The Role of Computed Tomography in Evaluating Intra-Articular Distal Humerus Fractures.

Computed tomography (CT) is often used to evaluate intra-articular distal humerus fracture patterns, but it increases radiation exposure and cost. We conducted a study to determine the effect of adding CT evaluation to plain radiographic evaluation on the classification of, and treatment plans for, intra-articular distal humerus fractures. Nine blinded orthopedic surgeons evaluated 30 consecutive fractures for classification and surgical approach. Evaluations were performed first using plain radiographs and then again using the same radiographs plus CT images. Statistical analysis was performed using the κ correlation coefficient and Cramer V testing. We hypothesized that adding CT images to plain radiographs would change the classification and treatment of these fractures and would improve interobserver agreement on classification and treatment. Intraobserver reliability (Cramer V) was fair (.393) for classification and moderate (.426) for treatment. Interobserver reliability (Cohen κ) did not improve with CT: For classification, κ was .21 without CT and .20 with CT; for treatment, κ was .28 without CT and .27 with CT. When classifying the fractures, attending surgeons chose the multiplanar fracture pattern 25.6% of the time without CT, and remained consistent at 23.3% with CT. Trainees chose this fracture pattern much less often without CT than with CT. Use of CT changed the treatment for multiplanar fractures (73.7% lateral approach vs 51.9% posterior approach with olecranon osteotomy). When added to plain radiographic evaluation, CT evaluation changes classification and treatment plans. Interobserver reliability did not improve. Less experienced surgeons were more likely to identify multiplanar fracture patterns with use of CT. We recommend performing CT for all intra-articular distal humerus fractures.