Intra-articular extraskeletal myxoid chondrosarcoma of the ankle.

We describe an extremely rare case of an intra-articular extraskeletal myxoid chondrosarcoma causing devastating destruction to the ankle joint in a 71-year-old woman, which had been originally excised as a ganglion cyst. Histological analysis of the lesion revealed an extraskeletal myxoid chondrosarcoma. The patient proceeded to curative surgery with a below-the-knee amputation.