Upper extremity palsy following cervical decompression surgery results from a transient spinal cord lesion

Dysphagia following C1 laminectomy and posterior atlantoaxial fixation for retro-odontoid pseudotumor: a case report

Purpose: Although dysphagia is known potential complication of cervical spine surgery, it rarely occurs after a posterior approach. We describe an unusual case of a retro-odontoid pseudotumor that suffered dysphagia following a C1 laminectomy and posterior atlantoaxial fixation.Materials and methods: A 79-year-old man presented with progressive tetraparesis and bladder and bowel dysfunction due to severe compression to cervical cord at C1 from a retro-odontoid pseudotumor. After C1 laminectomy and atlantoaxial fixation, the symptoms improved, but dysphagia and aspiration developed, associated with pharyngeal and esophageal stases on videofluoroscopy.Results and conclusions: Possible explanations for postoperative dysphagia include limitation of cervical spine motion, and cervical cord reperfusion injury in addition to the baseline anterior osteophyte and aging. This is the first case of dysphagia developing after laminectomy and posterior atlantoaxial fixation not involving the occipital bone.

Cervical spondylotic myelopathy: A two decade experience

Context Cervical myelopathy occurs as a result of compression of the cervical spinal cord. Symptomatology includes, but is not limited to, pain, weakness, paresthesias, or gait/balance difficulties. Objective To present a two-decade experience with the management of cervical myelopathy. Methods Literature was reviewed to provide current guidelines for management as well as accompanying clinical presentations. Results Surgical decompression, if necessary, may be achieved from either an anterior, a posterior, or a combined anterior-posterior (AP) approach. The indications for each approach, as well as the surgical techniques, are described. Conclusion Several etiologies may lead to cord compression and cervical myelopathy. The best vector of approach with regard to anterior versus posterior surgical intervention is still under investigation. Regardless, management via surgical decompression has been demonstrated repeatedly to improve the CSM patients' quality of life.

Can postoperative deltoid weakness after cervical laminoplasty be prevented by using intraoperative neurophysiological monitoring?

Laminoplasty, frequently performed in patients with cervical myelopathy, is safe and provides relatively good results. However, motor palsy of the upper extremities, which occurs after decompression surgery for cervical myelopathy, often reduces muscle strength of the deltoid muscle, mainly in the C5 myotome. The aim of this study was to investigate prospectively whether postoperative deltoid weakness (DW) can be predicted by performing intraoperative neurophysiological monitoring (IONM) during cervical laminoplasty and to clarify whether it is possible to prevent palsy using IONM. We evaluated the 278 consecutive patients (175 males and 103 females) who underwent French-door cervical laminoplasty for cervical myelopathy under IONM between November 2008 and December 2016 at our hospital. IONM was performed using muscle evoked potential after electrical stimulation to the brain [Br(E)-MsEP] from the deltoid muscle. Seven patients (2.5%) developed DW after surgery (2 with acute and 5 with delayed onset). In all patients, deltoid muscle strength recovered to ≥ 4 on manual muscle testing 3-6 months after surgery. Persistent IONM alerts occurred in 2 patients with acute-onset DW. To predict the acute onset of DW, Br(E)-MsEP alerts in the deltoid muscle had both a sensitivity and specificity of 100%. The PPV of persistent Br(E)-MsEP alerts had both a sensitivity and specificity of 100% for acute-onset DW. There was no change in Br(E)-MsEP in patients with delayed-onset palsy. The incidence of deltoid palsy was relatively low. Persistent Br(E)-MsEP alerts of the deltoid muscle had a 100% sensitivity and specificity for predicting a postoperative acute deficit. IONM was unable to predict delayed-onset DW. In only 1 patient were we able to prevent postoperative DW by performing a foraminotomy.

Ossification of the Posterior Longitudinal Ligament in Cervical Spine: Prevalence, Management, and Prognosis

Ossification of the posterior longitudinal ligament (OPLL) in the cervical spine and related neurological complications are not uncommon in East Asian countries. The estimated prevalence of cervical OPLL-related hospitalization is 7.7 per 100,000 person-years in Taiwan, and higher incidence rates have been observed in elderly and male patients. Although cervical OPLL is frequently insidious, it can eventually cause myelopathy and predispose patients to spinal cord injury (SCI). There are multiple options for managing cervical OPLL, ranging from observation to many kinds of surgical procedures, including posterior laminoplasty, laminectomy with or without fusion, anterior corpectomy with or without instrumentation, and circumferential decompression and fusion. None of these surgical approaches is free of complications. However, to date, there is still a lack of consensus regarding the choice of the surgical approach and the timing of surgical intervention. Cervical SCI and related neurological disabilities are more likely to occur in OPLL patients, who should therefore be cautioned regarding the possibility of a subsequent SCI if treated without surgery. This article aimed to review the prevalence, management strategies, and prognosis of cervical OPLL.

Analysis of C5 palsy in cervical myelopathy with massive anterior compression following laminoplasty

BACKGROUND

Little data is available about comparison of the incidence and clinical characteristics of the C5 palsy between patients of cervical myelopathy with occupying ratio greater than 50% and those with occupying ratio less than 50% following laminoplasty.

METHODS

One-hundred eighteen patients with cervical myelopathy who underwent open door laminoplasty were reviewed in this study. The patients were divided into two groups: group A comprising 55 patients with an anterior occupying ratio greater than 50% and group B comprising 63 patients with an anterior occupying less than 50%. Clinical and radiological outcomes were assessed between two groups.

RESULTS

No statistically difference was found in preoperative Japanese Orthopedic Association (JOA) score of both groups (10.7 ± 1.7 in group A vs 10.9 ± 1.1 in group B, P > 0.05). Improvements in postoperative JOA score were achieved, and there was a statistical difference (14.0 ± 1.4 in group A vs 14.8 ± 0.9 in group B, P < 0.05). Group A had a lower rate of recovery than group B (P < 0.05). Totally, 12 of 118 (10.2%) patients developed the C5 palsy postoperatively. C5 palsy occurred in 3 of 63 patients in the group B compared with 9 of 55 in the group A. Statistically significant difference was found in the incidence of C5 palsy between the two groups (P < 0.05). Furthermore, patients in group A required significantly longer recovery periods than group B. Both preoperative and postoperative MRI presented more levels of T2 high-signal lesion in group A than group B. The degree of posterior shift of the cord after posterior decompression in group A was less than group B (P < 0.05).

CONCLUSIONS

Patients with a high degree of anterior compression have higher risk of C5 palsy than those with a relative low degree of anterior compression.

Cement plug technique for the management of disc-associated cervical spondylopathy in 52 Dobermann Pinscher dogs

Objectives: To report the radiographic and clinical outcome of an intervertebral bone cement plug technique for the management of disc-associated cervical spondylopathy in Dobermann Pinscher dogs.

Methods: Retrospective study of 52 Dobermann Pinscher dogs.

Results: A variable degree of cement plug subsidence with loss of vertebral distraction was evident in all dogs (n = 40) that were radiographed >6 weeks postoperatively. In no case was there definitive evidence of vertebral body fusion. Eight dogs had a sudden deterioration in neurological status, cervical hyperaesthesia, or both between three days and 12 weeks following surgery that was considered to be implant-associated; six of these dogs were euthanatized. Following surgery, 43/52 dogs were considered to be neurologically normal or to have improved, however, nine of 43 subsequently deteriorated due to adjacent segment disease. At the long-term follow-up, 34 dogs were considered to be neurologically normal or to have improved. Twenty-nine dogs were dead by the end of the study period.

Clinical significance: Intervertebral bone cement plug surgery results in an initial improvement in clinical signs in the majority of Dobermann Pinschers with disc-associated cervical spondylopathy. However, it fails to maintain vertebral distraction or achieve vertebral body fusion, and is associated with acute implant complications, additional cervical disc protrusions or mortality in a significant proportion of cases.

Online Supplementary Material: Please note that online supplementary material for this paper is available at: http://dx.doi.org/10.3415/VCOT-15-09-0160.

Risk factors of cervical surgery related complications in patients older than 80 years

Introduction

With an aging population, the proportion of patients aged ≥80 years requiring cervical surgery is increasing. Surgeons are concerned with the high incidence of complications in this population, because “age” itself has been reported as a strong risk factor for complications. However, it is still unknown which factors represent higher risk among these elderly patients. Therefore, this study was conducted to identify the risk factors related to surgical complications specific to elderly patients by analyzing the registry data of patients aged ≥80 years who underwent cervical surgery.

