Bilateral phrenic nerve palsy as a complication of anterior decompression and fusion for cervical ossification of the posterior longitudinal ligament

Chronic intermittent tachycardia as a consequence of vagus nerve injury after anterior cervical discectomy and fusion: case report of a previously unreported complication

Background

The surgical approach of an anterior cervical discectomy and fusion (ACDF) navigates many important neurologic and vascular structures in the neck. More frequently reported complications are dysphagia, postoperative hematoma, cerebrospinal fluid leaks, and dysphonia.

Case description

This case report details an ACDF in a 49-year-old female with intractable neck pain and radicular symptoms. Following the procedure, she developed intermittent tachycardia at rest, which worsened with exertion.

Outcome

The cardiac workup was negative. A neck ultrasound demonstrated hypoechoic thickening of the vagus nerve, providing the diagnosis of vagus nerve injury. The patient's tachycardia has been managed with beta-blockers.

Conclusions

Although previously unreported, vagus nerve injury following ACDF is possible, causing sympathetic disruption, which can be managed with beta blockers.

Bilateral phrenic nerve palsy after posterior cervical decompression and fusion surgery: a rare event after surgery

INTRODUCTION

Delayed C5 weakness is a known entity in cervical spine surgery, although with varied clinical presentation and poorly understood mechanism of action. We describe the first case in the literature of a bilateral C5 palsy leading to bilateral phrenic nerve dysfunction following a posterior cervical decompression and fusion.

CASE REPORT

A 76-year-old male presented with low back pain and was diagnosed as myelopathic. On initial neurological examination, he could not ambulate without assistance and was unsteady on tandem gait. The initial cervical MRI and CT scan showed advanced multilevel degenerative changes of the cervical spine with severe cord compression and myelomalacia. The patient underwent C3-C6 posterior cervical decompression & fusion (PCDF). He awoke with his baseline examination without neurophysiological monitoring changes intraoperatively or C5 root EMG activity. Post-operative MRI of the cervical spine was performed and showed an excellent decompression. The patient was neurologically stable and discharged to a rehabilitation facility. Patient developed a delayed bilateral C5P on postoperative day (POD) 74. Delayed bilateral C5P and phrenic nerve damage was determined to cause this patient's dyspnea. PM&R consult recommended placement of diaphragmatic pacers. However, clinically his respiratory function, as well as motor deficits, have gradually improved.

CONCLUSION

Bilateral diaphragmatic paralysis, a severe complication of cervical spine surgery, may cause respiratory distress and upper limb weakness. C5P, the underlying cause, may arise from various factors. Early detection and management of diaphragmatic weakness with physical therapy and pacers are crucial, emphasizing the need for vigilance by healthcare professionals and surgeons.

Respiratory Compromise After Anterior Cervical Spine Surgery: Incidence, Subsequent Complications, and Independent Predictors

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Respiratory compromise (RC) is a rare but catastrophic complication of anterior cervical spine surgery (ACSS) commonly due to compressive fluid collections or generalized soft tissue swelling in the cervical spine. Established risk factors include operative duration, size of surgical exposure, myelopathy, among others. The purpose of this current study is to identify the incidence and clinical course of patients who develop RC, and identify independent predictors of RC in patients undergoing ACSS for cervical spondylosis.

METHODS

A large, prospectively-collected registry was used to identify patients undergoing ACSS for spondylosis. Patients with posterior cervical procedures were excluded. Baseline patient characteristics were compared using bivariate analysis, and multivariate analysis was employed to compare postoperative complications and identify independent predictors of RC.

RESULTS

298 of 52,270 patients developed RC (incidence 0.57%). Patients who developed RC had high rates of 30-day mortality (11.7%) and morbidity (75.8%), with unplanned reoperation and pneumonia the most common. The most common reason for reoperations were hematoma evacuation and tracheostomy. Independent patient-specific factors predictive of RC included increasing patient age, male gender, comorbidities such as chronic cardiac and respiratory disease, preoperative myelopathy, prolonged operative duration, and 2-level ACCFs.

CONCLUSION

This is among the largest cohorts of patients to develop RC after ACSS identified to-date and validates a range of independent predictors, many previously only described in case reports. These results are useful for taking preventive measures, identifying high risk patients for preoperative risk stratification, and for surgical co-management discussions with the anesthesiology team.

