A quantitative characterization of postural sway during human quiet standing using a thin pressure distribution measurement system.

The accuracy of the center of pressure (CoP) measurement during human quiet standing using an ultra-thin film pressure measurement system (Tekscan, I-Scan) was examined. To this end, CoP sway was measured simultaneously by I-Scan and a force platform (FP) to quantify differences in CoP obtained by the two methods. The sway amplitudes of I-Scan were slightly smaller than those of FP. The differences were systematic, allowing us to identify a filter that could bring every CoP trajectory of I-Scan close to that of FP. We concluded that, with the use of the filter, I-Scan could be used for accurate measurement of CoP sway during quiet standing.