Background
An arthrogram is a particular type of radiograph whereby a contrast medium is used to visualize a joint abnormality. Despite the introduction of more advanced diagnostic imaging modalities, such as CT and MRI, arthrography remains a popular diagnostic tool, as it is not a technically difficult procedure to perform, and the findings are easier to interpret than are those obtained using ultrasound, CT or MRI.1
Historical Overview
During the last century, arthrography has evolved from crude approaches to more advanced CT and MR arthrographic techniques.2 Arthrography was most widely used during the 1960s and 1970s, but indications for its use in many joints decreased after the introduction of cross-sectional imaging modalities. Nevertheless, arthrography continues to provide valuable anatomic information about the joints and provides accurate depiction of internal derangement.2
Description
For arthrography, the area to be visualized is cleaned, and a local anesthetic is injected into the area around the joint. If fluid is present in the joint, it may be aspirated and sent to the lab for further analysis. A contrast agent (eg, iodine solution, air), or combination of agents, is injected into the joint. After the contrast agent is injected, the site is sealed, and the patient may be asked to move the joint to distribute the contrast. The purpose of contrast agents is to highlight details of the structures under study by making them opaque.
A normal arthrogram shows proper placement of the contrast medium throughout the joint, cartilage and ligaments. In an abnormal arthrogram, the entire lining of the joint becomes opaque. Abnormal arthrograms may indicate degenerative changes, a cyst or other mass, joint dislocation, ruptures or tears in the ligaments and other conditions.
