title: Between-day reliability of triceps surae responses to standing perturbations in people post-stroke and healthy controls: A high-density surface EMG investigation.
abstract: The reliability of triceps surae electromyographic responses to standing perturbations in people after stroke and healthy controls is unknown. High-Density surface Electromyography (HDsEMG) is a technique that records electromyographic signals from different locations over a muscle, overcoming limitations of traditional surface EMG such as between-day differences in electrode placement. In this study, HDsEMG was used to measure responses from soleus (SOL, 18 channels) and medial and lateral gastrocnemius (MG and LG, 16 channels each) in 10 people after stroke and 10 controls. Timing and amplitude of the response were estimated for each channel of the grids. Intraclass Correlation Coefficient (ICC) and normalized Standard Error of Measurement (SEM%) were calculated for each channel individually (single-channel configuration) and on the median of each grid (all-channels configuration). Both timing (single-channel: ICC=0.75-0.96, SEM%=5.0-9.1; all-channels: ICC=0.85-0.97; SEM%=3.5-6.2%) and amplitude (single-channel: ICC=0.60-0.91, SEM%=25.1-46.6; ICC=0.73-0.95, SEM%=19.3-42.1) showed good-to-excellent reliability. HDsEMG provides reliable estimates of EMG responses to perturbations both in individuals after stroke and in healthy controls; reliability was marginally better for the all-channels compared to the single-channel configuration.
authors.affiliation: Graduate program in Rehabilitation Science, University of British Columbia, Vancouver, Canada; Laboratorio di Ingegneria del Sistema Neuromuscolare (LISiN), Dipartimento di Elettronica e Telecomunicazioni, Politecnico di Torino, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Gallina
authors.affiliation: Graduate program in Rehabilitation Science, University of British Columbia, Vancouver, Canada.
authors.forename: C L
authors.initials: CL
authors.lastname: Pollock
authors.affiliation: Laboratorio di Ingegneria del Sistema Neuromuscolare (LISiN), Dipartimento di Elettronica e Telecomunicazioni, Politecnico di Torino, Italy; Escola de Educação Física e Desportos, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil.
authors.forename: T M
authors.initials: TM
authors.lastname: Vieira
authors.affiliation: Department of Physical Therapy, University of British Columbia, Vancouver, Canada.
authors.forename: T D
authors.initials: TD
authors.lastname: Ivanova
authors.affiliation: Department of Physical Therapy, University of British Columbia, Vancouver, Canada. Electronic address: jayne.garland@ubc.ca.
authors.forename: S J
authors.initials: SJ
authors.lastname: Garland
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D015203:Reproducibility of Results; D020521:Stroke / Q000503:physiopathology*
keywords: High-density surface electromyography; Perturbation; Posture; Reliability; Stroke