The objective of this research was to assess the suitability of a commercial dynamic finite element (FE) package (LS-DYNA) to simulate the mechanics of a Total Knee Replacement (TKR) in mechanical testing and functional loading environments.

Investigations were performed to characterize contact algorithms and to establish parameter values in LSDYNA. Convergence tests were performed for static and dynamic configurations. A study was performed to determine an appropriate coefficient of friction value.

A commercial TKR testing machine (Force 5) was used to conduct experimental tests on the components. An FE model of the Force 5 was developed. Tibial reaction loads, recorded experimentally, were accurately reproduced by the FE model. An application was developed to generate control waveforms for the Force 5 using the simulations. Computational wear models, based on the simulations, were used to predict TKR wear during long term testing.

A mechanical knee analog was constructed to simulate an open chain extension movement. The device included a tibia, patella, a quadriceps mechanism and tension springs as collateral ligaments. Kinematic and loading data were collected during experimental trials and a dynamic FE model was used to predict the experimental outputs.

An apparatus was developed that simulated a Closed-Chain Extension (CCE) movement, with 6 degreeof-freedom kinematics, under quadriceps loading using cadaveric knees. Experimental trials were performed on four specimens before and after undergoing a TKR procedure. The Q-angle was varied and a medial ligament release was performed. Kinematic data, quadriceps tension and loads acting on the tibia were collected.

Specimen-specific FE models were created. The experimental CCE trials were simulated for all specimens. The effect of Q-angle and medial release were examined using one of the specimen models. Kinematic and loading trends were predicted well, while absolute values were offset. The kinematic and loading changes due to the different Q-angle and the medial release were predicted well.

The dynamic FE modelling framework proved to be a capable tool for mechanical testing environments and several practical applications were developed. The in vitro modelling was a preliminary step towards predictive simulations of functional knee mechanics and a base for future work.