Diagnostic accuracy of two-dimensional and three-dimensional imaging and modeling of radial head fractures.

UNLABELLED: To tests the hypothesis that classification and characterization of fractures of the radial head is more accurate with 3D than 2D computed tomography images and radiographs, using a prospective study design with intraoperative inspection as the reference standard. Treating surgeons and first assistants completed a questionnaire assigning a fracture type according to the Broberg and Morrey modification of Mason's classification, evaluating selected fracture characteristics, and electing preferred management based upon radiographs and 2D images alone; then adding 3D-CT; then 3D printed physical models; and finally intra-operative visualization. The addition of the 3D CT and physical models improved the sensitivity for fracture line separating the entire head from the neck, comminution of the radial neck, fracture involving the articular surface, articular fracture gap greater than 2 mm, impacted fracture fragments, greater than 3 articular fragments, and articular fragments judged too small to repair. There were no significant differences in diagnostic performance with the addition of 3D models. The addition of 3D CT and models improved the reliability of Broberg and Morrey classification. We conclude that 3DCT and 3D physical modeling provide more accurate fracture classification and characterization of fracture of the radial head with less proposed variability in treatment. We did not demonstrate a clear advantage for modeling over 3DCT reconstructions. LEVEL OF EVIDENCE: Diagnostic, Level I.