Painless root compression following disc extrusion. A report of three cases.

Three cases of painless root compression following disc extrusion are reported. Each patient showed the typical course of disease with the neurological deficit appearing at the same time as the sciatic pain disappeared. At operation the nucleus pulposus was found in the spinal canal. It is suggested that disappearance of the pain is related to the perforation of the anulus fibrosus and posterior longitudinal ligament by the nucleus pulposus. The operative findings justified early operation in these patients, and prompt surgery is recommended for similar cases.