Methods

We retrospectively studied multicenter collected registry data using multivariate analysis. Sixty-six patients aged ≥80 years who underwent cervical surgery and were followed up for more than one year were included in this study. Preoperative patient demographic data, including comorbidities and postoperative complications, were collected from multicenter registry data. Complications were considered as major if they required invasive intervention, caused prolonged morbidity, or resulted in prolongation of hospital stay. Logistic regression analysis was performed to analyze the risk factors for complications. A p-value of <0.05 was considered as statistically significant.

Results

The total number of patients with complications was 21 (31.8%), with seven major (10.6%) and 14 minor (21.2%) complications. Multivariate logistic regression analysis, after adjusting for age, revealed two significant risk factors: preoperative cerebrovascular disorders (OR, 6.337; p=0.043) for overall complications and cancer history (OR, 8.168; p=0.021) for major complications. Age, presence of diabetes mellitus, and diagnosis were not significant predictive factors for complications in this study.

Conclusions

Preoperative cerebrovascular disorders and cancer history were risk factors for complications after cervical surgery in patients over 80 years old. Surgeons should pay attention to these specific risk factors before performing cervical surgery in elderly patients.

Impact of the surgical strategy on the incidence of C5 nerve root palsy in decompressive cervical surgery

Objective

Our aim was to identify the impact of different surgical strategies on the incidence of C5 palsy.

Background

Degenerative cervical spinal stenosis is a steadily increasing morbidity in the ageing population. Postoperative C5 nerve root palsy is a common complication with severe impact on the patients´ quality of life.

Methods

We identified 1708 consecutive patients who underwent cervical decompression surgery due to degenerative changes. The incidence of C5 palsy and surgical parameters including type and level of surgery were recorded to identify predictors for C5 nerve palsy.

Results

The overall C5 palsy rate was 4.8%, with 18.3% of cases being bilateral. For ACDF alone the palsy rate was low (1.13%), compared to 14.0% of C5 palsy rate after corpectomy. The risk increased with extension of the procedures. Hybrid constructs with corpectomy plus ACDF at C3-6 showed significantly lower rates of C5 palsy (10.7%) than corpectomy of two vertebrae (p = 0.005). Multiple regression analysis identified corpectomy of C4 or C5 as a significant predictor. We observed a lower overall incidence for ventral (4.3%) compared to dorsal (10.9%) approaches (p<0.001). When imaging detected a postoperative shift of the spinal cord at index segment C4/5, palsy rate increased significantly (33.3% vs. 12.5%, p = 0.034).

Conclusions

Extended surgical strategies, such as dorsal laminectomies, multilevel corpectomies and procedures with extensive spinal cord shift were shown to display a high risk of C5 palsy. The use of extended procedures should therefore be employed cautiously. Switching to combined surgical methods like ACDF plus corpectomy can reduce the rate of C5 palsy.

Consequences of intraoperative spinal cord manipulation in dogs with thoracolumbar intervertebral disc extrusion

ABSTRACT The objective of the present study was to evaluate if extradural contact during hemilaminectomy would cause neurological deterioration in the early and/or late postoperative period in dogs with intervertebral disc extrusion. Nineteen dogs with thoracolumbar intervertebral disc extrusion underwent hemilaminectomy for spinal cord decompression and removal of extruded disc material. Meningeal contacts during surgery were quantified. Paraplegia (with nociception) and paraparesis were observed in 11/19 and 8/19 of dogs, respectively, before surgery. At the end of our study, only two (2/19) had paraplegia and one (1/19), paraparesis. There were more extradural contacts when extruded intervertebral disc material was at a ventrolateral position. Extradural contacts during surgery had no influence on neurological progression nor on time to recovery of motor function. Immediately (24 and 48 hours) after surgery, 13/19 dogs had the same neurological stage before surgery. At 7 and 90 days, 13/19 and 17/19 dogs, respectively, showed neurological improvement, compared with their preoperative stage. There was no influence of the number of extradural contacts on neurological recovery. These findings indicate that a careful inspection of the vertebral canal for removal of as much extruded disc material as possible does not cause neurologic deterioration.

Preoperative Risk Factors of C5 Nerve Root Palsy After Laminectomy and Fusion in Patients With Cervical Myelopathy: Analysis of 70 Consecutive Patients

STUDY DESIGN

A retrospective study.

OBJECTIVE

To identify preoperative risk factors causing cervical fifth nerve root palsy (C5 palsy) after laminectomy and fusion (LF).

SUMMARY OF BACKGROUND DATA

It is well known that postoperative C5 palsy is not rare after cervical surgery. Although there remains controversy, C5 palsy is considered to be more common in patients who had LF than in those who had laminoplasty. However, the reason for the higher incidence of C5 palsy in patients with LF has been poorly understood.

METHODS

A total of 70 consecutive patients (mean age: 60.3 y) who had LF due to cervical myelopathy were reviewed. Patients were divided on the basis of the presence (group P) or absence (group N) of C5 palsy. Among various risk factors for C5 palsy from previous reports, 6 risk factors were selected as follows: (1) preoperative low Japanese Orthopedic Association score, (2) postoperatively increased lordosis, (3) low Pavlov ratio, (4) high signal intensity in the cord at C3-C5, (5) anterior protruding mass lesion compressing the spinal cord, and (6) presence of C4-C5 foraminal stenosis. With these factors, the 2 groups were compared by statistical analysis.

RESULTS

C5 palsy occurred in 10 patients (14.3%). The mean onset time was 3.5 days (range, 1-8 d) and the mean recovery time was 3.4 months (range, 1-7 mo). There were no significant differences in the preoperative Japanese Orthopedic Association score, cervical lordosis, Pavlov ratio, high signal intensity, and anterior protruding mass between the 2 groups (P>0.05). However, C4-C5 foraminal stenosis was found in 80.0% (8/10) in group P and 21.7% (13/60) in group N. There were significant differences between the 2 groups in C4-C5 foraminal stenosis (P=0.004).

CONCLUSIONS

In this study, a high occurrence rate and risk factor for C5 palsy were verified after LF. Among the various factors, C4-C5 foraminal stenosis was the only risk factor for C5 palsy. Preoperative warning for C5 palsy after LF seems to be imperatively necessary, especially in patients with C4-C5 foraminal stenosis.

Comparing the Effectiveness of Sagittal Balance, Foraminal Stenosis, and Preoperative Cord Rotation in Predicting Postoperative C5 Palsy

STUDY DESIGN

Retrospective cohort review.

OBJECTIVE

To determine whether preoperative cord rotation is independently correlated with C5 palsy when analyzed alongside measures of sagittal balance and foraminal stenosis.

SUMMARY OF BACKGROUND DATA

Postoperative C5 palsy is a well-documented complication of cervical procedures with a prevalence of 4%-8%. Recent studies have shown a correlation with preoperative spinal cord rotation. There have been few studies, however, that have examined the role of sagittal balance and foraminal stenosis in the development of C5 palsy.

METHODS

A total of 77 patients who underwent cervical decompression-10 of whom developed C5 palsy-were reviewed. Sagittal balance was assessed using curvature angle and curvature index on radiographs and magnetic resonance image (MRI). Cord rotation was assessed on axial MRI. C4-C5 foraminal stenosis was assessed on sagittal MRI using area measurements and a grading scale. Demographics and information on surgical approach were gathered from chart review. Correlation with C5 palsy was performed by point-biserial, χ, and regression analyses.

RESULTS

Point-biserial analysis indicated that only cord rotation showed significance (P<0.01). There was no statistical significance shown with surgical approach, sex, or age. In addition, changes in sagittal balance did not correlate with presence of C5 palsy. Logistic regression model yielded cord rotation as the only significant independent predictor of C5 palsy. For every degree of axial cord rotation, the likelihood ratio for suffering a C5 palsy was 3.93 (95% confidence interval, 2.01-8.66; P<0.05).

CONCLUSIONS

This supports the independent capability of preoperative cord rotation to predict postoperative C5 palsy. Lack of correlation with measures of neuroforaminal stenosis potentially points to mechanisms other than direct compression as the etiology. In addition, the lack of correlation with postoperative changes in sagittal balance hints that measures of curvature angle and curvature index may not be appropriate to accurately predict this complication.

LEVEL OF EVIDENCE

Level 3.

Incidence of C5 nerve root palsy after cervical surgery: A meta-analysis for last decade

PURPOSE

We aim to perform a meta-analysis on incidence of C5 nerve root palsy (C5 palsy) for patients after cervical surgery.

