EMPLOYEE WAS SCRAPING OUT CRUSHER, HE HAD USED A LADDER TO CLIMB INTO CRUSHER. AS HE ATTEMPTED TO CLIMB OUT, HIS FOOT SLIPPED ON LADDER CAUSING HIM TO FALL. HE GRABBED THE UPPER EDGE OF THE OPENING, WHICH KEPT HIM FROM FALLING. HOWEVER, AS HE WAS HANGING HIS BODY SWUNG BACK INTO THE LOWER EDGE OF THE CRUSHER, STRIKING THE EDGE. EE OVEREXTENDED HIS BACK.