BALLISTOMETER FOR STUDY OF PLASTOELASTIC PROPERTIES OF SKIN

[摘要] The ballistrometer was based on the drop impact of a body onto a stationary surface. A collision in 1 dimension was provoked by allowing a hard body to drop from a given height onto the skin surface to be tested. After the collision, the impacting body underwent a variable number of rebounds decreasing in amplitude. By measuring the height of the rebounds, the amount of energy returned by the tissue was calculated in terms of coefficient of restitution (e). The equipment, consisting of a hammer unit, a feeder-amplifier and a plotter, was described. Ballistometry was carried out on skin areas of 46 normal subjects ranging in age from 8-80 yr, as well as on pathologic and cadaveric skin. The results showed a progressive decrease of e with advancing age, and differences related to various skin regions. The tests performed on pathologic skin showed a lowered e in epidermal hyperplasia, hyperkeratosis, sclerosis and dermal infiltration. An increase of e was observed when a high water content was present in the skin.