A novel method of C-VBQ score and CT-HU as risk predictors for cage subsidence after short level ACDF

We used a novel technique to measure subsidence after short-level anterior cervical discectomy and fusion (ACDF) with plate and screw fixation. And we aimed to evaluate cage subsidence by using cervical vertebral bone quality (C-VBQ) score and CT-HU. Quantitative assessment of vertebral bone quality was performed through two complementary methods: C-VBQ scoring and CT Hounsfield unit measurements, with their correlation established using Pearson’s analysis. The research methodology incorporated multiple statistical techniques, beginning with linear regression to examine demographic influences on C-VBQ values. For subsidence risk evaluation, all imaging datasets were rigorously compiled and subjected to multivariate regression analysis to identify significant contributing factors. The predictive validity of these factors was subsequently verified through ROC curve analysis, providing a robust assessment of their clinical utility. 112 patients who underwent short-level (≤ 2) ACDF were enrolled in this study, and 29 patients (25.89%) with cage subsidence were found. The subsidence group demonstrated significantly higher C-VBQ values (3.10 ± 0.22) compared to the non-subsidence cohort (2.70 ± 0.36, P < 0.001). Multivariate analysis identified the C-VBQ score as the sole independent predictor of cage subsidence following ACDF, achieving an 83.9% predictive accuracy. CT-HU value exhibited a significant inverse relationship with C-VBQ scores (P < 0.001). Univariate regression analysis identified age as the only parameter significantly correlated with C-VBQ values (P < 0.001). The inverse relationship between C-VBQ and CT-HU suggests its validity as a bone quality measure. Importantly, C-VBQ proved clinically valuable for identifying subsidence risk in 1–2 level ACDF procedures.