Usually referred to simply as the biceps, is situated along the anterior of the humerus. The biceps brachii powerfully supinates the forearm when the elbow is flexed. It is also the secondary elbow flexor muscle - the brachialis is the primary flexor - and can assist in several shoulder articulations.
The biceps is composed of two muscular bundles each with its own origin. The short head attaches to the coracoid process of the scapula, and the long head attaches to the supraglenoid tubercle of the scapula just above the glenoid labrum as well as onto the glenoid labrum itself after passing over the head of the humerus.
The long head of the biceps can actually pull the glenoid labrum off the scapula if poor pitching mechanics are used. The result is a SLAP lesion, commonly referred to as a torn labrum.
The insertion of the biceps is on the medial aspect of the radius. The bicipital aponeurosis is a tendon that originates at this insertion, spreads through the fascia of the flexor-pronator mass, and terminates at the ulna.