创伤事件可能导致腰椎损伤,从低严重程度的骨性骨折到复杂的骨折脱位。损伤机理以及加载速率和韧带机械性能的影响尚未完全阐明。目的是量化在创伤性屈曲剪切条件下冲击速度和韧带特性变异性对腰椎反应的影响。L1-L3有限元脊柱节段以三种速度(2.7、5或10m/s)和27组韧带特性经受前后撞击。脊柱损伤的病理机制根据撞击速度而变化:对于低速和中等速度,前柱的初始骨压缩与对于高速,后柱的牵引。2.7和5m/s的冲击会导致更高的骨损伤程度,即,骨破裂的体积,与10m/s(分别为1140、1094和718mm3)时的冲击相比,下L2前移(分别为2.09、5.36和7.72mm),下小关节骨折的发生。韧带特性对骨损伤的发生没有影响,但影响了小关节骨折的存在。这些结果提高了对腰椎损伤病理机制的理解,并提供了可用于预防损伤的腰椎损伤负荷阈值的额外知识。图形抽象在损伤开始和最终损伤模式识别时,腰椎段遭受创伤性前后撞击的应力分布分析。
Traumatic events may lead to lumbar spine injuries ranging from low severity bony fracture to complex fracture dislocation. Injury pathomechanisms as well as the influence of loading rate and ligament mechanical properties were not yet fully elucidated. The objective was to quantify the influence of impact velocity and ligament properties variability on the lumbar spine response in traumatic flexion-shear conditions. An L1-L3 finite element spinal segment was submitted to a posterior-anterior impact at three velocities (2.7, 5, or 10 m/s) and for 27 sets of ligament properties. Spinal injury
pathomechanism varied according to the impact velocities: initial osseous compression in the anterior column for low and medium velocities versus distraction in the posterior column for high velocity. Impact at 2.7 and 5 m/s lead to higher extent of bony injury, i.e., volume of ruptured bone, compared to the impact at 10 m/s (1140, 1094, and 718 mm3 respectively), lower L2 anterior displacement (2.09, 5.36, and 7.72 mm respectively), and lower facet fracture occurrence. Ligament properties had no effect on bony injury initiation but influenced the presence of facet fracture. These results improve the understanding of lumbar injury pathomechanisms and provide additional knowledge of lumbar injury load thresholds that could be used for injury prevention. Graphical abstract Stress distribution analysis at the injury initiation and final injury pattern identification for a lumbar segment submitted to a traumatic posterior-anterior impact.