O128 Evaluation of muscle fibers diameter using analysis of motor unit potentials

Abstract

Objectives The study was to develop a method for evaluation of muscle fibers diameter by application an approximation of motor unit morphology using analysis of motor unit potentials (MUPs). Verify the utility and reliability. Method The principle of the approximation method rests upon decomposition of MUP into single fiber potentials to determine the morphology of muscle fibers generating these potentials and their diameters and distribution within motor unit territory. The typical and atypical MUPs of various shapes have been analysed. Results Using approximation method the morphology of motor unit generating the selected MUP has been determined including muscle fibers diameter. Contribution of each fiber to the MUP waveforms has been evaluated. Correlation between some characteristic MUP’s parameters and morphological features has been indicated. Conclusion MUP analysis using an approximation method emerged as a useful tool for the interpretation of MUPs. It enables to get an insight into motor unit morphology and therefore increases understanding of the way the motor unit structure correlates with function. The ability to quantify the fibers diameter can add significantly to the motor unit potentials examination. It may help study of muscle fiber diameter variability and thus compliment the muscle biopsy studies. Significance Extending the amount of information available from EMG examinations.