Sign IM Nail and Interlocking Screw System Technique Manual page 18

Sometimes the cannulated slot finder will not proceed
through the hole in the near cortex because it is wider than
the solid slot finder. Use the screw hole broach to enlarge
the hole if this occurs.
If either slot finder does not enter the slot in the nail after
rotation of the nail, remove the target arm; use the
curved slot finder, figure 18, to locate the slot in the nail.
Find the slot in the nail by combination of rotation of the
nail by rotating the L-handle and slight pressure to push in
the curved slot finder. The surgeon should both rotate the
L-handle and manipulate the curved slot finder. Once the
slot in the nail has been discovered by "SIGN feel," insert
the cannulated slot finder and drill the hole in the far
cortex.
If rotating the cannulated slot finder results in
the "SIGN feel," place the small drill bit
through the cannulated slot finder to drill a
hole in the far cortex, figure 19.
Fig. 17
18
Screw Hole Broach
Step Drill
Fig. 18
Fig. 19