Abstract
A 36-year-old man consulted us, complaining of the left popliteal pain on squating for a couple of years. Roentgenograms and computerized tomography showed transluscent spherical tumor shadow surrounded with ossified shell adjacent to supracondylar posteromedial wall of the left femur. Operative findings: the tumor was covered with periosteum, consisted of grayish white cartilagenous mass. The tumor was resected en bloc. The original cortex lay under the tumor. Microscopic findings: the tumor, surrounded with fibrous tissue and its metaplastic ossified lesion, consisted lesion, consisted of chondrocytes without mitoses and atypism.
