Effect of Downsized Screw Selection on Bone Healing and Postoperative Complications in Volar Plating of Distal Radius Fractures.

When performing volar plating of distal radius fractures, selecting downsized subchondral screws may prevent dorsal screw penetration (DSP), which is a risk factor for extensor tendon rupture. However, downsizing may cause loss of reduction or poor bone healing. This prospective study investigated the effect of downsized screw selection on bone healing and postoperative complications. A total of 115 patients with postoperative follow-up longer than 6 months comprised the study population. Using a depth gauge, screws that were 2-mm shorter than the measured value were selected. The DSP then was checked using dorsal tangential view (DTV) radiographs during surgery and at final follow-up. Baseline data included bone healing, loss of reduction of radiological parameters, DSP location, and postoperative complications. To assess DSP on DTV radiographs, the dorsal surface of the radius was divided into the radial and ulnar sides at the Lister tubercle, and each was further divided into 2 equal regions. These 4 regions were defined as zones 1 to 4 from the radial side. A total of 114 patients (99%) showed bone healing. Mean loss of reduction was approximately 1° and within 1 mm in radiological parameters. Eleven patients (9.6%) showed DSP during surgery or at final follow-up despite using 2-mm downsized screws. The most common site of DSP was zone 3. Extensor pollicis longus rupture occurred in 2 patients (1.7%) despite no DSP. Downsized screw selection provided a high rate of bone healing with minimum loss of reduction and a low complication rate. The extensor tendon can be torn regardless of DSP. [Orthopedics. 2021;44(2):e259-e265.].