Risk factors for surgical complications in the management of ossification of the posterior longitudinal ligament

BACKGROUND CONTEXT

Ossification of the posterior longitudinal ligament (OPLL) is a progressive, debilitating disease most commonly affecting the cervical spine. When compared to other degenerative pathologies, OPLL procedures carry a significantly higher risk of complications owing to increased case complexity and technical difficulties. Most previous studies have focused on functional outcomes and few have reported on risk factors for postoperative complications in OPLL patients.

PURPOSE

To identify clinical and radiological risk factors of surgical complications following treatment for cervical OPLL STUDY DESIGN: Retrospective review PATIENT SAMPLE: One hundred thirty-one patients with cervical myelopathy secondary to OPLL who underwent surgical decompression with complete 2-year follow-up.

OUTCOME MEASURES

Surgical and medical postoperative complications were analyzed. Revision surgery rates and mortality rates were recorded.

METHODS

Clinical, surgical, and radiological characteristics were collected for each patient. Complications within 30 days were identified. Univariate and multivariate analysis were performed to identify risk factors for surgical complications.

RESULTS

There were 39 (29.8%) surgical complications in the cohort, which included C5 palsy (7.6%), dural tear (3.1%), surgical site infection (3.1%), and epidural hematoma (1.5%). 2-year revision and mortality rates were 4.6% and 2.3%, respectively. Univariate analysis revealed that blood loss ≥750mL (OR 3.42, p=0.028), operative duration ≥5.5 hours (OR 3.16, p=0.008), hill-type OPLL (OR 3.08, p=0.011), K-line (-) OPLL (OR 5.39, p<0.001), and presence of a double-layer sign (OR 3.79, p=0.002) were significant risk factors. In multivariate analysis, only hill-type OPLL (OR 2.61, p=0.048) and K-line (-) OPLL (OR 2.98, p=0.031) were found to be significant. Patients with both hill-type and K-line (-) OPLL had a 3.5 times risk of developing surgical complications (p=0.009).

CONCLUSIONS

Patients with OPLL have a higher risk of perioperative surgical complications if they had a hill-shaped OPLL and K-line (-) OPLL on preoperative imaging studies. To the best of the authors' knowledge, this study is the first to link hill-type and K-line (-) OPLL morphology as risk factors for perioperative surgical complications.

Phrenic nerve palsy after cervical laminectomy and fusion

Background

Outcome

Conclusions

A Review of Complication Rates for Anterior Cervical Diskectomy and Fusion (ACDF)

Background:

There are multiple complications reported for anterior cervical diskectomy and fusion (ACDF), one of the most common cervical spine operations performed in the US (e.g. estimated at 137,000 ACDF/year).

Methods:

Multiple studies analyzed the risks and complications rates attributed to ACDF.

Results:

In multiple studies, overall morbidity rates for ACDF varied from 13.2% to 19.3%. These included in descending order; dysphagia (1.7%-9.5%), postoperative hematoma (0.4%-5.6% (surgery required in 2.4% of 5.6%), with epidural hematoma 0.9%), exacerbation of myelopathy (0.2%-3.3%), symptomatic recurrent laryngeal nerve palsy (0.9%-3.1%), cerebrospinal fluid (CSF) leak (0.5%-1.7%), wound infection (0.1-0.9%-1.6%), increased radiculopathy (1.3%), Horner’s syndrome (0.06%-1.1%), respiratory insufficiency (1.1%), esophageal perforation (0.3%-0.9%, with a mortality rate of 0.1%), and instrument failure (0.1%-0.9%). There were just single case reports of an internal jugular veing occlusion and a phrenic nerve injury. Pseudarthrosis occurred in ACDF and was dependant on the number of levels fused; 0-4.3% (1-level), 24% (2-level), 42% (3 level) to 56% (4 levels). The reoperation rate for symptomatic pseudarthrosis was 11.1%. Readmission rates for ACDF ranged from 5.1% (30 days) to 7.7% (90 days postoperatively).

