National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, PR China.
National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, PR China; Science Lab, Zhejiang Red Dragonfly Footwear Co., LTD., Zhejiang Province, Wenzhou 325100, PR China.
Gait Posture. 2020 Jan;75:1-7. doi: 10.1016/j.gaitpost.2019.09.013. Epub 2019 Sep 24.
Coordination is the ability to assemble and maintain appropriate relations between joints. Investigating limb coordination in curve-turning (CT) walking could provide insightful information about the coordinating strategies and neuro-musculoskeletal system (NMSS) control in human motion.
Although preschoolers have already established an adult-like gait, how preschoolers perform their specific gait pattern when walking in CT and what coordination strategies they would choose during the turning process have not yet been systematically considered. Therefore, this study was aimed to investigate preschoolers' coordination mechanism during asymmetric motion, in order to understand the development of their NMSS control in locomotion.
Kinematics data in the lower and upper limbs of 45 healthy preschoolers walking with the curve-turning task was measured by the Coda Motion System. The Continuous Relative Phase (CRP) angle and the variability between the knee and ankle, hip and knee, as well as the thorax-humerus joint (THJ) and elbow were calculated.
The outcome demonstrates that as the curve angles increased, the stride length and Froude number of preschoolers significantly decreased (p < 0.05 for all); meanwhile, a more out of phase coordination pattern in CRP and an increase in VCRP values were found. Group analysis showed that the significant differences in CRP and VCRP between preschoolers and adults increased with curve angles in all coupled joints - the highest in that of the Knee-Ankle coupling, followed by those of the Hip-Knee and THJ-Elbow.
Our results suggest that to achieve curve-turning, preschoolers first chose to modify their STP, then to adjust coordination for coupling-joints in the Knee-Ankle, Hip-Knee, and THJ-Elbow systems. Additionally, preschoolers are still in a gait fine-tuning period and their NMSS control of motion is not as precise as that of adults.
协调是指在关节之间组装和维持适当关系的能力。研究曲线转弯（CT）行走中的肢体协调，可以为人类运动的协调策略和神经肌肉骨骼系统（NMSS）控制提供有见地的信息。
尽管学龄前儿童已经建立了成人般的步态，但当他们在 CT 中行走时，他们如何表现出特定的步态模式，以及在转弯过程中他们会选择哪些协调策略，这些问题尚未得到系统考虑。因此，本研究旨在调查学龄前儿童在不对称运动中的协调机制，以了解他们在运动中 NMSS 控制的发展。
通过 Coda 运动系统测量 45 名健康学龄前儿童在进行曲线转弯任务时的下肢和上肢运动学数据。计算连续相对相位（CRP）角度和膝关节与踝关节、髋关节与膝关节以及胸-肱骨关节（THJ）和肘之间的变异性。
结果表明，随着曲线角度的增加，学龄前儿童的步长和弗鲁德数显著减小（p<0.05）；同时，CRP 中出现了更为不同步的协调模式，并且 VCRP 值增加。组间分析表明，在所有耦合关节中，CRP 和 VCRP 在学龄前儿童和成年人之间的差异随着曲线角度的增加而显著增加-在膝关节和踝关节耦合中最大，其次是髋关节和膝关节以及 THJ-肘部。
我们的结果表明，为了实现曲线转弯，学龄前儿童首先选择修改他们的步长，然后调整膝关节、髋关节和 THJ-肘部系统中耦合关节的协调。此外，学龄前儿童仍处于步态微调阶段，他们的 NMSS 运动控制不如成年人精确。
