Also called osteocartilaginous exostoses, osteochondroma is an overgrowth of cartilage and bone near the end of the bone near the growth plate. This type of overgrowth can occur in any bone where cartilage eventually forms bone. Most commonly, it affects the long bones in the leg, the pelvis, or scapula (shoulder blade).
Osteochondroma is the most common benign (non-cancerous) bone growth. The lesion usually occurs during skeletal growth—between the ages of 10 and 25 years. It affects males and females equally.