Role of Intraoperative 2D and 3D Fluoroscopy in Identifying Malposition of Screws in Surgical Fixation of Intra-articular Distal Radius Fractures in Comparison to Post-operative Computed Tomography.

Introduction: Functional outcomes in distal radius fractures rely on effective surgical fixation and anatomical joint restoration. Volar locking plating is essential for stabilizing intra-articular distal radius fractures. Intraoperative standard 2D fluoroscopic images are typically utilized during the surgical fixation to evaluate the reduction and malposition; however, there has been a recent shift toward the intraoperative 3D fluoroscopy for this purpose, because of the limited role of 2D imaging, which might not give a promising surgical outcome. Objectives: To evaluate the progressive diagnostic accuracy and performance of intraoperative 3D fluoroscopy compared with intraoperative standard 2D fluoroscopy for detecting screw prominence or malposition during volar plating of distal radius fractures, using post-operative computed tomography (CT) as the reference standard, and to quantify intraoperative screw revisions prompted by imaging. Design: Retrospective single-cohort diagnostic accuracy study. Materials and Methods: A total of 52 adult patients with distal radius fractures were selected who underwent surgical fixation within a year with a locking compression plate. All patients had intraoperative 2D fluoroscopy, followed by intraoperative 3D fluoroscopy performed on the affected wrist during the surgery, and subsequently underwent post-operative CT scan in the ward. Prominent screws were defined as ≥1 mm dorsal cortical protrusion. Intraoperative revisions prompted by imaging were recorded. The diagnostic performance of 3D fluoroscopy results was calculated in comparison with Post-operative CT scan results. Results: Sixty fractures (350 screws) were evaluated. Intraoperative standard 2D fluoroscopy identified 6/350 screws (1.71%) requiring intraoperative exchange. Intraoperative 3D fluoroscopy identified additional screw-related findings not evident on 2D imaging in 32/60 constructs (53.4%), including 20 screws with dorsal cortical extension; 18 were exchanged intraoperatively. Post-operative CT scan identified 10 additional screws with >1 mm dorsal prominence (1.20-2.24 mm) missed by both intraoperative 2D/3D fluoroscopy; 8/10 (80%) were located in dorsal compartments, and none were intra-articular. For dorsal/intra-articular screw detection, intraoperative 3D fluoroscopy demonstrated 71.4% sensitivity and a negative predictive value >97.0%. Conclusion: Intraoperative 3D fluoroscopy successfully identified dorsal screw prominence compared with intraoperative standard 2D imaging and helped in the correct positioning of the screws. However, post-operative CT scan still identified additional prominent screws missed intraoperatively. We highly recommend utilizing intraoperative 3D fluoroscopy imaging to prevent the need for revision surgeries.