Neurophysiologic Intraoperative Monitoring of Scoliosis Surgery

Intraoperative Monitoring of Scoliosis Surgery in Young Patients

SUMMARY

Intraoperative neurophysiologic monitoring has added substantially to the safety of spinal deformity surgery correction since its introduction over four decades ago. Monitoring routinely includes both somatosensory evoked potentials and motor evoked potentials. Either modality alone will detect almost all instances of spinal cord injury during deformity correction. The combined use of the two modalities provides complementary information, can permit more rapidly identification of problems, and enhances safety though parallel redundancy should one modality fail. Both techniques are well established and continue to be refined. Although there is room for provider preference, proper monitoring requires attention to technical detail, understanding of the underlying physiology, and familiarity with effects of commonly used anesthetic agents.

Updated review on the use of neuromuscular blockade during intraoperative motor-evoked potential monitoring in the modern anesthesia era

Transcranial electrical stimulation motor-evoked potentials (Tc-MEP) monitoring is a common practice in neurosurgery to prevent postoperative neurological damage. However, the use of neuromuscular blocking agents (NMBAs) during Tc-MEP monitoring is a subject of controversy. In addition, the effectiveness of sugammadex, a selective reversal agent, in the context of Tc-MEP monitoring requires further investigation. This review aimed to clarify the considerations involved in achieving optimal Tc-MEP monitoring while ensuring patient safety. Preoperative patient selection, comorbidity assessment, motor power evaluation, and the nature of the planned surgery are critical factors. Accurate paralysis assessment, continuous NMBA infusion, and post-tetanic stimulation techniques are essential for achieving optimal partial NMB. The decision to administer an NMB during Tc-MEP monitoring necessitates a careful evaluation of the balance between accuracy and potential complications. This review emphasizes the challenges associated with NMB administration during Tc-MEP monitoring and highlights the need for personalized patient assessment.

Effect of Sugammadex During Transcranial Electrical Motor Evoked Potentials Monitoring in Spinal Surgery: A Randomized Controlled Trial

INTRODUCTION

Neuromuscular blockade suppresses transcranial electrical motor evoked potential (TceMEP) amplitude and is usually avoided during TceMEP monitoring. In this randomized controlled trial, we investigated whether rocuronium-induced suppression of TceMEP amplitude could be reversed by sugammadex in patients undergoing spine surgery.

METHODS

Seventy-six patients undergoing spinal surgery were randomly allocated into sugammadex and control groups. In the sugammadex group, a rocuronium infusion was titrated to maintain moderate neuromuscular blockade (2 twitches on train-of-four) until dural opening when the rocuronium infusion was discontinued and 2 mg/kg sugammadex administered. In the control group, no neuromuscular blockade was administered after induction of anesthesia. The primary outcome was a comparison between sugammadex and control groups of mean TceMEP amplitudes in the abductor pollicis brevis muscles of both upper extremities 5 minutes after dural. Secondary outcomes included TceMEP amplitudes at 10, 20, 30, and 60 minutes after dural opening.

RESULTS

Sixty-six patients were included in the analysis. TceMEP amplitudes were significantly greater in the sugammadex group (629 μV, interquartile range: 987 μV) than in the control group (502 μV, interquartile range: 577 μV; P =0.033) at 5 minutes after dural opening. TceMEP amplitudes were also greater in the sugammadex group at 10 minutes ( P =0.0010), 20 minutes ( P =0.003), 30 minutes ( P =0.001), and 60 minutes ( P =0.003) after dural opening.

CONCLUSIONS

Moderate neuromuscular blockade induced by continuous infusion of rocuronium was effectively reversed by sugammadex. This suggests that sugammadex could be used to enhance TceMEP waveform monitoring during spine surgery requiring muscle relaxation.