METHODS

An extensive search of the literature was performed in PubMed/MEDLINE, Embase, the Cochrane library, CNKI, and WANFANG databases on incidence of C5 palsy from January 2007 to January 2017. Prevalence of C5 palsy related to different surgery methods was calculated and data analysis was conducted with STATA 12.0.

RESULTS

A total of 61 studies containing 721 patients with C5 palsy in total 11,481 patients (6.3%) were included in our study. The incidences after anterior cervical discectomy and fusion (ACDF), anterior cervical corpectomy and fusion (ACCF), anterior corpectomy combined with discectomy (ACCDF), laminoplasty (LP) and laminectomy and fusion (LF) were 5.5%, 7.5%, 6%, 4.4%, and 12.2%, respectively. Compared with anterior approaches (5%), female patients (4%) and patients with cervical spondylotic myelopathy (CSM) (4.8%), posterior approaches (6.2%), male patients (5.7%) and patients with ossification of posterior longitudinal ligament (OPLL) (8.1%) have a higher prevalence. In ACDF and LP, patients with OPLL (5.5%, 8.1%, respectively) have a higher incidence than those in patients with CSM (4.7%, 3.1%, respectively); however, in LF, patients with CSM and OPLL have similar incidence of C5 palsy (13% vs 13.1%). In most cases, C5 palsy was unilateral (74.5%).

CONCLUSIONS

Based on our meta-analysis, posterior approaches, male patients and patients with OPLL have a higher incidence of C5 palsy. In ACDF and LP, patients with OPLL have a higher incidence of C5 palsy, but in LF, patients with CSM and OPLL have similar result.

Bilateral C5 Motor Palsy after Anterior Cervical Decompression and Fusion: A Case Report and Review of the Literature

BACKGROUND

Bilateral C5 motor palsy is a rare but potentially debilitating complication after cervical spine decompression with very few reports in the published literature.

PURPOSE

To present a case of bilateral C5 motor palsy after anterior cervical decompression and fusion and discuss the incidence and risk factors of this complication.

STUDY DESIGN/SETTING

We report a case of a 57-year-old male who underwent a three level C3-C6 anterior cervical discectomy and fusion with instrumentation who developed a postoperative bilateral C5 motor palsy.

METHODS

A review of the literature was performed regarding reports on and incidence of post-operative bilateral C5 palsy following either anterior or posterior cervical spine decompression.

RESULTS

Bilateral C5 motor palsy is a rare complication of cervical spine decompression with an overall incidence of 0.38%. Although a group of risk factors have been suggested no single cause has been identified.

CONCLUSIONS

Bilateral C5 motor palsy is a rare but debilitating complication of cervical decompression.

Factors associated with postoperative C5 palsy after expansive open-door laminoplasty: retrospective cohort study using multivariable analysis

PURPOSE

The aim of the present study was to investigate the factors associated with C5 palsy by focusing on radiological parameters using multivariable analysis.

METHODS

The authors retrospectively assessed 190 patients with cervical spondylotic myelopathy treated by open-door laminoplasty. Four radiographic parameters-the number of expanded lamina, C3-C7 angle, lamina open angle and space anterior to the spinal cord-were evaluated to clarify the factors associated with C5 palsy.

RESULTS

Of the 190 patients, 11 developed C5 palsy, giving an overall incidence of 5.8%. Although the number of expanded lamina, lamina open angle and space anterior to the spinal cord were significantly larger in C5 palsy group than those in non-palsy group, a multiple logistic regression analysis revealed that only the space anterior to the spinal cord (odds ratio 2.60) was a significant independent factor associated with C5 palsy. A multiple linear regression analysis indicated that the lamina open angle was associated with the space anterior to the spinal cord and the analysis identified the following equation: space anterior to the spinal cord (mm) = 1.54 + 0.09 × lamina open angle (degree). A cut-off value of 53.5° for the lamina open angle predicted the development of C5 palsy with a sensitivity of 72.7% and a specificity of 83.2%.

CONCLUSIONS

The larger postoperative space anterior to the spinal cord, which was associated with the lamina open angle, was positively correlated with the higher incidence of C5 palsy.

Intraoperative motor evoked potential monitoring to patients with preoperative spinal deficits: judging its feasibility and analyzing the significance of rapid signal loss

BACKGROUND CONTEXT

Transcranial motor evoked potential (MEP) monitoring has been widely adopted in spine surgery, but so far the useful monitoring data for patients with preoperative spinal deficits (PPSDs) are limited. Originally we thought that they seemed technically more difficult and less reliable in performing the MEP monitoring to PPSDs.

PURPOSE

Our objective was to study (1) the feasibility of MEP monitoring in PPSDs and the (2) the significance of rapid MEP loss.

STUDY DESIGN/SETTING

A retrospective case notes study from a prospective patient register was used as the study design.

PATIENT SAMPLE

A total of 332 PPSDs who underwent posterior spine surgery with a reliable MEP monitoring were collected between September 2010 and December 2014.

OUTCOME MEASURES

Relevant MEP loss was identified as rapid amplitude reduction (more than 80% MEP) associated with high-risk surgical maneuvers or high-risk diagnoses.

METHOD

The muscles with higher strength were used to record the optimal MEP signal. MEP monitoring of these patients was considered to be feasible if reproducible signals had been obtained; moreover, sensitivity, specificity, positive predictive value (PPV), and negative predictive value were computed. The significance of the patients with rapid MEP loss was analyzed.

RESULTS

From a total of 332 PPSDs, 27 cases showed significant MEP loss (23 true positive, 4 false positive), and 21 showed new spinal deficits. Invalid MEP baselines were found in 11 paralysis and 6 severely incomplete paraplegia patients, and success rate of reliable MEP was 95.1% in PPSDs. The congenital kyphoscoliosis, tuberculous kyphoscoliosis, and thoracic spinal stenosis are considered high-risk diagnoses to result in MEP loss. The sensitivity of intraoperative MEP monitoring was 100%, the specificity 98.7%, the positive predictive value 85.2%, and the negative predictive value 100%.

CONCLUSIONS

Intraoperative MEP monitoring is feasible for most of the PPSDs. The rapid MEP loss during high-risk diagnoses and complicated surgical procedures may indicate new spinal deficits.

Diagnostic Accuracy of Somatosensory Evoked Potentials in Evaluating New Neurological Deficits After Posterior Cervical Fusions

STUDY DESIGN

This study examined the diagnostic accuracy of significant changes of somatosensory evoked potentials (SSEPs) to evaluate and predict postoperative neurological deficits after posterior cervical fusions (PCF). Eight hundred forty six eligible patients underwent PCF at the University of Pittsburgh Medical Center (UPMC), from 2010 to 2012.

OBJECTIVE

To assess the specificity and sensitivity of intraoperative monitoring in predicting postoperative neurological deficits during PCF.

SUMMARY OF BACKGROUND DATA

We calculated the predictive value, including sensitivity and specificity, of changes in SSEPs to identify neurological deficits postoperatively. We used a receiver operating characteristic (ROC) curve with SSEP categories as cutoff values to further evaluate the diagnostic accuracy of change in SSEPs and postoperative neurological deficit.

METHODS

All patients had preposition baselines and continuous SSEP monitoring throughout the surgery. Statistical analysis was completed using SPSS version 22 (IBM Corp., Armonk, NY).

RESULTS

Age and sex did not influence outcomes. Obesity affected patient outcome. The SSEP categories of significant changes and loss of responses resulted in a sensitivity/specificity of 0.30/0.96 and 0.16/0.98, respectively. The receiver operating characteristic curve has an area under the curve for significant change in/loss of SSEPs of 0.62/0.65 with a 95% confidence interval of 0.525 to 0.714/0.509 to 0.797.

CONCLUSION

Significant SSEP changes during PCF are a very specific but poorly sensitive indicator of postoperative neurological deficits. The odds ratio for significant changes in SSEPs and loss of waveforms was 9.80 and 11.82, respectively, with a 95% confidence interval of 4.695 to 20.46 and 4.45 to 31.41, respectively.

LEVEL OF EVIDENCE

1.

Brachial Plexopathy After Cervical Spine Surgery

STUDY DESIGN

Retrospective, multicenter case-series study and literature review.

OBJECTIVES

To determine the prevalence of brachial plexopathy after cervical spine surgery and to review the literature to better understand the etiology and risk factors of brachial plexopathy after cervical spine surgery.

