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 2^nd 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)