방골성 골육종과 유사한 슬관절의 거대 활막 연골증식증

Abstract

Synovial chondromatosis is a benign nodular cartilaginous proliferation arising in the synovium of joints. The radiolographic features of this condition are variable. Rarely, it would be confused with malignancy such as chondrosarcoma, osteosarcoma or synovial sarcoma. We re-port a case of primary synovial chondromatosis of the posterior aspect of the proximal tibia mimicking a parosteal osteoarcoma on the radi-ography, which showed a homogeneously radiopaque juxtacortical mass. However, subsequent computed tomography (CT) showed multiple intra-articular masses containing chondroid mineralization, suggesting synovial chondromatosis.