Although pediatric musculoskeletal (pMSK) radiograph interpretation is widespread, the particular radiological characteristics at risk of inaccurate diagnosis are unclear. For a study, researchers identified the radiograph characteristics that caused diagnostic interpretation difficulties for emergency doctors (EPs) analyzing pMSK radiographs. EPs interpreted 1,850 pMSK radiographs using a web-based platform and used one-parameter item response theory to calculate interpretation difficulty scores for each radiograph in 13 body regions. They compared difficulty scores based on the presence or absence of a fracture and fracture site and morphology, if appropriate; significance was corrected for multiple comparisons. An expert panel examined the 65 most often misdiagnosed fracture-negative radiographs to identify imaging abnormalities that were misinterpreted as fractures. 

They used data from 244 EPs, yielding 185,653 distinct interpretations. For elbow, forearm, wrist, femur, knee, and tibia-fibula radiographs, individuals without a fracture had greater interpretation difficulty ratings than those with a fracture; for hand, pelvic, foot, and ankle radiographs, the converse was true (P<0.004 for all comparisons). The descriptive study found that particular normal anatomy, overlapping bones, and external artifacts from muscle or skin folds were frequently misdiagnosed as fractures. The difficulty score differed significantly by anatomic site of the fracture in the elbow, pelvis, and ankle (P<0.004 for all comparisons). Growth plate fractures of the ankle and elbow, fibular avulsion, and humerus condylar fractures were more difficult to identify than other fracture patterns (P<0.004 for all comparisons). In pMSK radiograph interpretation for EPs, investigators discovered meaningful learning opportunities.