Multiple extradural arachnoid cysts as a cause of spinal cord compression in a child. Case report.

Symptomatic arachnoid cysts of the spine are uncommon in children and have only rarely been reported to occur extradurally. The authors report a case of multiple extradural spinal arachnoid cysts in a 9-year-old child who presented with signs of spinal cord compression. The extent of the disease, which affected the thoracic, lumbar, and sacral spine, and the number of independent cysts make this case unique and suggest an underlying defect in the dura of the spinal canal that is predisposed to the formation of cysts. The investigations of choice, surgical planning, and surgical technique are considered. The literature is reviewed and mechanisms of cyst formation discussed.