A rare cause of lumbar radiculopathy: spinal gas collection.

The presence of gas in the intervertebral disk space, known as the vacuum phenomenon, is a relatively common radiologic finding, especially on computed tomographic investigation. In a few cases, the gas can be collected into the lumbar spinal canal and can also compress the nerve root. To date only seven cases of symptomatic lumbar radiculopathy caused by a bubble of gas are reported in the literature. The presence of gas inside a narrowed disk and the collection of gas in the spinal canal suggest a communication between the two structures. A case of lumbar radiculopathy caused by a collection of gas in the spinal canal provided the authors the opportunity to study this rare condition by magnetic resonance imaging. Magnetic resonance imaging had not been used before in the referred cases and proved conclusively the discal origin of the gas.