Extensor carpi ulnaris

General information

• This section is strictly limited to anatomy, you might be looking for clinical relevant information which is found under the clinical chapters -- muscles section, click here to go to that page
• Is a part of the lower arms superficial posterior muscle group

Position

• Superficial

Origin

• Lateral epicondylus humerus
• Posterior limitation of ulna

Insertion

• Basis 5. metacarpal, posterior

Main function

• Wrist
  • Extension
  • Ulnar deviation

Secondary function

• Elbow
  • Extension

Nerve innervation

• Segmental
  • C7-C8
• Peripheral
  • Radial nerve

Arterial supply

• Posterior interosseus artery

• Patient position
  • Sitting or supine
• Place your hand just posteriorly on the ulna and feel for the muscle
• Ask the patient to perform extension and ulnar deviation of the hand while you feel for the contraction

• Patient position
  • Sitting or supine
• Ask the patient to hold the lower arm in full pronation
• Give resistance towards the dorsal side of the hand at the 5.metacarpal in a flexion and radial deviation direction, so that the patient is giving force towards extension and ulnar deviation