Design of SmartWalk for Estimating Implication of Pathway With Turn and Task Condition on Postural and Gait Indices: Relevance to Fear of Fall.

Fear of Fall (FoF) is often associated with postural and gait abnormalities leading to decreased mobility in individuals with Parkinson's Disease (PD). The variability in knee flexion (postural index) during heel-strike and toe-off events while walking can be related to one's FoF. Depending on the progression of the disease, gait abnormality can be manifested as start/turn/stop hesitation, etc. adversely affecting one's cadence along with an inability to transfer weight from one leg to the other. Also, task demands can have implications on one's gait and posture. Given that individuals with PD often suffer from FoF and their dynamic balance is affected by task conditions and pathways, in- depth investigation is warranted to understand the implications of task condition and pathways on one's gait and posture. This necessitates use of portable, wearable device that can capture one's gait-related indices and knee flexion in free-living conditions. Here, we have designed a portable, wearable and cost-effective device (SmartWalk) comprising of instrumented Shoes integrated with knee flexion recorder units. Results of our study with age-matched groups of healthy individuals (GrpH) and those with PD (GrpPD) showed the potential of SmartWalk to estimate the implication of task condition, pathways (with and without turn) and pathway segments (straight and turn) on one's knee flexion and gait with relevance to FoF. The knee flexion and gait-related indices were found to strongly corroborate with clinical measure related to FoF, particularly for GrpPD, serving as pre-clinical inputs for clinicians.