Objectives: Understanding history, physical examination, and ultrasonography (US) to diagnose extremity fractures compared with radiography has potential benefits of decreasing radiation exposure, costs, and pain and improving emergency department (ED) resource management and triage time. Methods:The authors performed two electronic searches using PubMed and EMBASE databases for studies published between 1965 to 2012 using a strategy based on the inclusion of any patient presenting with extremity injuries suspicious for fracture who had history and physical examination and a separate search for US performed by an emergency physician (EP) with subsequent radiography. The primary outcome was operating characteristics of ED history, physical examination, and US in diagnosing radiologically proven extremity fractures. The methodologic quality of the studies was assessed using the quality assessment of studies of diagnostic accuracy tool (QUADAS-2).Results: Nine studies met the inclusion criteria for history and physical examination, while eight studies met the inclusion criteria for US. There was significant heterogeneity in the studies that prevented data pooling. Data were organized into subgroups based on anatomic fracture locations, but heterogeneity within the subgroups also prevented data pooling. The prevalence of fracture varied among the studies from 22% to 70%. Upper extremity physical examination tests have positive likelihood ratios (LRs) ranging from 1.2 to infinity and negative LRs ranging from 0 to 0.8. US sensitivities varied between 85% and 100%, specificities varied between 73% and 100%, positive LRs varied between 3.2 and 56.1, and negative LRs varied between 0 and 0.2. Conclusions:Compared with radiography, EP US is an accurate diagnostic test to rule in or rule out extremity fractures. The diagnostic accuracy for history and physical examination are inconclusive. Future research is needed to understand the accuracy of ED US when combined with history and physical examination for upper and lower extremity fractures.ACADEMIC EMERGENCY MEDICINE 2013; 20:1-15 © 2013 by the Society for Academic Emergency Medicine E xtremity injuries are among the most frequent reasons for visiting the emergency department (ED). These injuries are significant, comprising over 42.4 million injury-related visits to the ED in 2006. 1The typical work-up of the injured patient generally involves a medical provider obtaining a history and physical examination, often followed by radiologic imaging. However, many times the radiologic imaging may be negative or inconclusive, which calls to question whether the imaging contributed to the management or outcome of the patient. Studies have shown that often the imaging obtained is unnecessary and results in radiation exposure to patients and increased ED wait times. 2There is a low rate of positive radiography when assessing for fractures as evidenced by a retrospective review by Bentohami et al.,3 in which only 50% of upper extremity x-rays showed fractures, and another ...