Ulnar collateral ligament injury (skier’s thumb)

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What is an ulnar collateral ligament (UCL) injury?

A UCL injury is a tear or other damage to the soft tissue that connects the bones of the thumb and provides stability to the thumb joint. The condition is often referred to as skier’s thumb because it is a common injury among skiers. UCL tears are traumatic injuries that cause the thumb to be hyperextended away from the hand, which often happens when skiers fall and their hand is caught in the ski pole.

What causes a UCL injury?

Any injury in which the thumb is abnormally bent backward or to the side can cause skier’s thumb. In addition to skiing, sliding head first during baseball, getting hit while throwing a football, or any racquet or stick sport are commonly reported mechanisms.

What are the symptoms?

Symptoms of a UCL injury include pain, bruising and tender swelling on the inside base of the thumb, at the web space between the thumb and index finger. People may also experience pain and weakness when gripping or pinching something.

If you experience these symptoms, consult your doctor. Failure to seek prompt treatment could lead to chronic pain and instability, diminished hand function and early onset arthritis.

How is a UCL injury diagnosed?

In addition to a complete physical exam and patient history, your doctor may order an X-ray, and sometimes an MRI, to confirm the diagnosis and rule out other damage to your hand.

What is the treatment?

Historically, the recommended treatment for skier’s thumb involved immobilizing the thumb in a cast for four to six weeks. This option may work if the ligament injury is minor. In the majority of cases, however, surgery to repair the UCL is the treatment of choice. UCL repair is a routine outpatient procedure in which the surgeon reattaches the UCL and anchors it with a screw to hold it in place as it heals.