Impact of Perioperative Neurologic Deficits on Clinical Outcomes After Posterior Cervical Fusion

Transcranial Motor Evoked Potentials as a Predictive Modality for Postoperative Deficit in Cervical Spine Decompression Surgery - A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic Review and Meta-analysis.

OBJECTIVE

The purpose of this study was to evaluate whether transcranial motor evoked potential (TcMEP) alarms can predict postoperative neurologic complications in patients undergoing cervical spine decompression surgery.

METHODS

A meta-analysis of the literature was performed using PubMed, Web of Science, and Embase to retrieve published reports on intraoperative TcMEP monitoring for patients undergoing cervical spine decompression surgery. The sensitivity, specificity, and diagnostic odds ratio (DOR), of overall, reversible, and irreversible TcMEP changes for predicting postoperative neurological deficit were calculated. A subgroup analysis was performed to compare anterior vs posterior approaches.

RESULTS

Nineteen studies consisting of 4608 patients were analyzed. The overall incidence of postoperative neurological deficits was 2.58% (119/4608). Overall TcMEP changes had a sensitivity of 56%, specificity of 94%, and DOR of 19.26 for predicting deficit. Reversible and irreversible changes had sensitivities of 16% and 49%, specificities of 95% and 98%, and DORs of 3.54 and 71.74, respectively. In anterior procedures, TcMEP changes had a DOR of 17.57, sensitivity of 49%, and specificity of 94%. In posterior procedures, TcMEP changes had a DOR of 21.01, sensitivity of 55%, and specificity of 94%.

CONCLUSION

TcMEP monitoring has high specificity but low sensitivity for predicting postoperative neurological deficit in cervical spine decompression surgery. Patients with new postoperative neurological deficits were 19 times more likely to have experienced intraoperative TcMEP changes than those without new deficits, with irreversible TcMEP changes indicating a much higher risk of deficit than reversible TcMEP changes.

Neurologic Complications in the Postoperative Neurosurgery Patient

PURPOSE OF REVIEW

This article discusses neurologic complications encountered in the postoperative care of neurosurgical patients that are common or key to recognize in the immediate postoperative period. The major neurosurgical subspecialty procedures (cerebrovascular neurosurgery, neuro-oncology, epilepsy neurosurgery, functional neurosurgery, CSF diversion, endovascular neurosurgery, and spinal surgery) are broadly included under craniotomy procedures, endovascular/vascular procedures, and spinal procedures. This article focuses on the range of complications inherent in these approaches with specific scenarios addressed as applicable.

RECENT FINDINGS

The morbidity and mortality related to neurosurgical procedures remains high, necessitating ongoing research and quality improvement efforts in perioperative screening, intraoperative management, surgical approaches, and postoperative care of these patients. Emerging research continues to investigate safer and newer options for routine neurosurgical approaches, such as coiling over clipping for amenable aneurysms, endoscopic techniques for transsphenoidal hypophysectomy, and minimally invasive spinal procedures; postoperative monitoring and care of patients after these procedures continues to be a key component in the continuum of care for improving outcomes.

SUMMARY

Postoperative care of patients undergoing major neurosurgical procedures is an integral part of many neurocritical care practices. Neurosurgeons often enlist help from neurologists to assist with evaluation, interpretation, and management of complications in routine inpatient settings. Awareness of the common neurologic complications of various neurosurgical procedures can help guide appropriate clinical monitoring algorithms and quality improvement processes for timely evaluation and management of these patients.

Spinal surgery for a late-onset axial myopathy

Axial myopathies with paraspinal predominance usually present with dropped head, abnormal posture or rigidity of the spine. Management of axial myopathy can be difficult and there is little data in the literature about surgical treatment. We discuss a case of axial myopathy with late-onset scoliosis and dropped head, focusing on the surgical management of the case.

