Title: Prevalence，Distribution Characteristic and Risk Factors of Lumbar Vertebral Axial rotation in Patients with Lumbar Disc Herniation：A Retrospective Study

Disc herniation have shown confirmed biomechanical influence on close neighboring vertebrae but the impact on distant neighboring vertebrae remains unknown. After matching age and gender at a single site, we retrospectively evaluated 516 patients with lumbar disc herniation(LDH group)and an equal number of healthy people༈Control group༉to determine the effect of disc herniation on vertebral axial rotation (VAR) in lumbar spine, and explore potential risk factors for VAR in patients with (LDH). Each lumbar spine vertebra's degree of axial rotation was evaluated using the Nash-Moe index. The prevalence of VAR of lumbar spine is greater in LDH group than in Control group (65.7% vs 46.7%, P༜0.001). L2 vertebra in LDH group had the highest frequency of VAR (49.5%), followed by L1(45.1%), and from L3 to L5༈33.6%,8.9%,3.1%༉. The Control group also displayed a similar pattern (L2,39.8%; L1,34.6%; L3,23.2%; L4,3.1%; L5,0.8%). Disc herniation was associated with a higher incidence of VAR in both close and distant neighboring vertebrae. Multivariate analysis showed that age is an independent risk factor for VAR, (OR = 1.245, 95% CI [1.111,1.394], P༜0.001), while symptoms duration and back pain not.