Safety and stability of open-door cervical expansive laminoplasty

Abstract

Cervical expansive laminoplasty has been utilized for over 20 years. This retrospective analysis investigated the safety and incidence of postoperative instability of patients undergoing a modified expansive laminoplasty. One hundred five patients underwent a modified cervical expansive laminoplasty and had at least a 6-month follow-up. These 105 patients were followed for a mean of 18.6 months (range 6-89 months). All patients remained in a rigid cervical collar for 8-12 weeks after the laminoplasty. Postoperative cervical plain radiographs were obtained on postoperative day 1, an average of 9.6 weeks postoperatively (range 8-12 weeks) and an average of 10.1 months (range 6-12 months) postoperatively. Thirty-five patients underwent further radiographs >18 months postoperatively. Laminoplasty was performed in 82 patients with progressive cervical spondylotic myelopathy, 4 patients with ossification of the posterior longitudinal ligament, 7 patients for posterior approach to a cervical neoplasm, and 12 patients for early posttraumatic decompression. The canal/vertebral body ratio showed a significant increase from 0.78 to 1.02 (paired t test, p < 0.001). Postoperatively, no incidence of graft dislodgement or segmental instability was diagnosed in any patient. Modified open-door expansive laminoplasty is an effective way of expanding the spinal canal. Its associated low incidence of postoperative instability and kyphotic deformity should make this procedure a desirable substitute for cervical laminectomy under many circumstances.