BACKGROUND AND PURPOSE

In the classic Hirabayashi procedure, the lamina door is tethered open by sutures between the spinous process and facet capsule or para-vertebral muscle. Our early experiences showed, however, that the loosened sutures result in dislodgement and reclosure of the lifted lamina. We present a modified method to ensure secure fixation and prevent restenosis due to hinge closure.

PATIENTS AND METHODS

12 patients with cervical spondylotic myelopathy underwent unilateral open-door laminoplasty using suture anchor fixation between 2000 and 2004. The sutures were tied and fixed onto the holed lateral mass screws, instead of using the conventional suture technique. We used radiography, MRI, and CT for imaging studies. The Nurick score was used to assess severity of myelopathy, and the Japanese Orthopedic Association (JOA) score was used to evaluate clinical outcomes before surgery and at the last follow-up visit.

RESULTS

All patients experienced functional improvement of at least 1 Nurick score after surgery. The JOA score for the 12 patients increased significantly from 6.9 (SD 3.0) before surgery to 13 (SD 1.6) at final follow-up. Postoperative radiography and CT showed increased sagittal diameter and canal expansion. Average preoperative and postoperative ranges of motion for the cervical spine were 48 (SD 4.6) and 36 (SD 2.7), respectively. No neurological deterioration due to hinge reclosure and no major surgery-related complications were observed during the follow-up period.

INTERPRETATION

Open-door laminoplasty using suture anchor fixation effectively maintains expansion of the spinal canal and resists closure while preserving alignment and flexibility. This modified technique is easy to use, has a low complication rate, and provides marked functional improvement for patients with cervical spondylolytic myelopathy.