• free-run and triggered electromyography
• intraoperative neuromonitoring
• lumbar fusion
• patient safety
• postoperative neurologic deficits
• somatosensory evoked potentials

• Effectiveness
• Halo-pelvic traction
• Posterior spinal fusion
• Safety
• Spinal deformity

• Humans
• Spinal Fusion/methods
• Spinal Fusion/adverse effects
• Traction/methods
• Traction/adverse effects
• Female
• Male
• Prospective Studies
• Adult
• Treatment Outcome
• Young Adult
• Adolescent
• Spinal Curvatures/surgery
• Postoperative Complications/epidemiology
• Postoperative Complications/etiology
• Middle Aged
• Cohort Studies
• Severity of Illness Index

• cervical
• level 1
• mJOA
• mean arterial pressure
• myelopathy

• Electromyography
• Intraoperative electrophysiological monitoring
• Neurogenic motor evoked potential
• Neurological deficits
• Scoliosis
• Sensitivity analysis
• Somatosensory evoked potential
• Transcranial motor evoked potential

• Humans
• Scoliosis/surgery
• Scoliosis/mortality
• Retrospective Studies
• Female
• Male
• Postoperative Complications/diagnosis
• Postoperative Complications/epidemiology
• Postoperative Complications/etiology
• Intraoperative Neurophysiological Monitoring/methods
• Adolescent
• Databases, Factual
• Evoked Potentials, Motor
• Child
• Adult
• Young Adult
• Monitoring, Intraoperative/methods
• Sensitivity and Specificity
• Spinal Fusion/adverse effects

• Adolescent idiopathic scoliosis
• alert
• deformity correction
• intraoperative neurophysiologic monitoring
• percentage of correction
• spinal cord injury
• staged operation

• Idiopathic scoliosis
• Intraoperative neuromonitoring (IONM)
• Neurophysiological monitoring
• Scoliosis correction
• Somatosensory evoked potential (SSEP)

• Humans
• Child
• Young Adult
• Adult
• Scoliosis/diagnosis
• Scoliosis/surgery
• Evoked Potentials, Somatosensory/physiology
• Monitoring, Intraoperative
• Orthopedic Procedures
• Neurosurgical Procedures
• Intraoperative Neurophysiological Monitoring
• Evoked Potentials, Motor/physiology
• Retrospective Studies

• care pathways
• checklists
• guidelines
• intraoperative spinal cord injury

• Western Economic Diversification Canada
• AO Foundation
• Praxis Spinal Cord Institute

• Descending neurogenic-evoked potentials
• Intraoperative spinal cord monitoring
• Motor-evoked potentials
• Pediatric spinal deformity
• Spinal deformity surgery

• cerebellopontine angle
• free-run emg
• multimodal
• neurological deficits
• neuromonitoring
• neurophysiological
• post-operative
• somatosensory evoked potentials
• surgeries
• transcranial motor evoked potentials

• Cerebral palsy
• Epilepsy
• Neuromuscular scoliosis
• Seizure disorder
• Transcranial electric motor evoked potentials

• Abductor hallucis
• Extensor digitorum brevis
• Intraoperative muscle motor evoked potentials
• Spine surgery
• Tibialis anterior

• Humans
• Monitoring, Intraoperative/methods
• Spinal Cord/surgery
• Spine/surgery
• Muscle, Skeletal/physiology
• Neurosurgical Procedures
• Evoked Potentials, Motor/physiology

Acute spinal subdural haematoma (ASSH) is a rare and potentially devastating condition with a variable prognosis. Previously described subdural haematomas were thought to have occurred spontaneously or be related to major or minor iatrogenic or traumatic injuries caused by surgery, spinal puncture or epidural anaesthesia. Other contributing pathologies have been described, such as intradural tumours or spinal arteriovenous malformations. ASSH has also been associated with anticoagulation therapy, haemostatic abnormalities and risk factors such as pregnancy. To the best of our knowledge, this case study described the first reported occurrence of an ASSH during spinal surgery in a paediatric patient. The patient was not known to have any coagulopathies, and no obvious vascular lesions were documented. The surgical procedure did not directly involve the dura mater, and no evident intraoperative dural tears were found.

We reported and discussed a case of ASSH complicating a posterior spinal instrumented fusion during surgery for paediatric congenital scoliosis. This condition has not been previously described. We made recommendations for facing such an occurrence, explored its aetiology in the context of malformation and discussed the benefits of neuromonitoring during scoliosis correction and the management protocol. We conducted a PubMed literature review for cases of paediatric ASSH and other closely related disorders. We reviewed recommendations regarding neuromonitoring and treatment management in such cases.

