The present bone implant is a cannulated screw/nail or combination having end, middle and head threads as well as unthreaded portions along the length of the shaft. The pitch of the head threads is always less than the middle threads. Variations include a two-part construction with a narrow protrusion having narrow-protrusion threads of opposite hand, or the inclusion of at least first middle threads and second middle threads of different pitch. The implant provides bone compression engineering heretofore unavailable with prior known compression screws.
