title: Quantification of Trunk Postural Stability Using Convex Polyhedron of the Time-Series Accelerometer Data.
abstract: Techniques to quantify postural stability usually rely on the evaluation of only two variables, that is, two coordinates of COP. However, by using three variables, that is, three components of acceleration vector, it is possible to describe human movement more precisely. For this purpose, a single three-axis accelerometer was used, making it possible to evaluate 3D movement by use of a novel method, convex polyhedron (CP), together with a traditional method, based on area of the confidence ellipse (ACE). Ten patients (Pts) with cerebellar ataxia and eleven healthy individuals of control group (CG) participated in the study. The results show a significant increase of volume of the CP (CPV) in Pts or CG standing on foam surface with eyes open (EO) and eyes closed (EC) after the EC phase. Significant difference between Pts and CG was found in all cases as well. Correlation coefficient indicates strong correlation between the CPV and ACE in most cases of patient examinations, thus confirming the possibility of quantification of postural instability by the introduced method of CPV.
authors.affiliation: Faculty of Biomedical Engineering, Czech Technical University in Prague, 272 01 Kladno, Czech Republic.
authors.forename: Roman
authors.initials: R
authors.lastname: Melecky
authors.affiliation: Faculty of Biomedical Engineering, Czech Technical University in Prague, 272 01 Kladno, Czech Republic.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Socha
authors.affiliation: Faculty of Biomedical Engineering, Czech Technical University in Prague, 272 01 Kladno, Czech Republic.
authors.forename: Patrik
authors.initials: P
authors.lastname: Kutilek
authors.affiliation: Faculty of Biomedical Engineering, Czech Technical University in Prague, 272 01 Kladno, Czech Republic.
authors.forename: Lenka
authors.initials: L
authors.lastname: Hanakova
authors.affiliation: Department of Rehabilitation and Spa Medicine, Faculty of Medicine, P. J. Šafárik University in Košice, 040 01 Košice, Slovakia.
authors.forename: Peter
authors.initials: P
authors.lastname: Takac
authors.affiliation: Faculty of Biomedical Engineering, Czech Technical University in Prague, 272 01 Kladno, Czech Republic.
authors.forename: Jakub
authors.initials: J
authors.lastname: Schlenker
authors.affiliation: Palacky University of Olomouc, Faculty of Physical Culture, 771 11 Olomouc, Czech Republic.
authors.forename: Zdenek
authors.initials: Z
authors.lastname: Svoboda
mesh_terms: D061725:Accelerometry / Q000379:methods*; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology*