[X-ray computed tomographic aspects of lumbar articular synovial cysts with intraspinal development].

CT scan imaging findings are described in 22 patients with lumbar spine joint synovial cysts, of intraspinal development, provoking sciatica or lumbosciatica from nerve compression in spinal canal. Diagnosis was suggested by a mass at the posterior joint level, of variable density, sometimes with peripheral calcification, presenting a vacuum appearance on occasions, and with enhanced image with contrast. Differential diagnosis is from excluded hernia and postoperative fibrosis. Posterior intraarticular arthrography can confirm diagnosis and allow treatment with prolonged action corticoid infiltrations.