skier’s thumb

Ski thumb: description

The ski thumb is the (partial) tear of the ligament at the base of the thumb (ulnar collateral ligament). This band is located on the inside of the thumb (forefinger direction) and is important for the lateral stability in the thumb base joint. It protects the thumb both in extension and flexion from lateral kinking. In principle, such a ligament tear can occur on all fingers. However, the thumb is most often affected.

First and foremost, the ski thumb was known as a gamekeeper’s thumb. The repeated strangulation of small game between index finger and thumb causes the ulnar collateral ligament to become chronically irritated, causing it to tear. Today, the ski thumb occurs most often as an acute injury during sports – just skiing. Up to ten percent of ski accidents involve the thumb metacarpophalangeal joint. In most cases, the tear is at the far end of the tape.

As a complication of the ski thumb a so-called Stener lesion can occur. The distal end of the torn ligament is trapped in the connective tissue tendon plate of the adductor muscles of the thumb and so reverses that healing is difficult.

Ski thumbs: symptoms

After a (partial) tear of the ulnar collateral ligament, the thumb is unstable. Shortly after the accident, the thumb swells as a result of bruising and becomes markedly painful, especially in the area of ​​the metacarpophalangeal joint. In all activities in which the thumb is involved, sufferers notice a (slight) “folding away” of the thumb in its base joint. Typically, the thumb base joint can be “unfolded” a bit. If the injury is a long time back, affected suffer mainly from a weakness and instability of the thumb.

Ski thumbs: causes and risk factors

The most common cause of a ski thumb is the sudden abduction (abduction) of the thumb in the direction of the radius (radial). So the thumb is outstretched, away from the hand. Depending on the strength of the Abspreiz force, the ulnar sideband may tear partially or completely. When skiing the Abspreizdruck is exerted by the snagging in the loop of the ski pole when falling. But also in ball sports, gymnastics and martial arts, a ski thumb can occur. A typical pattern of injury in ball sports is the fall with the hand on the ball. Less often, the ski thumb is the result of chronic damage to the lateral ligament.

Ski thumbs: examinations and diagnosis

Medical specialists for a ski thumb are orthopedists, accident surgeons and sports physicians. First, the doctor will ask questions such as:

• How was the accident mechanism?
• Where are you in pain?
• Can you move your thumb as usual?
• Did you already have injuries in this area?

Then the doctor checks whether blood flow, motor function and sensibility of the thumb are impaired. When examining the hand, the doctor pays particular attention to pain points and painful movements, deformities, swelling and bruising along the ulnar sideband.

In addition, the doctor can check the instability of the ski thumb (Valgusstresstest) measure up. However, if involvement of the bone can not be ruled out, the hand should be x-rayed first. For the test, the thumb is spread in the thumb base joint in maximum extension and in 30 degrees of flexion and measured the degree of maximum spread. Especially important is the page comparison. If the thumb in its base joint can be spread over about 30 degrees or more than 15 degrees in comparison to the opposite side, most likely a ski thumb is present.

Mostly the doctor produces two radiographs (anterior-posterior and lateral). With the help of these images, the doctor can judge whether a piece of bone has ruptured with the band (bony band tear). Pure torn ligaments are not directly recognizable on a simple x-ray. In order to assess the extent of rupture, both thumbs are taken while pacing pressure is applied to the base of the thumb. This allows the ulnar collateral ligament to be evaluated indirectly.

Experienced doctors can also give a clarification of a ski skin ultrasound carry out. Their big advantage is that the thumb and its ligaments can also be examined in motion (dynamic examination). Also one magnetic Resonance Imaging (MRI) is considered a very good imaging technique to diagnose a ski thumb. In very rare cases, one will arthrography recommended an X-ray of the joint after injection of a contrast agent.

Ski thumb: treatment

Immediately after the accident, the injured thumb should be immobilized and, if possible, cooled.

Ski thumb: Operative treatment

If there is a complete tear, a Stener lesion or even a bony ligament rupture, surgery is usually performed. As part of the procedure, the torn ends are reconnected by sutures, suture anchors, wires or mini screws. This usually only a small cut on the side of the thumb is necessary. Optionally, a tendon reconstruction may be necessary. For this material from other tendons or periosteum can be used.

In the case of long-standing injuries, which have led to significant instability or joint wear (arthrosis), surgical band plasty or joint stiffening (arthrodesis) can also be performed. However, this leads to a permanent restriction of movement of the thumb.

Following the operation, the ski thumb is immobilized for about six weeks. Thereafter should be started with the physiotherapy. For around three to four months after surgery, patients should avoid straining the thumb.

Possible risks and undesirable consequences of surgical treatment of a ski thumb are injuries to vessels and nerves, disturbances of temperature sensation (cold intolerance), stiffening and chronic pain. Nervous damage noted during surgery may be repaired immediately.

Conservative treatment

For a ski thumb with partial rupture (and not complete rupture) a conservative therapy is possible. The thumb is immobilized in a cast splint or thumb orthosis for three to four weeks. Thereafter, a movement therapy (physiotherapy) should follow.

Ski thumb: Disease course and prognosis

The prognosis of a professional and early treated ski foam with accompanying physiotherapy is good. Although there is an increased risk of another rupture, however, the thumb can usually be used normally again after completion of the therapy.

Will the skier’s thumb however, not treated, so threatened by the permanent instability of a painful joint arthrosis.