The effect of patellar groove on mechanical performance of femoral component

The amount of total knee arthroplasty (TKA) procedures in global is expected to rise four times by 2030 due to the ageing global population. One of the reasons for revision surgery in TKA is due to patello-femoral complications. Conformity between trochlea and femoral condyles of femoral component implant to normal anatomy knee should be observed since it affects how mechanical stress is distributed along the knee flexion. Inappropriate femoral component implant geometry and size can cause overstuffing of the patellofemoral joint during TKA. Overstuffing of patellofemoral section is related to anterior knee pain and aseptic loosening of implant. Here, we extend the study of patellofemoral aspect of TKA by studying the effect of patellar groove features of femoral component acting as trochlea to mechanical performance of femoral component during static loading by computational model and finite element method (FEM). TKA’s femoral component are designed based on commercial products and knee morphometry of adult Indonesian. Each design has similar geometrical features and size except for the area that represents the patellar groove on natural anatomic knee. One design has a flat surface on the patellar groove, while the other has curvatures on the patellar groove. Based on von Mises stress and volumetric strain, the two designs have similar mechanical performance to bear static load. Comparative study on cortical bone vs Ti-6Al-4V shows that the proposed implant material is representative to replace natural bone in terms of mechanical performance.