Name

# Extensor Carpi Radialis Brevis

Pronunciation

(eks-TEN-sor KAR-pi ra-de-A-lus BREV-is)

Origin/Proximal Attachment

Lateral epicondyle via the common extensor tendon; radial collateral ligament; antebrachial fascia

Insertion/Distal Attachment

Base of 3rd metacarpal

Action/Relevance

Extends the hand at the wristRadially deviates the hand at the wrist

Innervation

Radial nerve - deep branch (C7,8)

Notes

Extensor carpi radialis brevis originates from the common extensor origin on the anterior aspect of the lateral epicondyle of the humerus. It inserts into dorsal base of the third metacarpal having traversed the extensor retinaculum.

The action of extensor carpi radialis brevis is to extend and radially-deviate the wrist.

It is supplied by the radial nerve via the posterior interosseous nerve, a branch of the radial nerve (C7,C8).