Arthrogram (Joint X-Ray)
An arthrogram is a test using X-rays to obtain a series of pictures of a joint after a contrast material (such as a dye, water, air, or a combination of these) has been injected into the joint. This allows your doctor to see the soft tissue structures of your joint, such as tendons, ligaments, muscles, cartilage, and your joint capsule. These structures are not seen on a plain X-ray without contrast material. A special type of X-ray, called fluoroscopy, is used to take pictures of the joint.
An arthrogram is used to check a joint to find out what is causing your symptoms or problem with your joint. An arthrogram may be more useful than a regular X-ray because it shows the surface of soft tissues lining the joint as well as the joint bones. A regular X-ray only shows the bones of the joint. This test can be done on your hip, knee, ankle, shoulder, elbow, wrist, or jaw (temporomandibular joint).
Other tests, such as magnetic resonance imaging (MRI) and computed tomography (CT), give different information about a joint. They may be used with an arthrogram or when an arthrogram does not give a clear picture of the joint.
Why It Is Done
An arthrogram is used to find the cause of ongoing, unexplained joint pain, swelling, or abnormal movement of your joint. It may be done alone, before, or as part of other tests, such as MRI, CT, or arthroscopy.
An arthrogram is used to:
- Find problems in your joint capsule, ligaments, cartilage (including tears, degeneration, or disease), and the bones in the joint. In your shoulder, it may be used to help find problems such as rotator cuff tears.
- Find abnormal growths or fluid-filled cysts.
- Confirm that a needle has been placed correctly in your joint before joint fluid analysis, a test in which a sample of joint fluid is removed with a thin needle.
- Check needle placement before a painkilling injection, such as a corticosteroid injection.
How To Prepare
Tell your doctor before your arthrogram if you:
- Are or might be pregnant.
- Are allergic to any type of contrast material.
- Are allergic to iodine. The dye used for an arthrogram may contain iodine.
- Are allergic to any medicines, including anesthetics.
- Have ever had a serious allergic reaction (anaphylaxis) from any substance, such as a bee sting or eating shellfish.
- Have asthma.
- Have bleeding problems or are taking blood-thinning medicines.
- Have arthritis that is bothering you at the time of your test.
- Have a known infection in or around your joint. The dye may make your infection worse.
- Have diabetes or take metformin (Glucophage) for your diabetes.
You will be asked to sign a consent form that says you understand the risks of the test and agree to have it done.
Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form( What is a PDF document? ).
How It Is Done
An arthrogram is usually done by a doctor who specializes in interpreting X-rays (radiologist).
You will be asked to remove any jewelry or metal objects from the joint area. You will then sit or lie down with your joint under an X-ray viewer (fluoroscope) that is hooked to a video screen that can show X-ray pictures. The skin over your joint is cleaned with a special soap and draped with sterile towels. A local anesthetic is used to numb the skin and tissues over the joint.
A needle is put into your joint area. Joint fluid may be removed so that more contrast material (such as dye or air) can be put into the joint. A sample of joint fluid may be sent to a lab to be looked at under a microscope. The fluoroscope shows that the needle is placed correctly in your joint. The dye or air is then put through the needle into your joint. The joint may be injected with both dye and air (double-contrast arthrogram). The needle is then removed.
You may be asked to move your joint around to help the dye or air spread inside your joint. Pictures from the fluoroscope show if the dye has filled your entire joint. Hold as still as possible while the X-rays are being taken unless your doctor tells you to move your joint through its entire range of motion. The X-rays need to be taken quickly, before the dye spreads to other tissues around your joint.
If you are having a CT scan or MRI after an arthrogram, a small amount of a medicine called epinephrine may be mixed with the dye to stop the dye from spreading into other tissues.
An arthrogram usually takes about 30 to 60 minutes.
After the arthrogram, rest your joint for about 12 hours. Do not do any strenuous activity for 1 to 2 days. Use ice for any swelling and use pain medicine for any pain. If a bandage or wrap is put on your joint following an arthrogram, you will be told how long to use it.
How It Feels
You will feel a prick and sting when the anesthetic is given. You may feel tingling, pressure, pain, or fullness in your joint as the dye is put in.
The X-ray table may feel hard and the room may be cool.
You may have some mild pain, tenderness, and swelling in your joint after the test. Ice packs and nonprescription pain relievers, used as the package directs, may help you feel more comfortable. You may also hear a grating, clicking, or cracking sound when you move your joint. This is normal and goes away in about 24 hours. If you have ongoing pain, tenderness, or swelling of the joint, tell your doctor.
You can have a few problems from an arthrogram, such as:
- Joint pain for more than 1 or 2 days.
- An allergic reaction to the dye.
- Damage to the structures inside your joint or bleeding in the joint. But this is very rare because the needle that is used is small.
- Infection in the joint.
There is always a slight risk of damage to cells or tissue from being exposed to any radiation, including the low levels of radiation used for this test. But the risk of damage from the X-rays is usually very low compared with the potential benefits of the test.
An arthrogram is a test using X-rays to obtain a series of pictures of a joint after a contrast material (such as a dye, water, air, or a combination of these) has been injected into the joint. The radiologist may discuss the initial results with you after he or she reviews all the pictures. A detailed report will be available to your doctor in a few days.
The joint capsule, the sac containing joint fluid, is normal. The cartilage and other structures of the joint are normal.
The cartilage is worn down (degeneration) or there is a tear in the cartilage cushion of the joint.
There is a tear in the ligaments or tendons of the joint. The tear may be partial or complete. If a rotator cuff tear in the shoulder is present, the dye leaks from the tear.
The joint capsule is enlarged or has ruptured. A joint cyst is present.
Abnormal material is present in the joint. This could be a tumor, extra growth of joint tissues, or pieces of bone or cartilage.
After your doctor has seen the condition of your joint area, further treatment with medicine, physical therapy, or surgery may be recommended.
What Affects the Test
Reasons you may not be able to have the test or why the results may not be helpful include:
- If you can't hold still during the test. The pictures may not be clear.
- If there is a large amount of fluid in your joint. This may affect the spread of the dye and the pictures.
What To Think About
- Magnetic resonance image (MRI) and computed tomography (CT) give different information about a joint. These tests may be used with an arthrogram or when an arthrogram does not give a clear picture. Also, an MRI or arthroscopy may be used before or in addition to an arthrogram to check your joint problem.
- An arthrogram may be done if other tests, such as MRI, are not available. It also may be done to help your doctor decide whether arthroscopic surgery is needed.
- An arthrogram is usually not done during pregnancy.