This presentation was made at CAASE18, The Conference on Advancing Analysis & Simulation in Engineering. CAASE18 brought together the leading visionaries, developers, and practitioners of CAE-related technologies in an open forum, to share experiences, discuss relevant trends, discover common themes, and explore future issues.

Resource Abstract

Manufacturers and regulatory agencies share a common goal of having safe and effective total knee arthroplasty (TKA) products available in the global marketplace. Several methods of testing TKA designs, inclusive of virtual computational models and physical laboratory wear test simulations, are employed to predict polymer tibial insert damage patterns. However, the latter is criticized for poor clinical correlation, long testing times, large expense and the difficulty in providing meaningful comparisons with other clinically successful designs.

Thus, virtual testing is finding an increasing role in defining TKA performance in clinical orthopedics. The virtual test methods described in this presentation are able to discern differences in performance between TKA designs, are faster and less expensive than physical methods, solve the contemporary problem of obtaining predicate designs for comparison and have been accepted by the US Food and Drug Administration as evidence of safety and effectiveness for pre-clinical product testing.

Computational estimates of short and long term clinical performance of a large variety of artificial knee designs are obtained using non linear finite element and multibody kinematic modeling tools, both employing sophisticated component contact algorithms. Measures of component longevity (polymer bearing component stress and dynamic wear paths) and patient satisfaction (range of knee flexion and joint stability) are directly comparable between new designs and those with successful clinical histories.

Computational finite element and kinematic modeling tools offer an effective alternative for predicting the in-vivo performance of TKA designs. The computational results compare favorably to industry and regulatory agency accepted evidences of contact areas and stress measurements, laboratory wear simulation, clinical range of motion and worn component retrievals. These validated tools are also most useful in the product development stage to vet design concepts computationally, prior to the time and expense required for prototype production and subsequent physical laboratory testing.

A large database of results is publicly available at http://orl-inc.com.