Effect of prosthetic socks on the frictional properties of residual limb skin

Abstract

Abstract The friction between stump and prosthetic socket can cause friction injuries to the stump skin. Therefore, most amputees usually wear prosthetic socks to protect the stump skin. In this study, in vivo tribological behaviors, mechanical irritations and comfort sensations of stump skin against different prosthetic socks were investigated using a UMT-II tribometer under the simulated prosthetic socket wearing conditions. The worn morphologies of impression replicas instead of the real skin specimens were examined by scanning electron microscopy. The visual scoring system was used to evaluate primary skin irritation manifested as erythema and edema. Four descriptors were identified to qualitatively characterize skin comfort sensations. Results showed that the tribological behaviors, mechanical irritations and comfort sensations of stump skin were closely associated with the weave parameters, surface features and material composition of socks fabrics. The friction coefficients were higher when the skin slid against wool and nylon socks due to their coarse knitting weave surfaces and hard protruding textile fibers, causing clear microscopic trauma to the skin, accompanied by skin irritations and discomfort. When the skin slid against cotton and silk socks, lower friction coefficients, less irritations and discomfort sensations were observed because of their soft and smooth surface textile features.