Overview
It arises on the caudolateral surface of the proximal humerus and spirals down the brachial groove (sulcus musculi brachialis) to the cranial side of the elbow. In the cat it ends on the ulna, together with the tendon of the cleidobrachialis.
Origin
Caudolateral surface of the proximal humerus, distal to the head.
Insertion
Proximal end of the ulna, on its medial side, just distal to the trochlear notch.
Action
Flexes the elbow.
Innervation
Musculocutaneous nerve (n. musculocutaneus).
Clinical relevance
In the distal half of the arm the radial nerve crosses its lateral surface, so the nerve can be injured in fractures of the humeral shaft.