Objective To investigate the effects of two modeling approaches on biomechanical response of finite element models of human tibia. Methods A group of data of a volunteer's CT scan was obtained for 3D reconstruction of tibia, and the solid tibial model with cavity structure was then reconstructed by isolating medullary canal and cancellous bone. Material properties in 2 models were assigned via homogeneous and inhomogeneous modulus, identical load case and boundary conditions were applied to simulate the axial compression and torsion loading on the tibia during the mid-stance phase of gait circle simultaneously. Distribution of stress and displacement, stiffness of axial compression and torsion were compared between two models. Results Regarding to the displacement, two models presented similar distribution on the bone surface. Under the two load cases, inhomogeneous model resulted in lower maximum stress and maximum displacement comparing to homogeneous model. Similarly, inhomogeneous group presented higher axial compression stiffness and torsional stiffness than homogeneous group under the same load case. A physiological stress concentration was observed on the distal part of tibia diaphysis in the homogeneous model, which relatively matched the clinical situation. Conclusions Both of the two modeling patterns could be available for finite element analysis of tibia models. However, homogeneous modeling was associated with higher accuracy for prediction of biomechanical response and flexibility in application compared to inhomogeneous modeling.%目的：探讨两种不同建模方式对胫骨有限元模型生物力学特性的影响。方法采集1例正常志愿者胫骨CT断层扫描数据，对其胫骨模型进行三维重建，分别重建出单纯胫骨外轮廓模型以及带松质骨和髓腔结构的腔体模型，采用相应的灰度公式赋值法和均一赋值法完成模型材料参数赋值，同时对两组设定相同的载荷和边界条件，模拟站立位状态下胫骨上段受到的轴向压缩和扭转载荷，对比两组模型的胫骨应力和位移分布云图、轴向压缩刚度以及扭转刚度。结果两组不同方式构建的胫骨模型总体位移分布基本一致；灰度赋值组的胫骨有限元模型在两种载荷作用下产生的应力峰值和位移幅值均小于均一赋值组，其轴向压缩刚度和扭转刚度均高于均一赋值组；均一赋值组模型在胫骨中下段位置的应力分布相较于灰度赋值组更为集中，相对符合临床实际情况。结论两种建模方式均可满足胫骨有限元分析需求，均一赋值法建模具有更高的准确性，模型应用的灵活性更高。
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