Extensor carpi radialis brevis

The extensor carpi radialis brevis (or extensor carpi radialis brevis muscle, latin: musculus extensor carpi radialis brevis) is a slim, long muscle of the forearm that belongs to the lateral muscle group.

The extensor carpi radialis brevis lies deep, beneath the extensor carpi radialis longus.

Origin

The extensor carpi radialis brevis originates from the lateral epicondyle of the humerus.

Insertion

The muscle descends vertically and inserts at the base of the third metacarpal bone.

Action

The extensor carpi radialis brevis together with the extensor carpi radialis longus provides extension and abduction of the hand.

Innervation

The extensor carpi radialis brevis is innervated by the radial nerve.