The humerus in lateral rotation and the elbow supinated.
The long head runs from the supraglenoid tubercle, arches over the humeral head to descend in the intertubercular
sulcus.
The short head arises by a thick flattened tendon from the coracoid apex, together with coracobrachialis.
Both heads are covered by deltoid and pectoralis major. They lead to elongated bellies which, although closely applied can be separated to within a few cm to the distal tendon.
A flattened insertion tendon (6) is attached to the rough posterior area of the
radial tuberosity (2) , medial of the insertion tendon of the supinator (3).
The tendon has a broad medial expansion, the bicipital aponeurosis (1), which
descends medially across the brachial artery to fuse with the deep fascia over the origins of the flexor muscles of the forearm.
A bursa bicipito-radialis (5) separates the tendon from the smooth anterior area of the
tuberosity.
The ramus anterior a. collateralis radialis (4) is lateral of the tendon.
pronator teres (cut) (7)