extensor carpi ulnaris

Muscle of posterior compartment of forearm. Origin: 1) humeral head: lateral epicondyle of humerus 2) ulnar head: oblique line & posterior border of ulna Insertion: base of 5th metacarpal bone Action: extends & adducts hand at wrist Innervation: radial nerve (posterior interosseous nerve)

References

Stedman's Medical Dictionary 27th ed, Williams & Wilkins, Baltimore, 1999