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

Optimal timing of referral for nerve transfer surgery for postoperative C5 palsy

OBJECTIVE

Cervical nerve 5 palsy can occur following surgery for cervical spine pathology. The prognosis of C5 palsy is generally favorable, and most patients recover useful function. However, some patients do not recover useful strength. Nerve transfers are a potential effective treatment of postoperative severe C5 palsy. This study aimed to further delineate the natural history of recovery from postoperative C5 palsy, determine whether lack of recovery at specific time points predicts poor recovery prognosis, and thereby determine a reasonable time point for referral to a complex peripheral nerve specialist.

METHODS

The authors conducted a retrospective review of 72 patients who underwent surgery for cervical spondylosis and stenosis complicated by C5 palsy. Medical Research Council (MRC) motor strength grades were recorded preoperatively; immediately postoperatively; at discharge; and at 2 weeks, 3 months, 6 months, and 12 months postoperatively. Univariate and multivariate logistic regression models were used to identify demographic and clinical risk factors associated with recovery of useful strength after severe C5 palsy.

RESULTS

The mean patient age was 62.5 years, and 36.1% of patients were female. Thirty patients (41.7%) experienced severe C5 palsy with less than antigravity strength (MRC grade 2 or less) at discharge. Twenty-one (70%) of these patients recovered useful strength (MRC grade 3 or greater) at 12 months postoperatively, and 9 patients (30%) did not recover useful strength at 12 months. Of those patients with persistent severe C5 palsy at 3 months postoperatively, 50% recovered useful strength at 12 months. Of those patients with persistent severe C5 palsy at 6 months postoperatively, 25% recovered useful strength at 12 months. No patient with MRC grade 0 or 1 strength at 6 months postoperatively recovered useful strength. A history of diabetes was associated with the occurrence of severe C5 palsy. On multivariate analysis, female sex was associated with recovery of useful strength.

CONCLUSIONS

Most patients with severe C5 palsy recover useful strength in their C5 myotome within 12 months of onset. However, at 3 months postoperatively, patients with persistent severe C5 palsy had only a 50% chance of recovering useful strength by 12 months. Lack of recovery of useful strength at 3 months postoperatively is a reasonable time point for referral to a complex peripheral nerve center to establish care and to determine candidacy for nerve transfer surgery if severe C5 palsy persists.

Comparison of Complications between Anterior Cervical Diskectomy and Fusion versus Anterior Cervical Corpectomy and Fusion in Two- and Three-Level Cervical Spondylotic Myelopathy: A Meta-analysis

BACKGROUND

 In this study, we systematically analyze the differences in complications between anterior cervical diskectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) in two- and three-level cervical spondylotic myelopathy (CSM).

METHODS

 We performed a systematic search in MEDLINE, EMBASE, PubMed, Web of Science, Cochrane databases, Chinese Biomedical Literature Database, CNKI, and Wan Fang Data for all relevant studies. All statistical analyses were performed using Review Manager version 5.3.

RESULTS

 A total of 11 articles with 849 study subjects were included, with 474 patients in the ACDF group and 375 patients in the ACCF group. The results of the meta-analysis showed that in C5 palsy (odds ratio [OR]: 0.41; 95% confidence interval [CI]: 0.16-1.06), pseudarthrosis (OR: 1.07; 95% CI: 0.23-5.07), dysphagia (OR: 1.06; 95% CI: 0.60-1.86), infection (OR: 0.41; 95% CI: 0.16-1.09), cerebrospinal fluid leakage (OR: 1.21; 95% CI: 0.39-3.73), graft dislodgment (OR: 0.28; 95% CI: 0.06-1.37), and hematoma (OR: 0.32; 95% CI: 0.06-1.83), there are no significant differences between the ACDF and ACCF groups, whereas total complication (OR: 0.50; 95% CI: 0.31-0.80) showed that the ACDF group had a significantly lower morbidity than the ACCF group. Furthermore, the three-level subgroup of ACDF had significantly better results in C5 palsy (OR: 0.31; 95% CI: 0.11-0.88), infection (OR: 0.22; 95% CI: 0.05-0.94), graft dislodgment (OR: 0.07; 95% CI: 0.01-0.40), and total complication (OR: 0.37; 95% CI: 0.23-0.60) compared with the ACCF subgroup.

CONCLUSION

 In general, postoperative pseudarthrosis, dysphagia, cerebrospinal fluid leakage, hematoma, C5 palsy, infection, and graft dislodgment did not differ significantly between the two groups. Total complication was significantly less in the ACDF group compared to the ACCF group. In the three-level subgroup, the morbidity of C5 palsy, infection, and graft dislodgment was significantly lower in ACDF than in ACCF.

The F2RaD Score: A Novel Prediction Score and Calculator Tool to Identify Patients at Risk of Postoperative C5 Palsy

BACKGROUND

Postoperative C5 palsy is a debilitating complication following posterior cervical decompression.

OBJECTIVE

To create a simple clinical risk score predicting the occurrence of C5 palsy

METHODS

We retrospectively reviewed all patients who underwent posterior cervical decompressions between 2007 and 2017. Data was randomly split into training and validation datasets. Multivariable analysis was performed to construct the model from the training dataset. A scoring system was developed based on the model coefficients and a web-based calculator was deployed.

RESULTS

The cohort consisted of 415 patients, of which 65 (16%) developed C5 palsy. The optimal model consisted of: mean C4/5 foraminal diameter (odds ratio [OR] = 9.1 for lowest quartile compared to highest quartile), preoperative C5 radiculopathy (OR = 3.5), and dexterity loss (OR = 2.9). The receiver operating characteristic yielded an area under the curve of 0.757 and 0.706 in the training and validation datasets, respectively. Every characteristic was worth 1 point except the lowest quartile of mean C4/5 foraminal diameter, which was worth 2 points, and the factors were summarized by the acronym F2RaD. The median predicted probability of C5 palsy increased from 2% in patients with a score of 0 to 70% in patients with a score of 4. The calculator can be accessed on https://jhuspine2.shinyapps.io/FRADscore/.

CONCLUSION

This study yielded a simplified scoring system and clinical calculator that predicts the occurrence of C5 palsy. Individualized risk prediction for patients may facilitate better understanding of the risks and benefits for an operation, and better prepare them for this possible adverse outcome. Furthermore, modifying the surgical plan in high-risk patients may possibly improve outcomes.