When performing a posteroanterior wrist radiograph with ulnar deviation, where should the central ray be centered?

In a posteroanterior wrist radiograph with ulnar deviation, the central ray should be centered at the scaphoid. This positioning is important because the scaphoid bone is commonly involved in wrist injuries, particularly in cases of fractures. By centering the central ray over the scaphoid, the radiograph provides a clear and unobstructed view of this bone, allowing for better evaluation and diagnosis.

Additionally, when the wrist is positioned in ulnar deviation, it helps to open up the spaces between the carpal bones and provides a clearer image of the scaphoid and its relationship to the surrounding anatomical structures. This technique minimizes superimposition and enhances the visibility of the scaphoid, which can be critical in identifying fractures or other pathologies in this area.

While other bones such as the lunate, triquetrum, and capitate play important roles in wrist anatomy, centering the central ray at the scaphoid is the most effective approach for achieving the desired outcomes of clarity and diagnostic accuracy in the radiographic examination of the wrist.