Analysis of myelomalacia and posterior longitudinal Ligament ossification as prognostic factors in patients with cervical spondylotic myelopathy submitted to laminoplasty

Background: Cervical spondylotic myelopathy is a degenerative disease of the intervertebral disc and vertebral body of the spine that causes cervical spinal cord injury due to central vertebral canal stenosis. Its prevalence is higher in the elderly. Treatment is usually surgical when the spinal cord is affected either clinically with pyramidal release or radiologically with the altered spinal cord. Objective: The rationale of this study is to analyze the myelomalacia and the ossification of posterior longitudinal ligament as prognostic factors in the postoperative evolution of patients with cervical canal compression who underwent laminoplasty by open-door or french-door techniques. Methods: We performed a retrospective analysis of 18 surgical cases of spondylotic cervical myelopathy of the same senior neurosurgeon, using the chi-square test to analyze prognostic factors for patients’ postoperative evolution in the Nurick scale, after open-door or french-door laminoplasty. Results: The comparison between pre and postoperative showed an improvement of 71.43% of cases that did not have ligament ossification compared to 45.45% of cases that presented posterior longitudinal ligament ossification. Also, there was a better prognosis in patients without myelomalacia, as 71.43% of them improved their condition against only 45.45% improvement in those with myelomalacia. Conclusion: There is a need for further studies with larger samples to expressively prove that the presence of longitudinal ligament ossification and the previous presence of myelomalacia are factors of worse prognosis in the postoperative evolution of patients with cervical spondylotic myelopathy submitted to laminoplasty.

Analysis of risk factors for C5 nerve root paralysis after posterior cervical decompression

Background C5 nerve root paralysis is a nonnegligible complication after posterior cervical spine surgery (PCSS). The cause of its occurrence remains controversial. The purpose of this study was to analyse the incidence of and risk factors for C5 nerve root paralysis after posterior cervical decompression. Methods We retrospectively analysed the clinical data of 640 patients who underwent PCSS in the Department of Orthopaedics, Affiliated Hospital of Qingdao University from September 2013 to September 2019. According to the status of C5 nerve root paralysis after surgery, all patients were divided into paralysis and normal groups. Univariate and multivariate analyses were used to determine the independent risk factors for C5 nerve root paralysis. A receiver operating characteristic (ROC) curve was used to demonstrate the discrimination of all independent risk factors. Results Multivariate logistic regression analysis revealed that male sex, preoperative cervical spine curvature, posterior longitudinal ligament ossification, and preoperative C4/5 spinal cord hyperintensity were independent risk factors for paralysis, whereas the width of the intervertebral foramina was an independent protective factor for paralysis. The area under the curve (AUC) values of the T2 signal change at C4-C5, sex, cervical foramina width, curvature and posterior longitudinal ligament ossification were 0.706, 0.633, 0.617, 0.637, and 0.569, respectively. Conclusions Male patients with C4-C5 intervertebral foramina stenosis, preoperative C4-C5 spinal cord T2 high signal, combined with OPLL, and higher preoperative cervical spine curvature are more likely to develop C5 nerve root paralysis after surgery. Among the above five risk factors, T2 hyperintensity change in C4-C5 exhibits the highest correlation with C5 paralysis and strong diagnostic power. It seems necessary to inform patients who have had cervical spine T2 hyperintensity before surgery of C5 nerve root paralysis after surgery, especially those with altered spinal cord T2 signals in the C4-C5 segment.