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osteochondroma os·te·o·chon·dro·ma (ŏs'tē-ō-kŏn-drō'mə)
A benign cartilaginous neoplasm that consists of a pedicle of normal bone covered with a rim of proliferating cartilage cells.
solitary benign tumour that consists partly of cartilage and partly of bone. Osteochondromas are common and may develop spontaneously following trauma or may have a hereditary basis. No treatment is required unless the tumour interferes with function, in which case it should be surgically removed. Rarely, a solitary osteochondroma will become malignant in adulthood, giving rise to a chondrosarcoma.