Pronator quadratus

  • The pronator quadratus (or pronator quadratus muscle, latin: musculus pronator quadratus) is a square shaped muscle of the forearm that belongs to the anterior muscle group and is situated in the third or deep layer.

    Origin

    The pronator quadratus originates from the distal quarter of the anterior surface of the ulna.

    Insertion

    The pronator quadratus passes laterally and inserts onto the distal quarter of the anterior surface of the radius.

    Action

    The main function of the pronator quadratus is pronation of the hand and forearm.

    Innervation

    The pronator quadratus is innervated by the median nerve.