Analysis of surface EMG spike shape across different levels of isometric force

Signal processing of the surface electromyogram to gain insight into neuromuscular physiology

“…Several methods to quantify or assess MU synchronization from a larger population of active MUs have been proposed using surface electromyography. They include, among others, spike shape analysis (Gabriel et al 2007), mean frequency (Kleine et al 2001), and full-wave rectification and frequency analysis (Halliday et al 1999). While the information about MU synchronization is dependent on central physiological factors, the sEMG is also influenced by peripheral factors such as MUAP shape and volume conduction properties.…”

Motor unit synchronization during fatigue: A novel quantification method

“…Several methods to estimate MU synchronization of a larger population of active MUs have been proposed using bipolar surface EMG (sEMG) techniques (Gabriel et al, 2007;Farina et al, 2002;Kleine et al, 2001;Halliday et al, 1999;Milner-Brown et al, 1973b). However, the results of the earliest methods have been found to be ''incorrect'' when compared to the cross-correlation method (Semmler and Nordstrom, 1999), mainly due to a rectification artifact (noise) of the sEMG (Yue et al, 1995).…”

Differences in EMG spike shape between individuals with and without non-specific arm pain

“…As an alternative, surface electromyography (SEMG) data acquisition is less invasive, and SEMG systems are commonly available in many laboratories. As such, spike shape analysis of SEMG data (Gabriel et al, 2007) may be a valuable evaluation tool if it is deemed to be useful in differentiating neurogenic from myogenic disorders. Fig.…”

“…The variables computed to perform a spike shape analysis include mean spike amplitude (MSA), mean spike frequency (MSF), mean spike slope (MSS), mean spike duration (MSD) and mean number of peaks per spike (MNPPS). The specific algorithms used to compute these measures are described in detail in Gabriel et al (2007), and are briefly presented in the methods section of this paper.…”

“…For example, the changes in spike shape associated with increased recruitment (increase in MSA, MSF, MSS, MNPPS; decrease in MSD) are different from those associated with synchronization (increase in MSA, MSS, MSD; decrease in MSF and MNPPS), a distinction that is not possible with traditional time and frequency-based analyses of SEMG (see Table 1). The reliability of SEMG spike shape parameters has been previously established to be good (ICCs ranged from 0.76 to 0.93) (Gabriel, 2000), and spike shape measures have recently been shown to change in a predictable manner with increases in isometric force production in the biceps brachii (BB) muscle (Gabriel et al, 2007). This method has Table 1 Predicted changes in the surface electromyography (SEMG) spike shape parameters across increasing force output.…”