What is the cassette size for the external rotation of the shoulder?

The external rotation view of the shoulder often utilizes a cassette size of 10" x 12". This size is ideal because it accommodates the anatomy being imaged and provides adequate coverage of the shoulder joint area while being manageable for positioning. The dimensions allow for optimal visualization of key structures, ensuring that important aspects like the humeral head and glenoid cavity are clearly depicted in the image.

Smaller sizes, such as 8" x 10", may not capture the full extent of the shoulder joint and could lead to reduced diagnostic quality. Larger sizes might be cumbersome, affecting positioning and alignment during the imaging process. Thus, the 10" x 12" cassette strikes an appropriate balance, facilitating an effective and accurate external rotation positioning of the shoulder.