Corpus: Ulnar collateral ligament (ellbow)
Synonym: medial collateral ligament
Definition
The ulnar collateral ligament, abbreviated as UCL or MCL, is a collateral ligament of the elbow joint. It extends from the medial epicondyle of the humerus to the medial side of the trochlear notch of the ulna.
Anatomy
The ulnar collateral ligament is the most important ligament for stabilizing the elbow joint and absorbs approximately 55 % of valgus stress in the elbow. It consists of three bundles of fiber tracts:
- An anterior bundle (anteromedial collateral ligament, AMCL),
- A posterior bundle (posteromedial collateral ligament, PMCL), and
- A transverse bundle (Cooper's ligament or Cooper's band).
The ligament serves as the origin for some fibers of the anconeus muscle.
On the opposite side of the elbow, the LCL complex corresponds to the MCL.
Function
The ulnar collateral ligament or the MCL complex stabilizes the elbow joint against applied valgus stress.
Clinic
The ulnar collateral ligament is particularly stressed in throwing sports.