gms | German Medical Science

Objectives/Interrogation: Volarly displaced intra-articular fracture of the distal radius with volar lunate facet fragments are very difficult for internal fixation. The object of this study is to evaluate the results following polyaxial locking plate fixation of the fractures.

Methods: A retrospective study was conducted to identify patients who had been treated with polyaxial locking plates (Aptus2.5 plate, Medartis, Basel) for unstable volarly displaced intra-articular fracture of the distal radius. 49 patients 51 wrists were identified with an average age of 63.3 years old and with an average follow-up period 12.3 months. Fracture types were classified type B3 30 cases, C2 7 cases, C3 14 cases in AO classification. We evaluated various parameters with X-rays included calpal translation, size of volar lunate facet fragments and coverage rate of locking plate with CT, range of motion, and Mayo modified wrist score.

Results and Conclusions: All fractures were united. Final ulnar variance averaged 0.6mm, radial inclination was 21.7º, and volar tilt was 13.4° and carpal translation was corrected except initial 2 cases. The average range of motion were: flexion-extension 124° (94.8% of the opposite extremity); pronation-supination 172° (95.1%); grip strength was 12.4 kg (72.1%). There were no complications. Mayo modified wrist score were averaged 88 points.

This study for unstable volarly displaced intra-articular fracture of the distal radius, resulted in union, good to excellent alignment and wrist motion. Especially, polyaxial locking plate fixation enabled to place plate distally by changing of the screw direction. This feature leaded to stabilize volar lunate facet fragments by buttress effect. Polyaxial locking plate fixation were very useful for the fractures.