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

Objective: To compare patient-reported outcomes measures (PROMs) following posterior cervical decompression and fusion (PCDF) based on changes in perioperative cervical sagittal alignment. Methods: 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. Results: 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. Conclusions: 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.