Lisfranc injury
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
- 2nd metatarsal is held in mortice created by the three cuneiform bones
- Dorsalis pedis may be injured in severe dislocation
Epidemiology
- 20% are missed on first presentation to ED
- Up to 1/3 of all inuries are from minor slip/fall
Diagnosis
- Inability to bear weight (especially on tiptoe)
- TTP 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/ the medial margin of 2nd cuneiform
- 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)
Treatment
- Lisfranc sprains (normal radiographs) can be managed non-operatively (6 weeks of casting)
- Most Lisfranc fractures require surgery