INJURED WAS CHANGING FUEL FILTER ON A DOZER. HIS FOOT WAS POSITIONED ON THE TRACKS AND HIS RT. FOOT SLIPPED CAUSING HIM TO FALL, CAUSING A MUSCLE STRAIN & STRAINED LIGAMENTS TO RT. LEG. HE RET URNED TO WORK UNTIL 5-7 AND RETURNED TO DR ON 5-10 TO BEGIN THERAPY.