ASSH is a rare complication of posterior spinal instrumented fusion. Published cases are more often associated with anticoagulation therapy or coagulopathy. Neuromonitoring is strongly recommended to detect and assess neurological status, thus enabling rapid diagnosis and treatment and facilitating early spinal decompression and a return to a normal neurological status.

• Acute spinal subdural hematoma
• Congenital malformation
• Paediatric
• Posterior spinal instrumented fusion
• Scoliosis
• Somatosensory evoked potential
• Case report

• Acute spinal subdural haematoma
• Case report
• Congenital malformation
• Paediatric
• Posterior spinal instrumented fusion
• Scoliosis
• Somatosensory evoked potential

• Blood loss
• Evoked potentials
• Intraoperative neurophysiological monitoring
• Scoliosis

• Compound muscle action potential
• Deformity surgery
• EMG
• Intraoperative neurophysiological monitoring
• Pedicle breach
• Scoliosis
• Screw test

• Asystole
• Bradycardia
• Intraoperative neuromonitoring
• Motor evoked potentials
• Transcranial electric stimulation

• Cervical Vertebrae/surgery
• Electric Stimulation
• Evoked Potentials, Motor/physiology
• Heart Arrest/epidemiology
• Heart Arrest/etiology
• Humans
• Intraoperative Neurophysiological Monitoring/methods
• Monitoring, Intraoperative/methods
• Retrospective Studies

• Expert consensus
• High-risk
• Intraoperative neuromonitoring
• Neurological deficit
• Prevention
• Spinal deformity

Distraction spinal cord injuries (DSCIs) often occur as the neurological complication of distraction forces following the implantation of internal fixation devices during scoliosis correction surgery. However, the underlying mechanism behind these injuries remains unclear. The present study aimed to explore the activation of microglia and macrophages, as well as changes in TLR4-mediated NF-κB and MAPK pathway activity after DSCIs in Bama miniature pigs. Prior to surgical intervention, the pigs were randomly divided into three groups: the sham group, the complete distraction spinal cord injury (CDSCI) group, and the incomplete distraction spinal cord injury (IDSCI) group. After surgery, the Tarlov scale and individual limb motor scale (ILMS) were used to evaluate changes in the pigs’ behavior. All pigs were euthanized 7 days after surgery, and histopathological examinations of the spinal cord tissues were performed. Immunohistochemistry was used to detect Caspase-3 expression in the anterior horn of spinal gray matter tissues. Immunofluorescence staining was utilized to assess the M1/M2 phenotype changes in microglia/macrophages and NF-κB P65 expression in central DSCI lesions, while western blotting was performed to determine the expression of TLR4/NF-κB/MAPK pathway-related proteins. The results of the present study showed that the Tarlov and ILMS scores decreased significantly in the two DSCI groups compared with the sham group. Hematoxylin and eosin (HE) and Nissl staining revealed that the tissue structure and nerve fiber tracts in the distracted spinal cord tissues were destroyed. Both DSCI groups showed the number of survived neurons decreased and the Caspase-3 expression increased. The results of the immunofluorescence staining indicated that the CD16 and CD206 expression in the microglia/macrophages increased. Between the two DSCI groups, the CDSCI group showed increased CD16 and decreased CD206 expression levels. The intensity of the fluorescence of NF-κB P65 was found to be significantly enhanced in pigs with DSCIs. Moreover, western blot results revealed that the expression of TLR4, p-IκBα, NF-κB P65, p-JNK, p-ERK, and p-P38 proteins increased in spinal cord tissues following DSCI. The present study was based on a porcine DSCI model that closely mimicked clinical DSCIs while clarifying DSCI-associated neuroinflammation mechanisms, in turn providing evidence for identifying potential anti-inflammatory targets.

• TLR4 signaling pathway
• distraction spinal cord injury
• microglia/macrophages
• neuroinflammation
• porcine model

Intraoperative neuromonitoring (IONM) has become an increasingly essential technique in spinal surgery. However, data on the diagnostic value of IONM in predicting impending postoperative neurological deficits (PONDs) for patients who underwent posterior decompression surgery for thoracic spinal stenosis (TSS) are limited. Furthermore, patients who are at the highest risk of waveform changes during the surgery remain unknown. Our purpose was to (1) assess the diagnostic accuracy of IONM by combining somatosensory-evoked potential (SSEP) with motor-evoked potential (MEP) in predicting PONDs for patients who underwent the surgery and (2) identify the independent risk factors correlated with IONM changes in our study population.

