Thumb Ulnar Collateral Ligament Rupture


Thumb Ulnar Collateral Ligament Rupture, Game Keeper's Thumb, Gamekeeper's Thumb, Thumb UCL Injury, Skier's Thumb, Stener Lesion, UCL Sprain of the Thumb, Ulnar Collateral Ligament Sprain of the Thumb

  • Pathophysiology
  1. Ulnar collateral ligament rupture at thumb from forced abduction
  2. Historically named for gamekeepers who broke the neck of small mammals with their hands
  3. Occurs at first metacarpophalangeal joint (thumb base)
    1. Fall on Outstretched Hand (FOOSH)
    2. Skier falls with pole strap wrapped at wrist
    3. Pole strap levers thumb into abduction and extension
  4. Radial collateral ligament tear may also occur instead
    1. Not common
  • Anatomy
  • Ulnar collateral ligament
  1. Proper ulnar collateral ligament (UCL)
    1. Attaches dorsal First Metacarpal head to ulnar base of proximal phalanx
  2. Accessory ulnar collateral ligament (UCL)
    1. Attaches volar First Metacarpal head to ulnar base of proximal phalanx
  • Signs
  1. Pain at medial base of thumb (ulnar aspect)
  2. Test active and passive thumb abduction
  3. Assess thumb metacarpophalangeal joint (MCP) laxity
    1. Laxity with 35 to 40 degrees of joint opening (or no clear endpoint) is considered abnormal
    2. Compare with uninjured side
    3. Apply valgus stress at MCP joint (radially deviating the thumb) in each of 2 positions
      1. Test proper UCL with thumb flexed to 30 degrees at MCP joint
      2. Test accessory UCL with thumb in extension at MCP joint
  4. Assess for Stener Lesion (associated with Grade III injuries)
    1. Displaced distal end of ruptured ligament
    2. Proximal UCL trapped outside adductor aponeurosis
    3. Presents as tender mass at UCL, and joint instability
    4. Requires surgery
  • Differential Diagnosis
  • Grading
  • Compare to uninjured side
  1. Grade 1 sprain: No laxity
  2. Grade 2 sprain: Increased laxity >15 degrees, but firm endpoint
  3. Grade 3 sprain
    1. Increased laxity with no firm endpoint
    2. Joint opening usually >30 degrees
  • Imaging
  1. Hand XRay (AP, Lateral and Oblique Views)
    1. Evaluate for Fracture
      1. Epiphyseal Fracture in children and teens may also occur in this region
      2. Sesamoid bone at the MCP is a normal finding and may obscure injury findings
    2. Proximal phalanx volar subluxation may be present
      1. Related to dorsal capsule or Volar Plate Injury
  2. UCL Ligament Ultrasound
    1. Test Sensitivity approaches 92%
  3. Hand MRI
    1. Indicated in unstable Grade III UCL Ruptures
  • Management
  1. Indications for Surgical Repair: Unstable thumb
    1. No endpoint in abduction of thumb
  2. Initial: Splinting for 6 weeks
    1. Molded plastic thumb lock immobilizer or
    2. Thumb Spica Cast or splint
  3. Later: Dynamic Splinting for additional 6 weeks
    1. Indicated for athletes - splint during sports only
    2. Use one of splints above or taping
    3. Dorsal Taping (0.5 inch tape)
      1. Apply anchor strips at wrist and over distal thumb
      2. Start tape at anchor strip at wrist
        1. Apply over web space between thumb and index
        2. Attach at distal anchor strip on thumb
      3. Build upwards with consecutive tapes
  4. Return to sports
    1. May participate if splinted and no pain or reinjury
  • Management
  • Orthopedic Referral Indications
  1. Associated Fracture present (esp. displaced Fracture)
  2. Grade 3 sprain (see above)
  3. Stener Lesion (associated with Grade III injury)
  • Complications
  1. Unstable MCP joint with weak pincher grasp
  2. Osteoarthritis
  • References
  1. Dolbec (2019) Crit Dec Emerg Med 33(1): 17-25
  2. Broder (2023) Crit Dec Emerg Med 37(8): 20-1