Mechanical Property Analysis Based On The Modeling Human Knee Articular

Knee as the body's most complex, the large joint in the hip and ankle, and is the hub of lower extremity, and its importance is self-evident. The disease on the knee becomes more and more people's attentions, the scholars have more and more in-depth study on the knee. In recent years, knee anatomy and the corresponding biomechanical properties become the focus of research. The biomechanical environment of the knee joint have an important effect on the injuries of knee joint and arthritis of lesions, therefore, the biomechanical analysis of knee joint not only can help us to understand the mechanism of knee trauma, but also can provide scientific guidance and plans for the diagnosis and rehabilitation after surgical. Recently, many scientific researchers are devoting to explore the biomechanical properties of knee joint, from the physical model at the beginning change to the mathematical model at current. Many scholars have also proposed different static and dynamic model of the knee, but in most of these models, the knee bones are simply assumed to be rigid body structure and the model does not include the knee joint meniscus,ligaments,cartilage and other auxiliary structure tibia femur, and these structures plays an irreplaceable role in the knee of the pump power and force, which have a major influence on the calculation results. Because of the complexity of knee joint anatomical structure and movement, the researchers still have difficulty to make an accurate description on the mechanical properties and motion of the knee joint.Cartilage plays a very important role in the movement and force of the knee joint, and can bear load,cushion pressure and absorb shocks. According to the experimental data of knee joint cartilage and phenomena, assuming that the cartilage is homogeneous and isotropic nonlinear viscoelastic, then we derive the nonlinear constitutive equation of the cartilage and construct the corresponding finite element model to simulate the experiment. Eventually, we obtain that our assumption is reasonable.Through simulate to the contact mechanical characteristics of the knee joint, the data show that the load is mainly withstand by the medial tibial plateau, the contact area of the inner cartilage covers 65% of the total contact area and the contact force of the inner cartilage covers 75% of the total contact force. And the maximum stress also appears in the inside of the cartilage surface. The above data demonstrate that the load is mainly transferred by the medial meniscus and medial cartilage while loading the knee joint, the medial cartilage and medial meniscus are the most vulnerable of the site. When only the degree of UR1 is imposed on the tibia, namely the imposition of knee extension rotational restraint, so that the distribution of the calculated contact area and contact force is more reasonable, and this boundary conditions and constrains are also consistent with the physical movement of the knee.