Retrospective Analysis Of Operative Treatment Of Cervical Spondylotic Myelopathy

Objective: To investigate the surgical outcome of cervical spondylotic myelopathy (CSM)and the relationship between the treatment result and influential factors.Methods:Fourty-one patients ( 30males and 11 females) with cervical spondylotic myelopathy who underwent operative treatment between June 1999 and April 2006 in First Affiliated Hospital of SuZhou university were included in this study. Their mean age at surgery was 49.5 years, ranging from 42 to 74 years. The follow-up period ranged from l2 months to more than 7 years(mean 28 months).The mean duration of symptoms was 10.3 months(ranging from 1 months to 5 years). The study comprised 12 laminectomy patients, 24 Anterior cervical discectomy and fusion patients and 5Anterior cervical subtotal corpectomy and fusion patients.The preoperative, postoperative and the last follow-up plain lateral cervical spine radiographs of 41 patients were evaluated. We measured the cervical lordosis, cobb angle and the height of the fusion segments(to take the place of disk space height). Acording to Japanese Orthopaedics Association 17 scores method for the cervical spondylotic myelopathy and the functional grading system of Nurick, the neurological function of all patients was evaluated respectively . Logistic regression analysis for correlated data using generalized estimating equations and single factor analysis was performed to study the relation between possible predictor variables and the occurrence of high-signal abnormalities on T2-weighted images and the surgical outcome of anterior decompression with spinal fusion(ASF) .Results: The mean JOA score before surgery was 8.54±2.96 points, and the mean preoperative Nurick score was 3.24±0.92.The mean postoperative JOA score was 14.17±2.59 points, and the mean postoperative Nurick score was 1.46±1.31. The JOA recovery rate among the total patients was classified as exellent in 18,good in13,fair in 7,poor in 3,the excellent and good rate was 75.61%.The postoperative JOA score and Nurick Score improved significantly,and the differences were significant(p<0.05). and the cervical lordosis,the cobb angle and the height of the anterior and posterior border of the fusion segments (HAB,HPB) increased significantly (p<0.05).Only the number of treated level seemed to be predictive for the surgical outcome of ASF (B=-1.623,p=0.051).The cases with a high-signal abnormalities on T2-weighted images had worse surgical outcome(B=-0.043,p=0.051),and the abnormalities was related to osseous spinal stenosis(B=3.032,p=0.003). There was no statistic difference between anterior and posterior surgery outcome for those with osseous spinal stenosis(p=0.526).CONCLUSION: Both anterior and posterior surgery are effective for CSM. There is no statistic difference between ASF and laminoplasty. The number of treated level seemed to be predictive for the surgical outcome of ASF.A high-signal abnormalities on T2-weighted images which was related to osseous spinal stenosis was predictive for the surgical outcome of CSM.