How can neurophysiological studies help with movement disorders characterization in clinical practice? A review

Talyta GRIPPE; Natalia Spinola Costa da CUNHA; Pedro Renato de Paula BRANDÃO; Rubens Nelson Morato FERNANDEZ; Francisco Eduardo Costa CARDOSO

doi:10.1590/0004-282X20190195

Arquivos de Neuro-Psiquiatria, Table of Contents

CC BY-NC-ND 4.0 · Arq Neuropsiquiatr 2020; 78(08): 512-522
DOI: 10.1590/0004-282X20190195

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How can neurophysiological studies help with movement disorders characterization in clinical practice? A review

Como os exames neurofisiológicos podem ajudar na caracterização dos transtornos do movimento na prática clínica? Uma revisão

Talyta GRIPPE

¹Centro Universitário de Brasília, Faculdade de Medicina, Brasília DF, Brazil.

²Hospital de Base do Distrito Federal, Departamento de Neurologia, Brasília DF, Brazil.

,

Natalia Spinola Costa da CUNHA

³Hospital da Criança de Brasília, Departamento de Neuropediatria, Brasília DF, Brazil.

,

Pedro Renato de Paula BRANDÃO

⁴Universidade de Brasília, Laboratório de Neurociência e Comportamento, Brasília DF, Brazil.

,

Rubens Nelson Morato FERNANDEZ

²Hospital de Base do Distrito Federal, Departamento de Neurologia, Brasília DF, Brazil.

,

Francisco Eduardo Costa CARDOSO

⁵Universidade Federal de Minas Gerais, Departamento de Clínica Médica, Unidade de Distúrbios do Movimento, Belo Horizonte MG, Brazil.

› Author Affiliations

Abstract

ABSTRACT

Background: Neurophysiological studies are ancillary tools to better understand the features and nature of movement disorders. Electromyography (EMG), together with electroencephalography (EEG) and accelerometer, can be used to evaluate a hypo and hyperkinetic spectrum of movements. Specific techniques can be applied to better characterize the phenomenology, help distinguish functional from organic origin and assess the most probable site of the movement generator in the nervous system. Objective: We intend to provide an update for clinicians on helpful neurophysiological tools to assess movement disorders in clinical practice. Methods: Non-systematic review of the literature published up to June 2019. Results: A diversity of protocols was found and described. These include EMG analyses to define dystonia, myoclonus, myokymia, myorhythmia, and painful legs moving toes pattern; EMG in combination with accelerometer to study tremor; and EEG-EMG to study myoclonus. Also, indirect measures of cortical and brainstem excitability help to describe and diagnose abnormal physiology in Parkinson's disease, atypical parkinsonism, dystonia, and myoclonus. Conclusion: These studies can be helpful for the diagnosis and are usually underutilized in neurological practice.

RESUMO

Introdução: Os estudos neurofisiológicos são métodos auxiliares para compreender melhor as características e a natureza dos distúrbios do movimento. A eletromiografia (EMG), em associação com o eletroencefalograma (EEG) e o acelerômetro, podem ser utilizados para avaliar um espectro de movimentos hipo e hipercinéticos. Técnicas específicas podem ser aplicadas para melhor caracterizar a fenomenologia, ajudar a distinguir a origem psicogênica da orgânica e avaliar o local mais provável de geração do movimento no sistema nervoso. Objetivo: Pretendemos fornecer ao clínico uma atualização sobre ferramentas neurofisiológicas úteis para avaliar distúrbios do movimento na prática clínica. Métodos: Revisão não sistemática da literatura publicada até junho de 2019. Resultados: Uma diversidade de protocolos foi encontrada e descrita. Dentre eles, inclui-se o uso de EMG para a definição do padrão de distonia, mioclonia, mioquimia, miorritmia e painfull legs moving toes, além do uso de EMG em associação ao acelerômetro para avaliar tremor e, em associação ao EEG para avaliar mioclonia. Ademais, técnicas para medida indireta de excitabilidade cortical e do tronco encefálico ajudam a descrever e diagnosticar a fisiologia anormal da doença de Parkinson, parkinsonismo atípico, distonia e mioclonia. Conclusão: Esses estudos podem ser úteis para o diagnóstico e geralmente são subutilizados na prática neurológica.

Keywords:

Movement Disorders - Neurophysiology - Dystonia - Tremor - Myoclonus

Palavras-chave:

Transtornos dos Movimentos - Neurofisiologia - Distonia - Tremor - Mioclonia

Full Text

References

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