EMPLOYEE WAS HELPING THE MECHANIC WHO WAS PUTTING UP THE BELLY PAN ON A D-11 DOZER. WHILE TWISTING AROUND, HE FELT A TWINGE IN HIS RIGHT KNEE. HE CONTINUED TO WORK BUT HIS KNEE CONTINUED TO BO THER HIM SO HE FINALLY DECIDED TO GO TO THE DOCTOR ON 4-2-02. HE NOTIFIED HIS FOREMAN FOR THE FIRST TIME ON APRIL 3RD CONCERNING THIS ACCIDENT.