POSTERIOR VERTEBRAL BODY EROSION BY ARACHNOID DIVERTICULA IN CAUDA-EQUINA SYNDROME - AN UNUSUAL MANIFESTATION OF ANKYLOSING-SPONDYLITIS

Cauda equina syndrome is an uncommon complication of longstanding anky losing spondylitis; It is associated with dorsal arachnoid diverticula , which may erode the lamina and spinous processes of the bony lumbosa cral spine. We describe a patient who developed cauda equina syndrome associated with the unusual finding of erosion of the posterior aspect of 2 vertebral bodies by arachnoid diverticula. This was clearly reve aled by magnetic resonance imaging of the spine.