Insufficiency fracture at an osteochondroma bridging the proximal fibula and the tibia: Case report.

Osteochondromas are benign bone tumors that protrude from underlying bone. A fracture of an osteochondroma is rare, and no insufficiency fractures of an osteochondroma have been reported. A 57-year-old female complained of pain in her proximal leg that increased during walking. A computed tomographic image depicted bridging that had extended to the tibia. An incomplete fracture line was observed at the osteochondroma. The osteochondroma was resected to remove the bridge. The preoperative symptoms disappeared after surgery. It was challenging to diagnose an osteochondroma with an insufficiency fracture because the symptoms varied in accordance with daily activity.