A system that enables targeting of an instrument placed within a drill
bushing aligns the axis of a drill bushing with the axis of a transverse
hole in an intramedullary nail. The system includes a probe having an
elongated member with a distal end, a magnet that is polarized along its
longitudinal axis that is mounted perpendicularly to the distal end of
the elongated member; and a processor executing programmed instructions
to determine a position and orientation of the magnetic sensor array with
respect to the targeting magnet.