Magnetic resonance imaging-based classification for ulnar collateral ligament injuries of the elbow.

Background: Magnetic resonance imaging (MRI) arthrography has been considered the gold standard for imaging ulnar collateral ligament (UCL) injuries. No classification system has been described for UCL tears to help discuss and guide treatment options. We propose that an MRI-based UCL classification system would correlate with valgus laxity and help predict surgical management.