HE BACKED OVER ROCK OR BERM; DOZER JARRED HIM CAUSING HIS BACK TO HURT. HE SAT FOR A FEW MINUTES AND SAID HE WAS O.K. HE DID NOT WANT TO FILL OUT AN ACCIDENT REPORT. THE NEXT DAY HE WAS OFF FO R A DOCTOR'S APPOINTMENT BUT DID NOT SAY IT WAS FOR HIS BACK. STARTED LOSING TIME FROM WORK AUG. 11, 2003.