The purpose of this study is to investigate the effects of anterior bundle of ACL (aACL), anterior portion of PCL (aPCL), anterior and deep portions of MCL (aMCL, dMCL) and the tibio-femoral articular contacts on to passive knee motion. A three-dimensional simplistic anatomical dynamic model, based on the literature was used as a reference. This reference model attaches the bundles of the ligaments on medial and the lateral spherical condyles of the femur and tibial plateau giving us a representation close enough to a normal natural tibio-femoral joint, but does not allow to study abnormalities of the knee kinematics due to the assumptions of the femur shape. The proposed three-dimensional dynamic tibio-femoral model, however includes the isometric fascicles, aACL, aPCL, aMCL, dMCL, and irregularly shaped medial-lateral contact surfaces. The approach taken in this model is capable of ligament and bone surface modifications that will enable us to analyze bone shape and ligament related abnormalities of knee kinematics.