Stress Distribution in Femoral Stems for Revision Total Knee Arthroplasty with Three Different Materials: A Comparative Finite Element Study

Knee replacement surgery is a common treatment for patients with end-stage knee arthrosis. Unfortunately, the age of patients suffering from this condition and requiring knee joint replacement is decreasing, leading to an increase in the need for revision surgeries. Therefore, using suitable prostheses can increase the durability of joint replacement and the success of this procedure. For this purpose, in this research, three materials, Co-Cr, Ti6AI4V, and FGM, were examined by the finite element method. An accurate three-dimensional model of the distal part of the femur bone was developed, and after designing the stem, its volume was subtracted from the bone, and the final assembly model and material properties were assigned to it. The models were subjected to jogging (6Km/h) and walking loading conditions. The findings of this research showed that in both loading conditions, the Co-Cr stem was subjected to stress more than twice the stress applied to the other two stems. Also, jogging applies more stress to the stem-bone construct than walking. According to the results of this research, it can be said that the use of FGM and Ti6A14V stems is preferable, although the construction costs should also be considered. In addition, examining more active movements can be influential in determining movement limitations after revision surgery.