Evaluation of Mechanical Robustness of Bone by an Individual Modeling Method

本研究的目的是开发一种新的系统来评估具有完整状态的椎体的机械稳健性。为了实现该系统，本课题采用计算方法对椎体的生物力学特性进行了研究。首先，使用pQCT对大鼠椎体进行断层成像。然后，使用作者开发的自动建模方法生成椎体的三维有限元模型。通过x线CT数计算各单元骨强度和杨氏模量。其次，使用同一椎体骨进行椎体压缩试验。在压缩加载条件下进行了应力分析。最后，计算应力比η=σ/σ _b来评价骨的力学稳健性。断口部分与计算结果中大η的断口部分吻合较好。

The purpose of this research is to develop a new system to evaluate mechanical robustness of a vertebral body with intact states. To realize the system, this research project investigated biomechanical properties of vertebral body with a computational method. First, sectional images of a rat's vertebral body were taken using pQCT. Then, a three-dimensional finite element model of the vertebra was generated by an automated modeling method developed by authors. Strength of bone and Young's modulus for the each element were calculated by the X-ray CT number. Second, a compression test using the vertebral body was performed with the same vertebral bone. Stress analysis was executed under the compressive loading conditions. Finally, a stress ratio η=σ/σ_B was calculated to evaluate the mechanical robustness of the bone. The portion of the fracture was well in accord with that of large η in the computational result.