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 1^st (medial) cuneiform with the base of the 2^nd metatarsal
• If it remains intact, either an avulsion of the lateral border of the 1^st cuneiform or an avulsion of the base or medial border of the 2^nd 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 2^nd through 5^th dislocated laterally
• May involve all 5 metatarsals
• Divergent
• Usually more severe than homolateral
• May be associated with a fracture of the 1^st cuneiform
• Usually involves medial displacement of the 1^st metatarsal and lateral displacement of 2^nd-5^th metatarsals
• Occasionally may involve only medial displacement of only the 1^st metatarsal
• Fractures associated with Lisfranc dislocations
• Base of 2^nd metatarsal
• Cuboid
• Fractures of shafts of metatarsals
• Dislocations of the 1^st (medial) and 2^nd (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 1^st metatarsal is aligned with lateral border of 1^st (medial) cuneiform on AP view
• Medial border of 2^nd metatarsal is aligned with medial border of 2^nd (intermediate or middle) cuneiform on AP view
• Medial and lateral borders of the 3^rd (lateral) cuneiform should align with medial and lateral borders of 3^rd metatarsal on oblique view
• Medial border of 4^th metatarsal aligned with medial border of cuboid on oblique
• Lateral margin of the 5^th 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 5^th 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 1^st and 2^nd metatarsals or 1^st (medial) and 2^nd  (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