Tarsal coalitions: etiology, diagnosis, imaging, and stigmata.

Tarsal coalition is a congenital condition characterized by the aberrant union (osseous or fibrous) between 2 bones in the rearfoot, most commonly talocalcaneal coalition, calcaneonavicular coalition, and talonavicular coalition, that results in a restriction or absence of motion. The association between tarsal coalition and a variety of coexisting conditions has been reported over the past 60 years and continues to be better understood. These coexisting conditions (the stigmata of tarsal coalition) have been believed to be secondary effects of the coalition and/or fixed rearfoot position. Advanced imaging has provided significant insights into the concomitant pathology and understanding of tarsal coalition that the symptoms associated with tarsal coalition can be present for a myriad of different reasons. One should consider all the stigmata of tarsal coalition when considering a surgical reconstruction.