Enchondroma.

Abstract

The enchondroma is one of the most common benign tumors seen in the skeletal system. It is centrally located and in 50per cent of the cases will be found in small tubular bones of the hands or feet where it arises as a hamartomatous process and frequently remains undiagnosed throughout the life of the patient until such time as a pathological fracture through the lesion occurs. The lesion has a typical geographic patern with sharp margination and will frequently demonstrate matrix calcifcationn especially as the patient ages. In the hand or the footn the lesion frequently causes marked thinning of the surrounding cortex and dilatation of the bonen whereas with enchondromas found in larger bonesn there is minimal evidence of cortical invasion and litle if any cortical thinning or dilatation. It is rare for an enchondroma to convert into a chondrosarcoma in the hand or footn but in larger bones such as the femur or pelvisn a primary enchondroma can convert very gradually into a low-grade chondrosarcoma. The incidence of conversion is less than 5 per cent of cases and almost always in adults.