Short extender of the thumb

The extensor short muscle of the thumb is a deep muscle of the posterior region of the forearm.

Located in a medial position with respect to the long abductor muscle of the thumb, it originates from the ulna, the interosseous membrane and the dorsal face of the radium.

With his insertion tendon he crosses the 1st dorsal carpal ligament duct and inserts himself into the dorsal base of the proximal phalanx (1a) of the thumb.

With its action it extends and abducts the thumb (in synergy with the long abductor muscle of the thumb).

It is innervated by the deep branch of the radial nerve (C7-T1), is sprinkled by the superficial palm branch of the radial artery.