在跨肢截肢后,残余肌肉中发生了变化的运动单元特性
Noah Rubin1, Robert Hinson2,1,3, Katherine Saul4
1UNC/NC State Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States of America.
Journal of neural engineering
|January 4, 2024
概括
截肢改变了残余肌肉中的神经信号,影响了对假肢控制至关重要的运动单元特性. 为了改进肌电假肢,需要重新评估运动单元招募和放电的模型.
科学领域:
- 神经科学是一个神经科学.
- 生物医学工程 生物医学工程
- 康复科学 康复科学 康复科学
背景情况:
- 动力假肢依赖于从残余肢体肌肉中解码神经信号.
- 当前的肌电控制器假设剩余的肌肉活动反映完整的肌肉.
- 肢体截肢可能会改变运动单元 (MU) 的特性,影响假肢控制的准确性.
研究的目的:
- 为了研究穿骨截肢后残余肌肉中运动单元 (MU) 属性的变化.
- 为了比较完整和残余肌肉之间的MU招募,动作潜能幅度和发射率.
- 了解这些变化如何影响既定原则,如亨纳曼的大小原则和洋皮现象.
主要方法:
- 从6名截肢者的残留和完整的前肌 (TA) 和腹肌 (GA) 肌肉中记录的表面电肌图 (EMG).
- EMG分解为MU尖列车,以分析招聘门,MU大小和射击率.
- 分析相关性以模拟亨纳曼的大小原理和速率-大小关联,比较完整与残留肌肉.
主要成果:
- 剩余TA显示大小原理和洋皮现象的相关性明显较低,斜率较平.
- 在大多数受试者中,残留GA在很大程度上不受影响;之前的肌电训练对TA斜率的影响最小.
- 速度与大小的关联关系被保留了,但这两个残余肌肉都表现出更平坦的放电率衰减.
结论:
- 截肢造成的外周神经肌肉损伤会导致脊柱水平的功能重组.
- 目前用于残留肌肉EMG生成的模型需要重新参数化,以考虑观察到的MU属性干扰.
- 追踪MU池适应可以作为神经肌肉控制的生物标志物,帮助肌电假肢训练.
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