Table of Contents
Journal of Medical Engineering
Volume 2013, Article ID 891759, 11 pages
Research Article

Using Design of Experiments Methods for Assessing Peak Contact Pressure to Material Properties of Soft Tissue in Human Knee

1Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, 43400 Selangor, Malaysia
2Faculty of Engineering, Semnan Branch, Islamic Azad University, Semnan, Iran
3Institute of Advanced Technology, ITMA, Universiti Putra Malaysia, Selangor, Malaysia
4Department of Orthopedic Surgery, Faculty of Medicine & Health Science, Universiti Putra Malaysia, Selangor, Malaysia
5Department of Mechanical Engineering, K.N. Toosi University of Technology, Tehran, Iran

Received 24 February 2013; Revised 9 June 2013; Accepted 15 July 2013

Academic Editor: Kaisar Alam

Copyright © 2013 Marjan Bahraminasab et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Contact pressure in the knee joint is a key element in the mechanisms of knee pain and osteoarthritis. Assessing the contact pressure in tibiofemoral joint is a challenging mechanical problem due to uncertainty in material properties. In this study, a sensitivity analysis of tibiofemoral peak contact pressure to the material properties of the soft tissue was carried out through fractional factorial and Box-Behnken designs. The cartilage was modeled as linear elastic material, and in addition to its elastic modulus, interaction effects of soft tissue material properties were added compared to previous research. The results indicated that elastic modulus of the cartilage is the most effective factor. Interaction effects of axial/radial modulus with elastic modulus of cartilage, circumferential and axial/radial moduli of meniscus were other influential factors. Furthermore this study showed how design of experiment methods can help designers to reduce the number of finite element analyses and to better interpret the results.