Hereditary multiple exostoses (HME) is the most common type of bone dysplasia, which was first described by Boyer in 1814. It is characterized by the growth of cartilage-capped benign bone tumours (osteochondromas and exostoses) around areas of active bone growth, particularly the long bones metaphysis. Exostoses can involve all bones, but invariably spare the skull and the face. It is a rare pathology that occurs in around 1 in 50,000 individuals. HME is a bone disorder with an autosomal dominant pattern and incomplete penetrance associated with the mutation of: WXT 1, of the long arm of chromosome 8; EXT 2 and EXT 3 of the short arm of chromosome 19. Spinal involvement is rare, represent roughly 3% of cases and any portion of the vertebral body may be affected, anterior and posterior. A review of the literature since 1843 revealed 53 cases of vertebral osteochondromas. Although it is a benign bone disease, malignant degeneration is possible; it represents 20% of the patients affected by HME. A careful analysis of the symptoms and their characteristics as the progression and the age of onset, can lead to the suspect of malignant transformation and its evolution in chondrosarcoma.
Last date updated on July, 2014