Enchondroma (EC) is a common benign cartilage-producing tumor composed of chondrocytes producing mature cartilage matrix, occurring in the medullary cavity of bone. However, EC originates from the medullary cavity of long bone but very rarely grows in an exophytic pattern forming a prominent mass beyond the cortex, so-called EC protuberans or ecchondroma. The lesion is mostly solitary, but occasionally multifocal affecting one or multiple bones (enchondromatosis).