Annals of Biomedical Engineering

, Volume 44, Issue 9, pp 2805–2816 | Cite as

Development and Validation of a High Anatomical Fidelity FE Model for the Buttock and Thigh of a Seated Individual

  • Rami M. A. Al-DiriniEmail author
  • Matthew P. Reed
  • Jingwen Hu
  • Dominic Thewlis


Current practices for designing new cushions for seats depend on superficial measurements, such as pressure mapping, which do not provide sufficient information about the condition of sub-dermal tissues. Finite element (FE) modelling offers a unique alternative to integrate assessment of sub-dermal tissue condition into seat/cushion design and development processes. However, the development and validation of such FE models for seated humans requires accurate representation of the anatomy and material properties, which remain challenges that are yet to be addressed. This paper presents the development and validation of a detailed 3D FE model with high anatomical fidelity of the buttock and thigh, for a specific seated subject. The developed model consisted of 28 muscles, the pelvis, sacrum, femur, and one layer of inter-muscular fat, subcutaneous fat and skin. Validation against in vivo measurements from MRI data confirmed that the FE model can simulate the deformation of soft tissues under sitting loads with an accuracy of (mean ± SD) 4.7 ± 4.4 mm. Simulation results showed that the maximum strains (compressive, shear and von-Mises) on muscles (41, 110, 79%) were higher than fat tissues (21, 62, 41%). The muscles that experienced the highest mechanical loads were the gluteus maximus, adductor magnus and muscles in the posterior aspect of the thighs (biceps femoris, semitendinosus and semimembranosus muscles). The developed FE model contributes to the progression towards bio-fidelity in modelling the human body in seated postures by providing insight into the distribution of stresses/strains in individual muscles and inter-muscular fat in the buttock and thigh of seated individuals. Industrial applications for the developed FE model include improving the design of office and household furniture, automotive and airplane seats and wheelchairs as well as customisation and assessment of sporting and medical equipment to meet individual requirements.


Sub-dermal strains Soft-tissue deformation Sitting MRI FE simulation 



AutoCRC and the Maurice de Rohan Scholarship funded this research.


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Copyright information

© Biomedical Engineering Society 2016

Authors and Affiliations

  1. 1.School of Computer Science, Engineering and MathematicsFlinders UniversityAdelaideAustralia
  2. 2.University of Michigan Transportation Research InstituteUniversity of MichiganAnn ArborUSA
  3. 3.Division of Health Sciences, Sansom Institute for Health ResearchUniversity of South AustraliaAdelaideAustralia

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