Challenges to measure hydration, redness, elasticity and perfusion in the unloaded sacral region of healthy persons after supine position

• Skin physiology in the sacral area can be assessed by biophysical measurements.
• Hydration, redness, elasticity and perfusion measurement showed different reliability.
• The sacral skin showed dry values, low redness and elasticity like the neck region.
• Gender differences were only observed for skin elasticity, being higher in women.
• Transferring preclinical tests in a clinical application remains challenging.

Aim of the studyTo combine measurement methods of biophysical skin properties in a clinical setting and to measure baseline values in the unloaded sacral region of healthy persons after lying 30 min in supine position.MethodsHydration (Corneometer® CM 825), redness (Mexameter® MX 18), elasticity (Cutometer® MPA 580) and perfusion (PeriFlux System 5000) of the skin in the sacral region of 10 healthy participants (median age: 26.9 years) were measured consecutively in the laying position by two trained examiners.ResultsThe assessment duration for all four parameters lasted about 15 min. Intra-class correlation coefficients were overall moderate to strong (hydration r = 0.594, redness r = 0.817, elasticity r = 0.719, perfusion r = 0.591). Hydration (median 27.7 arbitrary units (AU)) mainly indicated dry skin conditions. Redness (median 158.5 AU) was low. Elasticity (median 0.880 AU) showed similar values as in the neck region. Perfusion (median 17.1 AU) showed values in the range of results reported in the literature.ConclusionBiophysical skin properties in the sacral region after supine position can be measured within periods of 15 min. The results provide baseline data for the skin of healthy persons as well as insights into skin-physiological variations. But it remains challenging to optimize measurement procedures and test protocols when transferring preclinical tests in a clinical application.