EE WAS CLEANING THE TOP OF THE MACHINE HOUSE ON THE CROSS PIT SPREADER. IT HAD BEEN RAINING & THE AREA WAS SLICK. HIS FOOT SLIPPED OUT FROM UNDER HIM & HE FELL. HE FELL FORWARD & ATTEMPTED TO BREAK THE FALL WITH HIS HAND. THIS RESULTED IN A DISLOCATION OF HIS LEFT THUMB. THE THUMB WAS PUT BACK INTO PLACE AT THE E.R. & SPLINTED.