The Position of Innervation Zones in the Biceps Brachii Investigated by Surface Electromyography
01 Jan 1985-IEEE Transactions on Biomedical Engineering (IEEE Trans Biomed Eng)-Vol. 32, Iss: 1, pp 36-42
TL;DR: A computer program was developed, which automatically determined the potential source by applying a correlation calculation and a linear regression to the recorded signals and clarified the distribution of the innervation zones in the biceps brachii.
Abstract: A linear surface electrode array placed along the muscle fibers detects motor unit action potentials propagating bilaterally to the tendons. The location of the propagation source is presumed to mark an innervation zone. We developed a computer program, which automatically determined the potential source by applying a correlation calculation and a linear regression to the recorded signals. The spacing between the contacts in the electrode array was 5.0 mm, whereas for some recordings the histogram indicating the position of estimated source had a sharp peak concentrated in a 1.0 mm area. In the biceps brachii some subjects were found to have two innervation zones separated by 10-20 mm. The peaks corresponding to the innervation zones differentially changed their histogram scores according to the contraction force. We also constructed an electrode assembly, which had four columns of the linear electrode arrays, and clarified the distribution of the innervation zones in the biceps brachii.
Citations
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TL;DR: This study identifies optimal electrode sites for muscles in the lower extremity by providing a standard landmarking technique for the localization of the IZ of each muscle so that surface EMG electrodes can be properly positioned between the I Z and a tendon.
539 citations
Cites background from "The Position of Innervation Zones i..."
...This issue has been studied in several works (Masuda et al., 1985a,b; Zuniga et al., 1970) that have shown how such geometrical artifact determines alterations of the EMG amplitude variables not related to real modification of the muscle activity....
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...…use of multichannel electrode arrays, a number of investigations have shown how EMG variable estimations vary along the muscle length (i.e. with respect to electrode positioning) (Masuda et al., 1985b; Merletti et al., 1999, 2001b; Rainoldi et al., 2000; Roy et al., 1986; Sadoyama et al., 1985)....
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TL;DR: The aim of this review is to present the state of the art of the technology of detection and conditioning systems for surface electromyography (sEMG) in terms of electrode classification, impedance, noise, transfer function, and the spatial filtering effect of surface electrode configurations on the recorded sEMG signal.
321 citations
Cites background from "The Position of Innervation Zones i..."
...The first example of application of spatial sampling was the development of the linear electrode arrays (Broman et al, 1985; Masuda et al., 1985a, b)....
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TL;DR: In this review, the basic principles of operation of linear electrode arrays for the detection of surface EMG signals are described, together with their most relevant current applications.
274 citations
Cites background from "The Position of Innervation Zones i..."
...[3] first proposed linear arrays with up to 16 electrodes (15 single differential filters) and indicated important applications of these systems for the investigation of anatomical muscle properties [5,6] and the estimation of muscle fiber conduction velocity (CV) [7,8]....
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...Reprinted from [6] with permission, 1985 IEEE....
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...[6] T....
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TL;DR: The results do not support the establishment of a general relationship between spectral EMG variables and torque or recruitment strategy and indicate that volume conductor properties play an important role as confounding factors that may mask any relation between EMG spectral variables and estimated CV as a size principle parameter during ramp contractions.
Abstract: During isometric contractions of increasing strength, motor units (MUs) are recruited by the central nervous system in an orderly manner starting with the smallest, with muscle fibers that usually show the lowest conduction velocity (CV). Theory predicts that the higher the velocity of propagation of the action potential, the higher the power at high frequencies of the detected surface signal. These considerations suggest that the power spectral density of the surface detected electromyogram (EMG) signal may give indications about the MU recruitment process. The purpose of this paper is to investigate the potential and limitations of spectral analysis of the surface EMG signal as a technique for the investigation of muscle force control. The study is based on a simulation approach and on an experimental investigation of the properties of surface EMG signals detected from the biceps brachii during isometric linearly increasing torque contractions. Both simulation and experimental data indicate that volume conductor properties play an important role as confounding factors that may mask any relation between EMG spectral variables and estimated CV as a size principle parameter during ramp contractions. The correlation between spectral variables and CV is thus significantly lower when the MU pool is not stable than during constant-torque isometric contractions. Our results do not support the establishment of a general relationship between spectral EMG variables and torque or recruitment strategy.
273 citations
TL;DR: Both the discharge pattern and muscle fiber properties of individual motor units can currently be analyzed non-invasively and this review presents the conditions and methodologies which allow the investigation of motor units with surface EMG.
264 citations
References
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TL;DR: The myoelectric signal is the electrical manifestation of the neuromuscular activation associated with a contracting muscle and the lack of a proper description of the ME signal is probably the greatest single factor which has hampered the development of electromyography (EMG) into a precise discipline.
Abstract: The myoelectric (ME) signal is the electrical manifestation of the neuromuscular activation associated with a contracting muscle. It is an exceedingly complicated signal which is affected by the anatomical and physiological properties of muscles, the control scheme of the peripheral nervous system, as well as the characteristics of the instrumentation that is used to detect and observe it. Most of the relationships between the ME signal and the properties of a contracting muscle which are presently employed have evolved serendipitously. The lack of a proper description of the ME signal is probably the greatest single factor which has hampered the development of electromyography (EMG) into a precise discipline.
631 citations
01 Nov 1970
559 citations
"The Position of Innervation Zones i..." refers methods in this paper
...Then, the detected signals are attenuated by a filter, which results from the electrode configuration and has nulls at frequencies determined by the electrode spacing and the conduction velocity [1]....
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TL;DR: The spatial selectivity of bipolar electrodes, and its possible enhancement by linear filtering techniques, are discussed, and predicted e.m. power spectra are compared with some practical measurements on biceps brachii muscle in normal subjects.
Abstract: A 2-dimensional conducting-paper analogue and a 3-dimensional field-theory model are used to investigate the influence of electrode spacing and size on the waveshape and frequency spectrum of the signal detected by bipolar surface electrodes, when an action potential propagates in a muscle fibre below the skin surfce. The spatial selectivity of bipolar electrodes, and its possible enhancement by linear filtering techniques, are then discussed. Finally, predicted e.m.g power spectra are compared with some practical measurements on biceps brachii muscle in normal subjects.
144 citations
TL;DR: A new approach to the measurement of muscle fiber conduction velocity by surface electromyography (EMG) is developed, based upon a triple surface-electrode configuration, which is equally suited to a 16-bit microprocessor, without any need for hardware multiplication or floating-point facilities.
Abstract: A new approach to the measurement of muscle fiber conduction velocity by surface electromyography (EMG) is developed, based upon a triple surface-electrode configuration. Unlike previously reported methods, it does not require the Fourier transformation of raw EMG data, and can be implemented on-line on a simple digital computer. Although programmed here on a PDP-11 machine, the algorithms developed are equally suited to a 16-bit microprocessor, without any need for hardware multiplication or floating-point facilities. Accurate conduction velocity estimates may be obtained every few seconds.
110 citations