Associations between skin structural and functional changes after loading in healthy aged females at sacral and heel...

Mechanical loading causes skin occlusion and deformation, which influences structural and functional skin properties. Aims of the study were to measure structural and functional skin parameters after loading at the sacral and heel skin and to describe possible associations.

A secondary data analysis based on a clinical trial with n = 15 aged women was conducted. Changes of transepidermal water loss, stratum corneum hydration, epidermal hydration, erythema, temperature, structural stiffness, elastic recovery, elastic function, and mean roughness after 120 min loading were described and compared. Spearman's rho (r_s) was used to estimate possible associations.

Loading caused an increase of transepidermal water loss, stratum corneum and epidermal hydration, erythema and temperature at sacral and heel skin. There was a decrease of median roughness at the heel skin surface (-8.5 (IQR -10.5 to 5.5) μm). Strongest positive associations were observed between changes of elastic function and elastic recovery (r_s = 0.9 at heel and sacral skin) and between changes of epidermal and stratum corneum hydration at both skin areas (r_s = 0.7 at sacral skin and r_s = 0.5 at the heel).

Two hours loading on a standard foam mattress leads to skin occlusion at the skin surface and mechanical deformation. Skin occlusion seems primarily to increase temperature, stratum corneum and epidermal hydration that may affect mechanical skin properties. Mechanical deformation seems to be responsible for the erythematous response of the dermal skin layer.