Abstract
The knee joint is a very complex joint stabilized by two opposing sets of ligaments. A mathematical model of the knee with an appropriate level of complexity and accuracy is needed for valid and useful static or dynamic analysis. Existing work has focused on the knee as either a one degree of freedom pin joint (simple) or based on a more complex sliding motion of two surfaces (complex). In this work, MATLAB and Working Model (c) were used to design three intermediate level models describing the motion of the knee assuming only movement in the sagittal plane by changing the shape of the tibial plateau (flat, concave, or convex). From these, it was determined that the simple flat model, while not perfect, most appropriately modeled the knee joint.