A SIMULATION STUDY ON NEUROMUSCULAR FACTORS AFFECTING CONSECUTIVE MOTOR UNIT ACTION POTENTIAL WAVESHAPE

Year 2020, Volume: 21 Issue: 4, 582 - 591, 28.12.2020

Kamil Savaş , Yasin Gökçe , Armando Trıgueros Nazmi Yaraş

https://doi.org/10.18038/estubtda.830739

Abstract

Quantification of consecutive motor unit potential (MUP) is used to diagnose and monitor the progress of neuromuscular pathologies in clinical applications. In this study, a detailed motor unit simulation was conducted to reveal and understand the factors affecting MUPs. Using a volume conductor model and real muscle parameters, normal and pathologic MUPs were created. The shape changes observed in consecutive MUPs, called jiggle, are calculated with a quantification method. Increased jitter duration and re-innervation percentage commonly observed during motor unit loss increase the jiggle value proportionally. Moreover, increasing fiber density changing different regions of a muscle bundle decreases the jiggle value. The blocking phenomena generally observed in re-innervated fibers affects the jiggle value similar to jitter duration. But, higher blocking levels (50%) of re-innervated motor fiber do not have an effect on jiggle value as lower levels of blocking (20%). In conclusion, simulation of pathological MUPs showed that it is useful for clinicians to understand the progress of a neuromuscular pathology and the factors affecting consecutive MUP wave shape.

Keywords

Motor Unit Action Potential, Neuromuscular Pathology, Motor Unit Instability, Motor Unit Simulation

Project Number

TDK-2019-4584

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