A, Type I fracture. Dorsal fragment usually consists of less than 50% of body of tarsal navicular. Anteroposterior radiographs show only subtle double cortical shadow at joint line. B, Type II fracture. Talonavicular joint is most often subluxated dorsally and medially with adduction of forepart of foot. C, Type III fracture. Comminuted fracture of body of navicular is associated with disruption of cuneiform-navicular joint, lateral deviation of forepart of foot, and injuries to cuboid or anterior process of calcaneus.