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Electrodiagnostics: MUNE and MUNIX as methods of estimating the number of motor units – biomarkers in lower motor neurone disease
Affiliations- Faculty of Medicine, Medical University of Warsaw, Poland
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Abstract
Routine quantitative electromyography is used for the assessment of the presence of lower motor neurone involvement and its consequences, including primary denervation and compensatory reinnervation of muscle fibres. However, it is not useful for the assessment of the motor unit number reserve. The need for a valid biomarker to evaluate lower motor neurone disease progression in such diseases as amyotrophic lateral sclerosis, and for use in clinical trials, has led to a number of studies of the methods that allow assessment of the number of motor units. In this review, motor unit number estimation (MUNE) methods with incremental stimulation and the recently developed motor unit number index (MUNIX) method, along with their technical and clinical aspects, are presented as methods which reflect motor unit loss in neurogenic processes. These electrodiagnostic tests may allow a valuable assessment of disease progression and the efficacy of new therapeutic methods in clinical trials in diseases with lower motor neurone degeneration.
Abstract
Routine quantitative electromyography is used for the assessment of the presence of lower motor neurone involvement and its consequences, including primary denervation and compensatory reinnervation of muscle fibres. However, it is not useful for the assessment of the motor unit number reserve. The need for a valid biomarker to evaluate lower motor neurone disease progression in such diseases as amyotrophic lateral sclerosis, and for use in clinical trials, has led to a number of studies of the methods that allow assessment of the number of motor units. In this review, motor unit number estimation (MUNE) methods with incremental stimulation and the recently developed motor unit number index (MUNIX) method, along with their technical and clinical aspects, are presented as methods which reflect motor unit loss in neurogenic processes. These electrodiagnostic tests may allow a valuable assessment of disease progression and the efficacy of new therapeutic methods in clinical trials in diseases with lower motor neurone degeneration.
Keywords
motor unit, motor unit number estimation, MUNE, motor unit number index, MUNIX, amyotrophic lateral sclerosis
About this articleTitle
Electrodiagnostics: MUNE and MUNIX as methods of estimating the number of motor units – biomarkers in lower motor neurone disease
Journal
Neurologia i Neurochirurgia Polska
Issue
Article type
Review Article
Pages
251-257
Published online
2019-06-17
Page views
1785
Article views/downloads
708
DOI
Pubmed
Bibliographic record
Neurol Neurochir Pol 2019;53(4):251-257.
Keywords
motor unit
motor unit number estimation
MUNE
motor unit number index
MUNIX
amyotrophic lateral sclerosis
Authors
Małgorzata Gaweł
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