Effect of Cervical Sagittal Balance on Laminoplasty in Patients With Cervical Myelopathy.

STUDY DESIGN: Retrospective clinical study.

OBJECTIVE: We evaluated the relationship between cervical sagittal alignment parameters and clinical status in patients with cervical myelopathy and analyzed the effect of cervical sagittal balance on cervical laminoplasty.

METHODS: Patients with cervical myelopathy (n = 110) who underwent laminoplasty were included in this study. The relationship between cervical sagittal alignment parameters and clinical status was evaluated. The changes in radiographic cervical sagittal parameters and clinical status 2 years after surgery were compared between patients with preoperative C2-7 SVA ≥35 mm (group A) and those with preoperative C2-7 SVA <35 mm (group B).

RESULTS: Preoperatively, C2-7 SVA had no correlation with defined health-related quality of life evaluation scores. At 2-year follow-up, the improvement in SF-36 physical component summary was significantly lower in group A than in group B. The postoperative change of C2-7 SVA did not significantly differ in 2 groups. Patients in group A maintained cervical regional balance after laminoplasty but experienced extensive postoperative neck pain.

CONCLUSIONS: Our patients with a C2-7 SVA of ≥35 mm maintained cervical regional balance after laminoplasty and their improvement in myelopathy was equivalent to that in patients with a C2-7 SVA of <35 mm. However, the patents with a C2-7 SVA of ≥35 mm experienced severe postoperative neck pain. C2-7 SVA is a parameter worth considering because it can lead to poor QOL and axial neck pain after laminoplasty.