METHODS

A retrospective case-series study of 12 903 patients at 21 different sites was performed to analyze the prevalence of several different complications, including brachial plexopathy. A literature review of the US National Library of Medicine and the National Institutes of Health (PubMed) database was conducted to identify articles pertaining to brachial plexopathy following cervical spine surgery.

RESULTS

In our total population of 12 903 patients, only 1 suffered from postoperative brachial plexopathy. The overall prevalence rate was thus 0.01%, but the prevalence rate at the site where this complication occurred was 0.07%. Previously reported risk factors for postoperative brachial plexopathy include age, anterior surgical procedures, and a diagnosis of ossification of the posterior longitudinal ligament. The condition can also be due to patient positioning during surgery, which can generally be detected via the use of intraoperative neuromonitoring.

CONCLUSIONS

Brachial plexopathy following cervical spine surgery is rare and merits further study.

C5 Palsy After Cervical Spine Surgery: A Multicenter Retrospective Review of 59 Cases

STUDY DESIGN

A multicenter, retrospective review of C5 palsy after cervical spine surgery.

OBJECTIVE

Postoperative C5 palsy is a known complication of cervical decompressive spinal surgery. The goal of this study was to review the incidence, patient characteristics, and outcome of C5 palsy in patients undergoing cervical spine surgery.

METHODS

We conducted a multicenter, retrospective review of 13 946 patients across 21 centers who received cervical spine surgery (levels C2 to C7) between January 1, 2005, and December 31, 2011, inclusive. P values were calculated using 2-sample t test for continuous variables and χ² tests or Fisher exact tests for categorical variables.

RESULTS

Of the 13 946 cases reviewed, 59 patients experienced a postoperative C5 palsy. The incidence rate across the 21 sites ranged from 0% to 2.5%. At most recent follow-up, 32 patients reported complete resolution of symptoms (54.2%), 15 had symptoms resolve with residual effects (25.4%), 10 patients did not recover (17.0%), and 2 were lost to follow-up (3.4%).

CONCLUSION

C5 palsy occurred in all surgical approaches and across a variety of diagnoses. The majority of patients had full recovery or recovery with residual effects. This study represents the largest series of North American patients reviewed to date.

Simvastatin protects ischemic spinal cord injury from cell death and cytotoxicity through decreasing oxidative stress: in vitro primary cultured rat spinal cord model under oxygen and glucose deprivation-reoxygenation conditions

Background

Ischemia and the following reperfusion damage are critical mechanisms of spinal cord injury. Statins have been reported to decrease ischemia–reperfusion injury in many organs including the spinal cord. Anti-oxidative effect is one of the main protective mechanisms of statin against neuronal death and cytotoxicity. We hypothesized that statins’ anti-oxidative property would yield neuroprotective effects on spinal cord ischemia–reperfusion injury

Methods

Primary cultured spinal cord motor neurons were isolated from Sprague–Dawley rat fetuses. Ischemia–reperfusion injury model was induced by 60 min of oxygen and glucose deprivation (OGD) and 24 h of reoxygenation. Healthy and OGD cells were treated with simvastatin at concentrations of 0.1, 1, and 10 μM for 24 h. Cell viability was assessed using water-soluble tetrazolium salt (WST)-8, cytotoxicity with LDH, and production of free radicals with DCFDA (2′,7′-dichlorofluorescein diacetate).

Results

OGD reduced neuronal viability compared to normoxic control by 35.3%; however, 0.1–10 μM of simvastatin treatment following OGD improved cell survival. OGD increased LDH release up to 214%; however, simvastatin treatment attenuated its cytotoxicity at concentrations of 0.1–10 μM (p < 0.001 and p = 0.001). Simvastatin also reduced deteriorated morphological changes of motor neurons following OGD. Oxidative stress was reduced by simvastatin (0.1–10 μM) compared to untreated cells exposed to OGD (p < 0.001).

Conclusions

Simvastatin effectively reduced spinal cord neuronal death and cytotoxicity against ischemia–reperfusion injury, probably via modification of oxidative stress.

A Delayed Postoperative C5 Palsy due to Spinal Cord Lesion: A Typical Clinical Presentation but Unusual Imaging Findings

Postoperative C5 palsy (C5 palsy) is a troublesome complication after cervical spine surgery and its etiology is still unclear. We experienced a case of C5 palsy after anterior decompression with fusion for cervical ossification of posterior longitudinal ligament with the typical clinical presentation of left deltoid and bicep weakness and left-arm pain without deterioration of myelopathy symptoms, albeit with the unusual imaging findings not shown preoperatively of a swelling in the spinal cord, and intramedullary high intensity change on T2-weighed MRI. The additional posterior surgery was carried out to decompress the swollen spinal cord. The abnormal findings disappear on MRI taken three weeks following the second surgery and the weakness improved fully within three months after the second surgery. This case report highlights the possibility of spinal cord lesion due to circulatory impairment as a cause of C5 palsy.

C5 nerve root palsy after posterior cervical spine surgery

BACKGROUND

C5 palsy is a serious complication after cervical decompression surgery in which the patient shows a deterioration in power of the deltoid or biceps brachii by at least one grade in the manual muscle test without aggravation of lower extremity function. Although there are several hypotheses regarding the etiology of C5 palsy, the pathogenesis and preventive measures remain unidentified and many other controversies remain.

OBJECTIVE

To systematically review the clinical features, risk factors, mechanism, and preventive measures of C5 palsy after posterior cervical decompression surgery.

MATERIALS AND METHODS

PubMed was searched to identify eligible studies that contained more than 10 cases and focused on C5 palsy. Microsoft Excel was used to analyze the data. Statistical comparisons were made when appropriate.

RESULTS

Out of 718 papers involving C5 palsy, 28 met the inclusion criteria. The average incidence rate was 7.8% (range, 1.4-23.0%). Risk factors for C5 palsy included age, male gender, ossification of the posterior longitudinal ligament, and stenosis of the C4-C5 intervertebral foramen. C5 palsy occurred from immediately to 2 months after surgery, and recovery time ranged from 48 h to 41 months. Hypotheses for the mechanism of C5 palsy included root involvement and spinal cord impairment. Foraminotomy and intraoperative neuromonitoring were the two main methods used to prevent C5 palsy.

CONCLUSION

C5 palsy is a serious complication occurring at the early stage after cervical decompression surgery. Foraminotomy and intraoperative neuromonitoring were the two main methods to prevent C5 palsy. The incidence of C5 palsy is low, but it can place a serious burden on the patients' quality of life and finances. The risk factors and mechanism of C5 palsy are still controversial. However, under conservative therapy, the prognosis is usually good. Higher quality studies are necessary for drawing more reliable and convincing conclusions about this disease.

Differences in the time of onset of postoperative upper limb palsy among surgical procedures: a meta-analysis

BACKGROUND CONTEXT

The time of onset of postoperative upper limb palsy (ULP), also referred to as C5 palsy, varies among patients. Although some studies addressed the relationship between the time of onset of ULP and the potential etiologies, no meta-analysis has been conducted regarding the association between the time of onset of ULP and other factors such as surgical procedure type and treated diseases.

PURPOSE

This study aimed to elucidate differences in the time of onset of ULP among spinal surgical procedures and treated diseases to understand its etiology.

STUDY DESIGN

This is a meta-analysis.

OUTCOME MEASURES

The time of onset of ULP after cervical decompression surgery.

METHODS

We conducted a meta-analysis via searches of the PubMed, EMBASE, and Cochrane Library databases. Upper limb palsy within 2 days postoperatively or at 3 days or more postoperatively was defined as early- and late-onset, respectively. We calculated the pooled prevalence of early- and late-onset ULP with regard to surgical procedures and diseases using a random effects model. The proportion of early-onset ULP relative to all ULP was also determined. Surgical procedures were categorized into four procedures: (1) anterior cervical discectomy and fusion (ACDF); (2) anterior cervical corpectomy and fusion (ACCF); (3) laminoplasty or laminectomy (LPN); and (4) posterior spinal fusion with decompression (PSF). Treated diseases were classified as ossification of the posterior longitudinal ligament (OPLL) and non-OPLL.

RESULTS

The pooled prevalence of early-onset ULP was significantly stratified across three groups of surgical procedures (PSF [9.0%]>ACCF [3.7%] and LPN [2.5%]>ACDF [0.6%]). In the pooled analysis of late-onset ULP prevalence, three procedures (PSF [4.3%], ACCF [2.8%], and LPN [2.9%]) were similar, but ACDF (1.0%) was associated with a significantly lower prevalence than LPN. The prevalence of both early- and late-onset ULP was significantly higher with OPLL than without OPLL. However, the proportion of early-onset ULP relative to all ULP was similar between non-OPLL and OPLL (50.8% vs. 49.5%).

