Canal-expansive laminoplasty in 83 patients with cervical myelopathy. A comparative study of three different procedures.

We have reviewed 83 patients who had undergone canal-expansive laminoplasty for the treatment of cervical myelopathy between 1982 and 1991. The procedures used for laminoplasty were a Z-plasty in 35 patients, unilateral laminoplasty in 19, and sagittal splitting of the spinous processes in 29. At an average follow-up of more than two years and five months, there were no significant differences in clinical results among the three operations, and excellent or good results were obtained in more than 70% of the patients. However, Z-plasty was the least preferable because this procedure had the longest operating time and the greatest intraoperative blood loss. The sagittal splitting procedure is recommended in routine laminoplasty in order to avoid complications at the site of osteotomy, and to allow simultaneous posterior fusion to be easily performed.