Final answer:
Arthrography involves using a contrast agent for joint imaging and is employed by rheumatologists to diagnose joint conditions. While the question does not specify the precise needle size for shoulder arthrography, a range from 20 to 25 gauge needles is generally used depending on various factors.
Step-by-step explanation:
Arthrography is a type of medical imaging technique used to visualize the structures within joints, which includes cartilage, tendons, and ligaments. Rheumatologists can use it to diagnose conditions such as rheumatoid arthritis (RA) by injecting a contrast agent into the joint space, making it opaque to X-rays. This procedure is especially useful as it can detect early degenerative changes in joint cartilage before the bone is affected. With shoulder arthrography, selecting the correct needle size is important for a successful procedure but the specific needle size was not provided in the question.
Typically, a size ranging from 20 to 25 gauge depending on the patient's anatomy and the viscosity of the contrast agent being used would be appropriate. However, the exact needle size for shoulder arthrography should always be determined by a healthcare professional based on individual patient needs and the specifics of the procedure. This ensures a balance between patient comfort and the technical success of the arthrogram.