Kinematics during turning differs in Parkinson’s disease patients with and those without freezing of gait

Turning exacerbates gait difficulties and can trigger freezing of gait (FOG) in Parkinson’s disease (PD), yet its underlying mechanisms remain poorly understood. We investigated spatiotemporal gait parameters during turning in 10 healthy elderly controls, 10 PD patients without FOG (PD-P), and 10 PD patients with FOG (FOG-P), analyzing turns at 90°, 180°, and 360° using a Bayesian generalized linear model. PD-P patients showed decreased stride width in the internal leg and increased width in the external leg, while FOG-P patients exhibited reduced step and stride lengths bilaterally. Both PD groups predominantly used a step-out or mixed-turning strategy and required more time and steps to complete larger amplitude turns. Notably, PD-P struggled with mediolateral adjustments, whereas FOG-P faced challenges with anteroposterior adaptations. These findings enhance our understanding of turning-related gait impairments in PD and FOG, with implications for personalized rehabilitation and future study designs.