Diagnostic accuracy of motor evoked potentials to detect neurological deficit during idiopathic scoliosis correction: a systematic review

Abstract

<jats:sec> <jats:title>OBJECTIVE</jats:title> <jats:p>The goal of this study was to evaluate the efficacy of intraoperative transcranial motor evoked potential (TcMEP) monitoring in predicting an impending neurological deficit during corrective spinal surgery for patients with idiopathic scoliosis (IS).</jats:p></jats:sec> <jats:sec> <jats:title>METHODS</jats:title> <jats:p>The authors searched the PubMed and Web of Science database for relevant lists of retrieved reports and/or experiments published from January 1950 through October 2014 for studies on TcMEP monitoring use during IS surgery. The primary analysis of this review fit the operating characteristic into a hierarchical summary receiver operating characteristic curve model to determine the efficacy of intraoperative TcMEP-predicted change.</jats:p></jats:sec> <jats:sec> <jats:title>RESULTS</jats:title> <jats:p>Twelve studies, with a total of 2102 patients with IS were included. Analysis found an observed incidence of neurological deficits of 1.38% (29/2102) in the sample population. Of the patients who sustained a neurological deficit, 82.8% (24/29) also had irreversible TcMEP change, whereas 17.2% (5/29) did not. The pooled analysis using the bivariate model showed TcMEP change with sensitivity (mean 91% [95% CI 34%–100%]) and specificity (mean 96% [95% CI 92–98%]). The diagnostic odds ratio indicated that it is 250 times more likely to observe significant TcMEP changes in patients who experience a new-onset motor deficit immediately after IS correction surgery (95% CI 11–5767). TcMEP monitoring showed high discriminant ability with an area under the curve of 0.98.</jats:p></jats:sec> <jats:sec> <jats:title>CONCLUSIONS</jats:title> <jats:p>A patient with a new neurological deficit resulting from IS surgery was 250 times more likely to have changes in TcMEPs than a patient without new deficit. The authors' findings from 2102 operations in patients with IS show that TcMEP monitoring is a highly sensitive and specific test for detecting new spinal cord injuries in patients undergoing corrective spinal surgery for IS. They could not assess the value of TcMEP monitoring as a therapeutic adjunct owing to the limited data available and their study design.</jats:p></jats:sec>

Intraoperative neurophysiology monitoring in scoliosis surgery in children

“…An evidence-based guideline update on intraoperative spinal monitoring with somatosensory and transcranial electrical motor evoked potentials ( Nuwer et al, 2012b ) concluded that INM is effective to predict an increased risk of paraparesis, paraplegia and quadriplegia in spinal surgery. A systematic review ( Thirumala et al, 2017 ) of the diagnostic accuracy of motor evoked potentials to detect neurological deficit during idiopathic scoliosis correction, estimated the probability of a postoperative neurological deficit with a positive TcMEP change as 26.3%. In clinical practise when an alert is raised based on INM, the clinical team intervenes to try and reduce the risk of adverse events.…”

Clinical outcomes of posterior pedicle screw instrumentation without osteotomy in the management of adolescent idiopathic scoliosis

“…With its assistance, the incidence of neurologic injury has declined. [ 14 , 15 ] As the sensitivity was 100% and specificity was 93% to 100% for transcranial electric motor evoked potentials, the neurological injury rate was 0% for AIS cases, and it was significantly lower than that in previous studies. [ 15 ] However, only a certain number of hospital in China have intraoperative neural electrophysiological monitoring.…”

Loss of intraoperative neurological monitoring signals during flexed prone positioning on a hinged open frame during surgery for kyphoscoliosis correction: case report

“…Although false-negative results with IONM have been reported to occur in surgery for spinal deformity, they are exceedingly rare, and IONM remains highly sensitive and specific in the detection of impending intraoperative neurological insults. 17,21 In cases of severe spinal deformities or patients with multiple previous spinal operations, loss of signals is potentially the result of vascular stretching and/or kinking that occurs along with significant intraoperative alterations to spinal alignment. This may affect blood flow at different points of the spinal canal and branches of spinal arteries and their perforators, resulting in focal ischemia.…”

“…3,12,13 Recent studies in large groups of patients have demonstrated the accuracy of intraoperative neural monitoring (IONM) in detecting intraoperative neurophysiological alterations and suggested its utility in preventing subsequent postoperative clinical neurological deficits. 1,8,14,18,20,21 Multiple monitoring modalities, such as motor evoked potential (MEP), somatosensory evoked potential (SSEP), and both triggered and free-running electromyography (EMG) monitoring, are nearly universally used in surgery for ASD.Prone positioning of patients for ASD surgery, although often overlooked, can be a significant source of complications. 5,6,10,22 Most of the described prone positioning-related complications are related to myocutaneous and/or vascular compression over sustained periods during the intraoperative period (i.e., pressure sores, limb ischemia, etc.).…”