Development and initial clinical use of an aiming device for distal boring in interlocking nailing without roentgen image intensifier for the unreamed tibial nail

An aiming technique for an unreamed tibial nail was developed, which uses the relatively constant distance between the first transverse distal nail hole and the anterior aspect of the tibia. This aiming device is set at a distance of 12.3 mm from the anterior cortex, and fine tuning is finally resolved by use of a "working channel" with a 10 mm diameter from the medial side. The aiming system was tested in 20 cases in a video-documented prospective study using the unreamed tibial nail (UTN, Synthes) between July 1993 and March 1995. In all cases (100%) distal locking could be performed without image intensification. With a high percentage (55%) of open fractures (3 O3B fractures) the total operation time was 108 min (median, range 60-180 min). The time for distal locking (always 3 bolts) was 15.5 min (median, range 8.0-39.0 min), while the time for proximal locking (average 1.6 +/- 0.7 bolts) was 4.5 min (median, range 3.0-15.0 min). There were no major intra- or postoperative complications related to the aiming system. The major advantages are that it is not necessary to have image intensification for distal locking, there is a reduction in radiation exposure for the surgeon, and the drill holes are very precise.