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Motor Unit Number Estimation in Neuromuscular Disease

Published online by Cambridge University Press:  02 December 2014

Omid Rashidipour  and
K. Ming Chan
Omid Rashidipour
Affiliation:
Centre for Neuroscience, Division of Physical Medicine and Rehabilitation, Faculty of Medicine, University of Alberta, Edmonton, Alberta, Canada
K. Ming Chan
Affiliation:
Centre for Neuroscience, Division of Physical Medicine and Rehabilitation, Faculty of Medicine, University of Alberta, Edmonton, Alberta, Canada
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Abstract

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Motor unit number estimation (MUNE) is an electrophysiological method designed to quantify motor unit loss in target muscles of interest. Most of the techniques are noninvasive and are therefore well suited for longitudinal monitoring. In this brief review, we describe the more commonly used techniques and their applications in amyotrophic lateral sclerosis, poliomyelitis, spinal muscular atrophy and hereditary sensorimotor neuropathies. Findings in some of these studies offer important pathophysiological insights. Since conventional electrophysiologic methods are not sensible measures of motor neuronal loss, MUNE could play a potentially important role in the diagnosis, monitoring of disease progression and response to treatment in neuromuscular diseases in which motor unit loss is a major feature.

Résumé:

<span class='bold'>RÉSUMÉ</span>:

L’estimation du nombre d’unités motrices (ENUM) est une méthode électrophysiologique pour quantifier la perte d’unités motrices dans les muscles étudiés. La plupart des techniques non effractives sont donc appropriées pour la surveillance longitudinale. Dans cette courte revue, nous décrivons les techniques les plus fréquemment utilisées et leur application dans la sclérose latérale amyotrophique, la poliomyélite, l’atrophie musculaire spinale et les neuropathies sensitivomotrices héréditaires. Les observations provenant de ces études fournissent des indices physiopathologiques importants. Étant donné que les méthodes électrophysiologiques conventionnelles ne constituent pas une mesure sensible de la perte de neurones moteurs, l’ENUM pourrait jouer un rôle important dans le diagnostic, la surveillance de la progression de la maladie et la réponse au traitement dans les maladies neuromusculaires où la perte d’unités motrices est un élément important.

Type
Review Article
Information
Canadian Journal of Neurological Sciences , Volume 35 , Issue 2 , May 2008 , pp. 153 - 159
Copyright
Copyright © The Canadian Journal of Neurological 2008

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