Endplate Degeneration and Intervertebral Vacuum Phenomenon Are Positively Correlated: A Retrospective Study in Patients Undergoing Lumbar Fusion Surgery.

Abstract

Retrospective cohort study. To analyze the correlation between intervertebral vacuum phenomenon (IVP) severity and total endplate damage score [total endplate score (TEPS)]. IVP severity and the TEPS are degenerative changes of the disc and endplate, respectively. We retrospectively analyzed a cohort of patients undergoing lumbar fusion surgery due to degenerative disease between 2013 and 2021. Computer tomography was used to classify the severity of the IVP at each lumbar level and as a combined lumbar score (Lumbar Vacuum Severity Scale). Magnetic resonance imaging was used to classify endplate degeneration by the TEPS. The correlation between the combined lumbar IVP and TEPS was analyzed through a multivariable regression model. A total of 317 patients were analyzed with a median age of 63 years (interquartile range: 55-71.2), and 48.9% (n = 155) were females. In all lumbar levels, the median TEPS was 4 (interquartile range: 2-8). The severity of the TEPS was significantly associated with an increased odds ratio (OR) of having more severe IVP (OR: 1.78, 95% CI: 1.62-1.95, P < 0.001). After adjusting for multiple confounders, this relationship remained significant (OR: 1.32, 95% CI: 1.17-1.49, P < 0.001). Other independent significant influences were age (OR: 1.07, 95% CI: 1.04-1.10, P < 0.001) and the Pfirrmann grade (OR: 7.44, 95% CI: 4.40-12.58, P < 0.001). The analysis of the relationship between the combined lumbar vacuum score and lumbar endplate score was significant, with a beta-coefficient (β) of 0.24 (95% CI: 0.20-0.28, P < 0.001). We found a significant correlation between IVP and TEPS in patients undergoing spine fusion surgery. These results support the theory that endplate damage could play a role in the pathogenesis of IVP.