Final answer:
To obtain a clear erect lateral projection of the sternum, the patient's hands must be positioned from palms facing backward to palms facing forward, in line with standard anatomical positioning.
Step-by-step explanation:
For an erect lateral projection of the sternum, the patient's hands should be positioned from the palm backward position to the palm forward position. This positional adjustment refers to the anatomical position where the body stands upright, feet at shoulder width, toes forward, and palms of the hands facing forward. It aligns the upper limbs to the sides, ensuring that they do not obstruct the view of the sternum during the projection.
Following the anatomical standards, the hands and arms should neither interfere with the imaging area nor compromise the projection's quality. It is crucial to position the hands correctly for accurate visualization of the sternum, which consists of the manubrium, body, and xiphoid process, essential for thoracic cage anatomy and procedures like CPR, where hand positioning on the sternum is significant for life-saving compressions.