Loss of selective wrist muscle activation in post-stroke patients

Loss of selective wrist muscle activation in post-stroke patients

van der Krogt, Hanneke (Leiden University Medical Center)
Kouwijzer, Ingrid (Leiden University Medical Center)
Klomp, A. (TU Delft Biomechatronics & Human-Machine Control; Leiden University Medical Center)
Meskers, Carel G.M. (Leiden University Medical Center)
Arendzen, J. Hans (Leiden University Medical Center)
de Groot, Jurriaan H. (Leiden University Medical Center)

2020

Purpose: Loss of selective muscle activation after stroke contributes to impaired arm function, is difficult to quantify and is not systematically assessed yet. The aim of this study was to describe and validate a technique for quantification of selective muscle activation of wrist flexor and extensor muscles in a cohort of post-stroke patients. Patterns of selective muscle activation were compared to healthy volunteers and test-retest reliability was assessed. Materials and methods: Activation Ratios describe selective activation of a muscle during its expected optimal activation as agonist and antagonist. Activation Ratios were calculated from electromyography signals during an isometric maximal torque task in 31 post-stroke patients and 14 healthy volunteers. Participants with insufficient voluntary muscle activation (maximal electromyography signal <3SD higher than baseline) were excluded. Results: Activation Ratios at the wrist were reliably quantified (Intraclass correlation coefficients 0.77–0.78). Activation Ratios were significantly lower in post-stroke patients compared to healthy participants (p < 0.05). Conclusion: Activation Ratios allow for muscle-specific quantification of selective muscle activation at the wrist in post-stroke patients. Loss of selective muscle activation may be a relevant determinant in assigning and evaluating therapy to improve functional outcome.Implications for Rehabilitation Loss of selective muscle activation after stroke contributes to impaired arm function, is difficult to quantify and is not systematically assessed yet. The ability for selective muscle activation is a relevant determinant in assigning and evaluating therapy to improve functional outcome, e.g., botulinum toxin. Activation Ratios allow for reliable and muscle-specific quantification of selective muscle activation in post-stroke patients.

biomechanics
electromyography
Muscle contraction
paresis
stroke

http://resolver.tudelft.nl/uuid:d7f405f7-8628-4d39-b769-4458a0e54e5c

https://doi.org/10.1080/09638288.2018.1509241

0963-8288

Disability and Rehabilitation, 42 (6), 779-787

Institutional Repository

journal article

© 2020 Hanneke van der Krogt, Ingrid Kouwijzer, A. Klomp, Carel G.M. Meskers, J. Hans Arendzen, Jurriaan H. de Groot