Jitter patterns in conventional concentric needle electromyography recordings of regenerating motor units.
clinical electrophysiology
concentric needle electromyography
jitter
motor unit potential
neuromuscular junction
reinnervation
Journal
Muscle & nerve
ISSN: 1097-4598
Titre abrégé: Muscle Nerve
Pays: United States
ID NLM: 7803146
Informations de publication
Date de publication:
11 2020
11 2020
Historique:
received:
03
03
2020
revised:
08
07
2020
accepted:
19
07
2020
entrez:
12
11
2020
pubmed:
13
11
2020
medline:
5
1
2021
Statut:
ppublish
Résumé
The time interval between two potential components of the same motor unit potential (MUP) is measured for jitter analysis. Enhanced jitter is generally thought to result from impaired neuromuscular transmission as occurs in myasthenia gravis or during reinnervation. Within a database of conventional video-electromyography (EMG) recordings 4 MUP with peculiar jitter patterns were identified. In 1 spontaneously discharging MUP, massive and chaotic jitter was seen with a mean consecutive difference (MCD) of 9.3 ms. In 2 spontaneously discharging MUP a certain potential subgroup jittered relative to the other part(s) of the MUP (MCD 2.0 and 3.3 ms). A jittering satellite was detected in a fourth voluntarily recruited MUP (MCD 0.6 ms). These different jitter patterns recorded with conventional EMG technique may mainly result from dysmyelination. A new look at the contribution of dysmyelination to abnormal jitter is also warranted in single fiber EMG recordings.
Sections du résumé
BACKGROUND
The time interval between two potential components of the same motor unit potential (MUP) is measured for jitter analysis. Enhanced jitter is generally thought to result from impaired neuromuscular transmission as occurs in myasthenia gravis or during reinnervation.
METHODS
Within a database of conventional video-electromyography (EMG) recordings 4 MUP with peculiar jitter patterns were identified. In 1 spontaneously discharging MUP, massive and chaotic jitter was seen with a mean consecutive difference (MCD) of 9.3 ms. In 2 spontaneously discharging MUP a certain potential subgroup jittered relative to the other part(s) of the MUP (MCD 2.0 and 3.3 ms). A jittering satellite was detected in a fourth voluntarily recruited MUP (MCD 0.6 ms).
RESULTS
These different jitter patterns recorded with conventional EMG technique may mainly result from dysmyelination.
CONCLUSIONS
A new look at the contribution of dysmyelination to abnormal jitter is also warranted in single fiber EMG recordings.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
593-596Informations de copyright
© 2020 Wiley Periodicals LLC.
Références
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