Extensor digitorum

Extensor digitorum (ED), also known as extensor digitorum communis (EDC), is a muscle of the superficial layer of the posterior compartment of the forearm and with other extensor muscles arises from a common tendon attached to the lateral epicondyle of the humerus. It is one of the extrinsic muscles of the hand. ED represents a medial group of superficial extensor muscles. ED passes under the extensor retinaculum which holds it tight and passes through the 4th extensor compartment of the wrist, once it passes under the sagittal band of the metacarpophalangeal joint the tendon splits into three 'slips' consisting of two lateral slips and a central slip. The lateral slips, run both sides of the proximal interphalangeal joints to then converge with the intrinsic muscles of the hand to form a conjoint tendon, that inserts at the dorsal aspect of the base of the distal phalanx. The central slip inserts at the dorsal surface of the base of the middle phalanx.


Anatomy: Upper limb

Anatomy: Upper limb

Article information

rID: 41591
Section: Anatomy
Tag: refs, refs
Synonyms or Alternate Spellings:
  • Extensor communis
  • extensor digitorum communis
  • extensor digitorum muscle
  • extensor digitorum communis muscle

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Cases and figures

  • Figure 1: extensor compartments of the wrist
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