Palmar carpal ligament

The palmar carpal ligament (also volar carpal ligament or Guyon's Tunnel) is a thickened portion of antebrachial fascia on anterior/palmar side of the wrist which - together with the flexor retinaculum of the hand - retains the tendons of most of the flexor muscles of the hand.

The palmar carpal ligament corresponds in location and structure to the extensor retinaculum of the hand also known as the dorsal carpal ligament, on the opposite side of the wrist with which the PCL is continuous as both are formations of the antebrachial fascia. The flexor retinaculum is also known as the transverse carpal ligament.