The talus bone makes up the ankle joint, and navicular bone is a small bone found in front of it. Congenital vertical talus is a foot deformity in which the talus and navicular bones of the child’s feet are abnormally positioned. This leads to a rigid flat foot with a rocker-bottom appearance. The hind foot points downwards to the floor while the forefoot points upwards. There are deep creases on the upper portion of the foot.
The cause of vertical talus is not clear, but has been associated with certain neuromuscular disorders such as arthrogryposis and spina bifida. It may also be caused by the loss of rotation of the foot or muscle imbalance during early fetal development. In both cases, stiffness in the hind foot causes the forefoot to ride on top of the talus and destabilize the entire foot.
If it is left untreated, the vertical talus adapts and becomes more rigid. On weight-bearing, callouses may form on the sole of the foot at the place where the protruding talus bone touches the ground. It can cause pain in the foot which makes wearing shoes difficult and the child starts walking with a “peg-leg gait”.
This condition should be identified and treated early. Non-surgical treatment involves manipulation, casting and physical therapy in order to stretch the foot and increase flexibility. However, surgery is the mainstay treatment for complete correction of the deformity and should be performed between 9 to 12 months of age. It involves the reduction of the dislocated bones of the foot with the help of pins so they heal in the correct position. Shortened tendons and ligaments as a result of the deformity are lengthened. Your child’s foot is placed in a cast for at least 4 to 6 weeks.