WHILE DRIVING HOME FROM WORK, I HEARD A NOISE THAT SOUNDED LIKE SOMEONE HIT MY HEADREST WITH A BAT. AT THE SAME TIME, MY HEAD WAS THROWN FORWARD, BRIEFLY CAUSING ME TO TAKE MY EYES OFF THE ROAD AND SWERVE SLIGHTLY WITHIN MY LANE.. I WAS DRIVING AT APPROXIMATELY 55 MPH, ON A HEAVILY TRAVELED STATE ROAD, ALONE IN MY CAR. I WASN'T ABLE TO PULL OVER RIGHT AWAY. ONCE I COULD SAFELY PULL OVER, I NOTICED MY DRIVER SIDE HEADREST DID NOT LOOK LIKE MY PASSENGER SIDE. IT WAS SEPARATED AND PUSHED FORWARD INTO MY SEAT SPACE. THERE WERE ALSO LOOSE PLASTIC PIECES INSIDE. I HAD NECK PAIN FOR APPROXIMATELY 4 DAYS FOLLOWING.*DT CONTACT DID NOT SEEK MEDICAL HELP. VEHICLE WAS NOT ON THE RECALL LIST AND IS NOT FIXED.*JB