Tarsal coalition

Tarsal Coalition (also known as Peroneal Spastic Flatfoot  : Calcaneonavicular bar  : Talocalcaneal bar  : Tarsal synostosis  : Tarsal dysostosis) is an abnormal bridge of tissue that connects two normally-separate tarsal bones. The term ‘tarsal’ refers to the seven bones in the rear to mid part of the foot known as the tarsus. The term ‘coalition’ means a coming together of two or more entities to merge into one mass. The term “bar” refers to the abnormal “bar of bone” or fibrous tissue between the two bones. The bones of children are very malleable in infancy. This will generally mean that, despite the presence of a coalition, the bones can deform enough to allow painless walking until the child’s skeleton has matured enough. 'Skeletal maturing' means that bone is laid down in the tissue that forms the immature bone shape gradually until adult bone is achieved at about the age of seventeen years in the feet. Other body parts reach skeletal maturity at different times. The onset of symptoms related to a tarsal coalition usually occurs at about nine to seventeen years of age, with a peak incidence occurring at ten to fourteen years of age.