A total of 326 consecutive patients who underwent the surgery were identified and analyzed. We collected the following data: (1) demographic and clinical data; (2) IONM data; and (3) outcome data such as details of PONDs, and recovery status (complete, partial, or no recovery) at the 12-month follow-up visit.

In total, 27 patients developed PONDs. However, 15, 6, and 6 patients achieved complete recovery, partial recovery, and no recovery, respectively, at the 12-month follow-up. SSEP or MEP change monitoring yielded better diagnostic efficacy in predicting PONDs as indicated by the increased sensitivity (96.30%) and area under the receiver operating characteristic (ROC) curve (AUC) value (0.91). Only one neurological deficit occurred without waveform changes. On multiple logistic regression analysis, the independent risk factors associated with waveform changes were as follows: preoperative moderate or severe neurological deficits (p = 0.002), operating in the upper- or middle-thoracic spinal level (p = 0.003), estimated blood loss (EBL) ≥ 400 ml (p < 0.001), duration of symptoms ≥ 3 months (p < 0.001), and impairment of gait (p = 0.001).

Somatosensory-evoked potential or MEP change is a highly sensitive and moderately specific indicator for predicting PONDs in posterior decompression surgery for TSS. The independent risks for IONM change were as follows: operated in upper- or middle-thoracic spinal level, presented with gait impairment, had massive blood loss, moderate or severe neurological deficits preoperatively, and had a longer duration of symptoms.

[http://www.chictr.org.cn]; identifier [ChiCTR 200003 2155].

• intraoperative neuromonitoring
• motor-evoked potential
• postoperative neurological deficits
• somatosensory-evoked potential
• thoracic spinal stenosis

• Charcot–Marie–Tooth
• Intraoperative neuromonitoring
• Spinal deformity
• Sweep length
• Transcranial motor-evoked potentials

• Cervical spondylotic myelopathy (CSM)
• case report
• cervical spinal stenosis
• intraoperative neurophysiologic monitoring (IONM)
• transabdominal adrenalectomy

• mini-incision surgery
• operative treatments
• pediatrics
• robotics
• scoliosis
• spine

• Adolescent idiopathic scoliosis
• Complication
• Reoperation
• Unplanned return to OR

Intraoperative neuromonitoring (IONM) is a well-established adjunct to spinal surgery to ensure safety of the neural elements.IONM has extremely high sensitivity and specificity for impending neurologic damage. In very rare instances, hypoperfusion of the cord may lead to a loss of IONM modalities that may be reversed if blood pressure issues responsible for the drop out of potentials are immediately addressed.

The authors describe a case in which IONM documented hypoperfusion of the cord intraoperatively due to hypotension. Recognition of this problem and reversal of the hypotension resulted in normalization of postoperative function.

The use of IONM allowed for quick recognition of an impending neurological insult during spinal deformity surgery. Prompt response to signaling changes allowed for the correction of hypotension and favorable neurologic outcome.

• Hypotension
• Multimodal neuromonitoring
• Neurosurgery
• Spinal deformity surgery
• Spine

• adolescent idiopathic scoliosis
• health care costs
• medical costs
• spinal instrumentation
• spine surgery
• trends

Background and Objectives: Full-endoscopic cervical foraminotomy (FECF) and microendoscopic cervical foraminotomy (MECF) are effective surgeries for cervical radiculopathy and are considered minimally invasive in terms of damage to paraspinal soft tissue. However, no studies have quantitatively compared FECF and MECF in terms of neurological invasiveness. The aim of this study was to compare the neurological invasiveness of FECF and MECF using intraoperative motor evoked potential (MEP) monitoring. Materials and Methods: A chart review was conducted of 224 patients with cervical radiculopathy who underwent FECF or MECF between April 2014 and March 2020. Patients were 37 women and 187 men, with a mean age of 51 (range, 21–86) years. FECF was performed in 143 cases and MECF was performed in 81 cases. Results: Average MEP amplitude significantly increased from 292 mV before to 677 mV after nerve root decompression in patients who underwent the FECF. The average improvement rate was 273%. In patients who underwent the MECF, average MEP amplitude significantly increased from 306 mV before to 432 mV after nerve root decompression. The average improvement rate was 130%. The improvement rate was significantly higher for FECF compared with MECF. Conclusions: MEP amplitude increased after nerve root decompression in both FECF and MECF, but the improvement rate was higher in FECF. These results suggest that FECF might be more minimally invasive than MECF in terms of neurological aspects.

