SmartStride_FoG: Wearable System to Characterize Freezing of Gait using Stride-to-Stride Variability as a Biomarker

Freezing of Gait (FoG) is a debilitating motor symptom of individuals with Parkinson’s Disease (PD). The FoG is characterized by sudden interruptions in movement despite one’s intention to walk. Research suggests the presence of a critical Pre-FoG window, marked by progressive reduction in stride length while walking. In this study, we used SmartStride<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">FoG</inf>, a wearable device consisting of shoes with instrumented insoles integrated with Inertial Measurement Units to quantify one’s gait in terms of spatial and temporal gait parameters. These gait parameters were subsequently analyzed to evaluate one’s stride-to-stride variability. Results of our study carried out with fourteen individuals with PD (Group<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PD</inf>) and fourteen age-matched healthy counterparts (Group<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">H</inf>) showed the potential of SmartStride<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">FoG</inf> to quantify differences in the stride-to-stride variability of Group<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PD</inf> and Group<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">H</inf>. Furthermore, SmartStride<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">FoG</inf> could identify the pre-FoG window by sensing abrupt changes in stride-to-stride variability even before the occurrence of freezing episode. This shows the potential of SmartStride<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">FoG</inf> to offer promising biomarker i.e., stride-to-stride variability for detection and prediction of FoG that can have clinical significance. This in turn can guide interventionists to adopt necessary clinical strategies to overcome forthcoming FoG, making it a valuable tool for clinical intervention.