Thinning or rupture of the ulnar collateral ligament (UCL) often leads to valgus instability in overhead throwing athletes. This injury is most common in pitchers and other overhead throwers, for example, javelin throwers.
The medial UCL is divided into three components: the anterior oblique ligament, the posterior oblique ligament and the transverse ligament. Elbow stability is due to both soft tissue structures and osseous (bony) structures. The UCL is the primary restraint from 30 to 120 degrees of elbow bending.
Risk factors associated with UCL injury to the elbow include exceeding youth baseball pitch count and inning restrictions, deficits along the kinetic chain and pitching at higher velocities. Kinetic chain deficits include limitations in shoulder mobility and weakness of shoulder girdle and core musculature (or imbalances).
Athletes may report experiencing a “pop” during throwing and associated pain. They may also experience loss of throwing velocity, control and performance.
On exam, there is often tenderness to palpation in the area of injury. In addition to motion testing and a neurovascular exam, laxity of the elbow joint can be tested with a hands-on examination.
X-rays are performed to rule out a fracture or avulsion injury or loose bodies/calcifications of the UCL. Gravity or manual stress views of the elbow may be indicated. MRI may be ordered to assess the integrity of the UCL, often with dye.
Initial management includes rest, elevation, physical therapy, protection of the injury and anti-inflammatories. Physical therapy is incorporated to aid the return to full, desired activities and to address limitations of the kinetic chain found on examination.
UCL anterior band ligament reconstruction (Tommy John Surgery) may be indicated in high-level throwers who wish to continue competitive play. Following surgery, a period of post-operative rest follows, along with a guided course of physical therapy.