WE WERE INVOLVED IN AN ACCIDENT ON I270 IN ST.LOUIS, MO. A SEMI- TRUCK DOING APPROXIMATELY 35 MPH STRUCK US IN THE REAR AND FORCED US INTO THE PICK UP TRUCK IN FRONT OF US. THE AIR BAGS DID NOT DEPLOY, DESPITE THE SQUARE FRONT TO REAR IMPACT. THE FRONT PASSENGER SEAT IN MY VEHICLE BROKE, TWISTING THE PASSENGER TO THE SIDE, FACING THE STEERING WHEEL.*AK