Ulnar Collateral Ligament (UCL) Tear

The ulnar collateral ligament is the main ligament stabilizing the inner aspect of the elbow joint during the act of throwing.  It provides the stability which is necessary to throw a ball or to work and lift overhead.  Injury to the ulnar collateral ligament can occur either with chronic repetitive overhead throwing or with one single traumatic event such as falling on an outstretched arm.  If it occurs gradually, there may be a progressive ache or soreness along the inner aspect of the elbow and a throwing athlete may notice decreased velocity and control with throwing.  If it occurs abruptly, there is often a pop followed immediately by pain and swelling.  If the adjacent nerves are injured, some athletes may develop some numbness or tingling in the ring and middle finger. 

Diagnosis

An ulnar collateral ligament injury should be evaluated by a sports medicine physician.  A thorough examination is carried out to determine any instability along the inner aspect of the elbow.  Plain x-rays are often obtained to rule out any type of bony fracture.  An MRI may also be obtained in order to thoroughly evaluate the degree of ulnar collateral ligament injury as well as evaluate for any other elbow joint damage.  A dynamic ultrasound test may also be performed in order to determine if the abnormalities on an MRI are enough to cause functional instability in the elbow joint.