EMPLOYEE WAS ON HIS KNEES WHILE INSTALLING A CORNER BOLT. THE BOTTOM DRILL STEEL DROPPED OUT OF THE HOLE AND WHEN THE EMPLOYEE STARTED TO PUT THE STEEL BACK IN, HIS KNEE SLIPPED CAUSING HIS HAND TO HIT THE CONTROL LEVER. THE LEVER RAISED THE STEEL AND PINCHED HIS LEFT INDEX FINGER BETWEEN THE TWO DRILL STEELS.