J Electrodiagn Neuromuscul Dis.  2021 Apr;23(1):20-23. 10.18214/jend.2020.00122.

Bulbocavernosus Reflex and Pudendal Nerve Somatosensory Evoked Potential in a Cauda Equina Syndrome Patient with Only Lower Sacral Nerve Root Symptoms: A Case Report

• Cho YW
• Kim TH
• Choi C
• Park KD
• Lee JK
• Lim OK

• KMID: 2526169
• DOI: http://doi.org/10.18214/jend.2020.00122

Abstract

Cauda equina syndrome (CES) is a neurological condition involving low back pain, radiating pain, sensory loss, motor weakness, bladder dysfunction, and bowel dysfunction. A 37-year-old man was admitted with saddle-type hypesthesia, bladder dysfunction, and bowel dysfunction, but without motor weakness and radiating pain. He was diagnosed with large sequestrated lumbar disc herniation (LDH) at L5-S1 and underwent decompression surgery. The initial bulbocavernosus reflex (BCR) and pudendal nerve somatosensory evoked potential (PSEP) on postoperative day 10 showed no response. After 1 month, bladder dysfunction and bowel dysfunction improved and saddle-type hypesthesia slightly improved. We also observed improvement in the BCR and PSEP during a follow-up evaluation on postoperative day 35. These results suggest that BCR and PSEP can indicate improvements in clinical symptoms and improved prognoses for CES patients with bladder dysfunction and bowel dysfunction. We report a rare case of atypical CES caused by LDH at the L5-S1 level.

Keyword

Cauda equina syndrome; Bulbocavernosus reflex; Somatosensory evoked potential