Medial collateral ligament injury in the overhand-throwing athlete

Medial collateral ligament injuries are rare and occur almost exclusively in overhand-throwing athletes. The late cocking phase of the overhand throw places a marked valgus moment across the medial elbow. This repetitive force reaches the tensile limits of the medial collateral ligament, subjecting it to microtraumatic injury and attenuation. The anterior bundle of the medial collateral ligament has been identified as the primary restraint to valgus load and is the focus of reconstruction. Diagnosis of medial collateral ligament injuries should be suspected in any overhand-throwing athlete with a history of medial-sided elbow pain, decreased control, and reduced throwing velocity. Injury to the medial collateral ligament can be confirmed by physical examination (moving valgus stress test) and appropriate imaging studies (computed tomography arthrogram and magnetic resonance imaging). Reconstructive techniques of the medial collateral ligament have evolved over time and currently provide superior outcomes, with 80% to 90% of athletes returning to the same level of competitive play. As our understanding of the pathoanatomy of medial elbow injuries progresses and newer hybrid techniques evolve, our ability to care for the overhand-throwing athlete can be expected to improve.