Intraosseous ganglion. Report of a case.

We report a case of an intraosseous ganglion of the lateral malleolus of the ankle. The lesion was accompanied by a cystic bursa overlying the lateral malleolus. There were connections between the ankle joint, the intraosseous ganglion, and the overlying cyst. Radiographs of the lesion showed the cystic defect in the lateral malleolus surrounded by a sclerotic rim, suggesting that the lesion had progressed very slowly.