total talar dislocation

Total talar dislocation, also known as extrusion of the talus, is a tri-articular dislocation of talus at the tibiotalar, talonavicular and subtalar joints. Pan-talar dislocation and luxatio tali totalis are also used for such traumatic insult.  Most injuries are compound.

Pathology

Mechanism of injury

Total talar dislocation is a rare injury caused by the combination of tibiotalar plantar flexion, and either excessive subtalar supination or pronation (commonly from motor vehicle accident or fall from height). It results in complete disruption of blood supply and extensive contamination.

The classic scenario is a high energy motor vehicle accident where the driver's foot is plantarflexed, such as when rapidly applying the foot brake, causing the talus to extrude anteriorly. If a severe open injury results, the talus may be found in the foot well of the driver's compartment.

Radiographic features

Plain radiograph and CT

Dislocation of the talus from the mortise joint above, the subtalar joints below and the talonavicular joint anteriorly. The talus usually extrudes anteriorly. There is usually extensive soft tissue injury.

Treatment and prognosis

• wound irrigation, debridement and temporary stabilization of the ankle
• if unable to find talus, tibiocalcaneal fusion and fibular graft is a surgical option

Complications

• talar avascular necrosis
• osteomyelitis
• post-traumatic osteoarthritis

Siehe auch:

• Talusluxation