CONCLUSIONS

The high prevalence of early-onset ULP in PSF is attributable to a lag correction effect, which is triggered by posterior correction and fusion through comparison with LPN. The combination of our meta-analysis results and previous knowledge facilitates our understanding of the etiology of ULP.

Postoperative Delayed Cervical Palsies: Understanding the Etiology

STUDY DESIGN

Retrospective study.

OBJECTIVE

This study reviews 1,768 consecutive cervical decompressions with or without instrumented fusion to identify patient-specific and procedural risk factors significantly correlated with the development of delayed cervical palsy (DCP).

METHODS

Baseline demographic and procedural information was collected from the electronic medical record. Particular attention was devoted to reviewing each chart for recognized risk factors of postsurgical inflammatory neuropathy: autoimmune disease, blood transfusions, diabetes, and smoking.

RESULTS

Of 1,669 patients, 56 (3.4%) developed a DCP. Although 71% of the palsies involved C5, 55% of palsies were multimyotomal and 18% were bilateral. Significant risk factors on univariate analysis included age (p = 0.0061, odds ratio [OR] = 1.07, 95% confidence interval [CI] 1.008 to 1.050), posterior instrumented fusion (p < 0.0001, OR = 3.30, 95% CI 1.920 to 5.653), prone versus semisitting/sitting position (p = 0.0036, OR = 3.58, 95% CI 1.451 to 11.881), number of operative levels (p < 0.0001, OR = 1.42, 95% CI 1.247 to 1.605), intraoperative transfusions (p = 0.0231, OR = 2.57, 95% CI 1.152 to 5.132), and nonspecific autoimmune disease (p = 0.0107, OR = 3.83, 95% CI 1.418 to 8.730). On multivariate analysis, number of operative levels (p = 0.0053, OR = 1.27, 95% CI 1.075 to 1.496) and nonspecific autoimmune disease (p = 0.0416, OR 2.95, 95% CI 1.047 to 7.092) remained significant.

CONCLUSIONS

Although this study partially supports a mechanical etiology in the pathogenesis of a DCP, we also describe a notable correlation with autoimmune risk factors. Bilateral and multimyotomal involvement provides additional support that some DCPs may result from an inflammatory response and thus an underlying multifactorial etiology for this complication.

Can intraoperative neurophysiologic monitoring during cervical spine decompression predict post-operative segmental C5 palsy?

BACKGROUND

C5 nerve root palsy is a known complication after cervical laminectomy or laminoplasty, characterized by weakness of the deltoid and bicep brachii muscles. The efficacy of intraoperative monitoring of these muscles is currently unclear. In the current prospective study, intraoperative monitoring through somatosensory (SSEPs), motor (TcMEPs) evoked potentials and real-time electromyography activity (EMG) were analyzed for their ability to detect or prevent deltoid muscle weakness after surgery.

METHODS

One hundred consecutive patients undergoing laminectomy/laminoplasty with or without fusion were enrolled. Intraoperative SSEPs, TcMEPs and EMGs from each patient were studied and analyzed.

RESULTS

Intraoperative EMG activity of the C5 nerve root was detected in 34 cases, 10 of which demonstrated a sustained and repetitive EMG activity lasting 5 or more minutes. Paresis of the unilateral deltoid muscle developed in 5 patients, all from the group with sustained C5 EMG activity. None of the patients with weakness of deltoid muscle after surgery demonstrated any abnormal change in TcMEP or SSEP.

CONCLUSIONS

Real-time EMG recordings were sensitive to C5 nerve root irritation, whilst SSEPs and TcMEPs were not. Sustained EMG activity of the C5 nerve root during surgery is a possible warning sign of irritation or injury to the nerve.

Complications following central corpectomy in 468 consecutive patients with degenerative cervical spine disease

OBJECTIVE

This study was performed to describe the incidence and predictors of perioperative complications following central corpectomy (CC) in 468 consecutive patients with cervical spondylotic myelopathy (CSM) or ossification of the posterior longitudinal ligament (OPLL).

METHODS

The authors performed a retrospective review of a cohort of patients who had undergone surgery for CSM (n = 338) or OPLL (n = 130) performed by a single surgeon over a 15-year period. All patients underwent uninstrumented CC with autologous iliac crest or fibular strut grafting. Preoperative clinical and imaging details were collected, and the type and incidence of complications were studied. Univariate and multivariate analyses were performed to establish risk factors for the development of perioperative complications.

RESULTS

Overall, 12.4% of patients suffered at least 1 complication following CC. The incidence of major complications was as follows: C-5 radiculopathy, 1.3%; recurrent laryngeal nerve injury, 0.4%; dysphagia, 0.8%; surgical-site infection, 3.4%; and dural tear, 4.3%. There was 1 postoperative death (0.2%). On multivariate analysis, patients in whom the corpectomy involved the C-4 vertebral body (alone or as part of multilevel CC) were significantly more likely to suffer complications (p = 0.004). OPLL and skip corpectomy were risk factors for dural tear (p = 0.015 and p = 0.001, respectively). No factors were found to be significantly associated with postoperative C-5 palsy, dysphagia, or acute graft extrusion on univariate or multivariate analysis. Patients who underwent multilevel CC were predisposed to surgical-site infections, with a slight trend toward statistical significance (p = 0.094). The occurrence of a complication after surgery significantly increased the mean duration of postoperative hospital stay from 5.0 ± 2.3 days to 8.9 ± 6 days (p < 0.001).

CONCLUSIONS

Complications following CC for CSM or OPLL are infrequent, but they significantly prolong hospital stay. The most frequent complication following CC is dural tear, for which a diagnosis of OPLL and a skip corpectomy are significant risk factors.

The Efficacy of Intraoperative Neurophysiological Monitoring Using Transcranial Electrically Stimulated Muscle-evoked Potentials (TcE-MsEPs) for Predicting Postoperative Segmental Upper Extremity Motor Paresis After Cervical Laminoplasty

STUDY DESIGN

Prospective study.

OBJECTIVE

To investigate the efficacy of transcranial electrically stimulated muscle-evoked potentials (TcE-MsEPs) for predicting postoperative segmental upper extremity palsy following cervical laminoplasty.

SUMMARY OF BACKGROUND DATA

Postoperative segmental upper extremity palsy, especially in the deltoid and biceps (so-called C5 palsy), is the most common complication following cervical laminoplasty. Some papers have reported that postoperative C5 palsy cannot be predicted by TcE-MsEPs, although others have reported that it can be predicted.

METHODS

This study included 160 consecutive cases that underwent open-door laminoplasty, and TcE-MsEP monitoring was performed in the biceps brachii, triceps brachii, abductor digiti minimi, tibialis anterior, and abductor hallucis. A >50% decrease in the wave amplitude was defined as an alarm point. According to the monitoring alarm, interventions were performed, which include steroid administration, foraminotomies, etc.

RESULTS

Postoperative deltoid and biceps palsy occurred in 5 cases. Among the 155 cases without segmental upper extremity palsy, there were no monitoring alarms. Among the 5 deltoid and biceps palsy cases, 3 had significant wave amplitude decreases in the biceps during surgery, and palsy occurred when the patients awoke from anesthesia (acute type). In the other 2 cases in which the palsy occurred 2 days after the operation (delayed type), there were no significant wave decreases. In all of the cases, the palsy was completely resolved within 6 months.

DISCUSSION

The majority of C5 palsies have been reported to occur several days after surgery, but some of them have been reported to occur immediately after surgery. Our results demonstrated that TcE-MsEPs can predict the acute type, whereas the delayed type cannot be predicted.

CONCLUSIONS

A >50% wave amplitude decrease in the biceps is useful to predict acute-type segmental upper extremity palsy. Further examination about the interventions for monitoring alarm will be essential for preventing palsy.

Outcomes and Related Factors of C5 Palsy Following Cervical Laminectomy With Instrumented Fusion Compared With Laminoplasty

STUDY DESIGN

A retrospective study.

OBJECTIVE

The aim of this study was to analyze the clinical outcomes and related factors of C5 palsy (C5P) following posterior cervical laminectomy with fusion (LF) compared with laminoplasty (LP).

SUMMARY OF BACKGROUND DATA

C5P is more common after LF than after LP. There have not been any studies on C5P-LF compared with C5P-LP.

