CERVICAL SPONDYLOTIC MYELOPATHY - SURGICAL RESULTS AND FACTORS AFFECTING PROGNOSIS

OBJECTIVE: A variety of factors may affect surgical outcome in patient s with cervical spondylotic myelopathy. The aim of this study is to de termine these factors on the basis of preoperative radiological and cl inical data. METHODS: To assess the factors affecting postoperative ou tcome after surgery for cervical spondylotic myelopathy, the clinical and radiological data of 27 patients with cervical spondylotic myelopa thy were reviewed. Functional and neurological statuses were assessed using the Japanese Orthopaedic Association (JOA) scale modified by Ben zel. In all patients, the effect of age, symptom duration, cervical cu rvature,presence or absence of preoperative high signal intensity with in the spinal cord as revealed by T2-weighted magnetic resonance imagi ng, and diameters of the spinal canal and vertebral body on pre- and p ostoperative neurological statuses were investigated. Plain radiograph s were obtained for all patients, magnetic resonance images for 21 pat ients (77.8%), computed tomographic scans for 13 patients (48.1%), mye lograms for 6 patients (22.2%), and computed tomographic myelograms fo r 4 patients (14.8%). There were five patients with a JOA score of 10, six patients with a JOA score of 11, six patients with a JOA score of 12, four patients with a JOA score of 13, four patients with a JOA sc ore of 14, one patient with a JOA score of 15, and one patient with a JOA score of 16. All patients underwent cervical laminectomies. The me an follow-up period was 54.1 months. The final neurological examinatio ns revealed improvement in the JOA scores of 85.1% of the patients. RE SULTS: Statistical analysis of all patients revealed mean JOA scores o f 12.185 +/- 1.618 and 14.370 +/- 2.15 before surgery and at final exa mination, respectively. The difference between the preoperative JOA sc ore and the final JOA score was determined to be statistically signifi cant (P < 0.0001). Statistical analyses also showed better neurologica l improvement in patients younger than 60 years and in patients with n ormal preoperative cervical lordosis. Although patients without preope rative high signal intensity of the spinal cord showed a better improv ement rate than did patients with preoperative high signal intensity, the determined difference was statistically insignificant. CONCLUSION: It can be concluded that age and abnormal cervical curvature predict less postoperative neurological improvement. The presence of preoperat ive high signal intensity within the spinal cord may also reflect less neurological improvement.