Pedestrians sustain injuries relative to their legs very frequently. These injuries are related to contact with vehicle front ends and may have long term consequences. A deformable instrumented mechanical leg has been designed for protection the risk of pedestrian leg injuries based upon injury tolerance parameters. This paper will discuss the biofidelity of the mechanical leg, its capability to estimate the risk of injuries to different mechanisms, and will show, with comparative tests, the possibility of the device to provide technical solutions to optimize pedestrian leg protection