Quantitative assessment of simultaneous capacitive and resistive plantar pressure measurements during walking

Plantar pressure data were collected simultaneously, during walking, from capacitive and resistive in-shoe pressure measurement systems. Overall mean peak pressure recordings from the resistive system were 32%, 20% and 14% greater than recordings from the capacitive system, at the heel, central metatarsal heads, and great toe, respectively. Placement of one system's insoles above or below the other's somewhat affected peak pressure measurements from both systems, while calibration via air bladder or single limb standing techniques somewhat affected resistive measurements as well. Capacitive measurement variability was 60%, 20% and 22% lower than resistive measurement variability, at the heel, central metatarsal heads, and great toe, respectively. Both systems tended to exhibit greater variability when capacitive insoles were placed above resistive insoles; however, the effects on variability of the experimental insole arrangements were well overshadowed by the overall variability differences between systems.