The Impact of Cervical Curvature on Laminoplasty for Cervical Spondylotic Myelopathy

Introduction: To explore the mid-term efficacy and sagittal balance of cervical posterior laminoplasty (LAMP) in patients with degenerative cervical spondylotic myelopathy (CSM) with different degrees of cervical curvature

Methods: Ninety-seven patients with CSM who underwent LAMP treatment in our hospital were retrospectively analyzed. The kyphosis angle was defined as negative, while the cervical lordosis angle was considered positive. Based on the standard lateral radiographs of the cervical spine, measurements of the C2 slope, C7 slope, C2-C7 curvature, segmental kyphosis angle, and sagittal vertical axis of C2-C7 were taken both before and two years after the operation. Additionally, VAS scores for neck pain, JOA scores, and NDI were recorded at both time points.

Results: Among the three groups, the average NDI improvement rate in the severe kyphotic group was 60±9%, which was significantly lower than that in the lordotic degeneration group 67±9% and the mild kyphotic degeneration group 67±7% (P < 0.05). In the mild cervical kyphosis group, the mean segmental kyphosis angle decreased significantly from 7.64±3.08° before surgery to 3.06±1.57° after surgery (P < 0.05). However, the average segmental kyphosis angle remained relatively unchanged in the severe cervical kyphosis group.

Conclusion : The mid-term follow-up of CSM patients who underwent LAMP indicated that patients with cervical lordotic degeneration and mild kyphotic deformity were suitable candidates for this procedure, whereas patients with severe cervical kyphosis were not recommended to be treated with LAMP alone.