Tarsal coalition: a review of the literature and presentation of 13 cases.

Tarsal coalition refers to the condition that exists when there is absent or restricted movement between two or more of the bones of the hindfoot. The usual cause of the restricted movement is a congenital abnormality with a fibrous (syndesmosis), cartilagenous (synchondrosis), or bony (synostosis) union between the adjoining involved bones. The commonest site of these congenital anomalous attachments are reported in the literature as being located at the calcaneonavicular, the talocalcaneal, and, less commonly, the talonavicular areas. Limited movement in the hindfoot can also result from trauma, arthritis, tumor, or injury involving those joints in the foot. The congenital form may often go unrecognized until such time as a twist or sprain of the ankle or foot leads to its diagnosis. On the other hand, the condition may go unrecognized as a cause for chronic pain or discomfort in the hindfoot or ankle. In this article, a series of 13 feet in 11 patients with this condition that have been noted in the sports medicine clinic at the University of Arizona Health Sciences Center during the past 8 years is described. A detailed historical, clinical, and biomechanical account is also included.