musculoskeletal and connective tissue disorders
Benign Bone Tumors and Cysts
Enchondroma
Enchondromas may occur at any age but tend to manifest in people aged 10 to 40. They are usually located within the medullary bone metaphyseal-diaphyseal region. These tumors are usually asymptomatic but may enlarge and become painful. They are often found when x-rays are taken for another reason. Periosteal chondromas are similar cartilage lesions that occur on the surface of bones. On x-ray, the tumor may appear as a lobulated calcified area within bone; some lesions are less calcified, with areas of stippled calcification on either plain films or CT. If adjacent to the cortex, enchondromas show minor endosteal scalloping. Almost all enchondromas have increased uptake on a bone scan and thus create false concern of cancer. X-ray findings, including MRI and CT, may be diagnostic; if they are not, and especially if the tumor (not the associated joint) is painful, the diagnosis of enchondroma should be confirmed by open biopsy. To help differentiate bone pain from joint pain, the joint can be injected, usually with a long-lasting anesthetic (eg,bupivacaine); if pain persists, it may be caused by the bone lesion. An asymptomatic enchondroma does not need biopsy, excision, or other treatment (usually curettage); however, follow-up imaging studies are indicated to rule out the rare disease progression to Chondrosarcoma . These studies are done at 6 months and again at 1 year or whenever symptoms develop. Patients with multiple enchondromas (Ollier disease) and especially multiple enchondromatosis with soft tissue hemangiomas (Maffucci syndrome) have a much higher risk of chondrosarcoma. 