Hemodynamic Consideration in Intraoperative Neurophysiological Monitoring in Neuromuscular Scoliosis Surgery

OBJECTIVE

To prove the hypothesis that the parameters of intraoperative neurophysiological monitoring (IONM) during will be more deteriorated in neuromuscular scoliosis (NMS) than in adolescent idiopathic scoliosis (AIS).

METHODS

This retrospective study reviewed the data of 69 patients (NMS=32, AIS=37) who underwent scoliosis surgery under IONM. The amplitude of motor evoked potentials (MEPs), and the amplitude and the latency of somatosensory evoked potentials (SEPs) were examined. Demographic, preoperative, perioperative and postoperative data were analyzed to determine whether they affected the IONM parameters for each group.

RESULTS

Of the items analyzed, the bleeding amount was the only significant risk factor for SEP latency deterioration in the NMS group only. The amplitude of SEP and MEP did not correlate with the hemodynamic parameters. The NMS/AIS ratios of the bleeding-related parameters were higher in the order of bleeding amount/weight (2.62, p<0.01), bleeding amount/body mass index (2.13, p<0.01), and bleeding amount (1.56, p<0.01). This study suggests that SEP latency is more vulnerable than SEP or MEP amplitude in ischemic conditions during scoliosis surgery.

CONCLUSION

In NMS patients, it should be considered that the bleeding amount can have a critical effect on intraoperative electrophysiological deterioration.

Asymmetrical thoracic-lumbar coordination during trunk rotation between adolescents with and without thoracic idiopathic scoliosis

STUDY DESIGN

Cross-sectional comparative study.

PURPOSE

To compare thoracic-lumbar kinematic changes and coordination based on coupling angles (CAs) in two different directions of trunk rotation between adolescents with idiopathic scoliosis (AIS) and control subjects. Altered three-dimensional (3D) deviations are often apparent in AIS groups during functional activities, such as gait. However, there is a lack of consistent evidence on coordinated motions during different directions of trunk rotation.

METHODS

This study included 14 AIS and 17 age-matched control subjects who were all right limb dominant. A motion capture system was utilized to analyze the spinal segment motions. The outcome measures included range of motion (ROM) at the first thoracic (T1), seventh thoracic (T7), and first lumbar (L1) spinous processes as well as the sacral tubercle (S1). The CAs compared in-phase (rotation from right to left) and anti-phase (rotation from left to right) trunk rotations.

RESULTS

Although there was no significant association with the spinal segments in the control group, the Cobb angle demonstrated significant positive correlations with anti-phase at T7 and L1 as well as in-phase at L1. Regarding the CAs, the groups demonstrated a significant interaction with both phases (F = 4.7, p = 0.04). The AIS group demonstrated positive correlations with ROM during in-phase at L1 and anti-phase at T7 and L1.

CONCLUSION

The coordination based on the CAs of the lumbar spine relative to the thoracic spine significantly decreased during left to right trunk rotation in the AIS group. These results indicated that the AIS group demonstrated directional dissociation toward the dominant side of lumbar rotation.

LEVEL OF EVIDENCE

III.

Effect of intraoperative muscle relaxation reversal on the success rate of motor-evoked potential recording in patients undergoing spinal surgery: study protocol for a randomised controlled trial

INTRODUCTION

Transcranial motor-evoked potentials (TceMEPs) is conventionally performed without neuromuscular blockade (NMB) because of its potential interference with neuromuscular junction and signal interpretation. Sugammadex is the first highly selective antagonist that binds to rocuronium and can rapidly and effectively reverse NMB. This study aims to evaluate the success rate of intraoperative muscle relax reversal by sugammadex on intraoperative TceMEP recording.

METHODS AND ANALYSIS

We will conduct a single-centre randomised controlled study. In total, 162 patients undergoing thoracic or lumbar spinal surgery will be randomly divided into the sugammadex group or control group at a ratio of 1:1. Total intravenous anaesthesia by propofol and remifentanil will be performed in both groups. In the sugammadex group, patients will receive continuous infusion of rocuronium to produce a blockade maintained for at least two twitches in train-of-four, rocuronium infusion will be discontinued and 2 mg/kg sugammadex will be given while performing TceMEPs monitoring. In the control group, rocuronium infusion will be discontinued and the same volume of saline will be infused while performing TceMEPs monitoring. The primary aim of this study is to evaluate the success rate of TceMEPs recording between two groups.

