Each year, more than 250,000 hip fractures occur in the United States, resulting in considerable patient mortality and morbidity. The various types of adult proximal femoral fractures require different treatment strategies that depend on a variety of considerations, including the location, morphologic features, injury mechanism, and stability of the fracture, as well as the patient's age and baseline functional status. The authors discuss femoral head, femoral neck, intertrochanteric, and subtrochanteric fractures in terms of injury mechanisms, specific anatomic and biomechanical features, and important diagnostic and management considerations, including the diagnostic utility of imaging modalities. The authors review clinically important classification systems, such as the Pipkin, Garden, Pauwels, and Evans-Jensen classification systems, with emphasis on differentiating subchondral insufficiency fractures from avascular necrosis of the femoral head and typical subtrochanteric fractures from atypical (often bisphosphonate-related) subtrochanteric fractures. In addition, the authors describe the potential complications and management strategies for each fracture type on the basis of the patient's age and physical condition. A clear understanding of these considerations allows the radiologist to better provide appropriate and relevant diagnostic information and management guidance to the orthopedic surgeon.

Traumatic finger injuries account for a substantial number of emergency visits every year. Imaging plays an important role in diagnosis and in directing management of these injuries. Although many injuries can be managed conservatively, some require more invasive interventions to prevent complications and loss of function. Accurate diagnosis of finger injuries can often be difficult, given the complicated soft-tissue anatomy of the hand and the diverse spectrum of injuries that can occur. To best serve the patient and the treating physician, radiologists must have a working knowledge of finger anatomy, the wide array of injury patterns that can occur, the characteristic imaging findings of different finger injuries, and the most appropriate treatment options for each type of injury. This article details the intricate anatomy of the hand as it relates to common finger injuries, illustrates the imaging findings of a range of injuries, presents optimal imaging modalities and imaging parameters for the diagnosis of different injury types, and addresses which findings have important management implications for the patient and the orthopedic surgeon. With this fund of knowledge, radiologists will be able to recommend the most appropriate imaging studies, make accurate diagnoses, convey clinically relevant imaging findings to the referring physician, and suggest appropriate follow-up examinations. In this way, the radiologist will help improve patient care and outcomes. Online supplemental material is available for this article. (©)RSNA, 2016.

Ankle injuries occur in a predictable sequence, allowing a logical understanding of their classification once the injury mechanism is recognized. The Lauge-Hansen classification system was developed on the basis of the mechanism of trauma and is useful for guiding treatment. Three radiographic views of the ankle (anteroposterior, mortise, and lateral) are necessary to classify an injury with the Lauge-Hansen system. Two additional criteria are also necessary: the position of the foot at the time of injury and the direction of the deforming force. Because understanding the mechanism of trauma is fundamental to classifying the injury, three-dimensional movies were assembled for each classification, showing the sequence of ligament rupture and bone fractures that occurs with each type of traumatic mechanism. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.322115017/-/DC1.

Traumatic elbow injuries are commonly encountered in the emergency department setting, but their complexity and clinical significance often go unrecognized at the initial evaluation. Initial imaging in patients with elbow trauma should not only help identify major injuries that require immediate intervention but also allow detection of other, often more subtle injuries that may lead to instability or poor functional outcomes if appropriate treatment is delayed. Awareness and detection of these injuries may be improved by a better-developed and more intuitive understanding of the mechanisms that underlie the most common injury patterns. Ideally, such understanding should prompt appropriate early use of advanced imaging techniques. Traumatic elbow injuries should be described in the radiology report within the context of their clinical significance and their implications for management, information that is often best captured by the injury grading and classification systems used by the orthopedic surgery community. This article reviews the relevant anatomy and functional stability of the elbow and discusses common traumatic elbow injury patterns, including elbow dislocations as well as fractures of the distal humerus, radial head and neck, coronoid process, and olecranon. Less commonly encountered injury constellations that are clinically significant are also described. Injury patterns are explained in the context of the responsible force mechanism by using three-dimensional modeling and animation, with emphasis on the functional impact of associated secondary bone and soft-tissue injuries. The utility of cross-sectional imaging modalities such as computed tomography and magnetic resonance imaging in the acute care setting is discussed, and specific imaging guidelines are provided. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.333125176/-/DC1.