type A lateral
type A medial
type B1
type B2 partial
type B2 complete
type C1
type C2
NB This page is from the 2005 Hyperbook.
Last evidence check February 2005.
The tarsometatarsal joints are collectively known as the "Lisfranc joint" after the Baron de Lisfranc, a Napoleonic army surgeon who described an amputation through the foot at this level."Lisfranc injuries" refers to a group of bony and/or soft tissue injuries which affect the tarsometatarsal and sometimes other midfoot and forefoot elements.
In transverse section, the metatarsal bases form part of an arch, with the bones wider above than below to fit the arch. The strongest part of the arch is the 2nd TMT joint, which is recessed into a mortise between the medial and lateral cuneiforms. The plantar ligaments are stronger than the dorsal ligaments, and are reinforced by the plantar fascia and intrinsic muscles. The strongest ligament of all is the Lisfranc ligament between the medial cuneiform and the base of the second metatarsal.
Many published series come from major trauma centres and so have 60-80% of multiply injured patients, mostly from road accidents; although Vuori (1993) had only 33% polytrauma. Both Vuori and Mulier (1997) note that severe Lisfranc injuries can be caused by minor trauma. Other causes of Lisfranc injuries include falls from a height and crushing injuries. Myerson (1986) distinguished between injuries caused by direct and indirect trauma, with dorsal displacement in almost all indirect injuries, but only half of direct injuries. About 1/3 of Lisfranc injuries also have fractures of the cuneiforms, cuboid or more proximally, and about 10% are open.
The classification in most common use is that of Quenu and Kuss (1909) as modified by Hardcastle (1979). Myerson (1986) relabelled the classification:
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type A lateral |
type A medial |
type B1 |
type B2 partial |
type B2 complete |
type C1 |
type C2 |
In addition, Faciszewski et al (1990) drew attention to a group of injuries (“subtle Lisfranc injuries”) in which malalignment or divergence of the first and second rays was only apparent on weightbearing. 11% of Vuori’s series had a subtle Lisfranc injury.
Lisfranc injuries should be suspected in patients who complain of midfoot pain and swelling after any trauma. One or more of the rays may appear short. As they are often missed initially, they should be specifically looked for in multiply injured patients at the secondary survey. Examination should include the proximal tarsus also. Patients with such an injury should be checked for injury to the deep peroneal nerve, dorsalis pedis artery and compartment syndrome.
AP, lateral and oblique radiographs are required. The degree of dorsal or plantar displacement may be apparent only on the lateral film. CT may be useful to assess more complex injuries and Lu et al (1997) showed that CT is better than plain radiography on assessing minor incongruity.
On the plain film fractures and malalignment and displacement of the metatarsals relative to the cuboid may be apparent. More subtle injuries may be picked up by measuring the distance between the first and second metatarsal bases (<2mm), looking at the alignment of the lateral aspect of the second metatarsal base with the intermediate cuneiform and looking for the “fleck sign”, an avulsion fracture of the medial base of the second metatarsal by the Lisfranc ligament. If a subtle Lisfranc injury is suspected but not seen on plain radiographs, a weightbearing film may show malalignment.
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| "Subtle Lisfranc" injury - minor gap with fleck sign on NWB film (left) increases on WB film (right) A typeB1 injury | Lateral displacement of 2nd-5th rays (type B2, the commonest) |
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| Complex B2 lateral displacement injury with comminution of 2nd + 3rd MT bases and distal fractures. Plate fixation allows length to be restored | |||
Undisplaced “subtle Lisfranc injuries” may resolve with casting and non-weightbearing, probably for about 8 weeks to allow the ligaments to heal. However, there is a risk of displacement and we would recommend percutaneous screw fixation of these injuries.
Displaced injuries require closed or open reduction and stabilisation with K-wires or screws. Most older series used wire fixation but a cadaver study by Lee (2004) showed that screw fixation, at least of the three medial joints, gives more rigidity. However, there has been no comparative clinical trial of wire versus screw fixation. If screws are used, most authors recommend removal about 3 months after injury, although there is no clear evidence this is necessary.
There has also been a controversy between temporary screw fixation and primary arthrodesis of the TMT joints. Mulier et al (2002) found more complications in patients who underwent arthrodesis, although they may have had more severe injuries. Otherwise there is not enough data to resolve the issue.
Whatever method of reduction and fixation is used, functional outcome is mainly determined by the quality of reduction and the maintenance of that reduction (Myerson 1986, Mulier 1997). Direct injuries probably do worse than indirect injuries and pure ligament injuries than fracture-dislocations.
Almost all patients will develop some degenerative changes but these have little effect on the overall result. About 10-20% will develop symptomatic arthritis requiring arthrodesis (Myerson 1986, Mulier 1997, Kuo et al 2000) and this may be reduced but not avoided by initial ORIF.
Late arthrodesis produced satisfactory results in 70% of patients in Sangeorzan’s series (1990). Poor results were associated with delay in reconstruction. Other causes of poor results from reconstruction include severe soft tissue injuries and regional pain syndromes.