Technical difficulties of removal of locking screw after locking compression plating.

INTRODUCTION: As there are few reports on the difficulties of removing the locking compression plate (LCP), we prospectively investigated the incidence and difficulties in 58 patients in whom various types of LCPs were taken.

METHODS: From January 2004 to December 2007, we have removed 159 5.0-self tapping locking screws and 279 3.5- self tapping locking screws. All of the operations were performed by experienced trauma surgeons. All of the screws were inserted with the use of torque limiting attachment according to the manufacturer's recommendation. During the same period of time we have removed 198 AO-3.5 cortical and 4.0 cancellous screws from various sites.

RESULTS: All of 159 5.0-self tapping locking screws were removed without difficulties. A total of 24 out of 279 3.5- self tapping locking screws were removed with many difficulties due to the stripping of the hexagonal recess. The use of conical extraction screw which was developed especially for the removal of stripped locking screws was successful in only six screws. We have removed plates by cutting the plate with metal cutting saw. We describe useful technical trick to remove the plate when there is only one screw left stripped. Compared to the locking screws, only one of 198 3.5-cortical screws was stripped.

CONCLUSION: Care should be taken at the time of removal of the locking compression plate, especially for the 3.5-locking screws.