EE STRUCK ON LOWER LEG WHILE ATTEMPTING TO EMTPYWHEELBARROW INTO UNILOADER BUCKET. OPERATOR WAS APPARENTLY EXITING UNILOADER TO ASSIST WITH THE WHEELBARROW AS HE WAS REACHING TO RAISE THE SAFE TY RESTRAINT BAR, HE BUMPED ONE OF THE MOTION LEVERS CAUSING THE MACHINE TO MOVE FORWARD SLIGHTLY. THE BUCKET STRUCK INJ EE'S LEG