Here's how we do an elbow arthrogram:

1. Position the patient prone on the fluoroscopy table, with the elbow in approximately 90 degrees of flexion.
2. Plan a lateral (radial) approach by rotating the forearm so that the ulna rests on the table. In this position, the fluoroscopic image should resemble a lateral elbow radiograph.
3. Use a radiopaque instrument to localize the radial head.
4. Mark the skin site overlying the radiocapitellar articulation.
5. After antiseptic preparation of the skin, drape the area with sterile towels.
6. Prepare the local anesthetic solution.
7. Prepare the MR arthrography contrast solution.
8. Anesthetize the planned injection site.
9. Direct the needle between the capitellum and radial head. You should feel the needle tip drop into the joint.
10. After confirming needle position fluoroscopically, inject a small mount of contrast to confirm intra-articular position. Contrast should flow freely away from the needle tip, opacifying the joint capsule.
11. Take care to distend, but not overpressurize the joint.
12. Examine the elbow in an AP position to evaluate for gross contrast extravasation.
13. Document the intra-articular position of your needle and injection with fluoroscopic spot views.