Analysis and Assessment through Mechanical Static Compression Tests of Damping Capacity in a Series of Orthosis Plantar Materials Used as Supports

Abstract

High plantar pressure is the cause of multiple types of foot injuries and one of the main reasons for patient visits in podiatry and traumatology. Therefore, there is a need to acquire specific tools to address such injuries. The aim of this study was to determine the absorption capacity of selected materials applied as plantar supports and their response to pressure. The study had a cross-sectional design. A total of 21 materials were chosen and different material families were assessed, including ethylene-vinyl acetate, polyurethane foams, and polyethylene foams. Static compression tests were performed to analyze each material. The system is ideally suited for lower-force applications, small components, biomedical applications, and lower-strength materials. Damping was determined using mathematical calculations performed on the study data. It was found that materials with a low Shore A, or soft materials, exhibited worse absorption capacity than harder materials. Ethyl-vinyl acetates had good absorption capacity, polyurethane foams had a poor absorption capacity, and soft materials provided better adaption to impact. The results suggested that damping is not determined by the hardness of the material, and materials within the same family exhibit different damping capabilities.

A Wearable Insole System to Measure Plantar Pressure and Shear for People with Diabetes

“…The sensorised insole ( Figure 1 b) consists of three layers of material, i.e., Ethylene-vinyl acetate or EVA (nora ® Lunacell, nora systems GmbH, Weinheim, Germany), synthetic leather (Yampi, A. Algeo Ltd., Liverpool, UK) and Lycra. These are the typical materials used for constructing a layered orthotic insole, as they demonstrate suitability for appropriate biocompatibility, durability and shock absorption against industry standards [ 28 , 29 ]. Sensors were embedded in the middle EVA layer.…”