Congenital vertical talus is a fixed flat foot deformity that causes the sole of a child’s foot to appear to have a convex curve or rocker-bottom appearance. This occurs as a result of the talus and navicular bones being abnormally positioned.
The exact cause of congenital vertical talus is unknown. Studies suggest that the deformity may be caused by abnormal pressure being placed on the foot while the fetus is in the uterus. Another school of thought suggests that the deformity is caused by a muscle imbalance. In either case, stiffness in the hind foot causes the forefoot to ride on top of the talus bone leading to the entire foot being destabilized.
Congenital vertical talus is usually present at birth. The sole of the foot appears convex, the arch of the foot is reversed, and there is a crease on the upper portion of the foot. A callous may form on the sole of the foot at the place where the protruding talus bone touches the ground. If left untreated, it can cause pain in the foot which makes wearing shoes difficult and the child may begin to walk with a “peg leg gait”.
Congenital vertical talus can be diagnosed during a physical examination and x-rays.
It is important to diagnose and begin treatment for congenital vertical talus as early as possible to achieve better results. Casting to manipulate and stretch the foot is the first step in treatment. To complete correction of the deformity, surgery is performed (typically before the age of two) to move the dislocated bones of the foot into proper position and locate the joint between the talus and navicular bones. A tendon release may also be performed if the Achilles tendon has become contracted. Older children may require more complex procedures such as fusion of the talus to the heel bone.