In an AP shoulder radiograph, the central ray enters at which anatomical structure?

In an AP shoulder radiograph, the central ray enters at which anatomical structure?

• A. Glenoid process
• B. Acromion process
• C. Coracoid process
• D. Scapular notch

Answer: (C)

In an AP shoulder radiograph, the central ray is aimed through the shoulder joint area using a reliable anterior landmark—the coracoid process. The beam is centered just inferior to the coracoid process so it passes through the glenohumeral joint and projects the proximal humerus well within the image. This positioning helps visualize the joint for assessing dislocations or fractures and keeps the projection consistent. Entering at the glenoid itself would not align the beam to show the entire joint clearly; the acromion is a lateral projection and not used as the entrance point, and the scapular notch is not a practical centering landmark for this view.

In an AP shoulder radiograph, the central ray is aimed through the shoulder joint area using a reliable anterior landmark—the coracoid process. The beam is centered just inferior to the coracoid process so it passes through the glenohumeral joint and projects the proximal humerus well within the image. This positioning helps visualize the joint for assessing dislocations or fractures and keeps the projection consistent.

Entering at the glenoid itself would not align the beam to show the entire joint clearly; the acromion is a lateral projection and not used as the entrance point, and the scapular notch is not a practical centering landmark for this view.