Watanabe Kunihiro, Mutsuzaki Hirotaka, Fukaya Takashi, Aoyama Toshiyuki, Nakajima Syuichi, Sekine Norio, Mori Koichi
Department of Radiology, Saitama Prefecture Saiseikai Kurihashi Hospital, Kuki, Saitama 349-1105, Japan.
Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Arakawa, Tokyo 116-8551, Japan.
Medicina (Kaunas). 2020 Jan 29;56(2):56. doi: 10.3390/medicina56020056.
There are no reports on articular stress distribution during walking based on any computed tomography (CT)-finite element model (CT-FEM). This study aimed to develop a calculation model of the load response (LR) phase, the most burdensome phase on the knee, during walking using the finite element method of quantitative CT images. The right knee of a 43-year-old man who had no history of osteoarthritis or surgeries of the knee was examined. An image of the knee was obtained using CT and the extension position image was converted to the flexion angle image in the LR phase. The bone was composed of heterogeneous materials. The ligaments were made of truss elements; therefore, they do not generate strain during expansion or contraction and do not affect the reaction force or pressure. The construction of the knee joint included material properties of the ligament, cartilage, and meniscus. The extensor and flexor muscles were calculated and set as the muscle exercise tension around the knee joint. Ground reaction force was vertically applied to suppress the rotation of the knee, and the thigh was restrained. An FEM was constructed using a motion analyzer, floor reaction force meter, and muscle tractive force calculation. In a normal knee, the equivalent stress and joint contact reaction force in the LR phase were distributed over a wide area on the inner upper surface of the femur and tibia. We developed a calculation model in the LR phase of the knee joint during walking using a CT-FEM. Methods to evaluate the heteromorphic risk, mechanisms of transformation, prevention of knee osteoarthritis, and treatment may be developed using this model.
目前尚无基于任何计算机断层扫描（CT）有限元模型（CT - FEM）的关于行走过程中关节应力分布的报告。本研究旨在使用定量CT图像的有限元方法，建立一个关于行走过程中膝关节负担最重阶段——负荷反应（LR）阶段的计算模型。对一名43岁无骨关节炎病史且无膝关节手术史的男性的右膝进行了检查。使用CT获取膝关节图像，并将伸展位图像转换为LR阶段的屈曲角度图像。骨骼由异质材料组成。韧带由桁架单元构成；因此，它们在伸展或收缩过程中不会产生应变，也不会影响反作用力或压力。膝关节的构建包括韧带、软骨和半月板的材料特性。计算并设定伸肌和屈肌为膝关节周围的肌肉运动张力。垂直施加地面反作用力以抑制膝关节的旋转，并对大腿进行约束。使用运动分析仪、地面反作用力计和肌肉牵引力计算构建有限元模型。在正常膝关节中，LR阶段的等效应力和关节接触反作用力分布在股骨和胫骨内上表面的广泛区域。我们使用CT - FEM建立了行走过程中膝关节LR阶段的计算模型。利用该模型可能会开发出评估异形风险、转化机制、预防膝关节骨关节炎及治疗的方法。
