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Objective: To evaluate screw prominence in the dorsal radius surface, after volar locked compression plate fixation, using five radiographic incidences.

Materials and Methods: We used a fresh radius and a Locked Compression Plate at the volar radius suface. We have fixed the transversal segment with five 2.4mm screws, in the longest length that would not pass the dorsal radial cortical (22mm, 24mm, 24mm, 22mm, 22 mm from radial to ulnar) (Series 1). Then, we have made a radiographic study with: postero-anterior, lateral, oblique semi-supinated, oblique semi-pronate and axial (75º within the table plane) views. After that, we have changed the first and forth screws, that were assigned at the dorsal radius sulcuses, for one size longer (2mm) screws (Series 2). Following, we have changed the same first and forth for screws for two sizes (4mm) longer ones then in Series 1 (Series 3). At last, we have changed all the screws for ones sized 24mm (Series 4). The radiographic incidences made at Series 1 were repeated in each Series. The screw prominency, in each incidence, was evaluated through the AutoCad^TM software.

Results: In Series 1, we have identified every screw covered. In Series 2 we have identified screw saliency at the axial incidence and minimum saliency at the oblique semi-pronated incidence. In Series 3, we have identified screw prominence at the oblique semi-pronated, oblique semi-supinated and axial incidences. At the lateral incidence the screws were at the Lister’s tubercle height.  In Series 4, there was minimum screw prominence at the semi-supinated incidence and obvius saliency at axial and semi-pronated incidences. The screw protusion was: 0.1mm at the semi-pronated incidence, while it was 2.3mm in screw 1 and 1.7 mm in screw 4 at axial incidence in Series 2; 0.4 mm at semi-supinated, 0,3mm at semi-pronated and 3.7mm in screw 1 and 3.4mm in screw 4 at axial incidence in Series 3; and finally, 2.2mm at semi.pronated, 0.3mm at semi-supinated e 2.0mm in screw 1and 2,9mm in screws 4 e 5 at axial incidence in Series 4. At the oblique incidences the prominent screw was not identified, as it was at the axial view.

Conclusions: The axial incidence was the more sensitive for screw prominence detection, allowing the identification of the screw that was protruding. The oblique views were more sensitive then the lateral view. The lateral incidence was the last sensitive, missing saliencies as long as 4mm.