Learning Radiology xray montage
 
 
 
 
 

Lisfranc Fracture Dislocation



  • Named after Jacques Lisfranc, a field surgeon in Napoleon’s army, who described a new technique for an amputation used to treat frostbite of the forefoot in soldiers on the Russian front
  • Used today to describe fractures and dislocations that occur at the junction between the tarsal bones of the midfoot and the metatarsals of the forefoot

  • Causes

    • Mechanism involves severe plantar flexion of the foot
    • May occur from sports-related injuries
    • Motor vehicle accidents
    • Falling from a height, down stairs or off a curb
  • Ligamentous injuries alone, even without fracture or dislocation, may result in instability on weightbearing
  • Lisfranc ligament diagonally connects the 1st (medial) cuneiform with the base of the 2nd metatarsal
    • If it remains intact, either an avulsion of the lateral border of the 1st cuneiform or an avulsion of the base or medial border of the 2nd metatarsal occurs
    • If it tears, these fractures may not occur

  • Clinical findings

    • Pain at tarsal-metatarsal joints
    • Ecchymosis
    • Instability

  • Types

    • Two basic types

      • Homolateral
        • All of the metatarsals are dislocated to the same side
        • More common than divergent
        • Usually involves the 2nd through 5th dislocated laterally
        • May involve all 5 metatarsals
      • Divergent
        • Usually more severe than homolateral
        • May be associated with a fracture of the 1st cuneiform
        • Usually involves medial displacement of the 1st metatarsal and lateral displacement of 2nd-5th metatarsals
        • Occasionally may involve only medial displacement of only the 1st metatarsal
  • Fractures associated with Lisfranc dislocations
    • Base of 2nd metatarsal
    • Cuboid
    • Fractures of shafts of metatarsals
    • Dislocations of the 1st (medial) and 2nd (middle) and cuneonavicular joints
    • Fractures of the tarsal navicular

  • Imaging

    • Conventional radiographs are usually sufficient to demonstrate the injury
    • Normal alignment of the cuneiforms and the bases of the metatarsals (see chart below)
      • Lateral border of 1st metatarsal is aligned with lateral border of 1st (medial) cuneiform on AP view
      • Medial border of 2nd metatarsal is aligned with medial border of 2nd (intermediate or middle) cuneiform on AP view
      • Medial and lateral borders of the 3rd (lateral) cuneiform should align with medial and lateral borders of 3rd metatarsal on oblique view
      • Medial border of 4th metatarsal aligned with medial border of cuboid on oblique
      • Lateral margin of the 5th metatarsal may project lateral to cuboid by as many as 3mm on oblique
      • On lateral, a line drawn along long axis of talus should intersect long axis of 5th metatarsal

 

Normal Alignment of Tarsal-Metatarsal Joints

Metatarsal

AP Projection

Oblique Projection

1st

Lisfranc with arrows-1

Lateral border of 1st metatarsal is aligned with lateral border of 1st (medial) cuneiform

2nd

Lisfranc with arrows-2

Medial border of 2nd metatarsal is aligned with medial border of 2nd (intermediate) cuneiform

3rd

Medial and lateral borders of the 3rd (lateral) cuneiform should align with medial and lateral borders of 3rd metatarsal

Lisfranc with arrows-3

4th

Medial border of 4th metatarsal aligned with medial border of cuboid

Lisfranc with arrows-4

5th

Lateral margin of the 5th metatarsal can project lateral to cuboid by up to 3mm on oblique

Lisfranc with arrows-5

On lateral view

Line drawn along long axis of talus should intersect long axis of 5th metatarsal

 

    • Stress views of the foot with the patient sedated will usually demonstrate any instability
    • Lisfranc dislocations may be missed in up to 20% of cases
    • Suspect it is present if there is a gap of more than 5 mm between bases of 1st and 2nd metatarsals or 1st (medial) and 2nd  (middle or intermediate) cuneiforms
    • On lateral view, bones of the midfoot will be subluxed or dislocated in a plantar direction



      Lisfranc Fracture-Dislocation.
      The bases of all of the metatarsals
      are dislocated laterally in this homolateral Lisfranc dislocation. There was a fracture of the base of the 2nd metatarsal.

      Lateral view of Lisfranc dislocation. Notice how the bones of the midfoot are dislocated towards the plantar aspect of the foot.

       



  • Treatment

    • Sprains with an otherwise stable tarsal-metatarsal joint can be managed with immobilization
    • Nonanatomic alignment requires open reduction and internal fixation