Castroflorio T, Farina D, Bottin A, Piancino M G, Bracco P, Merletti R
Specialization School of Orthodontics, Department of Biomedical Sciences and Human Oncology, Università di Torino, Torino, Italy.
J Oral Rehabil. 2005 Jun;32(6):411-7. doi: 10.1111/j.1365-2842.2005.01442.x.
This study addresses methodological issues on surface electromyographic (EMG) signal recording from jaw elevator muscles. The aims were (i) to investigate the sensitivity to electrode displacements of amplitude and spectral surface EMG variables, (ii) to analyse if this sensitivity is affected by the inter-electrode distance of the bipolar recording, and (iii) to investigate the effect of inter-electrode distance on the estimated amplitude and spectral EMG variables. The superficial masseter and anterior temporalis muscles of 13 subjects were investigated by means of a linear electrode array. The percentage difference in EMG variable estimates from signals detected at different locations over the muscle was larger than 100% of the estimated value. Increasing the inter-electrode distance resulted in a significant reduction of the estimation variability because of electrode displacement. A criterion for electrode placement selection is suggested, with which the sensitivity of EMG variables to small electrode displacements was of the order of 2% for spectral and 6% for amplitude variables. Finally, spectral and, in particular, amplitude EMG variables were very sensitive to inter-electrode distance, which thus should be fixed when subjects or muscles are compared in the same or different experimental conditions.
本研究探讨了从颌骨提升肌记录表面肌电图（EMG）信号的方法学问题。其目的包括：（i）研究幅度和频谱表面肌电图变量对电极位移的敏感性；（ii）分析这种敏感性是否受双极记录电极间距的影响；（iii）研究电极间距对估计的幅度和频谱肌电图变量的影响。通过线性电极阵列对13名受试者的浅层咬肌和颞肌前部进行了研究。肌肉不同位置检测到的信号在肌电图变量估计上的百分比差异大于估计值的100%。由于电极位移，增加电极间距会导致估计变异性显著降低。提出了电极放置选择标准，使用该标准时，频谱肌电图变量对小电极位移的敏感性约为2%，幅度变量约为6%。最后，频谱，尤其是幅度肌电图变量对电极间距非常敏感，因此在相同或不同实验条件下比较受试者或肌肉时，电极间距应固定。
