Three consistent events were identified during each test, in the following sequence; 1. initial compressive femur force, 2. secondary tensile femur force, and 3. rearward pelvis acceleration peak. In addition to pelvic contact with the seatback, in some cases the loading in the femur was influenced by contact between the seat pan and the back of the tibia just below the knee. The larger, male occupants experienced higher magnitudes of femur compression as the vehicle was impacted from the rear. The smaller, female occupants experienced predominately femur tension. Pelvic acceleration data corroborated these findings. Femur forces were consistent between both legs, indicating that there was little torsion applied to ATDs during the rear-end crash tests.