Extensor pollicis longus

  • The extensor pollicis longus (or extensor pollicis longus muscle, latin: musculus extensor pollicis longus) is a slim muscle of the forearm that belongs to the posterior muscle group, lying in the second or deep layer.

    Origin

    The extensor pollicis longus originates from the posterior surface of the ulna and from the interosseous membrane of the forearm.

    Insertion

    The extensor pollicis longus inserts at the distal phalanx of the thumb - the first digit of the hand.

    Action

    The main function of the extensor pollicis longus is to extend the thumb.

    Innervation

    The extensor pollicis longus is innervated by the radial nerve.