Conclusions:

Complications attributed to ACDF included; dysphagia, hematoma, worsening myelopathy, recurrent laryngeal nerve palsy, CSF leaks, wound infection, radiculopathy, Horner’s Syndrome, respiratory insufficiency, esophageal perforation, and instrument failure. There were just single case reports of an internal jugular vein thrombosis, and a phrenic nerve injury. As anticipated, pseudarthrosis rates increased with the number of ACDF levels, ranging from 0-4.3% for 1 level up to 56% for 4 level fusions.

Hemidiaphragmatic Paralysis Due to Cervical Spondylosis: A Case Report

Introduction

C4 radiculopathy due to cervical spondylosis has rarely been reported as a cause of hemidiaphragmatic paralysis.

Case Report

A 70-year-old man presented with hemidiaphragmatic paralysis due to right C3-C4 foraminal stenosis. The diagnosis was made preoperatively from findings on plain chest radiographs, respiratory function tests, and electrophysiologic tests. All the patient's test results and symptoms improved immediately after surgical treatment for cervical spondylosis.

Conclusions

Although it may be difficult to make a correct diagnosis based only on radiological findings at the cervical spine, we should be aware of the existence of this entity and pay close attention to chest radiographs.

Dyspnea as the Presenting Symptom of Cervical Spondylotic Myelopathy

Background  A case report of acute unilateral hemidiaphragm paralysis and resultant dyspnea due to cervical spondylotic myelopathy (CSM) is described.

Case Report  An 82-year-old man presented with a nonproductive cough, chest congestion, hoarseness, and shortness of breath on ambulation. The patient underwent cardiac catheterization, which revealed extensive stenosis of the major cardiac arteries. Subsequently, he underwent triple coronary artery bypass grafting. Despite the cardiac surgery, the patient's dyspnea did not improve. In addition, he developed new complaints of generalized weakness. Magnetic resonance and radiographic imaging of the cervical spine revealed extensive multilevel degenerative spondylosis with moderate to severe central canal narrowing from C2 to C7 and myelomalacia. The patient underwent C2–C6 laminectomy and instrumented fusion with local autograft. After surgery, the patient had gradual relief of dyspnea as well as improvement of strength. The dyspnea completely resolved.

Conclusion  The diagnosis of CSM as the cause of dyspnea is difficult to make. When unrelated cardiac or pulmonary disease coexists, the presenting symptoms of CSM may be subtle and must be actively sought. Signs and symptoms can vary widely and may include symptoms of intermittent neck pain or headache. Dyspnea may be related to unilateral diaphragm paralysis caused by CSM. This etiology of dyspnea should be considered in elderly patients who have other comorbidities that often obscure the diagnosis.

Diagnosis and Treatment of C4 Radiculopathy

STUDY DESIGN

Clinical case series.

OBJECTIVE

This study sought to clarify symptoms, diagnostic criteria, and treatment of C4 radiculopathy, and the role of diagnostic C4 root block in this entity.

SUMMARY OF BACKGROUND DATA

Although well understood cervical dermatomal/myotomal syndromes have been described for symptoms originating from impingement on the C2, C3, C5, C6, C7, and C8 roots, less has been written about the syndrome(s) associated with the C4 root.

METHODS

The senior author reviewed surgical records and describes his personal experience with the diagnosis and treatment of C4 radiculopathy.

RESULTS

A total of 712 procedures for cervical radiculopathy without myelopathy were reviewed. Among that cohort, 13 procedures involved the C4 root only and five procedures involved two level procedures including the C4 root. Patients described pain as involving the axial cervical region, paraspinal muscles, trapezius muscle, and interscapular region. No patient described pain over the anterior chest wall or radiating distal to the shoulder, one described pain over the medial clavicle. All patients who were offered surgery had a positive response to a diagnostic C4 transforaminal single nerve root block. Thirteen patients underwent posterior foraminotomy (five at two levels) and five patients underwent an anterior discectomy and fusion at C3-4. Mean Oswestry Disability Index score significantly declined; preoperative score 24.3 (range 14-29), postoperative score 9.7 (range 2-18; P = 0.003) at ≥3 months. Mean Short Form-36v2 score significantly increased; preoperative score 34.2 (range 20-40.2), postoperative score 73.7 (range 40.5-88.3, P = 0.001) at ≥3 months.

CONCLUSION

C4 root symptoms overlap those of the C3 and C5 roots and are very similar to facet mediated pain. Asymptomatic C4 foraminal stenosis may be a common imaging finding, it can be difficult to diagnose C4 radiculopathy clinically. Diagnostic C4 root block can make an accurate diagnosis and lead to successful surgical outcomes.

