Enchondromatosis constitutes a group of disorders, characterized by multiple benign cartilaginous tumors, located primarily in the metaphyseal regions of the tubular bones. The disease is usually diagnosed in childhood. Ollier disease is the best known form of this condition, in which the enchondromas have a predominantly unilateral distribution. Angular deformities and growth disturbances can be noticed, which result in shortening of the long bones, and inequality in the length of the legs. Maffucci Syndrome is another form of the disease, characterized by the association of the multiple enchondromas with soft tissue hemagioma. Although the enchondromas themselves are benign, patients with enchondromatosis carry a higher risk of developing sarcomas, especially osteosarcomas, and chondrosarcomas. The sarcomatous transformation needs to be assessed via biopsy of the affected tissue.
Radiographic findings typically are long low-density streaks projecting through the diaphyses into the epiphyses of the long bone. The tubular bones of the hand appear globular due to expansion. Differential diagnosis includes Hereditary Multiple Exostoses (HME). The lesions can be treated with cutterage and bone grafting. However, the recurrence rate tends to be high after cutterage. At times, inequality in the length of the legs may require surgical correction.
Enchondromatosis has generally been regarded as a non-hereditary, non-familial disease. Only in very few cases has a familial link been implicated. The PTH gene has been purported to be involved in the formation of enchondromas, although not much is known about the underlying molecular mechanism.