Ebenbichler Gerold, Habenicht Richard, Blohm Peter, Bonato Paolo, Kollmitzer Josef, Mair Patrick, Kienbacher Thomas
Karl-Landsteiner-Institute of Outpatient Rehabilitation Research, 1230 Vienna, Austria.
Department of Physical Medicine, Rehabilitation and Occupational Medicine, Medical University of Vienna, General Hospital of Vienna, 1090 Vienna, Austria.
Bioengineering (Basel). 2023 Feb 27;10(3):300. doi: 10.3390/bioengineering10030300.
As part of our quest for digital biomarkers of neuromuscular aging, and encouraged by recent findings in healthy volunteers, this study investigated if the instantaneous median frequency (IMDF) derived from back muscle surface electromyographic (SEMG) data monitored during cyclic back extensions could reliably differentiate between younger and older individuals with cLBP. A total of 243 persons with cLBP participated in three experimental sessions: at baseline, one to two days after the first session, and then again approximately six weeks later. During each session, the study participants performed a series of three isometric maximal voluntary contractions (MVC) of back extensors using a dynamometer. These were followed by an isometric back extension at 80% MVC, and-after a break-25 slow cyclic back extensions at 50% MVC. SEMG data were recorded bilaterally at L5 (multifidus), L2 (longissimus dorsi), and L1 (iliocostalis lumborum). Linear mixed-effects models found the IMDF-SEMG time-course changes more rapidly in younger than in older individuals, and more prominently in male participants. The absolute and relative reliabilities of the SEMG time-frequency representations were well compared between older and younger participants. The results indicated an overall good relative reliability, but variable absolute reliability levels. IMDF-SEMG estimates derived from cyclic back extensions proved to be successful in reliably detecting differences in back muscle function in younger vs. older persons with cLBP. These findings encourage further research, with a focus on assessing whether an IMDF-SEMG-based index could be utilized as a tool to achieve the preclinical detection of back muscle aging, and possibly predict the development of back muscle sarcopenia.
作为我们探索神经肌肉衰老数字生物标志物的一部分，并受到健康志愿者近期研究结果的鼓舞，本研究调查了在周期性背部伸展过程中监测的背部肌肉表面肌电图（SEMG）数据得出的瞬时中位频率（IMDF）是否能够可靠地区分患有慢性下腰痛（cLBP）的年轻人和老年人。共有243名患有cLBP的人参加了三个实验阶段：基线阶段、第一阶段后一到两天，以及大约六周后再次进行。在每个阶段，研究参与者使用测力计进行了一系列三次背部伸肌的等长最大自主收缩（MVC）。随后是在80%MVC下的等长背部伸展，休息后在50%MVC下进行25次缓慢的周期性背部伸展。在L5（多裂肌）、L2（背最长肌）和L1（腰髂肋肌）双侧记录SEMG数据。线性混合效应模型发现，IMDF-SEMG的时程变化在年轻人中比在老年人中更快，在男性参与者中更明显。在老年和年轻参与者之间对SEMG时频表示的绝对和相对可靠性进行了很好的比较。结果表明总体相对可靠性良好，但绝对可靠性水平存在差异。从周期性背部伸展得出的IMDF-SEMG估计值被证明能够成功地可靠检测出患有cLBP的年轻人和老年人背部肌肉功能的差异。这些发现鼓励进一步研究，重点是评估基于IMDF-SEMG的指标是否可以用作实现背部肌肉衰老临床前检测的工具，并可能预测背部肌肉少肌症的发展。
