[Scoliosis of sudden evolution due to lumbar osteoblastoma]

The clinical presentation and treatment of a case of osteoblastoma of the lumbar spine (L4) is described, with a notable delay between the onset of symptoms and the definitive diagnosis (2 years). Besides scoliosis, the usual roentgenograms, bone scans, CAT and MRI, did not show any relevant abnormality, which is a possibility that does not allow us to exclude the diagnosis of this tumor in a young patient with lower back pain and a rigid scoliosis.