METHODS

We retrospectively analyzed consecutive cases that underwent cervical LF for nontraumatic cervical myelopathy or myeloradiculopathy (CMR). To analyze the related factors, C5P-LF and non-C5P-LF groups were compared. To assess the clinical parameters, preoperative diagnosis, clinical symptoms, surgical procedures, and outcome instruments were analyzed. Radiographically, we analyzed preoperative maximal spinal cord compression ratio, presence of C4-5 foraminal stenosis (FS), and correction angles on the sagittal plane. To compare with C5P-LP, we analyzed the incidence, time of onset, grade of muscle weakness, other accompanying cervical nerve root palsies, recovery time, and degree of final recovery in the C5P-LF and the C5P-LP groups of 100 consecutive LPs.

RESULTS

A total of 90 LF patients were enrolled (M:F = 54:36, mean age 61.1 yr, mean follow-up 35 months). C5P occurred in 26 patients (28.9%), and 14 cases (53.8%) demonstrated other cervical nerve root palsies. Clinically significant differences were observed between the C5P-LF and non-C5P-LF groups with regard to preoperative clinical diagnosis (CMR 88.5:42.2%, P < 0.001) and presence of preoperative upper extremity weakness (57.7:32.3%, P = 0.02). Comparison between the C5P-LF and C5P-LP groups showed significant differences between incidence (28.9:4%), mean grade of weakness (2.1:3.5), accompanying nerve root symptoms (53.8:0%), recovery time (20.8:10.5 weeks), and incidence of incomplete recovery (15.4:0%).

CONCLUSION

C5P-LF patients showed higher incidence, more severe weakness, frequent involvement of multiple cervical nerve roots, and longer recovery time than C5P-LP patients. Preoperative clinical manifestation of CMR and preexisting upper extremity weakness were the related factors of C5 palsy.

LEVEL OF EVIDENCE

3.

Risk Factor Analysis for C5 Palsy after Double-Door Laminoplasty for Cervical Spondylotic Myelopathy

Study Design

A retrospective comparative study.

Purpose

To clarify the risk factors related to the development of postoperative C5 palsy through radiological studies after cervical double-door laminoplasty (DDL).

Overview of Literature

Although postoperative C5 palsy is generally considered to be the result of damage to the nerve root or segmental spinal cord, the associated pathology remains controversial.

Methods

A consecutive case series of 47 patients with cervical spondylotic myelopathy treated by DDL at our institution between April 2008 and April 2015 were reviewed. Postoperative C5 palsy occurred in 5 of 47 cases after DDL. We investigated 9 radiologic factors that have been reported to be risk factors for C5 palsy in various studies, and statistically examined these between the two groups of palsy and the non-palsy patients.

Results

We found a significant difference between patients with and without postoperative C5 palsy with regards to the posterior shift of spinal cord at C4/5 (p=0.008). The logistic regression analyses revealed posterior shift of the spinal cord at C4/5 (odds ratio, 12.066; p=0.029; 95% confidence interval, 1.295–112.378). For the other radiologic factors, there were no statistically significant differences between the two groups.

Conclusions

In the present study, we showed a significant difference in the posterior shift of the spinal cord at C4/5 between the palsy and the non-palsy groups, indicating that the "tethering phenomenon" was likely a greater risk factor for postoperative C5 palsy.

C5 nerve palsy after posterior reconstruction surgery: predictive risk factors of the incidence and critical range of correction for kyphosis

PURPOSE

It has been reported that the incidence of post-operative segmental nerve palsy, such as C5 palsy, is higher in posterior reconstruction surgery than in conventional laminoplasty. Correction of kyphosis may be related to such a complication. The aim of this study was to elucidate the risk factors of the incidence of post-operative C5 palsy, and the critical range of sagittal realignment in posterior instrumentation surgery.

METHODS

Eighty-eight patients (mean age 64.0 years) were involved. The types of the disease were; 33 spondylosis with kyphosis, 27 rheumatoid arthritis, 17 athetoid cerebral palsy and 11 others. The patients were divided into two groups; Group P: patients with post-operative C5 palsy, and Group NP: patients without C5 palsy. The correction angle of kyphosis, and pre-operative diameter of C4/5 foramen on CT were evaluated between the two groups. Multivariate logistic regression analysis was used to determine the critical range of realignment and the risk factors affecting the incidence of post-operative C5 palsy.

RESULTS

Seventeen (19.3 %) of the 88 patients developed C5 palsy. The correction angle of kyphosis in Group P (15.7°) was significantly larger than that in Group NP (4.5°). In Group P, pre-operative diameters of intervertebral foramen at C4/5 (3.2 mm) were significantly smaller than those in Group NP (4.1 mm). The multivariate analysis demonstrated that the risk factors were the correction angle and pre-operative diameter of the C4/5 intervertebral foramen. The logistic regression model showed a correction angle exceeding 20° was critical for developing the palsy when C4/5 foraminal diameter reaches 4.1 mm, and there is a higher risk when the C4/5 foraminal diameter is less than 2.7 mm regardless of any correction.

CONCLUSIONS

This study has indicated the risk factors of post-operative C5 palsy and the critical range of realignment of the cervical spine after posterior instrumented surgery.

Significant reduction in the incidence of C5 palsy after cervical laminoplasty using chilled irrigation water

Aims

The aim of this study was to determine whether chilled irrigation saline decreases the incidence of clinical upper limb palsy (ULP; a reduction of one grade or more on manual muscle testing; MMT), based on the idea that ULP results from thermal damage to the nerve roots by heat generated by friction during bone drilling.

Methods

Irrigation saline for drilling was used at room temperature (RT, 25.6°C) in open-door laminoplasty in 400 patients (RT group) and chilled to a mean temperature of 12.1°C during operations for 400 patients (low-temperature (LT) group). We assessed deltoid, biceps, and triceps brachii muscle strength by MMT. ULP occurring within two days post-operatively was categorised as early-onset palsy.

Results

The incidence of ULP (4.0% vs 9.5%, p = 0.003), especially early-onset palsy (1.0% vs 5.5%, p < 0.001), was significantly lower for the LT group than for the RT group. Multivariate analysis indicated that RT irrigation saline use, concomitant foraminotomy, and opened side were significant predictors for ULP.

Discussion

Using chilled irrigation saline during bone drilling significantly decreased the ULP incidence, particularly the early-onset type, and shortened the recovery period for ULP. Chilled irrigation saline can thus be recommended as a simple method for preventing ULP. Take home message: Chilled irrigation during laminoplasty reduces C5 palsy. Cite this article: Bone Joint J 2016;98-B:117–24.

Manual muscle test at C5 palsy onset predicts the likelihood of and time to C5 palsy resolution

The primary objective of this study was to identify time to and prognostic factors of C5 palsy resolution. All patients over a 7 year period who experienced C5 palsy following a posterior decompression and instrumented fusion surgery were retrospectively reviewed. C5 palsy resolution was defined as a recovery of deltoid muscle function equal to or greater than the preoperative condition as defined by the manual muscle test (MMT). Of the 511 patients who met the selection criteria, 8.6% (n=44) experienced C5 palsy. MMT information was available for 43 patients; 81.4% (n=35) had full resolution from their condition. Of the 35 patients who resolved, the median MMT score at onset was 3-. Following a discrete-time proportional hazards model, the hazards of C5 palsy resolution increased by 19% for every one-grade increase in MMT score at symptom onset (hazard ratio [HR]=1.19, p=0.005). Moreover, males displayed a 71% lower hazard of resolution than females (HR=0.29, p=0.003). Following an adjusted Kaplan-Meier analysis, the median time to C5 palsy resolution was between 6 months and 1 year. In a multiple linear regression, a lower MMT score at the onset of C5 palsy predicted a longer time to C5 palsy resolution (coefficient=-0.19, p=0.003). Time to C5 palsy onset was not statistically associated with hazards of palsy resolution (p=0.381) or time to resolution (p=0.121). A higher MMT score at the onset of C5 palsy statistically significantly predicted a higher chance of resolution and a shorter recovery time. Female sex was also associated with a higher hazard of resolution.

Delayed Bilateral C5 Palsy following Circumferential Decompression and Fusion in Patient with Cervical Spondylotic Myelopathy

C5 palsy is a common complication after cervical decompressive surgery, which have 0 to 30% complication rate. A 61-year-old female patient with cervical spondylotic myelopathy showed bilateral C5 palsy following circumferential decompression and fusion. Unexpectedly, bilateral C5 palsy was noted in different time points on postoperative day 2 and 8, respectively. Steroid injection and physical therapy were performed, and her motor function is recovering. Surgeons should make an effort to prevent possible C5 palsy when performing cervical decompression surgery.

