Comparison of ultrasound and dorsal tangential view for dorsal cortex screw penetration in volar plating of the distal radius

Abstract

We compared the accuracy of the fluoroscopic dorsal tangential view (DTV) and an ultrasound (US) examination in detecting dorsal screw penetration during volar distal radius plating. In six fresh cadaveric distal radii, seven periarticular locking screws in two rows for each plate were inserted according to the measured length using a depth gauge and then replaced with another that was 1 and 2 mm longer, respectively. The actual protruded length of each screw was determined using computed tomography (CT) images. The accuracy of US and DTV measurements was determined using the intraclass correlation coefficient (ICC), as both measurements were compared with CT measurements. The ICC of US and DTV was 0.96 and 0.75, respectively, for all screws. After excluding the data for proximal-row screws, the ICC of US remained unchanged at 0.96, and that of DTV improved to 0.86. The ICC of US was significantly higher than that of DTV (p < 0.01). US had a 100% detection rate for screw protrusion of more than 1.0 mm. US examination showed excellent consistency with CT measurements and its accuracy was not affected by screw location. US might thus be a practical tool for detecting dorsal cortex screw penetration during volar distal radius plating.

Keywords: fluoroscopy; radius fractures; screws penetration; ultrasound; volar plating.