Nichtinvasive Erfassung elektrophysiologischer Parameter zur Beurteilung von Muskelermüdung unter isometrischen und dynamischen Kontraktionen

In the exploration of the mechanisms of chronical muscle pain, the assessment of neuro-muscular parameters of muscle fatigue under voluntary movement is of increasing importance. Therefor, a method allowing the non-invasive assessment of muscle fatigue under dynamic contractions (movement) was developed. Central electromyographic parameter in the assessment of local muscle fatigue is a decrease in the single motor unit conduction velocity. To allow the recording and evaluation of single motor unit potentials over a long duration, the method of high spatial resolution electromyography (HSR-EMG) was utilized and improved. In HSR-EMG, the spatial selectivity needed for the follow-up of the electrophysiological activity of motor units is gained by a combination of electrode arrays and spatial filtering. The thesis compends an adaptation of the hardware to the requirements of measurements of long duration under dynamic conditions as well as the development/investigation of methods suited for the interpretation of HSR-EMG signals gained under dynamic contractions.For measurements, a new design of a two-dimensional electrode array was developed. This electrode array can be attached to the skin while not affecting the subjects freedom of movement. Due to its high flexibility it can adopt to the curvature of muscles. A number of different electrode design was tested to gain an optimal electrical contact to the skin.In order to follow up the electrical activity of single motor units, a method is needed that allows the decomposition of the EMG signal into the contributions of the active motor units. For the decomposition a program based on a multi-channel cross correlation was developed, which is suited for the analysis of measurements of long duration.Under movement, changes in the geometry between muscle and electrode array lead to effects in the EMG signal, that do not correlate to physiological alterations. These geometrical effects and their consequences on electrophysiological parameters were investigated. The most important parameter in respect of dynamic HSR-EMG measuremets is the conduction velocity. On the other hand, geometrical effects can be used to determin changes in muscle length under dynamic conditions.The use of the developed methods was shown in the examples of two studies investigating muscle fatigue in subjects with chronic, respectively experimental muscle pain.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2005

Author dc:creator

• Schulte, Elke

Contributors dc:contributor

• Rau, Günter

• info:eu-repo/classification/ddc/600
• Technik
• Elektromyographie
• Muskel
• Ermüdung
• Motorische Einheit
• Elektrodenarray
• Erregungsweiterleitungsgeschwindigkeit
• dynamische Kontraktion
• Muskelermüdung
• electromyography
• muscle fatigue
• motor unit
• electrode array
• conduction velocity

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-120871%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:59055