Name

# Palmaris Longus

Pronunciation

(par-MA-rus LONG-gus)

Origin/Proximal Attachment

Medial epicondyle of the humerus via the common flexor tendonAntebrachial Fascia

Insertion/Distal Attachment

Central portion of the flexor retinaculum; superficial portion of the palmar aponeurosis

Action/Relevance

Flexes the hand at the wrist

Innervation

Median nerve (C6, 7)

Notes

Palmaris longus arises from the common flexor origin around the medial epicondyle. It is inserted into the tough fascia of the palmar aponeurosis and the flexor retinaculum.

The action of palmaris longus is to flex the wrist and tense the palmar aponeurosis.

It is supplied by the median nerve (C7, C8).

It is absent in approximately 13% of the population.