微创椎间隙注入骨水泥对上下椎体应力的影响

Effect of minimally invasive intervertebral space bone cement injection on upper and lower vertebral body stress

摘要:

目的 通过建立腰椎模型进行生物力学分析，研究椎间盘中注入骨水泥后对上下椎体所受最大应力的影响，降低后期患者在运动和劳动中椎体骨折的风险，为治疗腰椎疼痛及椎间隙注入骨水泥手术提供实验数据和参考。方法 获取符合要求的CT数据，利用Mimics、Geomagic Wrap、SolidWorks、Ansys Workbench等软件构建实验要求的腰椎有限元模型，将构建的模型进行前屈、后伸、左弯、右弯、左旋、右旋、站立运动状态分析，比较注入在不同位置和注入不同量的骨水泥对上下椎体的应力影响和变化趋势。结果 成功建立了腰椎三维有限元模型。构建的腰椎三维有限元模型在各种运动中分析的结果均在既往文献数据参考范围内，可认为模型有效，可以进行下一步的实验研究。通过分析研究发现骨水泥注入到椎间盘的左侧、中间、右侧三者之间对椎体表面的最大应力差异无统计学意义（P>0.05）。通过在椎间盘中注入1 mL、4 mL和7 mL骨水泥后分析发现随着骨水泥注入量的增加上下椎体表面所受的最大应力明显下降，差异有统计学意义（P<0.05）。结论 考虑到人体的实际运动更加多样和复杂等综合因素骨水泥注入到椎间盘中间更加合理，综合过往的文献和本次的实验研究在椎间盘中注入4~7 mL（50%~100%）骨水泥能达到良好的效果，但是不建议注入到100%，骨水泥渗漏的风险过大，可为临床治疗提高参考。

Abstract:

Objective Through the establishment of a lumbar spine model for biomechanical analysis, the influence of bone cement injection in the intervertebral disc on the maximum stress of the upper and lower vertebrae was studied, so reduce the risk of vertebral fractures during exercise and labor in later patients, and provide experimental data and reference for the treatment of lumbar pain and the operation of bone cement injection in the intervertebral space.Methods The required CT data was obtained, Mimics, Geomagic Wrap, SolidWorks, Ansys Workbench and other software were used to construct the finite element model of the lumbar spine required by the experiment, and the constructed model's forward bending, backward extension, left bending, right bending, left rotation, right rotation, and standing motion state were analyzed. The influence and change trend of the stress of upper and lower vertebrae with different amount of bone cement injected at different positions were compared.Results The three-dimensional finite element model of lumbar spine was successfully established. The results of analyzing the constructed three-dimensional finite element model of the lumbar spine in various movements were within the reference range of the previous literature data, and the model can be considered valid for the next experimental study. Through analysis and study, it was found that bone cement injected into the left, middle and right sides of the intervertebral disc had no significant difference in the maximum stress on the vertebral surface (P>0.05). Moreover, the maximum stress on the upper and lower vertebral surfaces decreased significantly with the increase of the injection amount of bone cement after 1 mL, 4 mL and 7 mL of bone cement were injected into the intervertebral disc,and there were significant differences (P<0.05).Conclusion Considering the fact that the actual movement of the human body is more diverse and complex and other comprehensive factors, it is more reasonable to inject bone cement into the intervertebral disc. Based on the previous literature and this experimental study, injecting 4 mL to 7 mL (50% to 100%) bone cement into the intervertebral disc can achieve a good effect, but it is not recommended to inject 100%, because the risk of bone cement leakage is too large, it can provide reference for clinical treatment.