Gamekeeper's Thumb and Skier's Thumb

Thank you to Dr. Aherne for this edition of Morning Report,

Gamekeeper’s Thumb/Skier’s Thumb

Injury to the Ulnar Collateral Ligament (UCL) of the thumb
True gamekeeper’s thumb is a chronic condition, due to repeated valgus force on MCP joint while killing or carrying game, leading to insufficiency of the UCL over time
Skier’s Thumb is an acute injury due to acute hyperabduction of the thumb, typically during a fall on outstretched hand with abducted thumb.
Symptoms: Instability of MCP joint, and pain and weakness with pincer grasp (tying shoes, tearing paper), extreme pain when catching thumb on objects
Signs: swelling, tenderness, ecchymosis around thenar eminence
Stener Lesion: In 80% of complete tears of the UCL, aponeurosis of the adductor pollicis is interposed between MCP joint and the torn ligament, preventing opportunity for healing
Exam:
- Pain control/local anesthetic
- Check for stability; start with the unaffected thumb to evaluate baseline ROM and valgus stability in both extension and 30° flexion
- Check affected thumb for laxity at the MCP joint with valgus stress: radial deviation of >40° in extension, and >20° in flexion
Management:
- Xrays: evaluate for avulsion fx of proximal phalanx at insertion site
- 3mm of volar subluxation of the phalanx on the metacarpal is suggestive of complete UCL rupture
- Stress radiographs to determine extent of instability
- Splint: Thumb spica to immobilize
- Complete Tear/Stener Lesion: Surgery: Ideally within first week; after three weeks, increased incidence of weakness
- 50% failure rate of complete tears treated with bracing and early motion
- Partial tear: 4 weeks immobilization