Lisfranc injury: Difference between revisions

(added 1mm =unstable)
Tag: mobile edit
Line 20: Line 20:
*AP
*AP
**Medial margin of 2nd metatarsal base doesn't align w/ medial margin of 2nd cuneiform
**Medial margin of 2nd metatarsal base doesn't align w/ medial margin of 2nd cuneiform
**Bony displacement 1mm or greater between bases of first and second metatarsals is considered unstable
*Oblique
*Oblique
**Medial margin of 3rd metatarsal doesn't align w/ medial margin of 3rd cuneiform
**Medial margin of 3rd metatarsal doesn't align w/ medial margin of 3rd cuneiform

Revision as of 20:11, 12 March 2015

Background

  • Lisfranc Injury = any fx or dislocation of the tarsal-metatarsal joint
  • Lisfranc ligament attaches 2nd metatarsal to medial cuneiform
    • 2nd metatarsal is held in mortice created by the three cuneiform bones
      • Injury to 2nd metatarsal often results in dislocation of the other MTs
  • Dorsalis pedis may be injured in severe dislocation

Epidemiology

  • 20% are missed on first presentation to ED
  • Up to 1/3 of inuries are from minor slip/fall

Clinical Features

  • Inability to bear weight (especially on tiptoe)
  • Tenderness over tarsometatarsal region
  • Pain with pronation and passive abduction of the midfoot
  • Ecchymosis of plantar section of midfoot is highly suggestive

Imaging

  • Fx of base of second metatarsal is pathognomonic
  • AP
    • Medial margin of 2nd metatarsal base doesn't align w/ medial margin of 2nd cuneiform
    • Bony displacement 1mm or greater between bases of first and second metatarsals is considered unstable
  • Oblique
    • Medial margin of 3rd metatarsal doesn't align w/ medial margin of 3rd cuneiform
  • Lateral
    • 2nd metatarsal is higher than middle cuneiform (step-off)
Lisfranc injury

Differential Diagnosis

Foot and Toe Fracture Types

Hindfoot

Midfoot

Forefoot

Treatment

  • Sprains and non-displaced fractures:
    • Non-weightbearing splint w/ ortho f/u (most pts managed w/ cast x6wk)
  • Displaced fractures:
    • Emergent ortho consult
  • Most Lisfranc fractures require surgery

Complications

  • Must rule-out compartment syndrome

See Also

Source

  • Tintinalli