Department of Biomedical Engineering, Faculty of Engineering, The Hong Kong Polytechnic University, Hong Kong, China; Michigan Performance Research Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, USA.
Michigan Performance Research Laboratory, School of Kinesiology, University of Michigan, Ann Arbor, MI, USA.
J Biomech. 2019 May 24;89:65-71. doi: 10.1016/j.jbiomech.2019.04.013. Epub 2019 Apr 13.
Forefoot strike is increasingly being adopted by runners because it can better attenuate impact than rearfoot strike. However, forefoot strike may overload the plantar fascia and alter the plantar fascia elasticity. This study aimed to use ultrasound elastography to investigate and compare shear wave elasticity of the plantar fascia between rearfoot strikers and forefoot strikers. A total of 35 participants (21 rearfoot strikers and 14 forefoot strikers), who were free of lower limb injuries and diseases, were recruited from a local running club. Individual foot strike patterns were identified through the measured plantar pressure during treadmill running. The B-Mode ultrasound images and shear wave elastographic images of the plantar fascia were collected from each runner. Two independent investigators reviewed the images and examined the plantar fascia qualitatively and quantitatively. The results demonstrated an overall good agreement between the investigators in the image review outcomes (ICC:0.96-0.98, κ: 0.89). There were no significant differences in the fascial thickness (p = 0.50) and hypoechogenicity on the gray-scale images (p = 0.54) between the two groups. Shear wave elastography showed that forefoot strikers exhibited reduced plantar fascia elasticity compared to rearfoot strikers (p = 0.01, Cohen's d = 0.91). A less elastic fascial tissue was more easily strained under loading. Tissue overstrain is frequently related to the incidence of plantar fasciitis. While further study is needed for firm conclusions, runners using forefoot strike were encouraged to enhance their foot strength for better protection of the plantar fascia.
前足着地在跑步者中越来越受欢迎，因为它可以比后足着地更好地减轻冲击力。然而，前足着地可能会使足底筋膜过载并改变足底筋膜的弹性。本研究旨在使用超声弹性成像来研究和比较后足着地者和前足着地者足底筋膜的剪切波弹性。共有 35 名参与者（21 名后足着地者和 14 名前足着地者），他们来自当地的一个跑步俱乐部，没有下肢损伤和疾病。通过跑步机跑步时测量的足底压力来确定个体的足着地模式。从每位跑步者采集足底筋膜的 B 型超声图像和剪切波弹性图像。两名独立的研究者对图像进行了审查，并对足底筋膜进行了定性和定量检查。图像审查结果显示，两名研究者之间的总体一致性非常好（ICC：0.96-0.98，κ：0.89）。两组之间筋膜厚度（p=0.50）和灰阶图像的低回声性（p=0.54）均无显著差异。剪切波弹性成像显示，与后足着地者相比，前足着地者的足底筋膜弹性降低（p=0.01，Cohen's d=0.91）。弹性较低的筋膜组织在受力下更容易被拉伸。组织过度拉伸通常与足底筋膜炎的发生率有关。虽然需要进一步的研究来得出确定的结论，但鼓励使用前足着地的跑步者增强脚部力量，以更好地保护足底筋膜。
