Which of the following must be clearly visible on a diagnostic posteroanterior wrist radiograph with radial deviation?

The correct answer, which identifies that the carpals on the medial side must be clearly visible on a diagnostic posteroanterior wrist radiograph with radial deviation, is based on important anatomical and radiographic principles.

When performing a posteroanterior (PA) view of the wrist, especially in a position of radial deviation, the imaging technique allows for optimal visualization of certain structures in the wrist. Radial deviation moves the wrist towards the radial or thumb side, which in turn increases the space between the ulnar side and the structures of the wrist. This positioning enhances the visualization of the carpals, particularly those on the medial side (such as the pisiform and triquetrum), which may otherwise be obscured in anatomical positions or different views due to their location relative to the forearm and the radius.

In clinical practice, identifying the alignment and the contours of the carpal bones on the medial aspect during this view is crucial for diagnosing issues such as fractures or ligamentous injuries that might be more common in that area under stress or deviation. Hence, having a clear view of the medial carpals is vital for accurate assessment.

Understanding the anatomical relationships and radiographic techniques helps emphasize the importance of this specific view in evaluating potential path