• cervical radiculopathy
• full-endoscopic cervical foraminotomy
• intraoperative motor evoked potential monitoring
• microendoscopic cervical foraminotomy

• deficits
• intraoperative
• monitoring
• morbidity
• neurological
• neurophysiological
• postoperative
• revision
• spine
• surgery

• 3-Column osteotomy
• Acute spinal shortening
• Goat model
• Laminectomy extension
• Somatosensory evoked potential
• Spinal cord injury

• Animals
• Goats
• Laminectomy/adverse effects
• Spinal Cord
• Spinal Cord Injuries/surgery
• Spine/surgery

• 81672232 The National Natural Science Foundation of China

• Contactless
• Electromagnetic induction heating
• Kyphosis
• Nickel titanium (NiTi)
• Scoliosis
• Shape-memory alloy (SMA)

In spine deformity surgery, iatrogenic neurologic injuries might occur due to the mechanical force applied to the spinal cord from implants, instruments, and bony structures, or due to ischemic changes from vessel ligation during exposure and cord distraction/compression during corrective manoeuvres.

Cite this article: EFORT Open Rev 2020;5:9-16. DOI: 10.1302/2058-5241.5.180032

• intraoperative neuromonitoring
• medicolegal issue
• motor potentials
• neurological deficit
• safety
• spinal deformity

• MAP
• intraoperative hypotension
• mean arterial pressure
• secondary cord injury
• trauma
• traumatic spinal cord injury

• EMG
• MEP
• SSEP
• monitoring
• spine surgery

•

Motor threshold can be variable during surgery in TES-MEP.

Motor threshold usually varies in the intraoperative motor evoked potential (MEP) by transcranial evoked stimulation (TES). This study investigated the degree of change in the motor threshold before and after surgery in TES-MEP monitoring with threshold criterion. This study aimed to evaluate the threshold change and discuss the factors influencing the motor threshold.

We retrospectively analyzed TES-MEP monitoring during supratentorial surgery with frontotemporal craniotomy in 72 patients without pre- and postoperative motor weakness. We analyzed the percentage changes between the affected and the unaffected sides, correlating the changes on the two sides.

The percentage change on the affected and the unaffected side was 4.4 ± 15.1% and 0.4 ± 6.5%, respectively. The percentage change on the affected side was significantly larger than that on the unaffected side. A significantly positive correlation between the percentage change on the affected and the unaffected sides was detected.

The threshold for the TES-MEP varied significantly more than that on the unaffected side.

It is important to understand the characteristics of threshold variation for the evaluation of TES-MEP.

• Intraoperative environmental changes
• Motor evoked potential
• Motor threshold
• Threshold change
• Threshold criterion
• Transcranial electrical stimulation

• Brown-Sequard syndrome
• anemia
• anterior cord syndrome
• incomplete spinal cord injuries
• motor evoked potentials
• neuromonitoring
• pediatric
• perfusion
• scoliosis
• transfusion

Intraoperative somatosensory evoked potential (SSEP) and transcranial motor evoked potential (tcMEP) monitoring are frequently used in spinal as well as spinal cord surgery for so-called intraoperative neuromonitoring (IONM), while the combination of these techniques is known as concomitant multimodal intraoperative monitoring (MIOM). The aim of this review is to collect available evidence concerning use of IONM and MIOM in cervical decompression surgery in the degenerative setting and attempt to identify the best practice to be advocated.

A review of the PubMed and MEDLINE databases and Cochrane Central Registry of Controlled Trials was performed. Studies were included if they involved patients who underwent cervical spine decompression surgery for degenerative stenosis with use of IONM or MIOM and where sensitivity/specificity was reported.

In the identified studies, the sensitivity of SSEP was estimated to be between 22 and 100% with constant specificity of 100%. In the included studies, the sensitivity of MEP was estimated to be between 78 and 100% with specificity ranging from 83.2 to 100%.

On the basis of available evidence, MIOM could be a helpful tool in decompression cervical spine surgery in patients affected by degenerative spinal stenosis, since it is associated with high specificity and sensitivity for detection of intraoperative neural damage. However, evidence is still lacking regarding patient selection to identify individuals in whom monitoring is indicated.

IV (systematic review of studies with LOE II to IV).

