Effects of femoral prosthetic materials on artificial knee arthroplasty performance / 中国组织工程研究

ABSTRACT

BACKGROUND: Aseptic loosening of the femoral prosthesis is one of the important issues affecting the life of knee joint replacement. Particles from tibial polyethylene component wear and stress shielding are the main causes of this loosening, which are all related to the femoral prosthesis materials. OBJECTIVE: To study the effects of femoral prosthesis materials on the stress of the distal femur of the knee joint and the contact pressure on the polyethylene component by finite element method. METHODS: Knee arthroplasty models with four materials, titanium alloy, cobalt-chromium alloy, titanium-hydroxyapatite functional gradient biomaterial (FGBM I), titanium-bioactive glass functional gradient biomaterial (FGBM II), were established; the prosthesis was endowed with different material properties in the Abaqus finite element software. The stress distribution of the important vulnerable path in the femur and the changes of contact pressure on the polyethylene component under different materials were studied. RESULTS AND CONCLUSION: (1) Compared with the currently used titanium alloy and cobalt-chromium alloy, functional gradient biomaterials could significantly increase the stress at the femoral-prosthetic interface and the stress in the pathway of an important vulnerable region of the femur. In those materials, FGBM I increased most significantly. (2) Maximum stress of FGBM I and FGBM II prostheses on polyethylene insert was 20.41% and 19.98% lower than cobalt-chromium alloy, 20.07% and 19.63% lower than titanium alloy. (3) The results showed that functionally gradient biomaterials could produce higher stress at the distal end of the femur and lower contact pressure on the polyethylene insert, reducing the wear and stress shield on polyethylene insert, and FGBM I has significant effects.