Motor adaptation during dorsiflexion-assisted walking with a powered orthosis
Motor adaptation during dorsiflexion-assisted walking with a powered orthosis
复制标题
DOI：
10.1016/j.gaitpost.2008.08.014
复制
发表时间：
2009-02-01
期刊：
影响因子：
2.4
通讯作者：
Ferris, Daniel P.
中科院分区：
文献类型：
--
作者：
Kao, Pei-Chun;Ferris, Daniel P.
提供动力辅助的机器人踝足矫形器（AFO）可以比刚性 AFO 更好地适应不同的步态动态。为了深入了解人类如何适应动力 AFO，我们研究了神经系统完好的受试者使用由胫骨前肌电图 (EMG) 比例控制的主动背屈辅助矫形器行走时的反应。我们通过招募两组健康受试者来检查步态中踝背屈肌的两种机械功能（脚跟着地时的能量吸收和脚趾离地时的发电）：第一组，称为连续控制（n = 5），在脚跟初始接触和摆动期间都有背屈辅助；第二组称为“挥杆控制”（n = 5），仅在挥杆期间提供帮助。我们假设两组受试者通过动力背屈辅助练习行走都会降低胫骨前肌肌电图振幅。十名健康受试者配备了定制的矫形器，其中包括提供背屈肌扭矩的人造气动肌肉。当受试者在跑步机上行走并进行两次 30 分钟的训练时，我们收集了下半身运动学、肌电图和人工肌肉力。我们发现受试者行走时踝关节背屈增加了 9 度，但对两个胫骨前肌 EMG 爆发表现出不同的适应反应。脚跟着地时的第一次 EMG 爆发具有相似的 28% 低幅度 (p < 0.05)，但摆动过程中的第二次 EMG 爆发具有相似的幅度。这些结果提供了肌电图控制背屈辅助神经完整人类的基线数据，可用于指导未来对神经受损个体的研究。 (c) 2008 Elsevier B.V. 保留所有权利。
A robotic ankle-foot orthosis (AFO) that provides powered assistance could adjust to varying gait dynamics much better than a rigid AFO. To provide insight into how humans would adapt to a powered AFO, we studied the response of neurologically intact subjects walking with an active dorsiflexion assist orthosis proportionally controlled by tibialis anterior electromyography (EMG). We examined the two mechanical functions of ankle dorsiflexors in gait (power absorption at heel strike and power generation at toe-off) by recruiting two groups of healthy subjects: Group One, called Continuous Control (n = 5), had dorsiflexion assistance both at the initial heel contact and during swing; Group Two, called Swing Control (n = 5), had the assistance only during swing. We hypothesized both groups of subjects would reduce tibialis anterior EMG amplitude with practice walking with the powered dorsiflexion assist. Ten healthy subjects were fitted with custom-made orthoses that included an artificial pneumatic muscle providing dorsiflexor torque. We collected lower body kinematics, EMG, and artificial muscle force while subjects walked on a treadmill for two 30-min training sessions. We found that subjects walked with increased ankle dorsiflexion by 9 degrees but showed different adaptation responses of the two tibialis anterior EMG bursts. The first EMG burst around heel strike had similar to 28% lower amplitudes (p < 0.05) but the second EMG burst during swing had similar amplitudes. These results provide baseline data of EMG controlled dorsiflexion assist in neurologically intact humans that can be used to guide future studies on neurologically impaired individuals. (c) 2008 Elsevier B.V. All rights reserved.