EMPLOYEE STATED THAT HE HAD HIS LEFT HAND ON TOP OF THE CANOPY FOR THE ROOF BOLT MACHINE. AS HE WAS DRILLING A HOLE TO INSTALL A ROOF BOLT, THE DRILL STEEL DRILLED THROUGH A CRACK IN THE MINE ROOF CAUSING THE CANOPY TO GO AGAINST THE ROOF. HIS LEFT MIDDLE FINGER WAS CAUGHT BETWEEN THE MINE ROOF AND THE CANOPY.