A systematic review of clinical and surgical predictors of complications following surgery for degenerative cervical myelopathy

OBJECTIVE

Although generally safe and effective, surgery for the treatment of cervical spondylotic myelopathy (CSM) is associated with complications in 11%-38% of patients. Several predictors of postoperative complications have been proposed but few are used to detect high-risk patients. A standard approach to identifying "at-risk" patients would improve surgeons' ability to prevent and manage these complications. The authors aimed to compare the complication rates between various surgical procedures used to treat CSM and to identify patient-specific, clinical, imaging, and surgical predictors of complications.

METHODS

The authors conducted a systematic review of the literature and searched MEDLINE, MEDLINE in Process, EMBASE, and Cochrane Central Register of Controlled Trials from 1948 to September 2013. Cohort studies designed to evaluate predictors of complications and intervention studies conducted to compare different surgical approaches were included. Each article was critically appraised independently by 2 reviewers, and the evidence was synthesized according to the principles outlined by the Grading of Recommendation Assessment, Development and Evaluation (GRADE) Working Group.

RESULTS

A total of 5472 citations were retrieved. Of those, 60 studies met the inclusion criteria and were included in the review. These studies included 36 prognostic cohort studies and 28 comparative intervention studies. High evidence suggests that older patients are at a greater risk of perioperative complications. Based on low evidence, other clinical factors such as body mass index, smoking status, duration of symptoms, and baseline severity score, are not predictive of complications. With respect to surgical factors, low to moderate evidence suggests that estimated blood loss, surgical approach, and number of levels do not affect rates of complications. A longer operative duration (moderate evidence), however, is predictive of perioperative complications and a 2-stage surgery is related to an increased risk of major complications (high evidence). In terms of surgical techniques, higher rates of neck pain were found in patients undergoing laminoplasty compared with anterior spinal fusion (moderate evidence). In addition, with respect to laminoplasty techniques, there was a lower incidence of C-5 palsy in laminoplasty with concurrent foraminotomy compared with nonforaminotomy (low evidence).

CONCLUSIONS

The current review suggests that older patients are at a higher risk of perioperative complications. A longer operative duration and a 2-stage surgery both reflect increased case complexity and can indirectly predict perioperative complications.

Predicting Postoperative C5 Palsy Using Preoperative Spinal Cord Rotation

The development of C5 nerve palsy after cervical decompression surgery has been well documented. The goal of this study was to determine whether preoperative spinal cord rotation could be used as a predictor of C5 palsy in patients who underwent posterior cervical decompression at C4-C6. The authors reviewed the records of 72 patients who had posterior decompression and 77 patients who had anterior decompression. With the patients undergoing anterior decompression used as a control group, magnetic resonance imaging scans were analyzed for area of the spinal cord, anterior-posterior diameter, and cord rotation relative to the vertebral body. The rate of C5 palsy was 7.3%. Average degrees of rotation were 3.83°±2.47° and 3.45°±2.23° in the anterior and posterior groups, respectively. A statistically significant association was detected between degree of rotation and C5 palsy. Point-biserial correlations were 0.58 (P<.001) and 0.60 (P<.001) in the anterior and posterior groups, respectively. With a diagnostic cutoff of 6°, the sensitivity and specificity of identifying patients with C5 palsy in the posterior group were 0.67 (95% confidence interval, 0.24-0.94) and 0.95 (95% confidence interval, 0.86-0.98), respectively. The results suggested that preoperative spinal cord rotation may be a valid predictor of C5 nerve palsy after posterior cervical decompression. With mild rotation defined as less than 6°, moderate rotation as 6° to 10°, and severe rotation as greater than 10°, the prevalence of C5 palsy in the posterior group was 2 of 65 for mild rotation, 3 of 6 for moderate rotation, and 1 of 1 for severe rotation.

Can Multilevel Anterior Cervical Discectomy and Fusion Result in Decreased Lifting Capacity of the Shoulder?

OBJECTIVES

To investigate the upper-extremity abduction, and lifting limitations and associated factors after anterior cervical decompression and fusion.

METHODS

A total of 117 patients who underwent anterior cervical decompression and fusion for cervical spondylosis were assessed retrospectively. Their upper-extremity abduction and lifting capacity after operation and manual muscle test grade for deltoid muscle strength and its sensory status were recorded. In addition, spinal cord function (Japanese Orthopaedic Association and Neck Disability Index scores) and C4-5 intervertebral height (radiographs) were assessed. Finally, high signal and ossification of posterior longitudinal ligament were observed by T2 magnetic resonance imaging and computed tomography, respectively.

RESULTS

Seven individuals had a decrease in muscle strength, with 2 patients also exhibiting sensory defect. Six individuals had bilateral weakness of deltoid and biceps brachii and 1 of unilateral. After 8-16 months of follow-up, the abduction function and lift capacity were restored. The manual muscle test grade recovered to 5 and 4 degrees, respectively, in 6 and 1 patients. Two patients remained with sensory defect. The mean recovery time 19.7 days on average, and Japanese Orthopaedic Association scores significantly improved. Among the 117 patients, less than 2-level decompression showed upper-extremity function limitations in 1 of 67 (1.5%), whereas more than a 3-level decompression resulted in greater rate in 6 of 50 (12%), a significant difference (P < 0.05). No significant difference was obtained in C4-5 intervertebral heights, as well as for rates of C3-5 high signal area in magnetic resonance imaging.

CONCLUSIONS

The rate of upper-extremity abduction and lifting limitation after anterior cervical decompression and fusion is low, indicating a good prognosis after active treatment.

Inflammation Level after Decompression Surgery for a Rat Model of Chronic Severe Spinal Cord Compression and Effects on Ischemia-Reperfusion Injury

Delayed neurological deterioration in the absence of direct spinal cord insult following surgical decompression is a severe postoperative complication in patients with chronic severe spinal cord compression (SCC). The spinal cord ischemia-reperfusion injury (IRI) has been verified as a potential etiology of the complication. However, the exact pathophysiologic mechanisms of the decompression-related IRI remain to be defined. In this study, we developed a practical rat model of chronic severe SCC. To explore the underlying role of inflammation in decompression-related IRI, immunoreactivity of pro-inflammatory cytokines including tumor necrosis factor-alpha (TNF-α) and interleukin-1β (IL-1β) before and after decompression were measured. In addition, expression level of TNF-α and IL-1β was examined with Western blot. Immunohistochemical staining showed negative result in gray matters in the sham group and sham-decompression group. In the severe compression group, strong positive staining of TNF-α and IL-1β were found, suggesting a dramatic infiltration of inflammatory cells in gray matters. Furthermore, the severe compression group showed a significant increase in expression level of TNF-α and IL-1β as compared with the sham group (p < 0.05). In the severe compression-decompression group, both immunostaining and Western blot showed significant increase of TNF-α and IL-1β levels in the spinal cord compared with the severe compression group (p < 0.05). The results demonstrated that surgical decompression plays a stimulative role in inflammation through increasing the expression of inflammatory cytokines in the rat model of chronic severe SCC injury. Inflammation may be one of the important pathological mechanisms of decompression-related IRI of chronic ischemia.

Clinical and radiographic analysis of c5 palsy after anterior cervical decompression and fusion for cervical degenerative disease

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

To present the cases of 6 patients who developed C5 palsy after anterior decompression and discuss the mechanism of C5 palsy development, especially with respect to radiographic change.

SUMMARY OF BACKGROUND DATA

C5 palsy has been reported to be a major complication of both anterior and posterior decompression procedures. Although several mechanisms of injury have been proposed, few reports have been issued on C5 palsy after anterior decompression surgery.

METHODS

A retrospective medical record review was performed on 134 patients who underwent anterior decompression and fusion in our hospital from 2008 to 2011. C5 paralysis was defined as deterioration in muscle power of the deltoid or biceps brachii by at least 1 grade by manual muscle testing. Clinical features and radiologic parameters were evaluated to identify predisposing factors.

