Symptomatic intraspinal air entrapment.

A 59-year-old man who had undergone the removal of a lipoma of the thoracic spine presented with progressive weakness of the lower limbs when lumbar puncture followed drainage of a subcutaneous collection of cerebrospinal fluid. Computed tomography showed entrapped intraspinal air which compressed the spinal cord. This rare, but serious complication can occur in a patient with altered intrathecal pressure following spinal surgery.