LEVEL OF EVIDENCE

4.

Subclinical respiratory dysfunction in chronic cervical cord compression: a pulmonary function test correlation

OBJECTIVE

Respiratory abnormalities are well documented in acute spinal cord injury; however, the literature available for respiratory dysfunction in chronic compressive myelopathy (CCM) is limited. Respiratory dysfunction in CCM is often subtle and subclinical. The authors studied the pattern of respiratory dysfunction in patients with chronic cord compression by using spirometry, and the clinical and surgical implications of this dysfunction. In this study they also attempted to address the postoperative respiratory function in these patients.

METHODS

A prospective study was done in 30 patients in whom cervical CCM due to either cervical spondylosis or ossification of the posterior longitudinal ligament (OPLL) was diagnosed. Thirty age-matched healthy volunteers were recruited as controls. None of the patients included in the study had any symptoms or signs of respiratory dysfunction. After clinical and radiological diagnosis, all patients underwent pulmonary function tests (PFTs) performed using a standardized Spirometry Kit Micro before and after surgery. The data were analyzed using Statistical Software SPSS version 13.0. Comparison between the 2 groups was done using the Student t-test. The Pearson correlation coefficient was used for PFT results and Nurick classification scores. A p value < 0.05 was considered significant.

RESULTS

Cervical spondylotic myelopathy (prolapsed intervertebral disc) was the predominant cause of compression (n = 21, 70%) followed by OPLL (n = 9, 30%). The average patient age was 45.06 years. Degenerative cervical spine disease has a relatively younger onset in the Indian population. The majority of the patients (n = 28, 93.3%) had compression at or above the C-5 level. Ten patients (33.3%) underwent an anterior approach and discectomy, 11 patients (36.7%) underwent decompressive laminectomy, and the remaining 9 underwent either corpectomy with fusion or laminoplasty.

The mean preoperative forced vital capacity (FVC) (65%) of the patients was significantly lower than that of the controls (88%) (p < 0.001). The mean postoperative FVC (73.7%) in the patients showed significant improvement compared with the preoperative values (p = 0.003). The mean postoperative FVC was still significantly lower than the control value (p = 0.002). The mean preoperative forced expiratory volume in 1 second (FEV1) (72%) of the patients was significantly lower than that of the controls (96%) (p < 0.001). The mean postoperative FEV1 (75.3%) in the cases showed no significant improvement compared with the preoperative values (p = 0.212). The mean postoperative FEV1 was still significantly lower than the control value (p < 0.001). The mean postoperative FEV1/FVC was not significantly different from the control value (p = 0.204). The mean postoperative peak expiratory flow rate was significantly lower than the control value (p = 0.01). The mean postoperative maximal voluntary ventilation was still significantly lower than the control value (p < 0.001). On correlating the FVC and Nurick scores using the Pearson correlation coefficient, a negative correlation was found.

CONCLUSIONS

There is subclinical respiratory dysfunction and significant impairment of various lung capacities in patients with CCM. The FVC showed significant improvement postoperatively. Respiratory function needs to be evaluated and monitored to avoid potential respiratory complications.

The characteristic clinical symptoms of C-4 radiculopathy caused by ossification of the posterior longitudinal ligament

Cervical radiculopathy of the C2-4 spinal nerves is a rare condition and is poorly documented in terms of clinical symptoms, hindering its detection during initial patient screening based on imaging diagnostics. The authors describe in detail the clinical symptoms and successful surgical treatment of a patient diagnosed with isolated C-4 radiculopathy. This 41-year-old man suffered from sleep disturbance because of pain behind the right ear, along the right clavicle, and at the back of his neck on the right side. The Jackson and Spurling tests were positive, with pain radiating to the area behind the patient's ear. Unlike in cases of radiculopathy involving the C5-8 spinal nerves, no loss of upper-extremity motor function was seen. Magnetic resonance imaging showed foraminal stenosis at the C3-4 level on the right side, and multiplanar reconstruction CT revealed a beak-type ossification of the posterior longitudinal ligament in the foraminal region at the same level. In the absence of intracranial lesions or spinal cord compressive lesions, the positive Jackson and Spurling tests and the C3-4 foraminal stenosis were indicative of isolated C-4 radiculopathy. Microscopic foraminotomy was performed at the C3-4 vertebral level and the ossified lesion was resected. The patient's symptoms completely resolved immediately after surgery. To the authors' knowledge, this report is the first to describe the symptomatic features of isolated C-4 radiculopathy, in a case in which the diagnosis has been confirmed by both radiological findings and surgical outcome. Based on this case study, the authors conclude that the characteristic symptoms of C-4 radiculopathy are the presence of pain behind the ear and in the clavicular region in the absence of upper-limb involvement.