RESULTS

Six patients (4.3%) suffered postoperative paralysis in the upper extremities (C5 radiculopathy). C5 palsy did not occur in 30 patients with radiculopathy. Excluding patients with cervical radiculopathy, the rate of C5 palsies was 5.8% for myelopathy patients. Three of 76 (3.95'%) cervical spondylotic myelopathy cases, one of 6 (16.7%) cervical spondylotic radiculomyelopathy patients, and 2 of 22 (9%) patients with ossification of the posterior longitudinal ligament showed C5 palsy. In 2 of the 6, C5 palsy developed after anterior cervical corpectomy, in 3 patients after anterior cervical discectomy and plate fusion, and in 1 after a standalone cage. Two patients underwent reoperation for foraminal decompression. Of the 4 treated conservatively, 3 fully recovered and the other almost fully improved (grade 4). Of 2 patients treated surgically, 1 showed full improvements. The other had no improvement. Radiographic measurements of these 6 patients showed that lordosis at operated segments increased postoperatively (mean, 6 degrees), and that overall sagittal alignments of the cervical spine (C3-C7) also increased (mean, 8.2 degrees).

CONCLUSIONS

This study suggests that improved lordosis of the cervical spinal column can result in traction injury to the spinal cord and C5 nerve roots and that reoperation does not always produce good results. Methods of preventing and treating C5 palsy after anterior decompression and fusion require more evaluation.

Prevalence and distribution of thoracic and lumbar compressive lesions in cervical spondylotic myelopathy

Study Design

Retrospective cross-sectional study.

Purpose

This study analyzed the prevalence and distribution of horacic and lumbar compressive lesions in cervical spondylotic myelopathy as well as their relationships with cervical developmental spinal canal stenosis (DCS) by using whole-spine postmyelographic computed tomography.

Overview of Literature

There are few studies on missed compressive lesions of the spinal cord or cauda equina at the thoracolumbar level in cervical spondylotic myelopathy. Furthermore, the relationships between DCS, and the prevalence and distribution of thoracic and lumbar compressive lesions are unknown.

Methods

Eighty patients with symptomatic cervical spondylotic myelopathy were evaluated. Preoperative image data were obtained. Patients were classified as DCS or non-DCS (n=40 each) if their spinal canal longitudinal diameter was <12 mm at any level or ≥12 mm at all levels, respectively. Compressive lesions in the anterior and anteroposterior parts, ligamentum flavum ossification, posterior longitudinal ligament ossification, and spinal cord tumors at the thoracolumbar levels were analyzed.

Results

Compressive lesions in the anterior and anteroposterior parts were observed in 13 (16.3%) and 45 (56.3%) patients, respectively. Ligamentum flavum and posterior longitudinal ligament ossification were observed in 19 (23.8%) and 3 (3.8%) patients, respectively. No spinal cord tumors were observed. Thoracic and lumbar compressive lesions of various causes tended to be more common in DCS patients than non-DCS patients, although the difference was statistically insignificant.

Conclusions

Surveying compressive lesions and considering the thoracic and lumbar level in cervical spondylotic myelopathy in DCS patients are important for preventing unexpected neurological deterioration and predicting accurate neurological condition after cervical surgery.

Delayed neurological deterioration with an unknown cause subsequent to surgery for intraspinal meningiomas

Delayed neurological deterioration in the absence of direct cord insult following surgical decompression is rare, but severe post-operative complication occurs in chronically compressive spinal disorders. In the present study, the clinical medical records and radiological findings of 10 patients who underwent surgical removal of intraspinal meningiomas and then experienced delayed post-operative neurological deterioration were reviewed. The cases are presented with consideration of the possible underlying mechanisms. There were five male and five female patients, with a mean age of 46.8 years. The mean duration of illness from the onset of symptoms to diagnosis was 42.8 months. Seven tumors were located in the thoracic region and three in the cervical region of the spine. The tumors compressed the cord severely and gross total removal was achieved in all cases. Immediately subsequent to the surgery, all patients were able to move all extremities, but the onset of the neurological deterioration occurred at post-operative hours 3-8 in all cases (mean, 5 h post-surgery). In four cases, radiological examination revealed an area of high signal changes intrinsic to the cord on T2-weighted images, but without residual compression. The mean follow-up period was 49.6 months. Nine patients reported a marked recovery in status compared with the pre-operative presentation during the several weeks to months following surgery. The surgical removal of intraspinal meningiomas may lead to delayed and severe neurological deterioration in the post-operative period in the absence of direct mechanical cord insult. Ischemia-reperfusion injury may be one potential etiology of this deterioration. Recognition of the neurological deficit following surgical excision of intraspinal meningiomas may improve pre-operative patient counseling and merits further study for the determination of the precise pathophysiology.

Incidence and prognostic factors of c5 palsy: a clinical study of 1001 cases and review of the literature

BACKGROUND

C5 palsy is a known cause of postoperative deltoid weakness. Prognostic variables affecting the incidence of the palsy have been poorly understood.

OBJECTIVE

To determine the incidence and perioperative characteristics/predictors of C5 palsy after anterior vs posterior operations.

METHODS

All patients undergoing C4-5 operations for degenerative conditions were retrospectively reviewed over 21 years. Anterior operations included an anterior cervical discectomy and fusion (ACDF) or a corpectomy, whereas posterior operations included laminectomy and fusion (± foraminotomies).

RESULTS

Of the total 1001 operations, in 49.0% anterior and 51.0% posterior cases, there was an overall C5 palsy incidence of 5.2% (52 cases): 1.6% and 8.6%, respectively (P < .001). Of the 99 corpectomies, the palsy incidence of 4.0% was not only higher than ACDFs (1.0%), but also followed an upward trend with increasing corpectomy levels (P = .009). Of the 69 posterior and 83 anterior C4-5 foraminotomies, the incidence of C5 palsy was statistically higher in the posterior (14.5%) vs anterior (2.4%) cohort (P = .01). Multiple logistical regression identified older age as the strongest predictor of C5 palsy in the anterior (P = .02) and C4-5 foraminotomy in the posterior (P = .06) cohort. This condition improved within 3 to 6 months in 75% of patients in the anterior and 88.6% in the posterior cohort after a mean follow-up of 14.4 and 27.6 months, respectively.

CONCLUSION

In one of the largest cohorts on C5 palsy, we found in anterior operations an increasing number of corpectomy levels had a higher incidence of C5 palsy; however, older age was the strongest predictor of C5 palsy. In posterior operations, C4-5 foraminotomy carried the strongest correlation.

C5 palsy after posterior cervical decompression and fusion: cost and quality-of-life implications

BACKGROUND CONTEXT

C5 palsy is a debilitating postoperative complication of cervical decompression surgery. Although the prognosis is typically good, patients may be unable to perform basic activities of daily living, resulting in a decreased quality of life. No studies have investigated the quality-of-life and financial implications.

PURPOSE

The aim of the study was to determine the impact on quality-of-life and costs of C5 palsy after posterior cervical decompression and fusion (PCDF).

STUDY DESIGN/SETTING

A 2:1 matched retrospective cohort study was conducted at a single tertiary-care institution between 2007 and 2012.

PATIENT SAMPLE

Individuals who had undergone PCDF were included.

OUTCOME MEASURES

Self-reported: Euroqol-5 Dimensions quality-of-life survey. Physiologic: postoperative change in deltoid and biceps strength via manual muscle testing. Functional: cost of interventions and missed workdays postoperatively.

METHODS

Individuals with postoperative C5 palsy were matched to controls based on age, gender, body mass index, and diagnosis. Demographic, operative, postoperative, quality-of-life, and cost data were collected for both the C5 palsy and control groups, with 1-year follow-up.

RESULTS

We reviewed 245 patients who underwent PCDF and 17 were identified (6.9%) with C5 palsy and matched to 34 controls. No significant differences in demographic or operative characteristics were observed between groups. The C5 palsy group had a significantly reduced capacity for self-care in the immediate postoperative (2.0±0.71 vs. 1.2±0.4, p<.001) and long-term (1.6±0.6 vs. 1.2±0.4, p=.004) periods and a significantly reduced capacity for completion of usual activities (2.4±0.7 vs. 1.9±0.6, p=.014) compared with controls. Furthermore, the C5 group had a significantly greater cost of physical/occupational therapy, an increase of $2,078 ($4,386±$2,801 vs. $2,307±$1,907, p=.013). There were no significant differences between groups in the cost of hospital stay, surgery, or other direct or indirect costs. Overall, there was a significantly greater cost ($1,918) for the C5 palsy group compared with the control group ($7,584±$3,992 vs. $5,666±$2,359, respectively, p=.038).

CONCLUSIONS

This study represents the first quantification of the impact of C5 palsy on patients' quality of life and the associated costs for care. We found that C5 palsy adds a significant burden on patients' quality of life and presents a financial burden to the health-care system.