MuscleForearm — posterior
Extensor carpi ulnaris
Latin: M. extensor carpi ulnaris
Location: Forearm
View the extensor carpi ulnaris in 3DOrigin
Lateral epicondyle and posterior border of the ulna.
Insertion
Base of the fifth metacarpal.
Action
Extends and adducts (ulnar-deviates) the wrist — the tennis topspin wrist snap.
Nerve supply
Posterior interosseous nerve (C7–C8).
Blood supply
Posterior interosseous artery.
Clinical relevance
ECU tenosynovitis and subluxation snap over the ulnar styloid in racquet athletes; its sheath stabilises the distal radio-ulnar joint.
Educational anatomy reference, not medical advice. About this content.