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Comparing two methods to record maximal voluntary contractions and different electrode positions in recordings of forearm extensor muscle activity : Refining risk assessments for work-related wrist disorders

Dahlqvist, Camilla LU ; Nordander, Catarina LU orcid ; Granqvist, Lothy LU ; Forsman, Mikael and Hansson, Gert Åke LU (2018) In Work 59(2). p.231-242
Abstract

BACKGROUND: Wrist disorders are common in force demanding industrial repetitive work. Visual assessment of force demands have a low reliability, instead surface electromyography (EMG) may be used as part of a risk assessment for work-related wrist disorders. For normalization of EMG recordings, a power grip (hand grip) is often used as maximal voluntary contraction (MVC) of the forearm extensor muscles. However, the test-retest reproducibility is poor and EMG amplitudes exceeding 100% have occasionally been recorded during work. An alternative MVC is resisted wrist extension, which may be more reliable. OBJECTIVE: To compare hand grip and resisted wrist extension MVCs, in terms of amplitude and reproducibility, and to examine the effect... (More)

BACKGROUND: Wrist disorders are common in force demanding industrial repetitive work. Visual assessment of force demands have a low reliability, instead surface electromyography (EMG) may be used as part of a risk assessment for work-related wrist disorders. For normalization of EMG recordings, a power grip (hand grip) is often used as maximal voluntary contraction (MVC) of the forearm extensor muscles. However, the test-retest reproducibility is poor and EMG amplitudes exceeding 100% have occasionally been recorded during work. An alternative MVC is resisted wrist extension, which may be more reliable. OBJECTIVE: To compare hand grip and resisted wrist extension MVCs, in terms of amplitude and reproducibility, and to examine the effect of electrode positioning. METHODS: Twelve subjects participated. EMG from right forearm extensors, from four electrode pairs, was recorded during MVCs, on three separate occasions. RESULTS: The group mean EMG amplitudes for resisted wrist extension were 1.2-1.7 times greater than those for hand grip. Resisted wrist extension showed better reproducibility than hand grip. CONCLUSIONS: The results indicate that the use of resisted wrist extension is a more accurate measurement of maximal effort of wrist extensor contractions than using hand grip and should increase the precision in EMG recordings from forearm extensor muscles, which in turn will increase the quality of risk assessments that are based on these.

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author
; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
electromyography, hand grip, normalization, resisted wrist extension, Technical risk assessment
in
Work
volume
59
issue
2
pages
12 pages
publisher
IOS Press
external identifiers
  • scopus:85044353987
  • pmid:29355119
ISSN
1051-9815
DOI
10.3233/WOR-172668
language
English
LU publication?
yes
id
2f13db55-c7d0-483d-abcd-018318031345
date added to LUP
2018-04-09 13:05:58
date last changed
2021-10-06 05:52:29
@article{2f13db55-c7d0-483d-abcd-018318031345,
  abstract     = {<p>BACKGROUND: Wrist disorders are common in force demanding industrial repetitive work. Visual assessment of force demands have a low reliability, instead surface electromyography (EMG) may be used as part of a risk assessment for work-related wrist disorders. For normalization of EMG recordings, a power grip (hand grip) is often used as maximal voluntary contraction (MVC) of the forearm extensor muscles. However, the test-retest reproducibility is poor and EMG amplitudes exceeding 100% have occasionally been recorded during work. An alternative MVC is resisted wrist extension, which may be more reliable. OBJECTIVE: To compare hand grip and resisted wrist extension MVCs, in terms of amplitude and reproducibility, and to examine the effect of electrode positioning. METHODS: Twelve subjects participated. EMG from right forearm extensors, from four electrode pairs, was recorded during MVCs, on three separate occasions. RESULTS: The group mean EMG amplitudes for resisted wrist extension were 1.2-1.7 times greater than those for hand grip. Resisted wrist extension showed better reproducibility than hand grip. CONCLUSIONS: The results indicate that the use of resisted wrist extension is a more accurate measurement of maximal effort of wrist extensor contractions than using hand grip and should increase the precision in EMG recordings from forearm extensor muscles, which in turn will increase the quality of risk assessments that are based on these.</p>},
  author       = {Dahlqvist, Camilla and Nordander, Catarina and Granqvist, Lothy and Forsman, Mikael and Hansson, Gert Åke},
  issn         = {1051-9815},
  language     = {eng},
  number       = {2},
  pages        = {231--242},
  publisher    = {IOS Press},
  series       = {Work},
  title        = {Comparing two methods to record maximal voluntary contractions and different electrode positions in recordings of forearm extensor muscle activity : Refining risk assessments for work-related wrist disorders},
  url          = {http://dx.doi.org/10.3233/WOR-172668},
  doi          = {10.3233/WOR-172668},
  volume       = {59},
  year         = {2018},
}