Computational joint models are versatile tools that offer the ability to evaluate joint mechanics under a variety of loading conditions and states that would be infeasible to evaluate experimentally. The fidelity of a computational knee model’s predicted mechanics has been shown to be sensitive to the assigned ligament properties. Ligaments are generally represented as either a bundle of nonlinear springs or a solid continuum;​ however, regardless of the ligament representation, the model’s performance is particularly sensitive to ligament prestrain.

The goal of this dissertation was to develop a workflow to calibrate ligament properties using a novel rigid body knee model (kinetic-WraptMor) and utilizing the calibrated model to define mechanically consistent spring-based and continuum finite element (FE) ligament models. The value of this workflow is that it utilizes a computationally efficient model to estimate specimen-specific ligament properties and generates “indirectly” calibrated spring-based and continuum FE ligament models. Different ligament representations were considered mechanically consistent when they imparted similar kinetics when simulating the same joint position.

The indirectly calibrated spring-based models were generated by applying pre-strains estimated from calibrating the kinetic-WraptMor model to a corresponding forward dynamics FE knee model. Simulations of experimental tests showed that the indirectly calibrated forward dynamics model was generally able to predict specimen-specific kinematics with similar accuracy to previous studies. The forward dynamics model has increased utility compared to the kinetic-WraptMor model because it can be utilized in load controlled simulations to predict commonly measured metrics, such as joint kinematics and articular contact metrics.

The continuum ligament models were calibrated by using kinetics defined from the kinetic-WraptMor model as inputs for an inverse FE analysis, and the results defined the calibrated continuum ligament model’s reference configuration. Displacement controlled simulations showed that the calibrated continuum ligament models were generally able to reproduce the trends in the spring-based model’s kinetics. This work served as a proof of concept for utilizing calibrated spring-based ligament representations to indirectly calibrate continuum ligament models. The continuum ligament models offer increased utility over the kinetic-WraptMor model because they can be utilized to predict three dimensional stress, which is more appropriate for evaluating ligament injury