ETHICS AND DISSEMINATION

The approval for the study was certificated by the Ethical Committee of Beijing Tiantan Hospital, Capital Medical University on, 16 July 2021 (KY2021-082-02). The study was registered on clincaltrials.gov on 25 October 2020. Our study might guide neuromuscular blockade plans in TceMEPs monitoring undergoing spinal surgery. The findings of the study will be published in peer-reviewed journals and will be presented at national or international conference.

TRIAL REGISTRATION NUMBER

NCT04608682.

Is routine intraoperative neuromonitoring necessary in growing rod lengthening procedures? A retrospective, observational study

PURPOSE

To investigate whether intraoperative neuromonitoring (IONM) may be avoided in growing rod lengthening procedures in early onset scoliosis (EOS).

METHODS

A total of 636 primary growing rod surgeries and lengthening procedures were performed in 112 patients with EOS. Traditional growing rods (TGR) or magnetically controlled growing rods (MCGR) were implanted and subsequent lengthening procedures were done at stipulated intervals. Combined multi-modality IONM was used in all index surgeries-but was only used in lengthening procedures in patients with existing spinal cord abnormality or a history of neurosurgical procedure for the same, patients with prior history of a neuromonitoring alert in their index surgery and when lengthening was accompanied by an implant exchange/revision. All the remaining growing rod lengthening procedures were carried out without IONM. Hospital records and operation notes were retrospectively reviewed with focus on details of neurological events/complications.

RESULTS

In 112 primary growing rod applications (TGR = 96, MCGR = 16) and 524 lengthening procedures (TGR = 444, MCGR = 80), intraoperative neuromonitoring 'alerts' were encountered in 6/112 index surgeries and temporary postoperative neurological deficits were seen in 2/112 index surgeries. No intraoperative neuromonitoring event or postoperative neurological complication was encountered in 524 lengthening procedures-irrespective of whether they were carried out along with implant exchange, or in patients with spinal cord abnormality or prior neuromonitoring event during index surgery.

CONCLUSION

While IONM should be used in primary growing rod application surgeries, its use may be avoided in lengthening and implant exchange procedures in a resource-limited setting.

LEVEL OF EVIDENCE

Level 3.

A Retrospective Study of Surgical Correction for Spinal Deformity with and without Osteotomy to Compare Outcome Using Intraoperative Neurophysiological Monitoring with Evoked Potentials

BACKGROUND This study aimed to evaluate the effects of different combined evoked potentials monitoring modes for non-osteotomy and osteotomy surgery of spinal deformity, and to select individualized modes for various surgeries. MATERIAL AND METHODS We retrospectively reviewed a total of 188 consecutive cases undergoing spinal deformity correction. All patients were classified into 2 cohorts: non-osteotomy (Group A) and osteotomy (Group B). According to intraoperative evoked potential monitoring mode, Group A was divided into 2 sub-groups: A1 [spinal somatosensory evoked potential (SSEP)/motor evoked potential (MEP), n=67)] and A2 [SSEP/MEP/descending neurogenic evoked potential (DNEP), n=52]. Group B was classified as B1 (SSEP/MEP, n=27) and B2 (SSEP/MEP/DNEP, n=42). The demographics, surgical parameters, and evoked potential events of different combined monitoring modes were analyzed within each group. RESULTS The baselines of SSEP/MEP/DNEP in all cases were elicited successfully. Three cases with evoked potential (EP) events (2 with MEP changes and 1 with SSEP/MEP change) were noted in Group A1 and 1 with SSEP change in Group A2, with no neurological complications. Thirteen cases in Group B1 were positive for MEP intraoperatively, including 16 EP events (13 with MEP change and 3 with both SSEP+MEP changes), with no neural complications. In Group B2, 15 cases had 21 EP events, including 12 with MEP change and 2 with SSEP+MEP changes, with no complications. Postoperative neurological complications were observed in 5 of the 7 cases with SS4EP/DNEP changes. CONCLUSIONS Intraoperative simultaneous SSEP/MEP can effectively reflect neurological function in non-osteotomy spinal surgery patients. Simultaneous SSEP/MEP/DNEP can effectively avoid the unnecessary interference by false-positive results of MEP during osteotomy.

