We studied 69 patients with cervical spondylotic myelopathy, and 33 patients with cervical ossification of the posterior longitudinal ligament with a mean age of 65.5 years and an average follow-up period of 4 years and 5 months. Clinical results were evaluated using the JOA score for cervical myelopathy and recovery rates using Hirabayashi's method. The overall mean recovery rate was 58%. There was no significant difference between recovery rate and age, duration of symptoms or preoperative JOA score.Moreover, we radiographically investigated changes in cervical alignment and rate of enlargement, antero-posterior movement, and instability in 50 cases.
