Watanabe Kunihiro, Mutsuzaki Hirotaka, Fukaya Takashi, Aoyama Toshiyuki, Nakajima Syuichi, Sekine Norio, Mori Koichi
Department of Radiology, Shin-Oyama City Hospital, Oyama-shi 323-0827, Tochigi, Japan.
Center for Medical Sciences, Faculty of Health Sciences, Ibaraki Prefectural University of Health Sciences, Ami 300-0394, Ibaraki, Japan.
J Funct Morphol Kinesiol. 2023 Jan 27;8(1):15. doi: 10.3390/jfmk8010015.
This study aimed to evaluate the mechanism of progression involved in knee osteoarthritis (OA). We used the computed tomography-based finite element method (CT-FEM) of quantitative X-ray CT imaging to calculate and create a model of the load response phase, wherein the greatest burden is placed on the knee joint while walking. Weight gain was simulated by asking a male individual with a normal gait to carry sandbags on both shoulders. We developed a CT-FEM model that incorporated walking characteristics of individuals. Upon simulating changes owing to a weight gain of approximately 20%, the equivalent stress increased extensively in both medial and lower leg aspects of the femur and increased medio-posteriorly by approximately 230%. As the varus angle increased, stress on the surface of the femoral cartilage did not change significantly. However, the equivalent stress on the surface of the subchondral femur was distributed over a wider area, increasing by approximately 170% in the medio-posterior direction. The range of equivalent stress affecting the lower-leg end of the knee joint widened, and stress on the posterior medial side also increased significantly. It was reconfirmed that weight gain and varus enhancement increase knee-joint stress and cause the progression of OA.
本研究旨在评估膝关节骨关节炎（OA）进展的机制。我们采用基于计算机断层扫描的定量X射线CT成像有限元方法（CT-FEM）来计算并创建负荷反应阶段的模型，在此阶段行走时膝关节承受的负担最大。通过让一名步态正常的男性个体双肩背负沙袋来模拟体重增加。我们开发了一个纳入个体行走特征的CT-FEM模型。在模拟体重增加约20%后的变化时，股骨内侧和小腿部位的等效应力大幅增加，在中后方向增加了约两倍半。随着内翻角度增加，股骨软骨表面的应力没有显著变化。然而，股骨软骨下表面的等效应力分布范围更广区域，在中后方向增加了约170%。影响膝关节小腿端的等效应力范围变宽，后内侧的应力也显著增加。再次证实体重增加和内翻加重会增加膝关节应力并导致OA进展。
