Material properties of the heel fat pad across strain rates.
biomechanical · Level V
Where this comes from
- Record sourced from PubMed, PMID 27643676.
- Also identified by DOI 10.1016/j.jmbbm.2016.09.003 and PMC identifier 5161234.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The complex structural and material behaviour of the human heel fat pad determines the transmission of plantar loading to the lower limb across a wide range of loading scenarios; from locomotion to injurious incidents. The aim of this study was to quantify the hyper-viscoelastic material properties of the human heel fat pad across strains and strain rates. An inverse finite element (FE) optimisation algorithm was developed and used, in conjunction with quasi-static and dynamic tests performed to five cadaveric heel specimens, to derive specimen-specific and mean hyper-viscoelastic material models able to predict accurately the response of the tissue at compressive loading of strain rates up to 150s<sup>-1</sup>. The mean behaviour was expressed by the quasi-linear viscoelastic (QLV) material formulation, combining the Yeoh material model (C<sub>10</sub>=0.1MPa, C<sub>30</sub>=7MPa, K=2GPa) and Prony׳s terms (A<sub>1</sub>=0.06, A<sub>2</sub>=0.77, A<sub>3</sub>=0.02 for τ<sub>1</sub>=1ms, τ<sub>2</sub>=10ms, τ<sub>3</sub>=10s). These new data help to understand better the functional anatomy and pathophysiology of the foot and ankle, develop biomimetic materials for tissue reconstruction, design of shoe, insole, and foot and ankle orthoses, and improve the predictive ability of computational models of the foot and ankle used to simulate daily activities or predict injuries at high rate injurious incidents such as road traffic accidents and underbody blast.
Medical subject headings
- Adipose Tissue
- Heel