Intraoperative Neuromonitoring in Percutaneous Spinal Cord Stimulator Placement

Introduction: Placement of spinal cord stimulation (SCS) paddles under general anesthesia using intraoperative neuromonitoring (IONM) has been shown to be associated with equivocal or superior clinical outcomes in comparative studies. The value of IONM in percutaneous permanent SCS placement has not been demonstrated. Methods: Outcomes for patients under percutaneous SCS placement performed with IONM were prospectively collected. Descriptive outcomes included numerical rating scale (NRS), the Oswestry disability index (ODI), McGill pain questionnaire, pain catastrophizing scale score (PCS), and Beck Depression Inventory. We also assessed satisfaction, willingness to repeat surgery, complication rates, and opioid use at baseline and follow-up using chart data and the New York Internet System for Tracking Over-Prescribing data base. Results: The mean follow-up for our 46 patients was 22.04 ± 15.03 months (range 6–52 months). There were 10 patients (21.3%) who underwent revisions or removals with a mean time to revision/explant of 11.4 ± 11.7 months. About 85% of patients were satisfied with surgery. A total of 24 of 46 patients were on opioids at baseline. Following surgery, 17 of 24 (70.83%) patients demonstrated decreased opioid use in Morphine Milligram Equivalents. Of the 17 patients that reduced opioid use, 14 (82.35%) ceased opioid use entirely. Improvement from baseline was noted in NRS, ODI, and PCS (p <.05). Conclusions: Permanent percutaneous implantation of a SCS system using IONM with general anesthesia demonstrates results within range to those in the literature. Patients demonstrated statistically significant improvement in outcomes and opioid use was reduced in 71% of patients who were using opioids at baseline. We recommend its use in patients with morbid obesity, sleep apnea, and considerable anxiety. Further research is warranted to define the possible future role for percutaneous SCS implantation under IONM.