An arthrogram is an exam in which contrast material is injected into the affected joint. Joint injections can be for an x-ray arthrogram, or simply used as a guide to insert contrast into the joint for an MRI Arthrogram. It is used to view the soft tissue structures of your joint (tendons, ligaments, muscles) that are not seen on a plain x-ray, and helps the radiologist evaluate the need for joint replacement procedures.
An arthrogram is performed to evaluate persistent, unexplained joint pain, swelling, or abnormal movement in the ankle, wrist, shoulder, hip, and knee.