Background: Reciprocal alterations in cervical and global spine alignment are widely acknowledged. However, there is limited evidence of the changes in global spine alignment that occur after cervical lordosis is restored following anterior cervical discectomy and fusion (ACDF). 
Objectives: This study aims to investigate the effect of ACDF on global spine alignment. 
Methods: This retrospective study comprised 32 patients (mean age 46±10 years) who underwent ACDF for cervical disc herniation. Cervical alignment, local and global spine alignment, and pelvic parameters were measured on the preoperative and three-month postoperative EOS® images. 
Results: All spinal indices were altered after the operation, and this difference was statistically significant in all cases except for thoracic kyphosis. Three months after the surgery, total cervical lordosis correction was greater in patients with a single fusion level (P<0.001); however, local cervical lordosis correction was significantly higher in patients with more than one fusion level (P<0.001). Pelvic tilt change was significantly higher in cases with multiple fusion levels (P=0.043).
Conclusion: Regarding the number of fusion levels in patients undergoing ACDF, restoration of global and local cervical lordosis changes global spinal alignment.