Abstract
For treatment of cervical spondylotic myelopathy (CSM), various posterior decompression procedures can be adopted, such as Z-shaped laminoplasty, expansive open-door laminoplasty, and spinous process-splitting laminectomy. We have conducted expansive open-door laminoplasty as the first treatment of choice in 168 CSM patients since 2001, even in the presence of spondylolisthesis. However, some researchers have described postoperative instability in such cases with regard to the angle of cervical lordosis, range of motion, and slippage angle of the cervical spine, although little has been reported regarding the slippage distance of the cervical spine after surgery. In this study, we evaluated 6 patients showing CSM with a slippage distance of 3.5mm or greater on X-ray images, treated by expansive open-door laminoplasty without internal fixation devices, who were followed -up for more than 5years (range: 5yr 9mo to 9yr). Their severe slippage distance before surgery (3.9±0.4mm) had not worsened at the final follow-up (3.6±0.8mm) (p=0.17). Other aspects were significantly reduced, including the slippage angle, range of motion of the cervical spine, and dynamic antero-posterior diameter of the cervical spinal canal. Expansive open-door laminoplasty is considered effective for surgical management of patients with CSM, even when accompanied by spondylolisthesis.
