Giant cell tumor of the talar neck.

We describe a patient with a giant cell tumor in the talar head and neck of the left foot who was diagnosed as having osteochondritis dissecans and treated with arthroscopic drilling in this same location 3 years earlier. Giant cell tumors can be confused with several conditions, including giant cell reparative granulomas, brown tumors, and aneurysmal bone cysts. Giant cell tumors of bone typically occur in the epiphysis of long bones, including the distal femur and proximal tibia. They are uncommonly found in the small bones of the foot or ankle, and talar involvement is rare. Despite this rarity, the radiographic appearance and clinical signs of talar lesions should be considered in the differential diagnosis of nontraumatic conditions in the foot.