Overview
It arises on the caudal surface of the proximal humerus and spirals down the brachial groove (sulcus musculi brachialis) to the cranial side of the elbow.
Origin
Caudolateral surface of the proximal humerus, distal to the head.
Insertion
Ulnar and radial tuberosities, on the medial side of the proximal forearm.
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.