Development and validation of a wireless, low-cost device for dual measurement of in-shoe plantar pressure and temperature in high-risk diabetic feet

Abstract

This study aims to evaluate the performance of an innovative in-shoe sensing device against the FScan system. Across five trials, the novel device demonstrated consistently strong correlations with FScan peak pressure readings (r =0.801, r = 0.978, r=0.813, r=0.887, r =0.944). Superimposed peak-pressure plots revealed highly similar waveform patterns between the two systems. Error-based metrics also supported this equivalence. Root Mean Squared Logarithmic Error values similarly suggested consistent predictive agreement. Temperature-sensing performance was assessed by comparing in-shoe sensor readings by the novel device with thermal-camera measurements. The thermal camera detected an average temperature change of 3.7°C, whereas the in-shoe sensor recorded an average change of 0.67°C. There was substantial variability in both systems, with higher variation observed in the in-shoe sensor than in the thermal camera. Despite variability, temperature and pressure measurements from the novel device were strongly correlated (r =0.87). In conclusion, the new device provides pressure measurements comparable to the FScan system and appears promising for monitoring foot health.