Solitary lower lumbar osteochondroma (spinous process of L3 involvement): a case report.

Solitary osteochondromas, which are the most common benign bone tumors of long bones, are rarely found in the vertebral column. A 16-year-old female patient presented with a hard palpable mass at lower lumbar region like a congenital deformity. Plain radiography illustrated a well-defined solid mass arising from the posterior elements of the L3 and ruled out any congenital anomalies. A computed tomography scan further determined a mass that arose from the spinous process of L3. The tumor was excised en bloc through a posterior approach and histopathological examination verified the diagnosis of osteocondroma.Osteochondromas are rarely found in the spine, when present in the spine, however, have a predilection for cervical or upper thoracic region arising usually from lamina of vertebrae and are rare in lumbosacral region and very rare at spinous process of the vertebrae.We present a case of osteochondroma locates in lumbar region and spinous process of vertebrae with unusual presentation and was considered clinically as congenital lumbar kyphosis.