Three-Dimensional Computed Tomography Reconstructions Do Not Improve the Interobserver Reliability of the AO/Orthopaedic Trauma Association and Young and Burgess Pelvic Fracture Classifications

Purpose To evaluate the value of three-dimensional (3D) computed tomography (CT) scans on the interobserver and intraobserver reliability of AO/Orthopaedic Trauma Association (OTA) and Young and Burgess (YB) classifications for pelvic ring injuries. Methods Seven reviewers (four fellowship-trained orthopaedic trauma surgeons and three fellows) independently classified 36 pelvic ring injuries using radiographs and axial two-dimensional (2D) CT scan images and then repeated this process 2 months later with the addition of 3D CT images. Interobserver and intraobserver reliability was assessed. Results The interobserver reliability of the AO/OTA classification using 2D vs. 3D CT scans was considered fair ( k 0.23, CI 0.17–0.29) vs. slight ( k 0.16, CI 0.09–0.22), with no observed difference [mean difference (MD) − 0.07, CI 0.16–0.01]. The interobserver reliability of the YB classification using 2D vs. 3D CT scans was considered fair for both ( k 0.37, CI 0.32–0.42, vs. 0.37, CI 0.30–0.45), with no observed difference (MD − 0.0005, CI − 0.08 to 0.08). The intraobserver reliability of the AO/OTA vs. YB classifications was considered fair ( k 0.35, CI 0.26–0.44) vs. moderate ( k 0.49, CI 0.40–0.57), with the YB classification having higher kappa value (MD 0.13, CI 0.01–0.26, p = 0.03). Conclusion The addition of 3D CT scan reconstructions to radiographs and 2D CT did not improve the interobserver reliability of AO/OTA and YB classifications for pelvic ring injuries.