Investigating contact stresses on articular surfaces by 3D rigid links

The main purpose of this paper is to compare the efficiency and the difference of the three-dimensional (3D) stress distribution on articular surfaces between the traditional finite element method and the rigid-link finite element method (RFEM). In the RFEM, a 3D finite element (FE) (8-20-node solid elements) including the rigid link effect was developed for static and dynamic analyses. This element incorporating a 3D contact element can efficiently determine the contact pressure distribution on articular surfaces and the stress distribution within the cartilage. Numerical results in this paper indicate that both methods yield similar results. The major advantage of this RFEM is that only the soft cartilage requires FE mesh, while the hard bone structure can be modeled as a rigid body due to its relatively rigid nature. Since much fewer nodes and elements are required in the FE mesh, fast computing speed can be achieved.