EE GOT OFF OF DOZER TO MOVE GUARD AND STEP OUT OF ROADWAY. BOLTS HAD BROKEN AND GUARD FELL OFF OF DOZER. ABOUT 1 HR LATER EE STATED BACK WAS HURTING. EE CONTINUED TO WORK UNTIL 2-10-03 WHEN AF TER A VISIT TO HEALTH UNIT HE WAS PUT ON RESTRICTED DUTY.