Fig. 5.

Biceps. The biceps muscle originates from the scapula with two heads: the long and short head. The long head located on the side originates from the supraglenoid tubercle of the scapula and the adjacent portion of the glenoid labrum. It passes along the shoulder joint and moves into the intertubercular groove of the humerus, becomes extraarticular although surrounded by a serous sheath, as an extroversion of the synovial fluid of the glenohumeral joint (A, B). It is stabilized by the coracohumeral ligament (C) through (D) and the tendon of the pectoralis major (E), which crosses it and inserts into the pectoral tubercle of the humerus. US image shows normal fibrillar tendon appearance; in the study of the long head of the biceps, short-axis scans are usually sufficient (C, D, E).