Sciatic Nerve Entrapment (Deep Gluteal Syndrome) as a Cause of Failed Back Surgery Syndrome: A Case Report

Sciatic nerve entrapment, which is a cause of non-discogenic extraspinal sciatica is characterized by buttock pain and sitting intolerance. If significant asymptomatic lumbar stenosis in the lower lumbar spine is found in patients with buttock pain and sciatica, caused by sciatic nerve entrapment, it is possible that needless spinal surgery may have been recommended. A 72-year-old male presented with a 2-year history of severe buttock and sole pain in his right lower extremity. His pain did not improve after decompression and fusion surgery for severe lumbar stenosis. A pelvic magnetic resonance imaging (MRI) used to evaluate the failed back surgery syndrome revealed a type II variation between the sciatic nerve and piriformis muscle. Transgluteal decompression of the sciatic nerve completely eliminated chronic disability associated with right buttock and sole pain. The patient's pain was improved by sciatic nerve decompression through a transgluteal approach. Although vascular claudication, hip joint pathology, and peripheral neuropathy have been suggested in the differential diagnosis of lumbar stenosis, sciatic nerve entrapment involving the gluteal region should be suspected in patients presenting with buttock pain associated with sciatica, combined with severe lumbar stenosis based on MRI.