Diagnostic dilemmas in foot and ankle injuries.

Differential diagnosis of foot and ankle injuries should include stress fractures of the great toe sesamoids, the shaft of the fifth metatarsal, and the tarsal navicular bone; transchondral talar-dome fractures; fractures of the os trigonum; and dislocating peroneal tendons. Diagnosis of these injuries is challenging because the initial roentgenograms often are normal, and special clinical tests and ancillary studies are required.