CAMRT Radiography Practice Exam

In a patella skyline image, how can the joint space be better visualized if it appears closed?

1. Increase the angle of the central ray

2. Decrease the angle of the central ray

3. Flex the knee further

4. Extend the knee more

The correct answer is: Decrease the angle of the central ray

In the context of obtaining a patella skyline image, adjusting the angle of the central ray is crucial for accurately visualizing the joint space between the patella and the femur. When the joint space appears closed, it typically indicates that the imaging technique may not be optimal, which can occur if the central ray is not angled appropriately. By decreasing the angle of the central ray, you can achieve better alignment with the joint space. A more perpendicular angle to the patellofemoral joint allows for enhanced visibility of the gap between the patella and the femur. This adjustment helps to reveal any potential abnormalities, such as joint effusion or patellar subluxation, which might be obscured with inadequate angling. This approach is particularly relevant in radiographic imaging where precise angles can significantly influence the resulting diagnostic quality of the image. Therefore, focusing on this adjustment is essential for obtaining a clear view of the knee joint anatomy and understanding the functional relationship between the patella and the femur.