Abstract
To elucidate the relationship between various morphological motor unit parameters and electrophysiological findings obtained with single-fibre EMG (fibre density, FD) and macro-EMG, computer simulations were performed. FD and macro-MUP amplitude varied in parallel when fibre loss, fibre loss and corresponding motor unit territory shrinkage or fibre atrophy were simulated. When fibre loss and compensating reinnervation were produced the FD increased whereas the amplitude of the macro-MUP was unchanged. A discrepancy between the relative changes in these two EMG parameters seems to indicate uneven fibre distribution within the motor unit territory.
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Hilton-Brown, P., Nandekar, S.D. & Stålberg, E.V. Simulation of fibre density in single-fibre electromyography and its relationship to macro-EMG. Med. Biol. Eng. Comput. 23, 541–546 (1985). https://doi.org/10.1007/BF02455308
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DOI: https://doi.org/10.1007/BF02455308