Results of intraoperative neurophysiological monitoring in spinal canal surgery

Background and purpose: Spine surgery carries the risk of neurological complications. Neurophysiological intraoperative monitoring (NIOM) plays some role in preventing adverse events. NIOM is a young technique, and because of its costs and additional personnel it requires constant evaluation of indications. Nowadays, it is generally assumed that if available, NIOM should be used in every intracanal surgical procedure. This study aimed to evaluate the efficacy and indications for NIOM in spine surgery in relation to procedure location. Material and methods: Effectiveness of NIOM in spinal canal surgery was evaluated by comparison of the number of neurological complications in patients treated surgically with and without NIOM. A total of 74 consecutive patients were surgically treated for spinal canal pathology at the Department of Neurosurgery, 10th Military Hospital in Bydgoszcz. Thirty-eight patients operated on with the use of NIOM were compared to a historic population of 3 6 patients treated before the introduction of NIOM. The number of patients with neurological complications was analyzed in three groups based on surgical location: extradural, intradural extramedullary, and intramedullary procedures. Differences between groups were tested with the Fisher exact test. Results: The number of neurological complications was significantly lower in the intramedullary procedure group with NIOM. There was no significant difference in the number of complications in patients undergoing intra- or extradural extramedullary procedures with versus without NIOM. Conclusions: NIOM decreases the risk of neurological complications in spinal cord surgery, but not in extramedullary spinal canal procedures.