Periosteal osteosarcoma of the calcaneum: a case report.

A 30-year-old woman presented with a 6-month history of pain and swelling over the sole of her right foot. Plain radiograph showed a calcified mass in the heel pad, which appeared to be arising from the spur on inferior aspect of calcaneum. Magnetic resonance imaging showed a lesion, hypointense on T1-weighted and hyperintense on T2-weighted images over the plantar aspect of the foot. Open biopsy of the mass was indicative of periosteal osteosarcoma, the variety that has never been reported in calcaneum. Below-knee amputation was done with no recurrence or distance metastasis seen at 24 months of follow up.