The effects of accelerometer sensor position on freezing gait ratio parameters

Abstract

Freezing of gait (FoG) is an episodic gait pattern characterised by the inability to step that occurs on initiation or turning while walking for those with Parkinson’s disease (PD). This phenomenon is one of the most disabling yet poorly understood symptoms. It has been shown that tasks requiring bilateral limb coordination are the most likely to elicit FoG in the laboratory. Among the most promising tasks are stepping in place, walking and turning, and turning in place. Previously, the Freezing Ratio parameter (FoGratio) has been developed to objectively measure freezing severity[5]. Is FoG-ratio computed from a sensor located on the sternum or lower back comparable to the foot FoG-ratio during a walking turn? The Friedman test revealed that the FoG-ratios from different sensor locations are statistically different (p<0.001). Pairwise tests showed statistically significant differences between the. FoG_S-ratio and FoG_L-ratio (p<0.001), the FoG_S-ratio and FoG_IFratio (p=0.006), the FoG_L-ratio and FoG_IF-ratio (p=0.001), and the FoG_L-ratio and FoG_OF-ratio (p=0.001). The correlation analysis detected no significant relationship.