The purpose of this study was to evaluate the incidence and possible causes of stripped locking screws that make difficult to remove the locking compression plate. We also tried to find the useful methods to remove the stripped locking screws.

Between May 2005 and January 2009, 84 patients who underwent operations for removal of locking compression plate were included in this study. We removed 298 3.5-mm locking screws and 289 5.0-mm locking screws in these patients. We retrospectively investigated the incidence and possible causes of stripped locking screws and evaluated the pros and cons of the methods that we have used to remove the stripped locking screws.

17 out of 298 3.5-mm locking screws (5.7%) and 2 out of 289 5.0-mm locking screws (0.7%) were encountered with difficulties by hexagonal driver during removal because of the stripping of the hexagonal recess. First we used the conical extraction screw for all the stripped locking screws and only 3 screws were removed successfully. We removed 3 screws by cutting the plate around the stripped locking screw and twisting the plate with the screw and we removed 1 screw by the use of hallow reamer after cutting the plate. Twelve screw shafts were left except grinding of screw head by metal-cutting burr. There was one iatrogenic re-fracture in whom we have used with hallow reamer.

At the time of locking compression plate removal, difficulties of locking screw removal due to the stripping of the hexagonal recess should be expected and surgeon must prepare several methods to solve this problem.