The ulnar collateral ligament (UCL) is a vital part of the elbow joint. This ligament can become damaged due to excessive stress, often leading to pain and instability in the elbow. The UCL is also commonly referred to as the medial collateral ligament or the Tommy John ligament, named after the baseball pitcher who famously underwent surgery to repair a UCL tear. Other synonyms for the UCL include the pronator teres muscle, the flexor carpi ulnaris muscle, and the anconeus muscle. Accurate identification and treatment of UCL injuries are crucial in restoring elbow function and preventing chronic joint damage.