Comparing the effect between continuous infusion and intermittent bolus of rocuronium for intraoperative neurophysiologic monitoring of neurointervention under general anesthesia

BACKGROUND

Medical researchers have been reluctant to use neuromuscular blocking drugs (NMBD) during the use of intraoperative motor evoked potential (MEP) monitoring despite the possibility of patient movement. In this study, we compared the effects of no NMBD and continuous rocuronium infusion on the incidence of patient involuntary movement and MEP monitoring.

METHODS

In this study, 80 patients who underwent neuro intervention with MEP monitoring were randomly assigned into 2 groups. After an anesthetic induction, bolus of rocuronium 0.1 mg/kg was injected when it was needed (for patient involuntary movement or at the request of the surgeon) in group B, and 5 mcg/kg/min of rocuronium were infused in group I study participants. The incidence of patient involuntary movement and spontaneous respiration, the mean MEP amplitude, coefficient of variation (CV), the incidence of MEP stimulus change and train-of-four (TOF) count were compared.

RESULTS

The incidence of involuntary movement and spontaneous movement were measured as significantly lower in group I (P < .05). The incidence of undetectable MEP did not differ as measured in both groups. The means and CVs of MEP amplitude in all limbs were significantly lower in group I. The mean TOF counts from 30 to 80 min of operation were significantly higher in group B.

CONCLUSION

We conclude that the continuous infusion of rocuronium effectively inhibited the involuntary movement and spontaneous respiration of the patient while enabling MEP monitoring.

Transcranial Motor Evoked Potentials during Spinal Deformity Corrections-Safety, Efficacy, Limitations, and the Role of a Checklist

Introduction

Intraoperative neuromonitoring (IONM) has become a standard of care in spinal deformity surgeries to minimize the incidence of new onset neurological deficit. Stagnara wake up test and ankle clonus test are the oldest techniques described for spinal cord monitoring, but they cannot be solely relied upon as a neuromonitoring modality. Somatosensory evoked potentials monitor only dorsal tracts and give high false positive and negative alerts. Transcranial motor evoked potentials (TcMEPs) monitor the more useful motor pathways. The purpose of our study was to report the safety, efficacy, limitations of TcMEPs in spine deformity surgeries, and the role of a checklist.

Study design

Retrospective review of all spinal deformity surgeries performed with TcMEPs from 2011 to 2015.

Materials and methods

All patients were subjected to IONM by TcMEPs during the spinal deformity surgery. Patients were included in the study only if complete operative reports and neuromonitoring data and postoperative neurological data were available for review. An alert was defined as 80% or more decrement in the motor evoked potential amplitude, or increase in threshold of 100 V or more from baseline. The systemic and surgical causes of IONM alerts and the postoperative neurological status were recorded.

Results

In total, 61 patients underwent surgery for spinal deformities with TcMEPs. The average age was 12.6 years (6–36 years) and male:female ratio was 1:1.3. Diagnoses included idiopathic scoliosis (n = 35), congenital scoliosis (n = 13), congenital kyphosis (n = 7), congenital kyphoscoliosis (n = 4), post-infectious kyphosis (n = 1), and post-traumatic kyphosis (n = 1). The average kyphosis was 72° (45°–101°) and the average scoliosis was 84° (62°–128°). There were in total 33 alerts in 22 patients (36%). The most common causes were hypotension (n = 7), drug induced (n = 5), deformity correction (n = 5), osteotomies (n = 3), tachycardia (n = 1), screw placement (n = 2), and electrodes disconnection (n = 1). Reversal of the inciting event cause resulted in complete reversal of the alert in 90% of the times. Three patients showed persistent alerts, out of whom one had a positive wake up test and woke up with neurodeficit, which recovered over few weeks, while the other patients showed persistent alerts but woke up without any deficit. Sensitivity and specificity of TcMEP in deformity correction surgery were 100 and 96.6%, respectively, in our study.

