Enchondroma
An enchondroma is a type of noncancerous bone tumor that begins in cartilage. Cartilage is the connective tissue from which most bones develop. Cartilage plays an important role in the growth process. There are many different types of cartilage in the body. An enchondroma most often affects the cartilage that lines the inside of the bones. It often affects the long, tiny bones of the hands and feet. It may also affect other bones such as the thighbone (femur), upper arm bone (humerus), or one of the two lower leg bones (tibia). An enchondroma may happen as one or several tumors. The health conditions that cause multiple tumors include: Ollier disease. This is when multiple areas in the body grow the tumors. Maffucci syndrome. This is a combination of multiple tumors and benign tumors made up of blood vessels (angiomas). Enchondromas are the most common type of hand tumor. They may affect a person at any age but are most common in people ages 10 to 20. They affect men and women equally.