Suda E Y, Madeleine P, Hirata R P, Samani A, Kawamura T T, Sacco I C N
Laboratory of Biomechanics of Human Movement, Dept. Physical Therapy, Speech and Occupational Therapy, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil.
SMI, Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Denmark.
Clin Biomech (Bristol). 2017 Feb;42:38-46. doi: 10.1016/j.clinbiomech.2017.01.001. Epub 2017 Jan 4.
This study evaluated the structure and amount of variability of surface electromyography (sEMG) patterns and ankle force data during low-level isometric contractions in diabetic subjects with different degrees of neuropathy.
We assessed 10 control subjects and 38 diabetic patients, classified as absent, mild, moderate, or severe neuropathy, by a fuzzy system based on clinical variables. Multichannel sEMG (64-electrode matrix) of tibialis anterior and gastrocnemius medialis muscles were acquired during isometric contractions at 10%, 20%, and 30% of the maximum voluntary contraction, and force levels during dorsi- and plantarflexion were recorded. Standard deviation and sample entropy of force signals were calculated and root mean square and sample entropy were calculated from sEMG signals. Differences among groups of force and sEMG variables were verified using a multivariate analysis of variance.
Overall, during dorsiflexion contractions, moderate and severe subjects had higher force standard deviation and moderate subjects had lower force sample entropy. During plantarflexion, moderate subjects had higher force standard deviation and all diabetic subjects had lower entropy. Tibialis anterior presented higher root mean square in absent group and lower entropy in mild subjects. For gastrocnemius medialis, entropy was higher in severe and lower in moderate subjects.
Diabetic neuropathy affects the complexity of the neuromuscular system during low-level isometric contractions, reducing the system's capacity to adapt to challenging mechanical demands. The observed patterns of neuromuscular complexity were not associated with disease severity, with the majority of alterations recorded in moderate subject.
本研究评估了不同程度神经病变的糖尿病患者在低水平等长收缩过程中表面肌电图（sEMG）模式和踝关节力量数据的结构及变异性。
我们通过基于临床变量的模糊系统评估了10名对照受试者和38名糖尿病患者，这些糖尿病患者被分类为无神经病变、轻度、中度或重度神经病变。在最大自主收缩的10%、20%和30%进行等长收缩时，采集胫骨前肌和腓肠肌内侧头的多通道sEMG（64电极矩阵），并记录背屈和跖屈过程中的力量水平。计算力量信号的标准差和样本熵，以及sEMG信号的均方根和样本熵。使用多变量方差分析验证力量和sEMG变量组之间的差异。
总体而言，在背屈收缩过程中，中度和重度神经病变受试者的力量标准差较高，中度神经病变受试者的力量样本熵较低。在跖屈过程中，中度神经病变受试者的力量标准差较高，所有糖尿病受试者的熵较低。胫骨前肌在无神经病变组的均方根较高，在轻度神经病变受试者中的熵较低。对于腓肠肌内侧头，重度神经病变受试者的熵较高，中度神经病变受试者的熵较低。
糖尿病神经病变在低水平等长收缩过程中影响神经肌肉系统的复杂性，降低了该系统适应具有挑战性的机械需求的能力。观察到的神经肌肉复杂性模式与疾病严重程度无关，大多数改变记录在中度神经病变受试者中。
