Pronator Teres
The structure indicated is the pronator teres muscle. The pronator teres is one of four muscles in the superficial layer of muscles in the anterior compartment of the forearm. The anterior compartment of the forearm consists of three layers of muscles:- Superficial layer
- Intermediate layer
- Deep layer
- Flexor carpi ulnaris
- Palmaris longus
- Flexor carpi radialis
- Pronator teres
Origin: humeral head – medial epicondyle of humerus; ulnar head – coronoid process
Insertion: middle of lateral radial surface
Action: pronation, weak flexor of elbow
Innervation: median nerve
Learn more about the anatomy of the muscles of the forearm in this tutorial.