2022, Vol. 26 ›› Issue (9): 1357-1361
Finite element analysis of biomechanical changes in the osteoarthritis knee joint in different gait flexion angles
Patients with mild knee osteoarthritis are prone to induce pain and aggravation of arthritis during daily gait walking. At present, the changes in the biomechanical behavior of the internal knee joints of such patients under the gait flexion angle are not very clear. There are few reports in the literature.
Based on the proven finite element model of the mild osteoarthritis knee joint, according to the change of gait cycle and knee flexion angle, to simulate the knee flexion behavior at four angles of 0°, 10°, 20°, and 30°, and to study the stress distribution characteristics and contact area changes of femoral cartilage, tibial cartilage, and meniscus.
The material properties of the finite element model of the mild osteoarthritis knee joint were defined. The boundary conditions and the axial load were determined under different knee flexion angles. By analyzing the Mises stress, Tresca stress, and contact area of the non-bone tissue in the tibiofemoral joint, the biomechanical behavior changes inside the knee joint were studied.
The results of finite element analysis showed that as the knee flexion angle increased, the peak Mises stress and the peak Tresca stress on the meniscus, femoral cartilage, and tibial cartilage showed a relatively increasing trend. The total contact area of the tibiofemoral joint showed a decreasing trend, and the medial meniscus subluxation caused the lateral peak to be larger than the medial peak. Meanwhile, the contact area of the medial compartment decreased and the contact area of the lateral compartment increased. When the knee flexion angle reached 20° and 30°, the peak of Mises stress and the peak of Tresca stress appeared. Results showed that when the knee flexion angle of the mild osteoarthritis knee joint changed, the internal stress and contact area change characteristics changed because of the medial meniscus subluxation. The medial contact area decreased; the peak stress increased; and the lateral contact area increased. The peak stress increased and the increase was greater than the inside. The breakdown of the internal load balance of the joint may increase the risk of articular cartilage degeneration and promote the aggravation of knee osteoarthritis.
knee, osteoarthritis, finite element analysis, knee flexion, gait cycle, biomechanical behavior