Kinematics of the Lower Limb and Prediction of Tibiofemoral Force During the Stance Phase

Abstract

The musculoskeletal model has been received great attention due to the ability to clinical treatment and disease analysis, animation, and humanoid robot control. Different software is used to perform that. However, most of them using cadaver data which may lead to unrealistic results. The paper introduces a simple model not only to find the kinematics of the lower limb but also to predict the tibiofemoral force. The markers trajectory for a subject is used to get the kinematics of the lower limb based on defining the anatomical frame at the joints and tracking cluster frames at each segment. Global optimization is used to overcome soft tissue artefacts (STA) based on the least square error between the measured marker position and its model. The dynamics of the lower is analyzed where the external force and moment affecting the knee are calculated and static optimization is used to predict the tibiofemoral force for the medial and lateral tibia compartments. The results are compared to in vivo data of the same subject to guarantee validity. The 1st and the 2nd peak for the medial tibia compartment are 1.33 ±0.17 BW, and 1.34± 0.08 BW whereas for the lateral tibia compartment are 0.125±0.04 BW, and 0.92±0.08 BW respectively. The model can be used to predict the tibiofemoral force and so controlling the human motion using a knee brace or exoskeletons.