In one in ten skiing accidents, the medial collateral ligament of the thumb tears either fully or partly – this injury is known as “skier’s thumb”. But also during many other sports, or even during accidents at home or at work, this ligament on the metacarpophalangeal joint of the thumb can sprain or tear. If pain and swelling occur after violent abduction of the thumb, a visit to a physician and immediate treatment are indispensable.
The metacarpophalangeal joint of the thumb, the connection between the first metacarpal bone and the proximal phalanx of the thumb, is secured by a joint capsule and strong, tension-stable ligaments. The ligaments are there to limit the joint’s mobility and to secure the contact between the articular surfaces. They are not elastic – that’s why they may sprain or tear when excessive force is exerted. Without ligaments, the joint will lose its secure guidance and will become unstable.
Causes: how does skier’s thumb happen?
Skier’s thumb typically occurs when, during a fall, the hand is trapped in the loop of the ski pole and thumb is violently abducted from the index finger. Contrary to its name, this injury also occurs during other sports: ball sports, such as handball and basketball, also pose typical risks, when catching a very powerful pass for example. In the same way, commonplace accidents, for example a fall at home or with the bicycle, can cause a torn thumb ligament.
In cases of skier’s thumb, the medial collateral ligament of the metacarpophalangeal joint of the thumb is affected. It runs from the end of the metacarpal bone along the inside across the joint and is attached on the proximal phalanx of the thumb.
First Aid after a thumb injury
Immediately after this type of thumb injury, those affected can perform First Aid according to the RICE principle. This includes the following steps:
- Rest (stop activity)
- Ice (cooling with ice packs or other cooling applications)
- Compression (applying a gentle compression bandage to prevent extensive swelling)
- Elevation (preventing the arm from hanging down and instead, supporting it at chest/stomach height)
For good measure, a physician should be consulted afterwards.
Symptoms and diagnosis of skier’s thumb
A sprained or even torn (ruptured) ligament causes severe, shooting pain and swelling in the affected area, and often bruising. The thumb – and especially its metacarpophalangeal joint – hurts when touched, and gripping becomes impossible. Additionally, the thumb becomes excessively mobile: the metacarpophalangeal joint can then be “opened up” during an examination, i.e. abducted to far beyond its usual range of motion.
After initial questioning and physical examination, the physician will confirm the diagnosis of skier’s thumb with imaging technology. On X-rays, avulsion fractures or accompanying fractures can be detected. Soft tissue, such as ligaments, however, are not depicted. Magnetic resonance imaging or high-resolution ultrasound images, on the other hand, will show whether and to what extent ligaments and joint capsules are affected.
Treatment and follow-up care of skier’s thumb
When the physician has made a definitive diagnosis, the skier’s thumb is treated immediately. This primarily aims at restoring the ligament – and the ideal guidance of the joint and gripping function of the hand. For this, the injured thumb will be immobilized first. A splint or an orthosis that can be put on and taken off more easily is usually used for this. In cases of partial tears or sprains of the ligament, this protection (for a period of three to four weeks) will suffice.
Subsequent physiotherapy is then used to reverse the loss of strength, dexterity, and mobility caused by immobilization, and to retrain the hand for the demands of daily life.
Skier's thumb surgery: when is it required?
Surgery is needed in cases of a complete rupture to reconnect the ends of the torn ligament. This should happen as soon as possible. Avulsion fractures or what is known as Stener Lesion – trapping of a torn ligament under a neighboring tendon layer – also make surgery absolutely crucial. The ligament often tears right off the bone, meaning it cannot be sutured. Instead, it’s reattached to the area where it tore off using a bone anchor made of biocompatible material. It’s less common for the medial ligament to tear centrally – it can then be fixed with a simple ligament suture.
Skier’s thumb surgery is followed by several weeks’ immobilization in a thumb plaster cast. The plaster cast is removed after approximately five to six weeks and replaced with an orthosis which allows physiotherapy or occupational therapy. Eight to ten weeks after surgery, the medial ligament can usually be subjected to full strain again.
The use of orthoses during treatment and follow-up care
In cases of sprained ligaments or minor tears of the medial ligament, an orthosis, such as the ManuLoc Rhizo, can be used instead of a plaster cast. It reliably stabilizes the metacarpophalangeal joint of the thumb and can easily be taken off and put on again – for example, for physical hygiene or the application of creams. This orthosis can be individually adapted via the integrated aluminum frame and thus provides a comfortable wearing sensation combined with excellent stability. The specially shaped Velcro tab of the ManuLoc Rhizo thumb orthosis allows perfect adjustment and reliable immobilization of the metacarpophalangeal joint of the thumb. Plus, the orthosis’ breathable material provides excellent ventilation to the hand and wrist – as opposed to a plaster cast. This prevents excessive moisture formation as well as itching.
After removal of a plaster cast following surgery, the orthosis also helps heal skier’s thumb: it relieves the affected joint until it has fully healed and prevents awkward movements and tension exerted on the ligament that underwent surgery.