Presentation
Inversion injury.
Patient Data
The talonavicular joint is dislocated with the navicular displaced medially with respect to the head of the talus. Calcaneocuboid alignment is satisfactory. The lateral aspect of the navicular bone demonstrates proximal intra-articular fracture which is impacted. Mild asymmetry of the talocrural joint space but there is no malleolar fracture.
Plaster cast has been applied. The talonavicular dislocation appears to be successfully reduced.
Case Discussion
Subsequent CT (images not available):
Congruency of the midfoot articulations has been restored post reduction. Ankle and forefoot articulations are also unremarkable.
Impacted comminuted fracture of the lateral navicular, results in approximately 4 mm step of the talar facet. Tiny bony fragments projected over the talar neck in keeping with ligamentous injury.
Linear fragment projected over the dorsolateral cuboid is indicative of avulsion injury to either dorsal calcaneocuboid or tarso-metatarsal ligaments.