Fractures - General Principles

Imaging Techniques

X-ray

X-ray imaging is generally the first-line imaging technique for detecting fractures, due to its simplicity, low cost, and wide availability. In practice, X-rays are also frequently used as a standard method to monitor fracture healing.
The principle is based on absorption of X-rays by bone (see also X-ray/CT Technique module), which ultimately results in a two-dimensional image. The risk with two-dimensional images is that a fracture line may be invisible if it runs parallel to the direction of the X-ray beam (Fig. 13). Standard protocols therefore include (at least) two projections: often an anteroposterior (AP) view and a lateral view. Depending on the anatomical location, additional projections may be obtained, such as an oblique view for hand or foot fractures, or specific views (e.g., mortise view for ankle fractures). The clinical suspicion and the anatomy of the region of interest determine the choice of projections.
It is important to know that X-ray sensitivity for detecting fractures depends on fracture location and complexity.