The palmar cutaneous branch of the median nerve and the palmaris longus tendon: a cadaveric study.

The purpose of this study was to determine the frequency with which the palmar cutaneous branch of the median nerve passes through the palmaris longus tendon. Fifty-two wrists (27 cadavers) were dissected. In three wrists the palmaris longus tendon was absent. The palmar cutaneous branch was seen to course through the fibers of the palmaris longus in two specimens (different cadavers). The nerve passed through the tendon 1 and 1.5 cm proximal to its insertion into the palmar aponeurosis. In the presence of this anomaly the palmar cutaneous branch of the median nerve is at risk of injury during harvesting of the palmaris longus tendon for grafts. To avoid injury, we recommend transecting the tendon 2 cm proximal to its insertion into the palmar aponeurosis.