OVERVIEW

  • The elbow serves to position the hand in space.
  • The muscles acting here are often denervated in brachial plexus and proximal peripheral nerve injury patterns.
  • With dysfunction at the elbow, the upper extremity cannot be properly positioned in space to perform normal functions even if normal hand or other distal function is preserved.
  • Restoration of elbow movement must be a priority in peripheral nerve injury patients.

Structures of the Elbow

  • Bones:
    • Humerus
    • Radius
    • Ulna
  • The elbow joint is a hinge joint.

Movements of the Elbow

  • Flexion and extension are movements about a coronal axis.

Muscles of the Elbow (with detailed examination links)

Muscle NameInnervationBasic Action
Biceps brachiiMusculocutaneous nerveElbow flexion, forearm supination.
BrachialisMusculocutaneous nerveElbow flexion.
BrachioradialisRadial nerveCan assist in elbow flexion (with forearm in neutral position).
Triceps brachiiRadial nerveElbow extension.
AnconeusRadial nerveElbow extension.
Extensor carpi radialis longusRadial nerveExtends the wrist (weak assistance in elbow flexion).
Pronator teresMedian nervePronates the forearm (weak assistance in elbow flexion).

Italics — Muscles that assist or may assist but are not the primary action of elbow joint flexion and extension. These include muscles that cross the elbow joint.