Dynamic Measures of Balance during a 90° Turn in Self-Selected Gait in Individuals with Mild Parkinson’s Disease

Abstract

The risk of falls is common in the aging and Parkinson’s disease (PD) populations. There is limited research on dynamic gait stability, i.e., margin of stability (MOS), in the PD population while turning. The purpose of this exploratory study was to examine the dynamic balance control in individuals with mild to moderate PD and healthy individuals while walking and performing 90° turns utilizing computerized three-dimensional gait analysis. Specifically, we examined the anteroposterior and mediolateral margins of stability and their effect on the dynamic balance during turning in participants. A total of 11 individuals with mild to moderate idiopathic PD and 10 healthy controls (CON) participated in this study. Individuals with PD were tested during the “on phase” of PD medication. The Vicon Nexus camera system, force plates, and Visual3D software were utilized for three-dimensional motion analysis of three right and three left turning trials. A mixed-model ANOVA was used to analyze the primary dependent variables of dynamic balance (p < 0.0028) and the secondary dependent variables of spatiotemporal gait parameters (p < 0.0056). No significant differences in the spatiotemporal parameters or dynamic balance variables were observed between the groups. Gait velocity, center of mass-center of pressure (COM–COP) inclination angle at midstance, and MOS variables showed marginally significant group differences. We found no differences in dynamic balance during gait while performing turns betweenthe healthy elderly and individuals with PD. This finding may be related to the early stage of disease progression in the PD group.