Neurological recovery after surgical decompression in patients with cervical spondylotic myelopathy - a prospective study.

Cervical spondylotic myelopathy is a common clinical problem. No study has examined the pattern of neurological recovery after surgical decompression. We conducted a prospective study on the pattern of neurological recovery after surgical decompression in patients with cervical spondylotic myelopathy. Patients suffering from cervical spondylotic myelopathy and requiring surgical decompression from January 1995 to December 2000 were prospectively included. Upper limbs, lower limbs and sphincter functions were assessed using the Japanese Orthopaedic Association (JOA) score. Assessment was done before the operation, at 1 week, 2 weeks, 1 month, 3 months, 6 months, 1 year and then yearly after surgery. Results were analysed with the t-test. Differences with P-values less than 0.05 were regarded as statistically significant. Fifty-five patients were included. The average follow-up period was 53 months. Thirty-nine patients (71%) had neurological improvement after the operation with a mean recovery rate of 55%. The JOA score improved after surgery, reaching statistical significance at 3 months and a plateau at 6 months. Thirty-six patients (65%) had improvement of upper limb function. Twenty-four patients (44%) had improvement of lower limb function. Eleven patients (20%) had improvement of sphincter function. The recovery rate of upper limb function was 37%, of lower limb function was 23% and of sphincter function was 17%. Surgical decompression worked well in patients with cervical spondylotic myelopathy. Seventy-one percent of patients had neurological improvement after the operation. The neurological recovery reached a plateau at 6 months after the operation. The upper limb function had the best recovery, followed by lower limb and sphincter functions.