Murase K, Crowninshield R D, Pedersen D R, Chang T S
J Biomech. 1983;16(1):13-22. doi: 10.1016/0021-9290(83)90042-8.
An axisymmetric finite element model of the proximal tibia and cemented tibial component subject to nonaxisymmetric loading is presented. Model variations included polyethylene components and steel reinforced polyethylene components both with and without a central fixation post. Central fixation posts of 35 and 70 mm were modeled. A vertically oriented load applied unilaterally to the tibial component was found to generally cause the largest magnitude peak stresses within the various components of the structure. The addition of steel reinforcement to tibial components without central fixation post is predicted to significantly reduce stress levels within the polymethylmethacrylate and underlying cancellous bone. Although to a lesser extent, the addition of a relatively short central fixation post to the steel reinforced tibial component further reduced these stress levels. The longer steel central fixation post can appreciably reduce proximal cement and bone stress levels. The tibial component condylar width is predicted to have little effect on polymethylmethacrylate and cancellous bone stresses, with the exception that proximal tibial cancellous bone compressive stresses are reduced with wide steel reinforced components.
本文提出了一个受非轴对称载荷作用的胫骨近端和骨水泥固定胫骨部件的轴对称有限元模型。模型变化包括有和没有中央固定柱的聚乙烯部件以及钢增强聚乙烯部件。模拟了35毫米和70毫米的中央固定柱。发现单侧施加于胫骨部件的垂直方向载荷通常会在结构的各个部件中引起最大峰值应力。预计在没有中央固定柱的胫骨部件中添加钢增强材料可显著降低聚甲基丙烯酸甲酯和下方松质骨内的应力水平。虽然程度较小，但在钢增强胫骨部件中添加相对较短的中央固定柱可进一步降低这些应力水平。较长的钢中央固定柱可明显降低近端骨水泥和骨应力水平。预计胫骨部件髁突宽度对聚甲基丙烯酸甲酯和松质骨应力影响不大，不过宽钢增强部件可降低近端胫骨松质骨的压应力。
