Disc-like herniation in association with gas collection in the spinal canal: CT evaluation.

Gas production as a part of disk degeneration can occur but rarely causes nerve compression syndromes. Few cases have been reported in which lumbar intraspinal epidural gas cause nerve root compression symptoms. We present 12 cases of gas collection in the spinal canal that were presented to the orthopaedic out-patient department with symptoms of low back pain and sciatica. CT showed the presence of free epidural gas collections adjacent to or over the affected nerve roots. Relief of symptoms was noted with the change of positions, lying down or sleeping. In this study, we conclude that the presence of lumbar intraspinal epidural gas that causes radicular compressing phenomena, can be easily detected with the use of CT.