CHONDROBLASTOMA OF THE FOOT

A total of 322 cases of chondroblastoma were referred to the Armed For ces Institute of Pathology between 1960 and 1990. Ten additional cases of chondroblastoma were treated at Waiter Reed Army Medical Center be tween 1985 and 1993. Forty-two of these involved the foot, two of whic h were treated at Waiter Reed Army Medical Center. Patients with chond roblastoma of the foot were male in 35 (81%) cases, with a mean age of 25.5 years, which was significantly different from the mean age of 17 .3 years in patients with chondroblastoma of the long bones (P < 0.000 1). Chondroblastoma of the foot is most commonly found in the posterio r subchondral areas of the talus and calcaneus as well as in the calca neal apophysis. Radiographically, the lesion was associated with an ar ticular surface or apophyseal area in all cases and appeared radioluce nt, with little to no matrix production. The margins were generally we ll defined. Cystic features were noted grossly and histologically in 2 4 (57%) specimens, a feature seen in only 21% of all chondroblastomas overall. Treatment consists of thorough curetting and bone grafting wi th good oncologic and functional results.