Subject-specific finite element modelling of the human foot complex during walking: sensitivity analysis of material properties, boundary and loading conditions

• Published in: Biomechanics and modeling in mechanobiology Vol. 17; no. 2; pp. 559 - 576
• Main Authors: Akrami, Mohammad, Qian, Zhihui, Zou, Zhemin, Howard, David, Nester, Chris J, Ren, Lei
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.04.2018; Springer Nature B.V
• Subjects: Adult; Ankle; Biological and Medical Physics; Biomechanical Phenomena; Biomechanics; Biomedical Engineering and Bioengineering; Biophysics; Boundary conditions; Computer Simulation; Engineering; Error detection; Feet; Finite Element Analysis; Finite element method; Foot - physiology; Gait; Humans; Imaging, Three-Dimensional; Magnetic resonance imaging; Male; Mathematical models; Modelling; Models, Biological; Multibody systems; Muscles; Original Paper; Pressure; Reproducibility of Results; Sensitivity analysis; Theoretical and Applied Mechanics; Three dimensional models; Walking; Walking - physiology; Weight-Bearing; Biomechanics; Locomotion; Human foot; Finite element analysis
• ISSN: 1617-7959; 1617-7940; 1617-7940
• DOI: 10.1007/s10237-017-0978-3

The objective of this study was to develop and validate a subject-specific framework for modelling the human foot. This was achieved by integrating medical image-based finite element modelling, individualised multi-body musculoskeletal modelling and 3D gait measurements. A 3D ankle–foot finite element model comprising all major foot structures was constructed based on MRI of one individual. A multi-body musculoskeletal model and 3D gait measurements for the same subject were used to define loading and boundary conditions. Sensitivity analyses were used to investigate the effects of key modelling parameters on model predictions. Prediction errors of average and peak plantar pressures were below 10% in all ten plantar regions at five key gait events with only one exception (lateral heel, in early stance, error of 14.44%). The sensitivity analyses results suggest that predictions of peak plantar pressures are moderately sensitive to material properties, ground reaction forces and muscle forces, and significantly sensitive to foot orientation. The maximum region-specific percentage change ratios (peak stress percentage change over parameter percentage change) were 1.935–2.258 for ground reaction forces, 1.528–2.727 for plantar flexor muscles and 4.84–11.37 for foot orientations. This strongly suggests that loading and boundary conditions need to be very carefully defined based on personalised measurement data.