Conclusion

IONM alerts are frequent during spinal deformity surgery. In our study, more than 50% of the alerts were associated with anesthetic management. IONM with TcMEPs is a safe and effective monitoring technique and wake up test still remains a valuable tool in cases of a persistent alert.

Neuromonitoring for scoliosis surgery

The use of intraoperative neuromonitoring (IONM) during pediatric scoliosis repair has become commonplace to reduce the risk of potentially devastating postoperative neurologic deficits. IONM techniques include somatosensory evoked potentials, motor evoked potentials, electromyography, and intraoperative wake-up tests. Special considerations for scoliosis repair in pediatric patients include preexisting neurologic deficits and young patients with immature neural pathways in whom neurophysiologic monitoring may prove difficult or unreliable.

Non-neurologic complications following surgery for scoliosis

BACKGROUND

The purpose of this study was to determine the prevalence of non-neurologic complications following surgery for scoliosis and to identify factors that can increase this risk.

METHODS

The demographic data, medical and surgical histories, and prevalence of non-neurologic complications were reviewed in a retrospective cohort of 602 patients, who had undergone corrective surgery for scoliosis between January 2001 and June 2011.

RESULTS

There were 450 patients under 20 years old (U20) and 152 of patients above 20 years old (A20) enrolled in this study. Forty-nine patients in U20 (10.9%) and 18 patients in A20 (11.8%) had post-operative complications. Respiratory complications were most common in U20 (4%) and gastrointestinal complications were most common in A20 (7%). There was no significant difference between the 2 groups in the prevalence of complications. Logistic regression revealed that factors that correlated with an increased odds for complications were Cobb angle (P = 0.001/P = 0.013, respectively), length of operation time (P = 0.003/P = 0.006, respectively), duration of anesthesia (P < 0.001/P = 0.005, respectively) and transfusion (P = 0.003/P = 0.015, respectively) in U20 and A20. Also, comorbidities (P = 0.021) in U20, and decreased body mass index (P = 0.030), pre-operative forced vital capacity (P = 0.001), forced expired volume in 1s (P = 0.001), increased numbers of vertebrae fused (P = 0.004), blood loss (P = 0.001) in A20 were associated with increased odds for complications.

CONCLUSIONS

There was no difference in the prevalence of complication in scoliosis patients by age. The prevalence of complication was dependent on Cobb angle, length of operation time, duration of anesthesia and transfusion of PRBC. Deterioration of preoperative pulmonary function significantly increased risk of post-operative complications in adult patients.

The usefulness of intraoperative neurophysiological monitoring in cervical spine surgery: a retrospective analysis of 200 consecutive patients

