Lateral subtalar dislocation: Case report and review of the literature

Abstract

A case of complicated lateral subtalar dislocation is presented and the literature concerning this injury is reviewed. Subtalar joint dislocations are rare and often the result of a high-energy trauma. Complications include avascular necrosis of the talus, infection, posttraumatic osteoarthritis requiring arthrodesis and chronic subtalar instability. Negative prognostic factors include lateral and complicated dislocations, total talar extrusions, and associated fractures. A literature search was performed to identify studies describing outcome after lateral subtalar joint dislocation. Eight studies including fifty patients could be included, thirty out of 50 patients suffered a complicated injury. Mean follow-up was fifty-five months. Ankle function was reported as good in all patients with closed lateral subtalar dislocation. Thirteen out of thirty patients with complicated lateral subtalar joint dislocation developed a complication. Avascular necrosis was present in nine patients with complicated injury. Four patients with complicated lateral subtalar dislocation suffered deep infection requiring treatment with antibiotics. In case of uncomplicated lateral subtalar joint dislocation, excellent functional outcome after closed reduction and immobilization can be expected. In case of complicated lateral subtalar joint dislocation immediate reduction, wound debridement and if necessary (external) stabilisation are critical. Up to fifty percent of patients suffering complicated injury are at risk of developing complications such as avascular talar necrosis and infection.

Keywords: Trauma, Dislocation, Subtalar joint, Foot injury, Hindfoot surgery, External fixators

Core tip: Subtalar dislocations are a rare and severe injury which is often result of high-energy trauma. Subtalar dislocations represent 1%-2% of all dislocations. The foot is displaced laterally in about 25% of cases. Excellent outcome can be expected in patients with uncomplicated lateral subtalar dislocation if immediate closed reduction is achieved. In case of complicated subtalar joint dislocations requiring open reduction, wound debridement, appropriate joint reduction and additional stabilisation with an external fixation are critical. A complication rate up to 50% can be expected in these patients.