Influence of simulated neuromuscular noise on movement variability and fall risk in a 3D dynamic walking model.
Influence of simulated neuromuscular noise on movement variability and fall risk in a 3D dynamic walking model.
复制标题
模拟神经肌肉噪声对 3D 动态步行模型中运动变异性和跌倒风险的影响。
DOI：
10.1016/j.jbiomech.2010.07.008
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发表时间：
2010
影响因子：
2.4
通讯作者：
Dingwell,JonathanB
中科院分区：
文献类型：
--
作者：
Roos,PaulienE;Dingwell,JonathanB
有跌倒风险的人表现出更大的步态变异性，这可能预示着未来的跌倒。然而，这些相关性背后的因果机制尚不清楚。与衰老相关的神经元噪音增加可能导致步态变异性增加，进而导致跌倒风险增加。本文提出了一个神经肌肉噪声变化如何独立影响步态变异性和跌倒概率的模型，旨在确定步态变异性变化直接预测跌倒风险的程度。我们使用了一个动态步行模型，该模型包含一个横向台阶控制器来保持横向稳定性。噪声被应用于该控制器以近似人类的神经肌肉噪声。噪声幅值在低幅值和高幅值之间变化，低幅值不会导致模型下降。随着噪声幅值的增加，模型下降的次数增加，步长减少。步态变异性随着噪声幅度的增加而增加，预示着跌倒的可能性增加。重要的是，这些关系不是线性的。无论是低步态变异性还是高步态变异性，噪音和变异性的小幅增加对跌倒概率的影响都很小。相反，在中等噪声和/或可变性水平下，同样的小幅度增加导致下降概率的大幅增加。我们的研究结果证实了这样一种观点，即与年龄相关的神经肌肉噪音的增加可能直接导致跌倒风险的增加。然而，神经肌肉噪声仍然只是许多需要考虑的重要因素之一。这些发现对预防跌倒的研究和实践具有重要意义。
People at risk of falling exhibit increased gait variability, which may predict future falls. However, the causal mechanisms underlying these correlations are not well known. Increased neuronal noise associated with aging likely leads to increased gait variability, which could in turn lead to increased fall risk. This paper presents a model of how changes in neuromuscular noise independently affect gait variability and probability of falling, and aims to determine the extent to which changes in gait variability directly predict fall risk. We used a dynamic walking model that incorporates a lateral step controller to maintain lateral stability. Noise was applied to this controller to approximate neuromuscular noise in humans. Noise amplitude was varied between low amplitudes that did not induce falls and high amplitudes for which the model always fell. With increases in noise amplitude, the model fell more often and after fewer steps. Gait variability increased with noise amplitude and predicted increased probability of falling. Importantly, these relationships were not linear. At either low gait variability or very high gait variability, small increases in noise and variability affected probability of falling very little. Conversely, at intermediate noise and/or variability levels, the same small increases resulted in large increases in probability of falling. Our results validate the idea that age-related increases in neuromuscular noise likely play a direct contributing role in increasing fall risk. However, neuromuscular noise remains only one of many important factors that need to be considered. These findings have important implications for fall prevention research and practice.