Torsional elasticity of human skin in vivo.

Measurements of physical properties of the intact human skin are described. An analysis of the measurements yields parameters that characterize elastic, visco-elastic and plastic properties. Between 6 and 61 years the elastic component of the extensibility of the skin under torsional conditions increases with age. The visco-elastic and plastic components are constant up to an age of fourty; at higher ages they show a small tendency to increase. Moduli of elasticity of the intact human skin derived from the torsion measurements yield values between about 2×10 N/m and 10 N/m, the highest values corresponding to the youngest age. From these values the moduli of elasticity of the elastic fibres in the living skin are estimated between about 2×10 N/m and 10 N/m. [ABSTRACT FROM AUTHOR]