Intraoperative Neurophysiological Monitoring in Spine Surgery: An Evidence Map of 66 Systematic Reviews With Evidence-Graded Recommendations

Abstract Study Design: Evidence map of systematic reviews with evidence-graded recommendations. Objectives : Guidance on intraoperative neurophysiological monitoring (IONM) in spine surgery rarely links each recommendation to procedure-specific evidence on accuracy, patient outcomes and alert interpretation. We mapped that evidence and derived recommendations whose strength follows its certainty. Methods : PubMed, Scopus and Web of Science were searched to 12 October 2026 for systematic reviews of IONM in spine surgery. Reviews were mapped by procedure and question, with AMSTAR 2 confidence and the GRADE certainty from three companion umbrella reviews that re-analysed deduplicated study-level data. Recommendations were formulated only where review-level evidence existed, and their strength was set with the GRADE evidence-to-decision approach. Results : Sixty-six reviews were mapped; 56 (85%) were of critically low confidence. Evidence was concentrated on diagnostic accuracy in tumour, cervical and deformity surgery, and moderate certainty was limited to evoked potential accuracy in intradural tumour surgery. Fifteen recommendations were made, all conditional: 10 in favour (including multimodal monitoring with motor evoked potentials in intradural tumour and deformity surgery, and an early neurological examination whatever the monitoring findings) 4 against (including routine monitoring in short-segment anterior cervical surgery for radiculopathy) and 1 favouring a risk-based decision in cervical myelopathy. Eight questions, including the effect of alert checklists and blood pressure targets, had no review-level evidence. Conclusions : Most IONM decisions in spine surgery rest on low or very low certainty evidence, so all recommendations are conditional. Prospective comparative studies with standard alert reporting are needed.