Pediatric Lisfranc injury: "bunk bed" fracture.

A common pediatric fracture is often overlooked due to the subtle deformity of the proximal first metatarsal. The injury is produced during a fall from a height, resulting in a flexion force that wedges the oblique first cuneiform-first metatarsal epiphysis into the first metatarsal-second metatarsal interspace. The injury is more severe than indicated by the bone injury, in that ligaments are involved in subluxation. Anatomic features of the first metatarsal-first cuneiform area present a suitable site for the described injury to occur. The pathogenesis of adult Lisfranc tarsometatarsal dislocation is the model for the pediatric equivalent. The clinical, physical, and radiologic findings of 16 patients are reviewed.