Complications following posterior cervical decompression and fusion: a review of incidence, risk factors, and prevention strategies

Posterior cervical decompression and fusion (PCF) is a common surgical technique used to treat various cervical spine pathologies. However, there are various complications associated with PCF that can negatively impact patient outcome. We performed a comprehensive literature review to identify the most common complications following PCF using PubMed, Cochrane Database of Systematic Reviews, and Google Scholar. The overall complication rates of PCF are estimated to range from about 15% to 25% in the current literature. The most common immediate complications include acute blood loss anemia, surgical site infection (SSI), C5 palsy, and incidental durotomy; the most common long-term complications include adjacent segment degeneration, junctional kyphosis, and pseudoarthrosis. Three principal mechanisms are thought to contribute to complications. First, higher number of fusion levels, obesity, and more complex pathologies can increase the invasiveness of the planned procedure, thus increase complications. Second, wound healing and arthrodesis may be impaired due to poor blood flow due to various patient factors such as smoking, diabetes, increased frailty, steroid use, and other medical comorbidities. Finally, increased biomechanical stress on the upper instrumented vertebra (UIV) and lowest instrumented vertebra (LIV) may predispose patient to chronic degeneration and result in adjacent level degeneration and/or junctional problems. Reducing the modifiable risk factors pre-operatively can decrease the overall complication rate. Neurologic deficits may be reduced with adequate intraoperative decompression of neural elements. SSI may be reduced with meticulous wound closure that minimizes dead space, drain placement, and the use of intra-wound antibiotics. Careful design of the fusion construct with consideration in spinal alignment and biomechanics can help to reduce the rate of junctional problems. Spine surgeons should be aware of these complications associated with PCF and the corresponding prevention strategies optimize patient outcomes.

Perioperative acute neurological deficits in instrumented pediatric cervical spine fusions

OBJECTIVE

Pediatric cervical deformity is a complex disorder often associated with neurological deterioration requiring cervical spine fusion. However, limited literature exists on new perioperative neurological deficits in children. This study describes new perioperative neurological deficits in pediatric cervical spine instrumentation and fusion.

METHODS

A single-center review of pediatric cervical spine instrumentation and fusion during 2002-2018 was performed. Demographics, surgical characteristics, and neurological complications were recorded. Perioperative neurological deficits were defined as the deterioration of preexisting neurological function or the appearance of new neurological symptoms.

RESULTS

A total of 184 cases (160 patients, 57% male) with an average age of 12.6 ± 5.30 years (range 0.2-24.9 years) were included. Deformity (n = 39) and instability (n = 36) were the most frequent indications. Syndromes were present in 39% (n = 71), with Down syndrome (n = 20) and neurofibromatosis (n = 12) the most prevalent. Eighty-seven (48%) children presented with preoperative neurological deficits (16 sensory, 16 motor, and 55 combined deficits).A total of 178 (96.7%) cases improved or remained neurologically stable. New neurological deficits occurred in 6 (3.3%) cases: 3 hemiparesis, 1 hemiplegia, 1 quadriplegia, and 1 quadriparesis. Preoperative neurological compromise was seen in 4 (67%) of these new deficits (3 myelopathy, 1 sensory deficit) and 5 had complex syndromes. Three new deficits were anticipated with intraoperative neuromonitoring changes (p = 0.025).Three (50.0%) patients with new neurological deficits recovered within 6 months and the child with quadriparesis was regaining neurological function at the latest follow-up. Hemiplegia persisted in 1 patient, and 1 child died due a complication related to the tracheostomy. No association was found between neurological deficits and indication (p = 0.96), etiology (p = 0.46), preoperative neurological symptoms (p = 0.65), age (p = 0.56), use of halo vest (p = 0.41), estimated blood loss (p = 0.09), levels fused (p = 0.09), approach (p = 0.07), or fusion location (p = 0.07).

CONCLUSIONS

An improvement of the preexisting neurological deficit or stabilization of neurological function was seen in 96.7% of children after cervical spine fusion. New or progressive neurological deficits occurred in 3.3% of the patients and occurred more frequently in children with preoperative neurological symptoms. Patients with syndromic diagnoses are at higher risk to develop a deficit, probably due to the severity of deformity and the degree of cervical instability. Long-term outcomes of new neurological deficits are favorable, and 50% of patients experienced complete neurological recovery within 6 months.