A, Lateral radiograph of immature foot with middle facet tarsal coalition. B, Lateral radiograph of patient in late 20s showing adaptive changes in middle facet. C, Harris axial calcaneal view. D, CT scan confirms degenerative changes in middle and posterior facets; note adaptive changes of entire shape of calcaneus. E, Oblique radiograph of same foot as in B and D, showing coalition extending distal to middle facet.