The ulnar collateral ligament (UCL) is present on the inner side of the elbow and connects one of the forearm bones called the ulna to the upper arm bone called the humerus. It provides stability to the elbow, especially during overhead activities such as throwing. Forceful or repetitive throwing (especially overhead throwing), or a fall on an outstretched arm may damage the ulnar collateral ligament causing it to stretch or tear (sprain). This usually occurs during various sports activities.
UCL sprains can lead to pain, tenderness, swelling and limitation in movement. Ligament tears are often associated with a popping sound, reduced throwing velocity, poor grip strength, and numbness in the ring and little fingers.
Ulnar collateral ligament sprains are graded according to severity:
- First degree sprains cause pain to the ligament but no stretching or lengthening.
- Second degree sprains cause pain and stretching of the ligament.
- Third degree sprains result from ligament tears, which significantly affect function.
To diagnose a UCL sprain your doctor will perform a physical examination including clinical tests that examine the UCL. An MRI and other imaging studies may be ordered to identify ligament tears or any other abnormalities.
First and second grade UCL sprains are treated by resting the elbow, ice application, medication and splinting. Third degree UCL sprains are first treated conservatively to reduce pain and swelling. This is followed by surgery to repair or reconstruct the ligament. Your doctor will recommend exercises or a rehabilitation program to stretch and strengthen the ligament, and restore maximum function.