Bilateral C5 motor paralysis following anterior cervical surgery—a case report

Numerous authors have reported C5 root palsies following posterior cervical surgery, and several mechanisms of injury have been proposed. Similar deficits after anterior cervical procedures are considered to occur less commonly. We report on a 48-year-old male who underwent multi-level anterior discectomy and fusion for cervical spondylotic myelopathy. Bilateral C5 nerve root deficits were noticed in the immediate postoperative period, and treated non-operatively. A postoperative magnetic resonance imaging (MRI) scan showed an increase in cervical lordosis accompanied by a posterior shifting of the spinal cord. Potential mechanisms of nerve root injury in this situation are discussed, and the literature on postoperative C5 root deficits is reviewed. The patient returned to his preoperative occupation as an operating room nurse 6 months following surgery, with complete neurologic recovery occurring over an 11-month period. C5 deficits following anterior cervical surgery occur more frequently than generally assumed. Improved lordosis and longitudinal lengthening of the cervical spinal column in multilevel anterior decompression and interbody fusion can paradoxically result in a traction injury to the spinal cord and C5 nerve roots.

Anterior corpectomy and fusion with fibular strut grafts for multilevel cervical myelopathy

OBJECT

The authors conducted a study to investigate the long-term results and postoperative complications of a new surgical technique, fibular strut graft-assisted anterior corpectomy and fusion for multilevel (> four) cervical myelopathy. Multilevel anterior corpectomy and subsequent strut graft placement is considered a challenging procedure because of complications relating to graft dislodgment, pseudarthrosis, greater operative duration, and increased blood loss.

METHODS

The study comprised 100 patients with cervical myelopathy who underwent anterior corpectomy and fusion and fibular strut graft placement at more than four disc space levels between 1989 and 1998. Single-screw fixation was used in conjunction with the autologous strut graft. Preoperative and postoperative plain radiographs, computerized tomography myelograms, and magnetic resonance images were obtained for assessment of fusion status. All complications and outcomes were analyzed based on clinical records to evaluate the results of the technique. There were no cases of graft dislodgment. The graft union rate was 85%. Analysis of clinical data showed that pseudarthrosis had no adverse effect on the clinical results. Adjacent-level disc degeneration occurred in 12% of patients, but in all cases the patients were asymptomatic. In 9% of cases C-5 palsy was observed but it recovered spontaneously. There were no infections and no case of neurological deterioration.

CONCLUSIONS

With this new graft technique, graft dislodgment, the major complication associated with strut graft surgery, was resolved completely. This simple technique involving single-screw fixation provided good results when used in conjunction with anterior decompression and strut graft fixation with a very low incidence of complications.

Iatrogenic-induced dysfunction of the neuromuscular respiratory system

In the presence of respiratory symptoms that are associated with alveolar hypoventilation or a restrictive ventilatory defect and in the absence of parenchymal or pleural abnormalities on the chest radiograph, iatrogenic causes must be evoked, exactly as they are in the presence of interstitial lung disease. In most cases, the anamnestic and clinical contexts provide a strong diagnostic presumption. It is important to establish carefully the mechanism of the observed disorders, using the currently available arsenal of diagnostic tools for clinical and prognostic reasons and from a medicolegal standpoint. It is necessary to evaluate precisely the clinical repercussions of the respiratory neuromuscular abnormality to serve as a basis for follow-up and to discuss therapeutic options in certain cases (eg, nocturnal ventilation to correct nocturnal hypoventilation due to diaphragmatic dysfunction, diaphragm plication to alleviate dyspnea after complete phrenic nerve destruction, phrenic nerve pacing), again in the perspective of medicolegal actions.