A socioeconomic analysis of intraoperative neurophysiological monitoring during spine surgery: national use, regional variation, and patient outcomes

Abstract

Object In the United States in recent years, a dramatic increase in the use of intraoperative neurophysiological monitoring (IONM) during spine surgeries has been suspected. Myriad reasons have been proposed, but no clear evidence confirming this trend has been available. In this study, the authors investigated the use of IONM during spine surgery, identified patterns of geographic variation, and analyzed the value of IONM for spine surgery cases. Methods In this retrospective analysis, the Nationwide Inpatient Sample was queried for all spine surgeries performed during 2007–2011. Use of IONM (International Classification of Diseases, Ninth Revision, code 00.94) was compared over time and between geographic regions, and its effect on patient independence at discharge and iatrogenic nerve injury was assessed. Results A total of 443,194 spine procedures were identified, of which 85% were elective and 15% were not elective. Use of IONM was recorded for 31,680 cases and increased each calendar year from 1% of all cases in 2007 to 12% of all cases in 2011. Regional use of IONM ranged widely, from 8% of cases in the Northeast to 21% of cases in the West in 2011. Iatrogenic nerve and spinal cord injury were rare; they occurred in less than 1% of patients and did not significantly decrease when IONM was used. Conclusions As costs of spine surgeries continue to rise, it becomes necessary to examine and justify use of different medical technologies, including IONM, during spine surgery.

Intraoperative Neuromonitoring for Anterior Cervical Spine Surgery

“…11,17,9,35,36 Furthermore, we found that corpectomies may be higher risk with a neurological injury rate of 1.02%.…”

Demographic Trends in the Use of Intraoperative Neuromonitoring for Scoliosis Surgery in the United States

“…The intuitive reason for the utility of ION is to raise warning against devastating neurologic complications that can be prevented with intervention, such as reducing the degree of distraction, adjusting retractors, removing hardware, and minimizing the length of surgery. 13 In a retrospective study of 443 194 patients by James et al, 14 the utilization of ION within the United States increased from 1% of all spine procedures in 2007 to 12% in 2011, which are lower than the 37.6% overall utilization rate in scoliosis surgery found in this study. This difference can be accounted for by the inclusion of a wide range of spinal procedures including microdiscectomy in the study by James et al 14 These procedures traditionally do not utilize ION to the same degree as scoliosis surgery.…”

“…13 In a retrospective study of 443 194 patients by James et al, 14 the utilization of ION within the United States increased from 1% of all spine procedures in 2007 to 12% in 2011, which are lower than the 37.6% overall utilization rate in scoliosis surgery found in this study. This difference can be accounted for by the inclusion of a wide range of spinal procedures including microdiscectomy in the study by James et al 14 These procedures traditionally do not utilize ION to the same degree as scoliosis surgery. Furthermore, studies have shown no clear benefit or even recommendation against ION in certain low-risk spinal procedures.…”

Utility of Intraoperative Neuromonitoring for Lumbar Pedicle Screw Placement Is Questionable

“…Contrary to our results, they reported a steady increase in neuromonitoring rates for lumbar procedures from 0.6% to 12.6% from 2007 to 2011, and showed regional differences in neuromonitoring usage. 22 However, their inclusion criteria was not selective and included all lumbar procedures (including fusion and non-fusion surgeries), and also included all forms of ION (not just limited to EMG). Additionally, their data included 15% non-elective cases, a subset of patients that were excluded from our dataset.…”