Improved Sagittal Alignment Is Associated with Early Postoperative Neck Disability and Pain-Related Patient-Reported Outcomes Following Posterior Cervical Decompression and Fusion for Myelopathy

Abstract

To compare patient-reported outcomes measures (PROMs) following posterior cervical decompression and fusion (PCDF) based on changes in perioperative cervical sagittal alignment. We reviewed patients who underwent PCDF from C2 to T2 between the years 2015 and 2020. C2 sagittal vertical axis (SVA) and C2-C7 lordosis were assessed preoperatively and 1-year postoperatively. Neck Disability Index (NDI) and visual analog scale (VAS) Neck scores were collected preoperatively, 3 months' postoperatively, and 1-year postoperatively. PROMs were compared based on perioperative radiographic parameters. Eighty-five patients were included in this study. Patients with preoperative C2 SVA <40 mm had a larger improvement in VAS Neck pain scores at 3 months' postoperatively (-4.9 vs. -3.0, P= 0.03) and a larger decrease in NDI scores at 1-year postoperatively (7.2 vs. 3.1, P= 0.04) than patients with C2 SVA ≥40 mm. Patients with postoperative C2 SVA <40 mm demonstrated lower VAS Neck pain scores at 3 months' postoperatively (2.0 vs. 3.4, P= 0.049). The cohort of patients with a decrease of C2 SVA by ≥5 mm demonstrated lower NDI at 3 months' postoperatively but not at 1-year postoperatively in comparison with patients whose C2 SVA increased or remained unchanged (11.7 vs. 23.8 vs. 18.2; P < 0.001). Patients in whom both C2 SVA and C2-C7 lordosis improved demonstrated superior NDI (P < 0.001) and VAS Neck (P= 0.007) at 3 months' but not at 1-year postoperatively. In a uniform cohort of patients undergoing PCDF from C2 to T2, improvements in C2 SVA and C2-C7 lordosis were associated with improved early postoperative PROMs.