Tarsal coalition: review and preliminary conclusions.

Tarsal coalition is a relatively rare anomaly, and the degree of fusion between two or more tarsal bones varies. The coalition may be osseous, cartilaginous or fibrous, and it may be complete or incomplete. It usually results in rigid planovalgus deformity of the foot and may be associated with secondary spasm of the peroneal muscle group. With few exceptions, complete stabilization by arthrodesis is the treatment of choice.