BOTH SEAT BACKS COLLAPSED WHEN OUR HONDA WAS REAR-ENDED. WE (MY WIFE AND I) WERE STOPPED IN A TRAFFIC JAM (DUE TO AN ACCIDENT AHEAD) ON A DOWNTOWN FREEWAY (I-20 IN MONROE, LA). WE WERE REAR-ENDED AND KNOCKED INTO THE LEFT LANE WHERE WE TRAVELLED DOWN THE LANE FOR SEVERAL CAR LENGTHS, THEN HIT THE GUARD RAIL AND A CAR IN THE LEFT LANE (BY THAT TIME, AT A SLOW SPEED). THE SEAT BACKS OF BOTH SEATS COLLAPSED AND WE WERE LAID BACK. I WAS DRIVING AND PULLED UP WITH THE STEERING WHEEL TO MAINTAIN CONTROL OF THE CAR, ALTHOUGH WE WERE IN A SKID. THE HEAD REST OF THE DRIVER'S SEAT ALSO BROKE AWAY FROM THE SEAT BACK. MY WIFE AND I SUFFERED ONLY SOFT TISSUE DAMAGE IN OUR NECKS AND LOWER BACKS (STRAINS AND BRUISES), BUT I WAS WONDERING IF THE SEAT BACKS SHOULD HAVE COLLAPSED THE WAY THEY DID. THE INTERIOR OF THE CAR WAS IN TACT AND THE REAR CRUMPLE ZONES WORKED GREAT.*AK