Vol 53, No 4 (2019)
Review article
Published online: 2019-06-17
Submitted: 2018-12-05
Accepted: 2019-06-11
Get Citation

Electrodiagnostics: MUNE and MUNIX as methods of estimating the number of motor units – biomarkers in lower motor neurone disease

Małgorzata Gaweł
DOI: 10.5603/PJNNS.a2019.0026
·
Pubmed: 31206166
·
Neurol Neurochir Pol 2019;53(4):251-257.

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Vol 53, No 4 (2019)
Review article
Published online: 2019-06-17
Submitted: 2018-12-05
Accepted: 2019-06-11

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.

Get Citation

Keywords

motor unit, motor unit number estimation, MUNE, motor unit number index, MUNIX, amyotrophic lateral sclerosis

About this article
Title

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

Vol 53, No 4 (2019)

Pages

251-257

Published online

2019-06-17

DOI

10.5603/PJNNS.a2019.0026

Pubmed

31206166

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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