Distal Humerus Traction Radiographs: Is the Interobserver and Intraobserver Reliability Comparable With Computed Tomography?

To compare the interobserver and intraobserver reliability of traction radiographs with 2-dimensional computed tomography (2D CT) in distal humerus fracture classification and characterization.Randomized controlled radiographic review of retrospectively collected data.Academic Level 1 trauma center.Skeletally mature patients with intra-articular distal humerus fractures with both traction radiographs and CT scans were reviewed by 11 orthopaedists from different subspecialties and training levels.The intervention involved traction radiographs and 2D CT.The main outcome measurements included interobserver and intraobserver reliability of fracture classification by the OTA/AO and Jupiter-Mehne and determination of key fracture characteristics.For the OTA/AO and Jupiter-Mehne classifications, we found a moderate intraobserver agreement with both 2D CT and traction radiographs (κ = 0.70-0.75). When compared with traction radiographs, 2D CT improved the interobserver reliability of the OTA/AO classification from fair to moderate (κ = 0.3 to κ = 0.42) and the identification of a coronal fracture from slight to fair (κ = 0.2 to κ = 0.34), which was more pronounced in a subgroup analysis of less-experienced surgeons. When compared with 2D CT, traction radiographs improved the intraobserver reliability of detecting stable affected articular fragments from fair to substantial (κ = 0.4 to κ = 0.67).Traction radiographs provide similar diagnostic characteristics as 2D CT in distal humerus fractures. For less-experienced surgeons, 2D CT may improve the identification of coronal fracture lines and articular comminution.