Cervical range of motion and patient-reported outcomes in patients undergoing surgical treatment for degenerative pathology of the subaxial cervical spine (C3–C7)

Abstract

Degenerative subaxial cervical (C3–C7) disease often requires surgery when conservative care fails, yet the relationship between post-operative cervical range of motion (ROM) and patient-reported outcomes is poorly defined. We evaluated post-operative ROM and its cross-sectional association with clinical outcomes. In a retrospective cohort with cross-sectional outcome assessment, 100 patients operated between 2015 and 2021 (anterior or posterior approach, with or without instrumentation) were assessed at a single follow-up visit. Neck-specific disability (Neck Disability Index, NDI), health-related quality of life (Short Form-12, SF-12) and cervical ROM (CROM device) were measured; pre-operative ROM was unavailable. Spearman and partial Spearman correlations (adjusted for age and comorbidity) and Mann–Whitney U comparisons were used. Median NDI was 16% (IQR 8–35), in the minimal-disability band; the SF-12 physical component (PCS-12, 40.2 ± 10.0) was below and the mental component (MCS-12, 47.6 ± 11.1) near the population norm of 50. NDI correlated negatively with ROM in all planes and with total ROM (ρ = −0.46, p < 0.001), and PCS-12 positively (axial rotation ρ = +0.52, p < 0.001); MCS-12 showed no significant association. Associations persisted after adjustment and in a Pearson sensitivity analysis. Exploratory comparisons, confounded by case-mix, showed greater axial rotation after the anterior approach. Greater post-operative ROM is associated with lower neck-specific disability and better physical quality of life, independent of age and comorbidity, but not with mental quality of life. The cross-sectional design precludes inference about the direction of these associations. Prospective studies with pre-operative ROM baselines are needed.