Biomechanical Effect of Various Tibial Bearing Materials in Uni-Compartmental Knee Arthroplasty Using Finite Element Analysis

This paper aimed to evaluate the biomechanical effects of tibial bearing materials, from ultra-high-molecular-weight polyethylene (UHMWPE) to poly-ether-ether-ketone (PEEK) and carbon-fiber-reinforced poly-ether-ether-ketone (CFR-PEEK). The studies were conducted based on a validated finite element model. The geometry of the intact knee model was developed from computed tomography and magnetic resonance imaging of the left knee joint of a 37-year-old healthy male volunteer. Three different loading conditions, related to the loads applied in the experimental research, were applied to this study for model predictions and validation. The contact stress in the other compartments was under normal walking conditions. Also, stresses on five regions of the tibia bone were analyzed under normal walking conditions. The lowest contact stress between the lateral meniscus and tibial cartilage was achieved in the order of the use of CFR-PEEK, PEEK, and UHMWPE tibial bearings. Moreover, CFR-PEEK and PEEK tibial bearings indicated lower and greater stresses on cortical and trabecular bones, respectively, compared to the UHMWPE tibial bearing. These results show that CFR-PEEK can be used as a tibial bearing material as an alternative to UHMWPE, and such a change in the material may be a good method for reducing potential anteromedial pain.