a slip arising from the subscapular tendon and passing to the axillary fascia and skin at the base of the axilla. A slip connecting subscapularis to pectoralis major has been observed and sometimes the tendon is connected to the short head of the biceps muscle. Gruber saw this variation once in 380 cases studied.
Confusion often occurs when a variant has too many names.
Verlag von Friedrich Vieweg und Sohn, Braunschweig. Observations on the muscular anomalies in the human anatomy. Third series with a catalogue of the principal muscular variations hitherto published. One case of the M. subscapularis minor. The subscapularis muscle.