616281181
Skier's thumb involves a partial or complete tear of the ulnar collateral ligament (UCL) at the metacarpophalangeal (MCP) joint due to a fall on an outstretched thumb. Another term for this type of injury is "gamekeeper’s thumb," which refers more to chronic, repetitive damage to the UCL. Unfortunately, this seemingly minor injury to a small structure stabilizing the thumb can significantly impact future sports activities and daily quality of life.
Mechanism of Injury in Skier's Thumb
The metacarpophalangeal joint of the thumb is supported by soft tissue structures that provide both static and dynamic stability. The ulnar collateral ligament (UCL) plays a crucial role in this anatomical setup, preventing palmar subluxation of the proximal phalanx and limiting valgus stress during flexion of the MCP joint. Skier's thumb specifically involves damage to the UCL located on the medial side. Far less frequently, the radial collateral ligament (on the lateral side) may be injured. Severe injuries may lead to an avulsion fracture, sometimes described as a fracture of the proximal phalanx base to which the ligament is attached.
This ligament injury typically occurs during skiing accidents when a person falls while holding a ski pole, forcing the thumb into abduction and hyperextension. UCL injuries to the thumb are the second most common skiing-related injury. However, patients reporting to an orthopedic specialist with skier's thumb after a skiing accident constitute only a small percentage. This injury is more commonly noted following a fall from a mountain bike, where the thumb can get caught on the handlebars. A similar injury mechanism may occur in ball-based team sports like soccer, handball, volleyball, and rugby, or in stick-based sports such as hockey.
Symptoms of Skier's Thumb
- Pain at the base of the thumb
- Swelling and bruising of the thumb
- Redness and increased warmth in the affected area
- Tenderness during palpation (touch)
- Weakness in gripping with the thumb and index finger (difficulty forming an “O” shape or using a cylindrical grip)
- Thumb instability
- At least 15 degrees of increased laxity in flexion of the MCP joint compared to the healthy thumb
- Pain exacerbated by movement of the thumb
- Difficulty performing daily activities such as holding a pen, unlocking a door, or opening a jar
Diagnosis of Skier's Thumb
Proper medical examination and imaging diagnostics, such as X-rays or MRI, are essential for diagnosing skier's thumb and deciding between conservative treatment (immobilization and rehabilitation) or surgical intervention. A hand surgeon will conduct a thorough medical interview and clinical examination, checking the range of motion of the MCP joint (both active and passive) within the limits of pain. The physician will also perform specific tests to help establish a diagnosis.
Additional diagnostic imaging may be ordered. X-rays in dedicated views are used to assess the bony structures of the thumb, exclude fractures of the bone shaft, and potentially confirm avulsion fractures (small fragments detached from the bone base).
Ultrasound (US) enables direct visualization of the UCL and surrounding soft tissue structures. Ultrasound can detect a Stener lesion, in which the damaged ligament is displaced above the adductor pollicis muscle, indicating the need for surgical treatment. In cases of diagnostic uncertainty, magnetic resonance imaging (MRI) may be performed. Although more expensive, MRI provides objective visualization of ligament damage and potential avulsion fractures.
Classification of Skier's Thumb
- Grade I: Mild injury with possible partial ligament damage; stable thumb on examination; severe pain on thumb abduction.
- Grade II: Partial ligament tear; severe pain on thumb abduction; instability compared to the unaffected side; noticeable limitation in instability during abduction.
- Grade III: Severe injury with complete ligament rupture; instability observed on examination; opening of the MCP joint with no firm endpoint during abduction.
Treatment of Skier's Thumb
Treatment for skier's thumb can be either conservative or surgical, depending on the extent of UCL (or RCL) damage. If the injured ligament fragment is not displaced or if there are partial tears or avulsion fractures without displacement, conservative treatment is implemented. Immobilization using a thumb orthosis is recommended for 4–6 weeks, followed by a specialized rehabilitation program under the guidance of a physiotherapist. Full return to activity and sports is typically possible after 12–14 weeks, once full thumb function is restored.
Indications for surgical treatment include a Stener lesion, acute injuries with joint opening >35° or >20° valgus/varus deviation at the MCP joint, and chronic injuries causing persistent pain. Surgical treatment involves reinsertion of the injured ligament to its original attachment on the bone using a transosseous suture, anchor, or screw. The procedure should ideally be performed within two weeks of injury. Chronic injuries or delayed treatment may require ligament reconstruction using a tendon graft or MCP joint arthrodesis.
Rehabilitation of Skier's Thumb
After surgery, thumb immobilization is maintained for 4–6 weeks, followed by a specialized rehabilitation program under the supervision of a physiotherapist. Immobilization may involve a plaster splint or a dedicated thumb orthosis. Rehabilitation focuses on rebuilding lost muscle strength, preventing joint stiffness, and gradually restoring full thumb functionality.
Sample Exercises for Skier's Thumb Rehabilitation:
- Touch movement: Bringing the thumb's distal phalanx into contact with the phalanges of fingers 5 to 2.
- Thumb adduction with resistance: Using a Thera-Band for resistance.
Squeezing a ball with the entire hand.
Squeezing a ball using the phalanges of fingers 1–3.
Related Articles:
Explore other potential hand and wrist injuries.
References:
- American Orthopedic Society for Sports Medicine - Skier's thumb—the significance of bony injuries - Beat Hintermann, MD, Peter J. Holzach, MD, Michael Schütz, MD, and Peter Matter, MD - Volume 21, Issue 6
- Ortho Bullets - Thumb Collateral Ligament Injury - Matthew J. Steffes MD
- Bony Skier's Thumb Injuries - Husband, Jeffrey; McPherson, Scott - Clinical Orthopaedics and Related Research: June 1996 - Volume 327 - Issue - p 79-84
- Ulnar Collateral Ligament Injury of the Thumb Metacarpophalangeal Joint - Ritting, Andrew W MD; Baldwin, Paul C BS; Rodner, Craig M MD - Clinical Journal of Sport Medicine: March 2010 - Volume 20 - Issue 2 - p 106-112
