Fig. 1

Overview of the methodology employed to assess internal loading, by combining measurements and musculoskeletal modelling. Gait analyses were performed during walking and stair negotiation, with simultaneous measurement of the in vivo tibio-femoral forces and surface EMG of the main muscles. Patient specific skeletal anatomy from CT was used to adapt reference muscles geometries, and then combined with functionally determined joint centres/axes to obtain the skeletal kinematics. The resulting musculoskeletal models were constrained to match the in vivo forces and verified using the EMG measurements