Computational development of a polyethylene wear model for the articular and backside surfaces in modular total knee replacements

A computational model to predict polyethylene wear in modular total knee replacements was developed. The results from knee simulator wear tests were implemented with finite element simulations to identify the wear factors of Archard's wear law. The calculated wear factor for the articular and backside surface was 1.03±0.22×10−7 mm3/Nm and 2.43±0.52×10−10 mm3/Nm, respectively. The difference in wear factors was attributed to differences in wear mode and wear mechanisms between the articular (mainly two-body rolling/sliding wear mode with an abrasive/adhesive wear mechanism) and the backside surfaces (mainly fretting wear mode with an adhesive wear mechanism).

► A wear model was developed for the articular and backside surfaces of a TKR.
► Wear factors were identified using knee simulator and finite element results.
► Wear factors vary over 0–3 million cycle test interval.
► Average relevant wear factor for the articular surface: 1.03E−7 mm3/Nm.
► Average relevant wear factor for the backside surface: 2.43E-10 mm3/Nm.