Evaluation of Biomechanical Properties of Human Skin

W ith the exception of the skeleton and the musculature, the skin is the largest organ, being about 1.7 m2 in area and approxi-mately 4 kg in weight, or about 5.5 % body mass. ’ Be-cause it represents the outward appearance, skin has great social importance, but only when affected by se-rious disease do we fully realize the extent and impor-tance of its many other, more basic functions. Our skin is multifunctional and has consequently an extremely complex structure. It is multilayered with convoluted and often indistinct interlayer boundaries, and its properties are different in different directions. Its structure and appropriate function vary with body site. The properties of skin also vary with the rate of application of stress and the length of time over which the stress is maintained, and are very sensitive to am-bient conditions, age, and recent handling. In vivo