Extensor Carpi Ulnaris

thumb-muscles-2-labeledMuscle Origin

Lateral epicondyle of the humerus to the fifth metacarpal.

It originates from the lateral epicondyle of the humerus and the posterior border of the ulna, and crosses the forearm to the ulnar (medial) side to insert at the base of the 5th metacarpal. Wiki


5th metacarpal.

The extensor carpi ulnaris attaches to the ulnar side of the base of the 5th metacarpal.


Extends wrist.

The extensor carpi ulnaris extends the wrist, but when acting alone inclines the hand toward the ulnar side; by its continued action it extends the elbow-joint. Wiki

Innervation – Nerve control

Deep branch of the radial nerve.

The extensor carpi ulnaris is innervated by Posterior interosseous nerve (C7 and C8), the continuation of the deep branch of the radial nerve. Wiki


Ulnar artery.

The ulnar artery is the main blood vessel, with oxygenated blood, of the medial aspect of the forearm. Wiki

Antagonist muscles

Flexor carpi radialis. Pronator teres, Flexor carpi radialis, Palmaris longus, Flexor carpi ulnaris, Flexor digitorum superficialis, Flexor digitorum profundus, Flexor pollicis longus, Pronator quadratus. American Academy of Manual Medicine

Pictures of muscles


Trigger Point Referrals


Stretching description







Additional Resources

Sports Lab
American Academy of Manual Medicine

Chandler Physical Therapy © 2014 Frontier Theme