Clinical and radiographic outcome of unilateral open-door laminoplasty with alternative levels centerpiece mini-plate fixation for cervical compressive myelopathy: a five-year follow-up study.

INTRODUCTION

To evaluate the five year clinical and radiographic outcome of unilateral open-door laminoplasty with alternative levels centerpiece mini-plate fixation for cervical compressive myelopathy.

METHODS

From August 2009 to June 2010, 56 patients with cervical compressive myelopathy underwent unilateral open-door laminoplasty with alternative levels centerpiece mini-plate fixation with a mean age of 64.8 years. Clinical results were investigated including Japanese Orthopedic Association (JOA) scores, Neck Dysfunction Index (NDI), occurrences of complications and neurological deterioration. Radiographic results including cervical alignments, cervical range of motion (ROM), spinal canal enlargement and spinal cord decompression were assessed on X-ray, three-dimensional CT and MRI.

RESULTS

The mean follow-up period was 59.2 months (range 53∼64 months), and all patients achieved osseous fusion at hinge side at an average of 6.8 months after operation. The average cost from admission to discharge is $9817.9. Compared to previous all-level fixation, the cost decreased nearly 40 %. During the follow-up, all patients showed a significant improvement in the JOA score and NDI score. A 23.2 % incidence of axial neck pain were also observed; Significant enlargement of the spinal canal and spinal cord drift was achieved and well maintained, overall cervical ROM decreased by 27.1 % (mean 12.9° loss) at the final follow-up and cervical lordosis decreased slightly in all patients without statistic difference. No instrumentation failure or lamina reclosure was observed in our study. Comparing mini-plate segments and suture segments, the mean AP diameter and Pavlov's ratio at the final follow-up showed no statistic difference, only open angle at the final follow-up showed significant decrease.

CONCLUSIONS

Unilateral open-door laminoplasty with alternative levels centerpiece mini-plate fixation is a safe, effective and economical surgical method for cervical compressive myelopathy and the five year result is satisfactory.