The usefulness of intraoperative neurophysiological monitoring (IONM), including somatosensory-evoked potential (SSEP) and transcranial electrical motor-evoked potentials (TcMEPs) in cervical spine surgery still needs to be evaluated. We retrospectively reviewed 200 cervical spine surgery patients from 2008 to 2009 to determine the role of IONM in cervical spine surgery. Total intravenous anesthesia was used for all patients. IONM alerts were defined as a 50% decrease in amplitude, a 10% increase in latency, or a unilateral change for SSEP and an increase in stimulation threshold of more than 100 V for TcMEP. Three patients had SSEP alerts that were related to arm malposition (2 patients) and hypotension (1 patient). Five patients had TcMEP alerts: 4 alerts were caused by hypotension and 1 by bone graft compression of the spinal cord. All alerts were resolved when causative reasons were corrected. There was no postoperative iatrogenic neurological injury. The sensitivities of SSEP and TcMEP alerts for detecting impending neurological injury were 37.5% and 62.5%, respectively. The sensitivity of both SSEP and TcMEP used in combination was 100%. No false-positive and false-negative alerts were identified in either SSEP or TcMEP (100% specificity). The total intravenous anesthesia technique optimizes the detection of SSEP and TcMEP and therefore improves the sensitivity and specificity of IONM. SSEP is sensitive in detecting alerts in possible malposition-induced ischemia or brachial plexus nerve injury. TcMEP specifically detects hypotension-induced spinal functional compromises. Combination use of TcMEP and SSEP enhances the early detection of impeding neurological damage during cervical spine surgery.

Warning thresholds on the basis of origin of amplitude changes in transcranial electrical motor-evoked potential monitoring for cervical compression myelopathy

STUDY DESIGN

A retrospective analysis of prospectively collected data from consecutive patients undergoing transcranial electrical motor-evoked potential (TCE-MEP: compound muscle action potentials) monitoring during cervical spine surgery. OBJECTIVE.: To divide the warning threshold of TCE-MEP amplitude changes on the basis of origin into the spinal tract and spinal segments and decide warning thresholds for each.

SUMMARY OF BACKGROUND DATA

The parameter commonly used for the warning threshold in TCE-MEP monitoring is wave amplitude, but amplitude changes have not been examined by anatomical origin.

METHODS

Intraoperative TCE-MEP amplitude changes were reviewed for 357 patients with cervical myelopathy. Most of the patients were monitored by transcranial electrical stimulated spinal-evoked potential combined with TCE-MEP. The warning threshold of TCE-MEP was taken as waveform disappearance. For each patient, amplitude changes were separated, according to origin, into the spinal tract and spinal segments and compared with clinical outcome.

RESULTS

Assessable TCE-MEP waves were obtained in 350 cases. Disappearance of TCE-MEP waves, which were innervated by the spinal levels exposed to the surgical invasion, was seen in 11 cases. Disappearance of TCE-MEPs, which were innervated by the spinal levels inferior to them, was seen in 43 cases. There was no postoperative motor deficit in those cases. However, such deficits caused by spinal segment injury were seen in 2 cases, which showed that intraoperative amplitude decreased to 4.5% and 27%.

CONCLUSION

If we had established the warning threshold as 30% of the control amplitude, we would likely have prevented both cases of postoperative motor deficits, but 106 (30.3%) cases would have become positive cases. If we had established the warning threshold separately as wave disappearance for the spinal tract and 30% of the control amplitude for the spinal segments, sensitivity and specificity would have been 100% and 83.7%, respectively. Dividing the warning threshold on the basis of origin of amplitude changes could reduce false-positive cases and prevent intraoperative injuries.

Intraoperative monitoring in pediatric orthopedic spinal surgery: three hundred consecutive monitoring cases of which 10% of patients were younger than 4 years of age

STUDY DESIGN

Analysis of a prospective series of 300 consecutive cases undergoing intraoperative monitoring in pediatric orthopedic spinal surgery, of which 10% were children younger than 4 years.

OBJECTIVE

Determine feasibility and performance of intraoperative monitoring in children younger than 4 years. Analyze distinct physiopathologic mechanisms of relevant alerts.

SUMMARY OF BACKGROUND DATA

There are few studies in the literature concerning the intraoperative monitoring of children younger than 4 years. During childhood, the development of sensori-motor pathways is dominated by two coexisting phenomena, which have opposite effects: maturation decreasing latencies and height increasing them.

METHODS

We used intraoperative somatosensory-evoked potentials and neurogenic mixed evoked potentials with a flexible bipolar epidural electrode. Uniform total intravenous anesthesia was used.

