Thumb UCL Injury (Skier’s Thumb)

Ligaments are the strong connective tissue that help stabilize bones to one another. A “sprain” is an injury to the ligaments and can range from a mild injury in which the ligament is stretched to a more severe injury in which the ligament is torn.

A commonly injured ligament in the thumb is the ulnar collateral ligament (UCL) at the MCP joint (“the first knuckle”). This ligament is critical for supporting the thumb during forceful activities and movements such as gripping and pinching.

Injury to the UCL often occurs from a sudden injury in which stress is applied to the ligament. The classic injury by which this occurs is while skiing when the thumb is caught on a ski pole, which is where the name “skier’s thumb” was derived. However, other injuries can include other sports, a fall, or other sudden forceful stress on the thumb. The UCL may also be injured from repeated low energy strain or overuse injuries. This more chronic injury is sometimes referred to as a “gamekeeper’s thumb”.

Milder injuries may result in pain with use of the thumb, particularly with forceful gripping or pinching activities. More severe injuries may result in instability of the thumb. Because of this abnormal motion of the bones in the thumb, this can lead to worsening arthritis over time. For this reason, early recognition and treatment of thumb UCL injuries is important.

Initial evaluation includes a detailed examination of the thumb. This includes an assessment of the stability of the involved joint. X-rays are used to look at the position of the MCP joint. Sometimes there is an associated fracture with UCL injuries. Because ligaments cannot be seen on x-ray, an MRI or ultrasound sometimes is used to better evaluate the ligaments in the thumb, including the ulnar collateral ligament. A specific injury pattern associated with thumb UCL injuries is a “Stener lesion”, which is a high grade injury in which the ligament has torn from its attachment on the thumb and has been caught above a nearby muscle (“adductor pollicis”). In this type of injury, the thumb becomes highly unstable, and the ligament is unable to heal on its own.

Depending on the severity of the injury, initial treatment may involve resting and minimizing use of the thumb by wearing a splint or cast. If this is not successful in healing the injury and resolving the associated pain or if there is a more severe injury (such as a “Stener lesion”), then surgery may be required.

For acute injuries that happened recently, the torn ulnar collateral ligament often can be repaired. Depending on where it is torn, the ligament is sutured back to itself or a special bone anchor may be used if the ligament has torn out of its attachment to the bone. Sometimes, a temporary metal pin will be used to immobilize the joint and to protect the repaired ligament. If there is an “avulsion fracture”, which is a small break of the bone where the ligament attaches, then this bone fragment may be repaired with a metal pin or screw.

If the injury happened more than several months ago, which is known as a “chronic” injury, then reconstruction of the ligament may be necessary. This is the case when repair is not possible due to scarring and contraction of the ligament, which occurs over time following an injury. There are many methods to reconstruct the ulnar collateral ligament, but this typically involves using a small piece of donor tendon from another area on the wrist. It is then attached to the used to recreate that ruptured UCL.

If there is associated arthritis at the same joint (the “MCP joint”), then repair or reconstruction of the ulnar collateral ligament may not treat the underlying pain. This may occur if the injury happened many years ago and remained untreated, which leads to abnormal grinding of this joint and progression to arthritis. In this situation, it may be necessary to fuse or “arthrodese” the MCP joint. Movement will not be possible at this joint after the arthrodesis, but this should eliminate pain associated with arthritis. Fortunately, the thumb has two other important joints for movement (the “IP joint” and “CMC joint”). Thumb function usually remains very good after fusion of the MCP joint.

Recovery is highly dependent on which procedure is performed. With many of the procedures, including repair, reconstruction, or fusion, a prolonged period of immobilization in a splint or cast may be necessary. In certain situations, a particular implant may be used that can improve the stability of the joint and permit early movement and use of the thumb. Hand therapy often is needed to help with recovery, including regaining strength and range of motion. After recovering from surgery, patients should have significant improvement in the pain and instability in their thumb, but there may be a decrease in their thumb range of motion at the MCP joint. However, most people are able to return to their normal daily activities and even high-impact sports.

Be sure to see an experienced surgeon to treat this condition. Our fellowship-trained specialists at The Buncke Clinic in San Francisco treat patients with thumb UCL (skier’s thumb) injuries from across the Bay Area and Northern California. Contact us to schedule a consultation.

Below are links for third party resources

American Society for Surgery of the Hand

American Academy of Orthopaedic Surgeons