Subtalar Dislocation with Isolated Talonavicular Dislocation – A Unique Case

Subtalar joint dislocations are infrequent injuries of the foot involving interruption of the articulations in the subtalar joint complex. These injuries involve dislocation of the talocalcaneal and talonavicular joints simultaneously with or without associated fractures. Subtalar joint dislocations are classified as medial or lateral, with medial dislocations occurring more commonly. Medial subtalar dislocations are generally not associated with other injuries whereas lateral subtalar dislocations are more frequently accompanied by fractures of talus, calcaneus or navicular. Prompt recognition of this dislocation and other injuries prevent negative sequelae associated with delayed treatment, and patients typically have a good outcome and return to prior function with non-operative treatment. Open or very unstable injuries may benefit from temporary internal fixation with Kirchner wires. We present a case of an 81-year-old male who presented to the emergency department with left midfoot pain, swelling and ecchymosis after missing the last rung of a ladder, landing on an inverted foot sustaining an isolated medial talonavicular dislocation. The unique aspect of this case is the intact talocalcaneal joint with isolated medial talonavicular dislocation caused by a low-energy mechanism. After conducting a thorough literature review, we were unable to find other case reports with a similar injury.