Cargando…

Incongruity of Geometric and Spectral Markers in the Assessment of Body Sway

Different measurements of body oscillations in the time or frequency domain are being employed as markers of gait and balance abnormalities. This study investigates basic relationships within and between geometric and spectral measures in a population of young adult subjects. Twenty healthy subjects...

Descripción completa

Detalles Bibliográficos
Autores principales: Sozzi, Stefania, Ghai, Shashank, Schieppati, Marco
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9339954/
https://www.ncbi.nlm.nih.gov/pubmed/35923830
http://dx.doi.org/10.3389/fneur.2022.929132
_version_ 1784760288485048320
author Sozzi, Stefania
Ghai, Shashank
Schieppati, Marco
author_facet Sozzi, Stefania
Ghai, Shashank
Schieppati, Marco
author_sort Sozzi, Stefania
collection PubMed
description Different measurements of body oscillations in the time or frequency domain are being employed as markers of gait and balance abnormalities. This study investigates basic relationships within and between geometric and spectral measures in a population of young adult subjects. Twenty healthy subjects stood with parallel feet on a force platform with and without a foam pad. Adaptation effects to prolonged stance were assessed by comparing the first and last of a series of eight successive trials. Centre of Foot Pressure (CoP) excursions were recorded with Eyes Closed (EC) and Open (EO) for 90s. Geometric measures (Sway Area, Path Length), standard deviation (SD) of the excursions, and spectral measure (mean power Spectrum Level and Median Frequency), along the medio-lateral (ML) and antero-posterior (AP) direction were computed. Sway Area was more strongly associated than Path Length with CoP SD and, consequently, with mean Spectrum Level for both ML and AP, and both visual and surface conditions. The squared-SD directly specified the mean power Spectrum Level of CoP excursions (ML and AP) in all conditions. Median Frequency was hardly related to Spectrum Level. Adaptation had a confounding effect, whereby equal values of Sway Area, Path Length, and Spectrum Level corresponded to different Median Frequency values. Mean Spectrum Level and SDs of the time series of CoP ML and AP excursions convey the same meaning and bear an acceptable correspondence with Sway Area values. Shifts in Median Frequency values represent important indications of neuromuscular control of stance and of the effects of vision, support conditions, and adaptation. The Romberg Quotient EC/EO for a given variable is contingent on the compliance of the base of support and adaptation, and different between Sway Area and Path Length, but similar between Sway Area and Spectrum Level (AP and ML). These measures must be taken with caution in clinical studies, and considered together in order to get a reliable indication of overall body sway, of modifications by sensory and standing condition, and of changes with ageing, medical conditions and rehabilitation treatment. However, distinct measures shed light on the discrete mechanisms and complex processes underpinning the maintenance of stance.
format Online
Article
Text
id pubmed-9339954
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-93399542022-08-02 Incongruity of Geometric and Spectral Markers in the Assessment of Body Sway Sozzi, Stefania Ghai, Shashank Schieppati, Marco Front Neurol Neurology Different measurements of body oscillations in the time or frequency domain are being employed as markers of gait and balance abnormalities. This study investigates basic relationships within and between geometric and spectral measures in a population of young adult subjects. Twenty healthy subjects stood with parallel feet on a force platform with and without a foam pad. Adaptation effects to prolonged stance were assessed by comparing the first and last of a series of eight successive trials. Centre of Foot Pressure (CoP) excursions were recorded with Eyes Closed (EC) and Open (EO) for 90s. Geometric measures (Sway Area, Path Length), standard deviation (SD) of the excursions, and spectral measure (mean power Spectrum Level and Median Frequency), along the medio-lateral (ML) and antero-posterior (AP) direction were computed. Sway Area was more strongly associated than Path Length with CoP SD and, consequently, with mean Spectrum Level for both ML and AP, and both visual and surface conditions. The squared-SD directly specified the mean power Spectrum Level of CoP excursions (ML and AP) in all conditions. Median Frequency was hardly related to Spectrum Level. Adaptation had a confounding effect, whereby equal values of Sway Area, Path Length, and Spectrum Level corresponded to different Median Frequency values. Mean Spectrum Level and SDs of the time series of CoP ML and AP excursions convey the same meaning and bear an acceptable correspondence with Sway Area values. Shifts in Median Frequency values represent important indications of neuromuscular control of stance and of the effects of vision, support conditions, and adaptation. The Romberg Quotient EC/EO for a given variable is contingent on the compliance of the base of support and adaptation, and different between Sway Area and Path Length, but similar between Sway Area and Spectrum Level (AP and ML). These measures must be taken with caution in clinical studies, and considered together in order to get a reliable indication of overall body sway, of modifications by sensory and standing condition, and of changes with ageing, medical conditions and rehabilitation treatment. However, distinct measures shed light on the discrete mechanisms and complex processes underpinning the maintenance of stance. Frontiers Media S.A. 2022-07-18 /pmc/articles/PMC9339954/ /pubmed/35923830 http://dx.doi.org/10.3389/fneur.2022.929132 Text en Copyright © 2022 Sozzi, Ghai and Schieppati. https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Neurology
Sozzi, Stefania
Ghai, Shashank
Schieppati, Marco
Incongruity of Geometric and Spectral Markers in the Assessment of Body Sway
title Incongruity of Geometric and Spectral Markers in the Assessment of Body Sway
title_full Incongruity of Geometric and Spectral Markers in the Assessment of Body Sway
title_fullStr Incongruity of Geometric and Spectral Markers in the Assessment of Body Sway
title_full_unstemmed Incongruity of Geometric and Spectral Markers in the Assessment of Body Sway
title_short Incongruity of Geometric and Spectral Markers in the Assessment of Body Sway
title_sort incongruity of geometric and spectral markers in the assessment of body sway
topic Neurology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9339954/
https://www.ncbi.nlm.nih.gov/pubmed/35923830
http://dx.doi.org/10.3389/fneur.2022.929132
work_keys_str_mv AT sozzistefania incongruityofgeometricandspectralmarkersintheassessmentofbodysway
AT ghaishashank incongruityofgeometricandspectralmarkersintheassessmentofbodysway
AT schieppatimarco incongruityofgeometricandspectralmarkersintheassessmentofbodysway