Seat Broken problems of the 2008 Mazda Tribute

Rear end collision 10/4/09. Stopped with turn signal on to turn into a parking lot. Rear ended, both front passengers had seat belts on. We were thrown forward and then backward breaking both front seats. Injuries back, hip, broken vertebra in neck from being thrown around. Very disappointed at the seat breaking causing us more body damage. Entire back of vehicle pushed in and buckled roof. Car was purchased 4/19/08 and had less then 6000 miles on it. This is a definite failure in the seats or very poor design on both seats.