Analysis of linear electrode array EMG for assessment of hemiparetic biceps brachii muscles.
Analysis of linear electrode array EMG for assessment of hemiparetic biceps brachii muscles.
复制标题
线性电极阵列肌电图分析用于评估偏瘫肱二头肌
DOI：
10.3389/fnhum.2015.00569
复制
发表时间：
2015
影响因子：
2.9
通讯作者：
Zhou P
中科院分区：
文献类型：
--
作者：
Yao B;Zhang X;Li S;Li X;Chen X;Klein CS;Zhou P
本研究对14例偏瘫中风患者的双侧肱二头肌线性电极阵列获得的肌表面电图（EMG）信号进行了频率分析。对于最大自主收缩（MVC）的10%至80%不等的不同程度的等距收缩，我们检查了沿肌纤维近端至远端排列的19个双极表面肌电通道的功率谱。研究发现，在所有中风受试者中，从不同表面肌电通道平均得到的中位频率（MF）和平均工频（MPF），在每个匹配的MVC收缩百分比中，与对侧肌肉相比，paretic肌的中位频率（MF）和平均工频（MPF）明显更小。轻瘫肌的肌纤维传导速度（MFCV）明显低于对侧肌。在双亲和对侧肌肉中，平均MF、MPF或MFCV与扭矩之间没有明显的相关性。然而，全球MFCV与MF之间存在显著的正相关。对单个肌电通道的检查显示，离估计的肌肉神经支配区最近的电极产生的表面肌电信号的MF和MPF明显高于双亲侧和对侧近端或远端位置。这些发现表明，复杂的中枢和周围神经肌肉改变（如大运动单元的选择性丧失、运动单元的控制紊乱、运动单元同步增加和肌纤维萎缩等）可以共同影响表面肌电信号。神经支配区的频率差异也证实了表面肌电分析中电极位置的相关性。
This study presents a frequency analysis of surface electromyogram (EMG) signals acquired by a linear electrode array from the biceps brachii muscles bilaterally in 14 hemiparetic stroke subjects. For different levels of isometric contraction ranging from 10 to 80% of the maximum voluntary contraction (MVC), the power spectra of 19 bipolar surface EMG channels arranged proximally to distally along the muscle fibers were examined in both paretic and contralateral muscles. It was found that across all stroke subjects, the median frequency (MF) and the mean power frequency (MPF), averaged from different surface EMG channels, were significantly smaller in the paretic muscle compared to the contralateral muscle at each of the matched percent MVC contractions. The muscle fiber conduction velocity (MFCV) was significantly slower in the paretic muscle than in the contralateral muscle. No significant correlation between the averaged MF, MPF, or MFCV vs. torque was found in both paretic and contralateral muscles. However, there was a significant positive correlation between the global MFCV and MF. Examination of individual EMG channels showed that electrodes closest to the estimated muscle innervation zones produced surface EMG signals with significantly higher MF and MPF than more proximal or distal locations in both paretic and contralateral sides. These findings suggest complex central and peripheral neuromuscular alterations (such as selective loss of large motor units, disordered control of motor units, increased motor unit synchronization, and atrophy of muscle fibers, etc.) which can collectively influence the surface EMG signals. The frequency difference with regard to the innervation zone also confirms the relevance of electrode position in surface EMG analysis.