Prediction of patellofemoral joint kinematics and contact through co-simulation of rigid body dynamics and nonlinear finite element analysis

Abstract

Joint-level rigid body dynamics simulations, when coupled with tissue-level finite element analyses, can simultaneously provide movement and tissue deformation metrics to understand mechanical interactions within the joint on a multi-scale level. In this study, a co-simulation workflow of a joint-level rigid body model that predicts the relative motion as a function of the non-linear cartilage response predicted by a non-linear implicit finite element solver is presented. Predictions are compared to in-vitro measurements (The Open Knee(s) project) in terms of the mean error and level-of-agreement: pressure_error = 0.46 MPa (level-of-agreement, −0.23 – 1.1 MPa); area_error = −89 mm² (level-of-agreement, −280 – 98 mm²) and contact force_error = 93 N (level-of-agreement, 7.8 – 180 N). The automated co-simulation control algorithm enables multiscale coupling between joint and tissue-level models with real-time two-way communication as opposed to the traditional feed-forward approach of multi-scale models.

Keywords:

• Co-simulation
• patellofemoral
• rigid body
• multiscale
• nonlinear finite element

Acknowledgement

The Open Knee(s) project is thanked for making the experimental data used in this study available to the community.

Disclosure statement

No potential conflict of interest reported by the author(s).

Appendix

 

Notes

1 (https://simtk.org/plugins/moinmoin/openknee/oks001, 2018)

Additional information

Funding

Contributions of Jacobus Müller were supported by the Oppenheimer Memorial Trust and the HB and MJ Thom Trust. Contributions of Ahmet Erdemir were partly supported by the National Institute of General Medical Sciences (NIGMS), National Institutes of Health (NIH) (R01GM104139), the funding source of Open Knee(s) project.