Dynamic Balance in the Gait Cycle Prior to a 90° Turn in Individuals with Parkinson’s Disease

Abstract

Parkinson’s disease (PD), a prevalent neurodegenerative condition, is associated with fall-related injuries. Falls often occur during mobility tasks such as turning while walking. There is a paucity of research on the biomechanical etiology of falls, specifically, the control of dynamic balance during turns. The purpose of this study was to analyze dynamic stability, as measured by the margin of stability (MOS), during the gait cycle preceding a 90-degree turn during walking in persons with PD. Thirteen individuals with mild to moderate idiopathic PD and 10 healthy matched controls (CON) participated. Instrumented gait analysis was conducted during walking while performing 90-degree turns using the Plug-in Gait model and Vicon Nexus motion capture software. MOS variables at first double support, midstance, and second double support of the gait cycle preceding the turn were examined. The MOS variables and spatiotemporal gait parameters were compared between PD and CON using a multilevel mixed model ANOVA; post hoc analyses were conducted using two-sample t-tests. There were no differences in spatiotemporal gait parameters between groups. The PD group demonstrated significantly greater medio-lateral (M/L) MOS compared to CON for most variables. The changes seen in the M/L MOS in the PD group may reflect compensatory changes to increase dynamic stability during the gait cycle preceding a turn.