A NEW TECHNIQUE FOR THE DISTAL LOCKING OF SOLID AO UNREAMED TIBIAL NAILS

Proximally mounted distal aiming systems have failed primarily because of nail deformation during insertion. A mechanical aiming device for the insertion of distal locking screws for solid unreamed AO tibial na ils was developed and was tested in twenty unreamed solid tibial naili ng procedures in a video-documented prospective clinical study. The ra te of accurate screw placement, time expended, complications, and outc ome for each patient were recorded. Distal locking was performed succe ssfully in all cases without image intensification. Although a high pe rcentage (55%) of fractures were open, the total mean operative time w as 108 minutes (range, 60 to 180 minutes) and the mean time for distal locking (three screws) was 15.5 minutes (range, 8.0 to 39.0 minutes). Notable drill-nail contact occurred in 15 percent of the distal screw s placed, demonstrating accurate aiming and drilling. There were no ma jor intra-or postoperative complications related to the distal aiming system.