Finite element analysis of undermining of pressure ulcer with a simple cylinder model

Abstract

With pressure sores, surface damage indicates that subcutaneous fat tissue necrosis has occurred. We hypothesized that formation of necrosis under a pressure sore changes the stress distribution, which in turn affects further extension of the necrosis. In the present study, two-dimensional finite element models were used to perform analysis under different undermining size conditions. Greater stress concentration was observed in the larger undermining model. This may be the reason that, in clinical situations, a large area of undermining necrosis is sometimes observed under the skin of sores with a small area of damage.