Su Wanyan, Zhang Shen, Ye Dongqiang, Sun Xiaole, Zhang Xini, Fu Weijie
School of Kinesiology, Shanghai University of Sport, Shanghai, China.
School of Physical Education and Training, Shanghai University of Sport, Shanghai, China.
Front Bioeng Biotechnol. 2022 Jun 28;10:917675. doi: 10.3389/fbioe.2022.917675. eCollection 2022.
Shoes affect the biomechanical properties of the medial longitudinal arch (MLA) and further influence the foot's overall function. Most previous studies on the MLA were based on traditional skin-marker motion capture, and the observation of real foot motion inside the shoes is difficult. Thus, the effect of shoe parameters on the natural MLA movement during running remains in question. Therefore, this study aimed to investigate the differences in the MLA's kinematics between shod and barefoot running by using a high-speed dual fluoroscopic imaging system (DFIS). Fifteen healthy habitual rearfoot runners were recruited. All participants ran at a speed of 3 m/s ± 5% along with an elevated runway in barefoot and shod conditions. High-speed DFIS was used to acquire the radiographic images of MLA movements in the whole stance phase, and the kinematics of the MLA were calculated. Paired sample t-tests were used to compare the kinematic characteristics of the MLA during the stance phase between shod and barefoot conditions. Compared with barefoot, shoe-wearing showed significant changes ( < 0.05) as follows: 1) the first metatarsal moved with less lateral direction at 80%, less anterior translation at 20%, and less superiority at 10-70% of the stance phase; 2) the first metatarsal moved with less inversion amounting to 20-60%, less dorsiflexion at 0-10% of the stance phase; 3) the inversion/eversion range of motion (ROM) of the first metatarsal relative to calcaneus was reduced; 4) the MLA angles at 0-70% of the stance phase were reduced; 5) the maximum MLA angle and MLA angle ROM were reduced in the shod condition. Based on high-speed DFIS, the above results indicated that shoe-wearing limited the movement of MLA, especially reducing the MLA angles, suggesting that shoes restricted the compression and recoil of the MLA, which further affected the spring-like function of the MLA.
鞋子会影响内侧纵弓（MLA）的生物力学特性，并进而影响足部的整体功能。以往大多数关于MLA的研究都基于传统的皮肤标记物运动捕捉，而观察鞋子内部真实的足部运动较为困难。因此，鞋类参数对跑步过程中自然MLA运动的影响仍不明确。所以，本研究旨在通过使用高速双荧光透视成像系统（DFIS）来探究穿鞋跑步和赤足跑步时MLA的运动学差异。招募了15名习惯后足着地的健康跑步者。所有参与者在赤足和穿鞋条件下，沿着一条升高的跑道以3 m/s±5%的速度跑步。使用高速DFIS获取整个站立阶段MLA运动的X射线图像，并计算MLA的运动学参数。采用配对样本t检验比较赤足和穿鞋条件下站立阶段MLA的运动学特征。与赤足相比，穿鞋时出现了如下显著变化（<0.05）：1）在站立阶段的80%时，第一跖骨向外侧移动较少，在20%时向前平移较少，在10%-70%时向上移动较少；2）第一跖骨内翻减少20%-60%，在站立阶段的0%-10%时背屈减少；3）第一跖骨相对于跟骨的内翻/外翻活动范围（ROM）减小；4）在站立阶段的0%-70%时MLA角度减小；5）在穿鞋条件下，MLA最大角度和MLA角度ROM减小。基于高速DFIS，上述结果表明穿鞋限制了MLA的运动，尤其是减小了MLA角度，这表明鞋子限制了MLA的压缩和回弹，进而影响了MLA的弹簧样功能。
