Osteochondroma of the L-5 vertebra: a rare cause of sciatic pain. Case report.

Solitary or multiple osteochondromas, which are benign bone tumors that usually occur in the long bones, are rarely found in the vertebral column. When present in the spine, however, they have a predilection for the cervical or upper thoracic regions. The authors present the case of a solitary osteochondroma arising from the left L-5 articular process that contributed to sciatica; complete cure was achieved following its removal. It is possible to speculate that the cartilage of secondary ossification centers can be the origin of aberrant islands of cartilaginous tissue that cause the osteochondroma to form. The more rapid the ossification process of these centers, the greater the probability that aberrant cartilage will form. Therefore, the fact that osteochondromas are more frequently located in the higher segments of the vertebral column could be explained by the different durations of the ossification processes in these centers, which increase gradually below the cervical segments.