Abstract
Bone has one of the highest acoustic densities (AD) in the human body. Traditionally, bone has been considered to be a hindrance to the use of ultrasound (US), as US waves are reflected by the dense matrix and obscure underlying structures. The intense wave reflection, however, can clearly illustrate the cortical bony anatomy of long bones, making cortical disruption obvious. Ultrasound can be used at the bedside concurrently with the overall trauma resuscitation, and may potentially limit the patient's and treating team's exposure to ionizing radiation, corroborate clinical findings, and augment procedural success. The extended focused assessment with sonography for trauma (EFAST) is an essential tool in the resuscitation of severe torso trauma, frequently demonstrating intra-pericardial and intra-peritoneal fluid, inferring hemo/pneumothoraces, and demonstrating cardiac function. Although it is typically considered as a diagnosis of exclusion, multiple long-bone fractures may be a source of shock and can be quickly confirmed at the bedside with EFAST. Further, the early detection of long-bone fractures can also aid in the early stabilization of severely injured patients. Sonographic evaluation for long-bone fractures may be particularly useful in austere environments where other imaging modalities are limited, such as in the battlefield, developing world, and space. While prospective study has been limited, selected series have demonstrated high accuracy among both physician and para-medical clinicians in detecting long-bone fractures. Pitfalls in this technique include reduced accuracy with the small bones of the hands and feet, as well as great reliance on user experience.