Unlike the flexible flat foot that is commonly encountered in young children, congenital vertical talus is characterized by presence of a very rigid foot deformity. The foot deformity in congenital vertical talus consists of various components, namely a prominent calcaneus caused by the ankle equines or planter flexion, a convex and rounded sole of the foot caused by prominence of the head of the talus, and a dorsiflexion and abduction of the forefoot and midfoot on the hindfoot. [Source: Wikipedia ]