ObjectiveTo explore the self-influencing factors of curative effects of posterior cervical expansive single open-door laminoplasty multlevel cervical spondylotic myelopathy(CSM).

MethodsA total of 120 patients with multlevel CSM from December 2016 to December 2018 were treated with expansive laminoplasty, and followed up for 1 to 3 years.At the last follow-up, the patients were divided into the excellent group and poor group according to the the clinical efficacy evaluated by Japanese Orthopaedic Association(JOA) score.The general data such as gender, age and disease course of patients were collected, and the maximum diameter and average compression rate of pressure objects of the image data were calculated.The independent influencing factors of the curative effects between groups were investigated using the single factor and multi-factor analysis.

ResultsAmong 120 patients, the results of the last follow-up showed that the excellent in 34 cases, good in 61 cases, fair in 20 cases and poor in 5 cases were found, and the excellent and good rate of which was 79.17%.The differences of the disease course, age, maximum compression diameter, mean compression rate, spinal drift distance, preoperative Cobb angle and preoperative JOA score between two groups were statistically significant(P < 0.05 to P < 0.01).The differences of the sex and number of disease segments between two groups were not statistcially significant(P>0.05).The results of multivariate logistic regression analysis showed that the course of disease more than 2 years, maximum diameter of the pressure object more than 5 mm, spinal cord drift distance less than 2.6 mm, average compression rate more than 30% and preoperative JOA score less than 10 were the independent risk factor affecting the efficacy of expansive laminoplasty for multlevel CSM.

ConclusionsThe spinal enlargement is an effective method for treating multilevel CSM.The clinical efficacy is affected by its own factors such as longer course of disease, high degree of spinal cord compression and poor neurological function before surgery.