Palmaris Longus Anatomy

Palmaris Longus Muscle

Origin:  Medial epicondyle of the humerus via the common flexor tendon
Insertion:  Central portion of the flexor retinaculum and superficial portion of the palmar aponeurosis
Actions: Assists with flexion of the wrist
Innervation: Median nerve (C7, C8)
Blood Supply: Muscular branches from the ulnar artery

Primary Actions of the Palmaris Longus

1. Because of the size and location the palmaris longus does not have a primary action.


Secondary Actions of the Palmaris Longus

1. Assists with flexion of the wrist


  • Flexor Carpi Radialis
  • Flexor Carpi Ulnaris


  • Extensor Carpi Radialis Longus
  • Extensor Carpi Radialis Brevis
  • Extensor Carpi Ulnaris

2. Tightens the palmar facsia