Thumb collateral ligament tear

Thumb collateral ligament injuries include

• radial collateral ligament: rare and generally treated conservatively

• ulnar collateral ligament

  • most common

  • eponyms for ulnar collateral ligament  (UCL) injury are

    • Gamekeeper's thumb for chronic injury

    • skiers thumb for acute injury

    • Stener lesion 

      • avulsed ligament with or without bony attachment is displaced above the adductor aponeurosis

      • will not heal without surgical repair

Physical exam:

• instability in 30° of flexion indicates injury to proper UCL  

• instability in neutral indicates injury to accessory and proper UCL and/or volar plate

• compare to uninjured thumb MCP joint

Imaging

• Xrays AP + L + Oblique

  • avulsion or condylar fracture

  • supination of proximal phalanx (IF UCL injury), and pronation of proximal phalanx (if RCL injury)

  • volar subluxation of proximal phalanx (indicates associated dorsal capsular tear or extensor tendon injury

• MRI: high sensitivity : important to R/O Stener lesion

Treatment

• Nonoperative

  • immobilization for 4 to 6 weeks

    • indications

      • partial tears with < 20° side to side variation of varus/valgus instability

• Operative

  • ligament repair (Suture, anchor, mini screw if bony avulsion)

    • indications: acute injuries with

      • > 20° side to side variation of varus/valgus instability

      • >35° of opening

      • Stener lesion

  • reconstruction of ligament with tendon graft, MCP fusion, or adductor advancement: in chronic injuries