Comparison of two measuring soles for recording the planar pressure distribution

Especially in the treatment of diabetic foot syndrome, a reduction of pressure in the affected areas is an essential treatment goal of orthopaedic shoe technology. The effectiveness of the supply is usually verified by pressure measurements in the shoe. So-called pressure distribution insoles are used for this. In some lectures and publications absolute pressure values are given as target values for successful treatment (e.g. 200 kPa). Among other things, it is overlooked that these target values were determined under firmly defined conditions and with a certain measuring system.

Therefore, the aim of this study was to determine and compare the pressure values for different everyday movements with two different, freshly calibrated, pressure distribution insoles (S1 and S2), which are frequently found on the German market. The figure shows the average maximum pressure using the example of walking in the listed foot regions.

In all foot regions not only the collected pressure values differ significantly (*, p<0.05) between the two tested pressure distribution insoles. There are also different pressure ratios between S1 and S2 in the different foot regions. Thus, approximately 75% higher values are measured at the forefoot with system S2 compared to system S1, while the difference in the forefoot is 135%. These conspicuities were also observed in the other everyday movements examined.

The pressure differences are caused by varied attributes between the different pressure insoles such as number of sensors, sensor type, sensor size,...

For this reason, a comparison of absolute pressure values is scientifically inadmissible.