The ulnar collateral ligament (UCL) of the elbow is critical for valgus stability of the elbow and is the primary elbow stabilizer.
As such, the UCL plays an important role in most throwing sports, including baseball and javelin, as well as racquet sports and ice hockey.
Elbow injuries in young athletes are generally chronic, with persistent pain and instability from repetitive overhead activities. In the athlete, ligamentous injury can also be heralded by an acute traumatic event such as an elbow dislocation. This can then lead to chronic pain and valgus instability. An understanding of the anatomy and biomechanics of the elbow in throwing sports is essential to the correct diagnosis and treatment of this potentially disabling injury.