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In practice, radiography is the most commonly used imaging modality and remains a cost‐effective screening test for fracture identification. Radiographs principally provide structural information and are considered to have high specificity but carry the risk of false negative studies. Currently available portable generators have the output to produce excellent studies of the appendicular skeleton from the carpus and tarsus distally and parts of the head in all sizes of patient. Radiographs of the upper limb, and axial skeleton in larger patients, can succumb to image degradation through attenuation and scatter, and a higher output gantry‐mounted generator together with selective use of a grid improves image quality. This is particularly important in cases in which the radiographic features are subtle and susceptible to being obscured by low or limited energy transferred to the imaging plate. Utilizing air‐filled anatomic structures such as the trachea to reduce attenuation can also be beneficial to highlight lesions in shoulder and cranial thoracic locations (Figure 5.2) or the caudal lung over the thoracic vertebral bodies.

Figure 5.2 Medial to lateral radiograph of the cranial thorax made with the limb closest to the detector extended craniad. The position of the trachea provides a window of reduced attenuation allowing improved visualization of the rib fracture.

The radiographic technique utilized should provide excellent bone detail but allow for evaluation of adjacent soft tissues. Digital radiography, which includes computed radiography (CR) and direct digital radiography, also referred to as digital radiography, has superseded film/screen systems. While not without inducible artefacts, these are much more forgiving of exposure errors than traditional film/screen combinations. The fundamentals of patient preparation, source–image distance, collimation, positioning, appropriate beam angle and minimizing motion are prerequisites irrespective of the system used. When using digital formats, there are a plethora of post‐processing possibilities including alteration of window width and level, image sharpening, edge enhancement, noise reduction and smoothing filters which allow images to be optimized [2]. It should be noted that new information is not generated by image processing; it helps the information to be more readily perceived, thus increasing the detection rate for abnormalities [2].