Zhu Xiaolan, Liu Jiaojiao, Liu Hui, Liu Jingxi, Yang Yufeng, Wang Haichun
Sport Science School, Beijing Sport University, Beijing 100084, China.
School of Naval Architecture and Ocean Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
Bioengineering (Basel). 2023 Apr 27;10(5):533. doi: 10.3390/bioengineering10050533.
High long-term stress on the plantar fascia (PF) is the main cause of plantar fasciitis. Changes in the midsole hardness (MH) of running shoes are an important factor leading to the alteration of the PF. This study aims to establish a finite-element (FE) model of the foot-shoe, and investigates the effects of midsole hardness on PF stress and strain. The FE foot-shoe model was built in ANSYS using computed-tomography imaging data. Static structural analysis was used to simulate the moment of running push and stretch. Plantar stress and strain under different MH levels were quantitatively analyzed. A complete and valid 3D FE model was established. With an increase in MH from 10 to 50 Shore A, the overall stress and strain of the PF were decreased by approximately 1.62%, and the metatarsophalangeal (MTP) joint flexion angle was decreased by approximately 26.2%. The height of the arch descent decreased by approximately 24.7%, but the peak pressure of the outsole increased by approximately 26.6%. The established model in this study was effective. For running shoes, increasing the MH reduces the stress and strain of PF, but also imposes a higher load on the foot.
足底筋膜（PF）长期承受的高应力是足底筋膜炎的主要原因。跑鞋中底硬度（MH）的变化是导致PF改变的一个重要因素。本研究旨在建立足-鞋的有限元（FE）模型，并研究中底硬度对PF应力和应变的影响。利用计算机断层扫描成像数据在ANSYS中构建了FE足-鞋模型。采用静态结构分析来模拟跑步蹬地和伸展瞬间。定量分析了不同MH水平下的足底应力和应变。建立了一个完整且有效的三维FE模型。随着MH从10邵氏A增加到50邵氏A，PF的整体应力和应变降低了约1.62%，跖趾（MTP）关节屈曲角度降低了约26.2%。足弓下降高度降低了约24.7%，但外底峰值压力增加了约26.6%。本研究建立的模型是有效的。对于跑鞋来说，增加MH可降低PF的应力和应变，但也会给足部带来更高的负荷。