RESULTS

Values of sensitivity and specificity of the monitoring showed slight differences between patients younger than 4 years versus older patients. There was no false-negative outcome. Various tendencies were highlighted. There were more true positive alerts for secondary etiologies than for idiopathic ones, for revision spinal surgeries than for index ones, and for boys than for girls. There were no more true positive alerts for children younger than 4 years than for older patients whereas the proportion of hemivertebrae was obviously greater for the younger group. Relevant monitoring alerts were more frequent in case of kyphoscoliosis. This is highlighted in case reports.

CONCLUSION

In some cases of kyphoscoliosis, during a posterior-based vertebral column resection, monitoring changes were corrected by positioning a rod that allowed correction of the position of the spine in the sagittal plane. Intraoperative spinal cord monitoring can be performed in children younger than 4 years and allows real-time assessment of spinal functional integrity.

Intraoperative electrophysiological monitoring in spine surgery

STUDY DESIGN

Review of the literature with analysis of pooled data.

OBJECTIVE

To assess common intraoperative neuromonitoring (IOM) changes that occur during the course of spinal surgery, potential causes of change, and determine appropriate responses. Further, there will be discussion of appropriate application of IOM, and medical legal aspects. The structured literature review will answer the following questions: What are the various IOM methods currently available for spinal surgery? What are the sensitivities and specificities of each modality for neural element injury? How are the changes in each modality best interpreted? What is the appropriate response to indicated changes? Recommendations will be made as to the interpretation and appropriate response to IOM changes.

SUMMARY OF BACKGROUND DATA

Total number of abstracts identified and reviewed was 187. Full review was performed on 18 articles.

METHODS

The MEDLINE database was queried using the search terms IOM, spinal surgery, SSEP, wake-up test, MEP, spontaneous and triggered electromyography alone and in various combinations. Abstracts were identified and reviewed. Individual case reports were excluded. Detailed information and data from appropriate articles were assessed and compiled.

RESULTS

Ability to achieve IOM baseline data varied from 70% to 98% for somatosensory-evoked potentials (SSEP) and 66% to 100% for motor-evoked potentials (MEP) in absence of neural axis abnormality. Multimodality intraoperative neuromonitoring (MIOM) provided false negatives in 0% to 0.79% of cases, whereas isolated SSEP monitoring alone provided false negative in 0.063% to 2.7% of cases. MIOM provided false positive warning in 0.6% to 1.38% of cases.

CONCLUSION

As spine surgery, and patient comorbidity, becomes increasingly complex, IOM permits more aggressive deformity correction and tumor resection. Combination of SSEP and MEP monitoring provides assessment of entire spinal cord functionality in real time. Spontaneous and triggered electromyography add assessment of nerve roots. The wake-up test can continue to serve as a supplement when needed. MIOM may prove useful in preservation of neurologic function where an alteration of approach is possible. IOM is a valuable tool for optimization of outcome in complex spinal surgery.

Intraoperative neuromonitoring in pediatric spinal deformity surgery

Pediatric spinal deformity includes a broad range of disorders with differing causes, natural histories, and treatments. Spinal deformity surgery is performed to arrest the progression of and correct coronal and sagittal plane deformities including scoliosis and kyphosis. It is also undertaken to improve cosmesis and decrease the pain that can be associated with certain types of spinal deformity. Iatrogenic spinal cord injury remains the most feared complication of corrective spine surgery. Intraoperative neuromonitoring may be the single innovation that has had the greatest impact in lowering neurological complication rates over the last 2 decades. It is currently recommended in pediatric spinal deformity surgery whenever cord-level spinal instrumentation is planned and reliable signals can be anticipated. This article will briefly discuss common types of pediatric spinal deformity and corrective spine surgery. The use of intraoperative neuromonitoring in pediatric spine surgery will also be reviewed. As our abilities to correct more complex spinal deformities continue to improve, the importance of more advanced methods to decrease the risk of intraoperative neurological complications will also continue to increase.