UMEM Educational Pearls

Question

Football player complains of sudden foot pain after begin tackled. What’s the diagnosis? 

Answer

Lisfranc fracture-dislocation

  • Lisfranc joint consists of the tarsometatarsal joint (i.e., mid-foot) complex
  • Injuries occur when bones are fractured/avulsed or there is ligamentous disruption, secondary to a direct force or sudden rotation on a downward pointing forefoot; classic injury was fall from a horse while foot is stuck in the stirrup
  • Examine the Lisfranc joint:
    • Hold heel and twist mid-foot; assess for tenderness
    • Piano-key test: move toes up or down (increases stress in mid-foot)
    • Ask patient to stand on one foot with tip-toes; if not painful, then Lisfranc joint is intact
  • X-ray:
    • Fleck sign: fleck of bone between the first and second metatarsal bases, representing avulsion fracture of the Lisfranc ligament
    • >2 mm displacement between medial cuniform and base of 2nd metatarsal
    • If suspicion remains with normal x-ray, obtain weight bearing x-rays
    • No pain but Lisfranc on x-ray, consider Charcot’s joint
  • Treatment is usually surgical. If fracture is stable and non-displaced (<2 mm) use a short leg cast and non-weight bearing for 6 weeks.

References

Follow me on Twitter (@criticalcarenow) or Google+ (+criticalcarenow)