The effect of probe to skin contact force on Cutometer MPA 580 measurements.

The purpose of this study is to test the hypothesis that increasing the force applied on the skin by the Cutometer MP580 probe will result in a decrease in the skin elasticity measures. Specifically, this study assessed the probe intrinsic weight plus the addition of a light mass (10 g and 20 g), a moderate mass (50 g and 100 g) and a high mass (200 g and 500 g) on skin elasticity measures. Primary outcome measures Uv, Ur, Uf, Ue and Ua, along with calculated measures Uv/Uf, Ua/Uf and Ur/Uf were assessed under each loading condition. A general linear model ANOVA with repeated measures was used to assess for differences in each outcome measure between each loading condition. Thirty-two patients were enrolled and all completed the testing. For all primary variables except Uv (p < 0.001), there was no statistically significant effect of adding a light mass to the probe. There was a significant effect of the addition of a moderate and heavy mass for all variables (p < 0.005) except Ue/Uf. These results suggest that the addition of a low mass results in no significant effect on outcome measures. However, if moderate-to-heavy additional force is applied to the probe, the outcome measures are significantly altered. Of all the variables, Ue/Uf appears to be influenced the least by alterations in force. Users should ensure light contact is made between the skin and probe during testing to avoid a false alteration in outcome measures of skin elasticity.