Trinity Centre for Biomedical Engineering, Trinity College Dublin, Dublin, Ireland; Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland; School of Medicine, Trinity College Dublin, Dublin, Ireland.
Trinity Centre for Biomedical Engineering, Trinity College Dublin, Dublin, Ireland; Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland; School of Engineering, Trinity College Dublin, Dublin, Ireland.
Gait Posture. 2023 Sep;105:125-131. doi: 10.1016/j.gaitpost.2023.07.283. Epub 2023 Aug 1.
The Sit-to-Stand (STS) transition is one of the most used activities of daily living and vital for independence. Neurological, or physical injuries impairing functional mobility or sensory feedback often require rehabilitative programs or therapeutic interventions. Understanding the biomechanical elements of daily movements and the interaction between these elements may help inform rehabilitation protocols and optimize targeted interventions, such as stimulation protocols.
What are the effects of different initial knee angle, arm facilitation and proprioceptive input on leg muscle activation patterns and balance during and after a sit-to-stand?
EMG of four lower limb muscles were recorded in 20 healthy participants as well centre-of-pressure sway amplitude and velocity, as participants stood from a seated position. Initial knee angles were set to various levels of extension (80°, 90°, 100°) and surface stability and arm facilitation were altered using a foam mat or crossing arms. Data were analysed across 3 phases of the STS transition.
More extended knee angles resulted in greater mediolateral sway during each phase (p < .01) and had a detrimental effect on anterior-posterior sway in phases 1 and 3. EMG data suggested more extended initial knee angles also increased EMG activity of the Tibialis Anterior (p < .001) and Bicep Femoris (p < .02) within Phases 1 and 2 to assist lift and stabilisation.
Findings of this study outline phase-based muscle involvement as well as the compounding effects of reduced proprioceptive input and knee angle, on difficulty of the STS transition. Such results emphasising the need to take sensory and mobility issues into consideration when designing rehabilitative programs or stimulation control systems.
坐站（STS）转换是最常用的日常生活活动之一，对独立性至关重要。神经或身体损伤会损害功能移动性或感觉反馈，通常需要康复计划或治疗干预。了解日常运动的生物力学元素以及这些元素之间的相互作用，可以帮助确定康复方案，并优化有针对性的干预措施，例如刺激方案。
不同初始膝关节角度、手臂辅助和本体感觉输入对坐姿到站姿过程中和之后腿部肌肉激活模式和平衡的影响。
在 20 名健康参与者中记录了四个下肢肌肉的肌电图，以及在参与者从坐姿站立时的中心压力摆动幅度和速度。初始膝关节角度设定为不同的伸展水平（80°、90°、100°），并使用泡沫垫或交叉手臂改变表面稳定性和手臂辅助。数据在 STS 转换的三个阶段进行分析。
更伸展的膝关节角度导致每个阶段的横向摆动更大（p<.01），并且对第 1 阶段和第 3 阶段的前后摆动产生不利影响。肌电图数据表明，更伸展的初始膝关节角度也增加了胫骨前肌（p<.001）和二头肌股骨（p<.02）在第 1 阶段和第 2 阶段的肌电图活动，以协助提升和稳定。
本研究的结果概述了基于阶段的肌肉参与，以及感觉输入和膝关节角度降低对 STS 转换难度的综合影响。这些结果强调了在设计康复计划或刺激控制系统时需要考虑感觉和移动性问题。
