The case of 16-year-old boy with a spinal extradural arachnoid cyst is presented. An extradural arachnoid diverticulum extending from T10 to L1 was excised totally with hemilaminectomy. Surgery caused prompt improvement of the neurological deficit. The pertinent literature is reviewed.
Key words Spinal arachnoid cyst - extradural - Spinal cord - Paraparesis