Presentation
Trauma.
Patient Data
There is dislocation of the talus from all its articulations (tibiotalar, talonavicular and talocalcaneal). The talus is rotated and extruded anterolaterally. There are several small comminuted bone fragments along posterior, medial and inferior aspect of the talus. There is comminuted fracture in the posterior process of the talus, middle sustentacular facet of calcaneum and medial malleolus of the tibia with intraarticular extension. Their position and alignment as demonstrated on 3D MPR images. There is diffuse soft tissue swelling through out the ankle, hind and mid foot. There is partial subluxation at calcaneocuboid joint. Overall these described imaging appearances are sequelae of antecedent trauma.
Case Discussion
This is a rarely encountered entity where talus is totally dislocated from its original site with associated comminuted fractures of talus and other talar bones. It is also known as pan-talar dislocation or luxatio tali totalis. Aviator astragalus is an old fashioned reference to a pattern of isolated fracture/dislocation injury of the talus.
For better assessment of associated ligamentous and soft tissue injury, MRI of the ankle joint may be obtained. Urgent opinion from orthopedic surgery is recommended in these cases.
Case courtesy: Dr Jaideep Darira (FCPS,EDIR, FRCR)