Medial collateral ligament complex of the elbow

Dr Alex Ansaldo and Dr Henry Knipe et al.

The medial (ulnar) collateral ligament (MCL/UCL) complex is a major stabilizer of the elbow joint and resists valgus stress.

The MCL complex runs from the humerus to the ulna and is composed of three parts 1,3,4,7:

  • anterior bundle
    • inferior medial epicondyle to the sublime tubercle of the medial coronoid process
    • cord-like
  • posterior bundle
    • medial epicondyle to medial olecranon
    • thickening of the joint capsule
  • transverse (or oblique) bundle (Cooper's ligament
    • runs between the inferior fibers of the anterior and posterior bundles (i.e. medial olecranon to medial coronoid process)
    • almost no role in elbow stabilization
  • accessory ligament (a.k.a. extra band): posterior joint capsule to transverse ligament (25%) 1
  • the anterior band is the only part of the MCL complex which is delineated as a separate structure and is best seen on coronal images
Anatomy: Upper limb

Anatomy: Upper limb

Article information

rID: 29742
Section: Anatomy
Synonyms or Alternate Spellings:
  • Medial (ulnar) collateral ligament complex
  • Ulnar collateral ligament complex
  • Triangular ulnar collateral ligament

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