The gap between surgeon goal and achieved sagittal alignment in adult cervical spine deformity surgery

Surgeons failed to achieve their preoperative alignment goals by an average of 17.2 mm for C2-7 SVA, 10.3° for C2-7 sagittal Cobb angle, 15.6° for TS-CL, and 34.2 mm for C7-S1 SVA. The few factors identified that were associated with offset between goal and achieved alignment suggest that achievement of goal alignment was most challenging for more severe deformities. Further advancements are needed to enable more consistent translation of preoperative alignment goals into the operating room for adult CSD correction. Clinical trial registration no.: NCT01588054 (ClinicalTrials.gov).