• Cervical spine surgery
• Evoked potentials
• IONM
• MEP
• SSEP

• motor evoked potential
• neuro-monitoring
• neurologic deficit
• scoliosis

• cerebral aneurysm
• cerebral injury
• evoked potential monitoring
• ischemia
• motor evoked potential
• stroke

• Brain Injuries/diagnosis
• Brain Injuries/etiology
• Evoked Potentials
• Humans
• Intracranial Aneurysm/surgery
• Intraoperative Neurophysiological Monitoring/methods
• Reproducibility of Results

• Hemodynamic stress from radicular injury
• Intraoperative motor evoked potential changes
• Successful discrimination

Intraoperative neuromonitoring using motor evoked potentials (MEP) satisfactorily detects motor tract integrity changes during spinal surgery. However, monitoring is affected by “anesthetic fade,” in which the stimulation threshold increases because the waveform amplitude decreases with the accumulation of propofol. Therefore, the purpose of this study was to clarify the effect of anesthetic fade on transcranial MEPs by investigating the time-dependent changes of amplitude during spinal deformity surgeries.

We retrospectively reviewed medical records of 142 spinal deformity patients (66 patients with idiopathic scoliosis, 28 with adult spinal deformities, 19 with neuromuscular scoliosis, 17 with syndromic scoliosis, and 12 with congenital scoliosis). The average age was 28 years (range, 5 to 81 years). MEPs were recorded bilaterally from the abductor digiti minimi (ADM) and abductor hallucis (AH) muscles during spinal deformity surgeries. The Wilcoxon signed-rank test was used to investigate the time-dependent changes of amplitude after propofol infusion to evaluate anesthetic fade effects.

The average time to baseline from initial propofol infusion was 113 min (range, 45 to 182 min). In the ADM, the amplitude was 52% at 1 h after initial propofol infusion, 102% at 2 h, 105% at 3 h, 101% at 4 h, 86% at 5 h, and 81% at 6 h. Compared to the 2-h time point, MEP decreased significantly by 16% at 5 h (P < 0.0005) and by 21% at 6 h (P < 0.05). In the AH, the amplitude was 49% at 1 h after initial infusion of propofol, 102% at 2 h, 102% at 3 h, 92% at 4 h, 71% at 5 h, and 63% at 6 h. Compared to the 2-h time point, MEP decreased significantly by 10% at 4 h (P < 0.005), by 31% at 5 h (P < 0.0000005), and by 39% at 6 h (P < 0.05).

MEP amplitude significantly decreased in the upper limbs at 5 and 6 h and in the lower limbs at 4, 5, and 6 h after the initial infusion of propofol, respectively. The influence of anesthetic fade could influence false positive MEPs during long spinal surgeries.

• Abductor digiti minimi
• Abductor hallucis
• Alarm point
• Amplitude
• Anesthetic fade
• False positive
• Intraoperative neuromonitoring
• Motor evoked potential
• Propofol
• Spinal deformity surgery

• Adolescent idiopathic scoliosis (AIS)
• neuromonitoring
• pedicle screw fixation
• robotic-assistance
• triggered screw electromyography (t-EMG)

Cervical compressive myelopathy (CCM) is a progressive, degenerative spine disease and the most common cause of spinal cord dysfunction in older individuals. Current clinical guidelines for spinal surgery recommend multimodal intraoperative monitoring (IOM) during spinal surgery as a reliable and valid diagnostic adjunct to assess spinal cord integrity. The aim of this study was to evaluate the effect of positive changes during IOM on the functional status in patients with CCM.

Patients who underwent spinal surgery with IOM due to CCM were enrolled. During the surgery, patients underwent IOM using motor evoked potential (MEP) and somatosensory evoked potential (SEP). MEP and SEP were checked before and immediately after decompression. A decrease in latency >10% or an increase in amplitude >50% was regarded as a “positive changes”. Subjects were divided according to the presence of positive changes. Motor scores of American Spinal Injury Association (ASIA) impairment scale and Korean version of Modified Barthel Index (K-MBI) were evaluated before and after operation.

Twenty-nine patients underwent spinal surgery due to CCM. Eleven patients showed positive changes in MEP during IOM. When the two groups were compared, improvement rate in the ASIA motor score and K-MBI were significantly higher in patients with positive changes than in patients without positive changes at 1 month after surgery. However, 6 months after surgery, there were no significance differences between the groups. Regardless of positive change, nearly all patients suffered from neuropathic pain after operation.

Positive changes in MEP during IOM may affect functional improvement 1 month after operation and early discharge without significant complications in CCM patients. However, they do not affect the neuropathic pain and long-term functional outcome. Thus, tailored proper management is needed to achieve maximal functional recovery in each patient after cervical spinal decompression surgery.

• cervical myelopathy
• degenerative disorder
• function
• intraoperative monitoring
• positive change

• Lumbar spinal stenosis (LSS)
• clinical outcome
• decompression surgery
• intra-operative neurophysiological monitoring

• EMG
• MEP
• PSO
• SSEP
• VCR
• neuromonitoring
• spinal deformity
• spine surgery