In a transthoracic lateral projection, which anatomical structures should be visible through the lung field?

In a transthoracic lateral projection, the primary focus is on visualizing the proximal humerus along with specific structures associated with it, such as the greater tubercle. This projection is designed to provide a clear view of the upper portion of the humerus, which is crucial for assessing fractures or other injuries in that area.

The proximal humerus is the section that connects to the shoulder joint, and it is significant in terms of its anatomical landmarks, including the greater tubercle, which serves as an important site for muscle attachment. The visibility of these structures through the lung field during the projection is essential for a complete assessment, as it allows practitioners to evaluate the condition of the humerus without interference from surrounding anatomical structures.

Understanding the positioning and the focus in a transthoracic lateral view helps to clarify why the chosen answer relates directly to key anatomical structures that should be visible, ensuring effective diagnosis and treatment planning for upper extremity conditions.