Extensor carpi ulnaris

  • The extensor carpi ulnaris (or extensor carpi ulnaris muscle, latin: extensor carpi ulnaris) is a superficial muscle of the forearm that belongs to the posterior muscle group, lying in the first layer.

    Origin

    The extensor carpi ulnaris originates from the lateral epicondyle of the humerus, the posterior surface of the ulna and from the olecranon of the ulna.

    Insertion

    The extensor carpi ulnaris extends vertically downwards and inserts at the base of the fifth metacarpal bone.

    Action

    The main functions of the extensor carpi ulnaris are flexion and adduction of the hand.

    Innervation

    The extensor carpi ulnaris is innervated by the radial nerve.