"Floating tibia-talus complex"--an ipsilateral dislocation of the knee and the subtalar joint in an elderly patient: a case report and review of the literature.

Abstract

Knee dislocation is defined as a radiographically confirmed total loss of the tibiofemoral articulation. This rare injury is believed to be the result of a high-impact trauma. Knee dislocations are classified according the direction of tibial displacement with respect to the femur. Subtalar dislocation is the simultaneous dislocation of the distal articulations of the talus at both the talocalcaneal and talonavicular joints. These injuries are also quite rare and are mostly (80%-85%) classified as medial subtalar dislocations with the calcaneus lying medially, the head of the talus being prominent dorsolaterally and the navicular located medial and dorsal to the talar head. The authors report the case of an elderly patient who suffered ipsilateral anterior dislocation of his left knee and medial subtalar dislocation of his left foot. The authors believe this to be the first presentation in the English literature of an ipsilateral combination of these two injuries on the same limb.