2008 Volume 74 Issue 737 Pages 121-127
The objective of this study is to analyze contact conditions of the posterior stabilizer (PS) type knee prosthesis at level walking and ascending stairs using a 3D mathematical model. Our 3D model made it possible to reproduce comprehensive knee motion, since it included not only the tibiofemoral joint but also the patellofemoral joint. In the model, the forces of major muscles, ligaments and tendons were all taken into account. If we input the data of muscle forces, floor reaction forces and knee flexion angles into the model, then we could determine such variables as the relative positions between the two components, contact points and stresses between the articulating surfaces and valusvalgus and internal-external rotation angles between the tibio-femoral components. Simulation was conducted and the following results were introduced. On the patellofemoral joint, the maximum contact stress at ascending stairs was 2 times higher that that at level walking. On the tibiofemoral joint, the maximum contact stress at ascending stairs was 1.7 times higher that that at level walking. The post/cam contact occurred only at ascending stairs and the contact stress reached as much as 67.1 MPa.
Transactions of the Society of Mechanical Engineers
Transactions of the Japan Society of Mechanical Engineers
Transactions of the Japan Society of Mechanical Engineers Series A
Transactions of the Japan Society of Mechanical Engineers Series B
TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C
TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B
TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A
