I WAS RIDING IN A 2000 TOYOTA CAMRY WHEN THE VEHICLE WAS REAR-ENDED BY A 3/4 TONE TRUCK CARRYING A TRAILER WITH LAWN MAINTENANCE EQUIPMENT. I EXPERIENCED BACK INJURIES AS DID THE DRIVER. THE COMPLAINT THOUGH, IS THAT THE FRONT PASSENGER SEAT, WHERE I WAS SITTING WITH MY SEAT BELT IN USE, DID NOT WITHSTAND THE COLLISION. THE UPRIGHT PORTION OF THE SEAT WAS LAYING ON TOP OF THE BACK SEAT AFTER THE IMPACT. THIS CONTRIBUTED TO THE BACK AND SHOULDER INJURIES I RECEIVED. THE TOYOTA WAS NOT HIT FROM THE SIDE SO THE FAILURE OF THE SEAT WAS NOT THE RESULT OF A DIRECT IMPACT. THE SEAT SIMPLY CAME LOOSE AND FAILED TO MAINTAIN ITS POSITION AS I WAS THROWN FORWARD AND THEN BACK. AFTER THE ACCIDENT AND DURING THE REPAIR PROCESS, THE BODY SHOP CHECKED THE SEAT AND STATED THE LOCKING MECHANISM IS WORKING PROPERLY HOWEVER, THE SEAT HAS NOT BEEN "RIGHT" SINCE THE ACCIDENT. IT IS NOT PROPERLY POSITIONED. THE IMPACT WAS FAIRLY SUBSTANTIAL (UP TO $5000 IN DAMAGE - TRUNK WAS CRUMPLED AND OTHER DAMAGE) AND THE AIRBAGS DID NOT DEPLOY. JUST AFTER THE MOMENT OF IMPACT, I LOOKED OVER AT MY MOTHER WHO WAS DRIVING AND WATCHED IN HORROR AS SHE SNAPPED OVER THE STEERING WHEEL. I DON'T KNOW IF AIRBAG DEPLOYMENT REQUIRES A "HEAD-ON" BEFORE THE BAGS WILL DEPLOY BUT THIS SITUATION COULD HAVE BEEN MUCH WORSE (INITIALLY I WAS AFRAID MY MOTHER'S NECK HAD FRACTURED) AND HAD MY MOTHER GONE ANY FURTHER FORWARD, THE FAILURE OF THE AIRBAGS TO DEPLOY WOULD HAVE RESULTED IN A SERIOUS IF NOT FATAL INJURY. *N