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.
Anatomy and pathomechanics
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.
Typical and severe Lisfranc injuries have extensive ligament disruption and fractures. Recently a "subtle Lisfranc injury" has been described, a category in which displacement of the TMT joint is minimal and may only be apparent on loading. Panchbhavi (2008) shed light on the biomechanics of such injuries. In a cadaver study, Panchbhavi found that instability on simulated end-stance loading could be created simply by dividing the Lisfranc ligament. The instability consisted of abnormal rotational movements between the medial cuneiform and 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.