A “skier’s thumb” is a common injury to the hand. Skier’s thumb refers to an acute injury to the ulnar collateral ligament (UCL) of the thumb metacarpophalangeal (MP) joint. This often occurs from a sudden, force, such as when the thumb is bent backwards or jammed. This injury is referred to as a “skier’s thumb” given the frequency it occurs on the ski slopes. It may occur during a fall while holding a ski pole as the handle suddenly forces the thumb away from the hand. Of course, not just skiers get a “skier’s thumb”, as the injury is common in other athletes or people who fall on an outstretched hand.
The thumb MP joint is primarily stabilized by the soft tissue structures surrounding the joint, specifically the ligaments and joint capsule. Ligaments are strong, fibrous tissues which connect bones to other bones. A stable thumb MP joint allows us to pinch, grasp, and use our hands effectively. Without an intact ulnar collateral ligament, pinching with the thumb can be weak and painful. Opening jars, turning keys, and even light tasks can be difficult without a healthy thumb. The risk of degenerative joint disease (arthritis) is also increased when a joint is unstable.
The diagnosis is made based primarily on history, physical exam, and x-rays. Most patients can report a sudden injury to the thumb associated with pain, swelling and possible bruising around the joint. Physical exam includes evaluation of the stability of the joint and possible injuries to the bones, joints, tendons, ligaments, nerves, and blood vessels in the thumb and hand. X-rays are helpful to evaluate for a fracture of the joint. Stress x-rays can be obtained in clinic if the stability of the joint is not clear on physical exam. During a stress x-ray, slight pressure is applied to the thumb to test the ligaments while the x-ray is taken. Rarely, ultrasound imaging or MRI can be helpful for diagnosis.
What are the treatment options?
The treatment plan will depend on the severity of the injury and the patient’s medical condition. Injury severity ranges from a minor sprain to a full-thickness tear of the ligament. This has been classified into 3 grades: grade I is a sprain of the UCL; grade II is a partial tear of the UCL; grade III is a full-thickness tear with joint instability. Most people have sprains or partial tears of the UCL (grade I or II). If the joint is stable on examination, surgery is not usually required. Treatment in these cases is typically rest and protection in a cast or full-time brace for 4-6 weeks. Activities are resumed as comfort permits, but forceful pinching is discouraged for about 2-3 months from the injury. It is very common to have some swelling and “aching” pain in the thumb for 6 months after the injury, particularly during strenuous activities.
Skier’s Thumb Surgery
Some patients have injuries which are more severe and the stability of the joint can be compromised. When a full-thickness tear of the UCL occurs (grade III injury), healing of the ligament to the bone can be difficult. In many cases, the adductor aponeurosis tissue is interposed between the ligament and the bone. This condition is known as a “Stener lesion.” In other words, the ligament cannot heal properly because it is displaced too far and blocked from its natural position. Non-surgical treatment is unreliable in these cases. Surgery is usually recommended to secure the ligament back down to the bone. This is performed typically with a suture anchor which reattaches the ligament to the bone. See image below. Most patients regain strength and range of motion guided by hand therapy.