The National Clinical Research Center for Geriatrics, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China.
Medical Equipment Innovation Research Center, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China.
Biomed Eng Online. 2024 Nov 18;23(1):115. doi: 10.1186/s12938-024-01310-3.
Sarcopenia is an age-related, insidious, crippling but curable degenerative disease if diagnosed and treated early. However, no accessible and accurate early screening method is available for community settings that does not require specialized personnel. One of the hallmarks of sarcopenia is the pathological changes of muscle fiber type composition and motor unit firing patterns. Surface electromyography (sEMG) may serve as an effective tool for detecting differences between healthy and sarcopenic individuals due to its superior wearability and accessibility compared to other screening methods such as medical imaging and bioimpedance measurements, making it ideal for community-based sarcopenic screening. Our study aims to explore sEMG biomarkers that can be used for screening or diagnosis of sarcopenia.
We collected multi-channel sEMG signals from six forearm muscles of 98 healthy and 55 sarcopenic community-dwelling older adults. Participants performed grasp tasks at 20% and 50% of maximum voluntary contraction (MVC). Hexagons created by various EMG features, normalized with respect to respective MVC, and symmetry analyses were performed to estimate multi-muscle coordination patterns. An innovative index, namely incenter-circumcenter distance of muscle coordination (ICDMC), is proposed to discriminate between the healthy and sarcopenic groups. We utilized non-parametric tests to compare the ICDMC between the two groups, considering a p-value less than 0.05 statistically significant. The results showed that at 20% MVC, ICDMCs from root mean square (RMS), mean absolute value (MAV), slope sign changes (SSC) and wavelength (WL) showed statistically significant differences. More insights of this sEMG manifestation of sarcopenia were revealed by gender- and age-stratifications analyses.
Our results demonstrated that there are clear sEMG manifestations of altered muscle coordination in sarcopenic patients. More consistent force generation patterns were observed in the sarcopenic group, especially at lower contraction intensities. The novel ICDMC can quantify differences between sarcopenic and healthy muscle. These results warrant further research to further develop more accessible sarcopenia screening strategies in community settings based on electrophysiological measurements such as sEMG.
如果能及早诊断和治疗，肌肉减少症是一种与年龄相关的、隐匿的、致残但可治愈的退行性疾病。然而，对于社区环境来说，还没有一种易于使用且准确的早期筛查方法，而且这种方法不需要专门的人员。肌肉减少症的一个特征是肌肉纤维类型组成和运动单位放电模式的病理性变化。与医学成像和生物阻抗测量等其他筛查方法相比，表面肌电图（sEMG）由于其优越的可穿戴性和易用性，可能成为检测健康个体和肌肉减少症个体之间差异的有效工具，使其成为基于社区的肌肉减少症筛查的理想选择。我们的研究旨在探索可用于筛查或诊断肌肉减少症的 sEMG 生物标志物。
我们从 98 名健康社区居住的老年人和 55 名肌肉减少症老年人的六块前臂肌肉中采集了多通道 sEMG 信号。参与者以 20%和 50%最大自主收缩（MVC）的力度进行抓握任务。通过对各自 MVC 进行归一化并进行六边形分析，以评估多肌肉协调模式。提出了一种新的指标，即肌肉协调的内-外接圆距离（ICDMC），用于区分健康组和肌肉减少症组。我们利用非参数检验比较了两组之间的 ICDMC，认为 p 值小于 0.05 具有统计学意义。结果表明，在 20%MVC 时，均方根（RMS）、平均绝对值（MAV）、斜率符号变化（SSC）和波长（WL）的 ICDMC 存在统计学差异。通过性别和年龄分层分析，进一步揭示了肌肉减少症患者的 sEMG 表现。
我们的结果表明，肌肉减少症患者的肌肉协调有明显的 sEMG 表现。在肌肉减少症组中，尤其是在较低的收缩强度下，观察到更一致的力量产生模式。新的 ICDMC 可以量化肌肉减少症和健康肌肉之间的差异。这些结果需要进一步研究，以进一步开发基于肌电图等电生理测量的更易于使用的社区环境下的肌肉减少症筛查策略。
