(LR-040) The Impact of Dressing Pad Design For Pressure Injury Prevention: A Finite Element Study

Ciara Cassidy, BEng – Engineer, Science and Research Group, Research and Development, Smith + Nephew; Michael Laughton, PhD – Department an Engineering – University of Hull; Sarah Crossland, PhD – Lecturer in Medical Engineering, School of Engineering, University of Hull; Euan Motion, BSc – Staff Scientist, Science and Research Group, Research and Development, Smith + Nephew; Runi Brownhill, PhD – Director, Science and Research Group, Research and Development, Smith + Nephew; Louise France, PhD – Director of Learning and Teaching, Department an Engineering, University of Hull

Introduction:

Pressure ulcers pose significant healthcare challenges, causing morbidity, prolonged hospitalisation, and high costs. Prophylactic dressings can mitigate mechanical forces at vulnerable sites, but performance depends on material properties and interlayer mechanics.

These studies compared an unbonded multilayer dressing (UD*), a bonded dressing (BD^†), and a single-layer hydrogel dressing (HD^‡) regarding mechanical force dissipation.

Methods:

This work brings together multiple finite element modelling studies. The following parameters were assigned to the relevant materials or dressings: compressive elastic moduli, Poisson’s ratio, and interlayer friction where appropriate. UD* layers: mask, superabsorbent polymer (SAP), and foam were assessed individually; BD† and HD^‡ were tested in bulk. Data informed a finite element (FE) heel model incorporating skin, adipose, and bone under compression and shear.

Results:

FE simulations showed UD* reduced peak adipose strain by 19.9% versus undressed heel, 3.9% for BD^†, and 2.2% for HD^‡. In high-strain regions ( >0.7), UD* achieved reductions of 67.1% versus no dressing, BD^† achieved 26.5%, and HD^‡ achieved 8.8%. Interlayer sliding in UD* dissipated shear more effectively than bonded or single-layer designs, promoting strain dissipation.

Discussion:

Layer-specific mechanics and interfacial dynamics influence dressing efficacy. UD*’s unbonded architecture provided superior strain reduction compared to bonded and single-layer dressings. This experimental–computational approach offers a framework for optimising next-generation prophylactic dressings.