In pedestrian safety research, the definition of an injury criterion for the knee joint should provide issues to future regulation procedures. Also, do the existing injury criteria (based on knee lateral shearing levels and flexion levels for sub-segment testing) remain efficient for full scale tests? Is the impact location on the leg influencing injury mechanisms and injury criteria assumptions? Lastly, what are the potential consequences of these differences to the pelvis component during the first phase of impact? The LLMS lower limb model coupled to a hybrid 3 was used to investigate these questions. This work was based on pedestrian full scale experiments performed in the Laboratory and a sensitivity analysis regarding various impact positions. The results obtained for this car geometry showed that injury mechanisms (i. e. the proportion of shearing and lateral flexion) for the knee joint and the pelvis are directly related to the impact position. Lastly they lead to improve existing injury criteria by adding combination of two injury modes.