Where should the central ray be directed for a PA hand x-ray?

For a PA hand x-ray, the central ray is directed through the head of the 3rd metacarpal. This positioning is crucial because it allows for an optimal view of the anatomical structures of the hand, including the phalanges, metacarpals, and the carpal bones. Directing the central ray at the head of the 3rd metacarpal provides a clear image of the metacarpophalangeal joints and minimizes distortion of the surrounding structures. This positioning also helps to ensure that the entire hand is captured in the image, providing a comprehensive view that is essential for accurate diagnosis and assessment of any potential injuries or conditions affecting the hand.

The head of the 3rd metacarpal is centrally located and ensures that all areas of the hand are evenly exposed, which is important for clinical evaluation. Being the axial landmark that aligns with the center of the hand, this approach promotes consistent and repeatable results for radiographic examinations.