BACKGROUND
This study investigated the association between postoperative C2-7 sagittal vertical axis (SVA) and axial symptoms after posterior cervical surgery, and explored whether this association differed between open-door expansive laminoplasty (LP) and total laminectomy with fusion (LF).
MATERIAL AND METHODS
This single-center retrospective cohort study included 64 patients with MCSM, including 33 in the LP group and 31 in the LF group, after propensity score–based trimming and covariate balance assessment. Cervical sagittal parameters, range of motion (ROM), and clinical outcomes were evaluated preoperatively and during 2 to 3 years of follow-up. Logistic regression and receiver operating characteristic (ROC) analyses were performed as exploratory analyses.
RESULTS
The incidence of axial symptoms did not differ significantly between the LP and LF groups (21.2% vs 32.3%, P=0.40). Both groups showed significant improvements in visual analog scale, Japanese Orthopaedic Association, and Neck Disability Index scores. Compared with LP, LF was associated with greater postoperative changes in C2-7 SVA, C2-7 Cobb angle, C7 slope, and ROM reduction. Postoperative C2-7 SVA was associated with AS. Exploratory ROC analyses suggested optimal C2-7 SVA cutoffs of 3.46 cm in the LP group and 3.10 cm in the LF group. The group × C2-7 SVA interaction was statistically significant but based on a small number of axial symptom events.
CONCLUSIONS
Postoperative C2-7 SVA may be associated with axial symptoms, and this association appeared stronger after LF in this small cohort. All ROC-derived thresholds and interaction findings are exploratory, hypothesis-generating, and not clinically actionable, pending validation in larger prospective studies.

Keywords: Cervical Vertebrae; Neurosurgery; Spinal Cord Compression