Abstract
BACKGROUND: Research concerning prevention of diabetic foot complications is critical. A novel in-shoe plantar sensory replacement unit (PSRU) has been developed that provides alert-based feedback derived from analyzing plantar pressure threshold measurements in real time. The purpose of this study was to compare the PSRU device to a gold standard pressure-sensing device (GS-PSD) to determine the correlation between concurrent measures of plantar pressure during walking. METHODS: The PSRU had an array of eight sensors with a range of 10-75 mm Hg and collected data at 4 Hz, whereas the GS-PSD had 99 sensors with a range of 1-112 mm Hg and collected data at 100 Hz. Based on an a priori power analysis, data were collected from 10 participants (3 female, 7 male) while walking over ground in both devices. The primary variable of interest was the number of data points recorded that were greater than 32 mm Hg (capillary arterial pressure--the minimum pressure reported to cause pressure ulcers) for each of the eight PSRU sensors and corresponding average recordings from the GS-PSD sensor clusters. Intraclass correlation coefficient (2,1) was used to compare data between the two devices. RESULTS: Compared with the GS-PSD, we found good-to-very-good correlations (r-value range 0.67-0.86; p-value range 0.01-0.05) for six of the PSRU's eight sensors and poor correlation for only two sensors (r = 0.41, p = .15; r = 0.38, p = .18) when measuring the number of data points recorded that were greater than 32 mm Hg. CONCLUSIONS: Based on the results of the present study, we conclude the PSRU provides analogous data when compared with a GS-PSD.