Lumbar adhesive arachnoiditis. Etiologic and pathologic aspects.

The etiologic factors and pathologic findings in 38 patients with lumbar arachnoiditis are presented. Lumbar spine surgery and the injection of contrast materials prior to the diagnosis of this condition are considered the most important factors in its genesis. In this series, there was microscopic evidence of arachnoiditis ossificans in 3 patients and arachnoiditis calcificans in 1 patient.