Margins of postural stability in Parkinson's disease: an application of control theory.

ABSTRACT: Introduction: Postural instability is a restrictive feature in Parkinson's disease (PD), usually assessed by clinical or laboratory tests. However, the exact quantification of postural stability, using stability theorems that take into account human dynamics, is still lacking. We investigated the feasibility of control theory and the Nyquist stability criterion-gain margin (GM) and phase margin (PM)-in discriminating postural instability in PD, as well as the effects of a balance-training program. Methods: Center-of-pressure (COP) data of 40 PD patients before and after a 4-week balance-training program, and 20 healthy control subjects (HCs) (Study1) as well as COP data of 20 other PD patients at four time points during a 6-week balance-training program (Study2)

SUBMITTER: Rahmati Z 

PROVIDER: S-EPMC10539597 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature