Dynamic Study of Insole Materials Simulating Real Loads

Abstract

A new methodology of biomechanical analysis of materials for shoe inserts is presented. This methodology is based on the determination of the loads applied to the materials in real situations and its simulation by means of a dynamic testing machine. Both the rigidity and the energy-absorbing characteristics of the materials are investigated as a function of frequency. This methodology is applied to the study of several commercially available viscoelastic materials intended for shoe inserts in the treatment and prevention of degenerative joint diseases. The influence of thickness is investigated as well as the frequency-dependent behavior of the materials studied. Significant differences between materials and different behavior as a function of thickness and frequency were found. Poron materials were found to have the lowest rigidity, good for adequate pressure distribution, while Noene showed the highest energy absorption. A careful selection of the thickness of Sorbothane was found to be necessary for avoiding flattening of the material.

3D printing of functional anatomical insoles

“…Properties such as hardness, tensile strength, rigidity, flexibility and permeability directly depend on the constituent material and have been the object of some studies [11,12]. One of the most commonly employed materials over recent years is ethylene-vinyl acetate or EVA, which is a thermoset polymer supplied in sheet form in different thicknesses and sizes.…”

Local plantar pressure relief in therapeutic footwear: design guidelines from finite element models

“…Pressure at the region of interest (peak pressure location simulated by the control model) and pressure at the proximal edge of the plug were also extracted. Three materials commonly used in prosthetics (Sanders et al, 1998) and therapeutic footwear (Leber and Evanski, 1986;Garcia et al, 1994;Ashry et al, 1997) were chosen for the plugs: Microcell Puff Lite, Plastazote Medium and Poron (Acor, Inc., Cleveland, OH). These materials are all softer than Microcell Puff, the midsole material used for simulations (Table 1 and Fig.…”

“…Design and selection of a suitable shoe for a patient at high risk of ulceration or a patient in pain is mostly based on the experience and intuition of the physician and footwear provider rather than on scientifically based design principles . There are a number of experimental studies on footwear (Leber and Evanski, 1986;Garcia et al, 1994;Ashry et al, 1997) that have attempted to provide insight, but generalization of results is often not possible due to the wide range of patient characteristics and multiple possible design variables. As an alternative, a limited number of studies have proposed modeling approaches.…”

Virtual Shoe Test Bed: A Computer-Aided Engineering Tool for Supporting Shoe Design

“…In lab environment this is simulated as a drop test carried out with physical prototypes. The vertical displacement and the energy dissipation are measured to evaluate the shock absorption property of the shoe [7]. In VSTB, shock absorption is simulated using the parts of the shoe which correspond to sole, mounting insole and insole.…”