Extensor carpi radialis brevis muscle

Extensor carpis radialis brevis (ECRB) is a muscle of superficial layer on posterior compartment of the forearm. It passes through the 2nd extensor compartment of the wrist. ECRB is one of the three muscles forming the mobile wad of Henry. It is one of the extrinsic muscles of the hand.


  • origin: lateral epicondyle of the humerus, annular ligament of the radius
  • insertion: base of 3rd metacarpal on posterior surface with direct relationship with ECRL which inserts into the base of 2nd metacarpal
  • innervation: deep branch of radial nerve, C7, C8
  • action: extension and abduction of the wrist joint; ECRB is a prime extensor of the wrist
Anatomy: Upper limb

Anatomy: Upper limb

Article information

rID: 39869
Section: Anatomy
Tag: anatomy
Synonyms or Alternate Spellings:
  • ECRB
  • ECRB muscle
  • Extensor carpi radialis brevis

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Cases and figures

  • Figure 1: extensor compartments of the wrist
    Drag here to reorder.
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