Joint X-ray with Contrast Dye
What is joint X-ray with contrast dye?
Joint X-ray with contrast dye is used to examine a joint, such as the knee or hip, when standard X-rays are not adequate. A series of X-rays is taken with the joint in various positions after contrast dye is placed in the joint. The doctor may use fluoroscopy, CT, or MR imaging to better visualize the joint.
While joint X-ray is most commonly used to examine the knee and shoulder joints, it may also be used to examine other joints, such as the wrist, ankle, hip, or elbow.
Anatomy of the shoulder
The shoulder is made up of several components, including the following:
Bones. These are the collarbone (clavicle), the shoulder blade (scapula), and the upper arm bone (humerus).
Joints. These facilitate movement, including the acromioclavicular (AC) joint (where the clavicle meets the acromion) and the shoulder joint (glenohumeral joint) that facilitates forward, circular, and backward movement of the shoulder.
Ligament. A type of tough, elastic connective tissue that surrounds the joint to give support and limits the joint's movement. The ligaments of the shoulder include the joint capsule (a group of ligaments that connect the humerus to the socket of the shoulder joint on the scapula to stabilize the shoulder and keep it from dislocating), ligaments that attach the clavicle to the acromion, and ligaments that connect the clavicle to the scapula by attaching to the coracoid process.
Acromion. This is the roof (highest point) of the shoulder that is formed by a part of the scapula.
Tendon. A type of tough connective tissue that connects muscles to bones and helps to control movement of the joint.
Muscle. A strong, contractile tissue that helps support and rotate the shoulder in many directions.
Rotator cuff. Composed of tendons, the rotator cuff (and associated muscles) holds the ball of the glenohumeral joint at the top of the upper arm bone (humerus).
Bursa. A fluid-filled sac located between bones, ligaments, or other adjacent structures that helps cushion joints. In the shoulder, the bursa is located between the rotator cuff muscle layer and the outer layer of large, bulky muscles and keeps the rotator cuff from rubbing on the shoulder joint.
Anatomy of the knee
The knee is a vulnerable joint that bears a great deal of stress from everyday activities, such as lifting and kneeling, and from high-impact activities such as jogging and aerobics.
The following parts form the knee:
Tibia. This is the shin bone or larger bone of the lower leg.
Femur. This is the thighbone or upper leg bone.
Patella. This is the kneecap.
Each bone end is covered with a layer of cartilage that absorbs shock and protects the knee. Basically, the knee is two long leg bones held together by muscles, ligaments, and tendons.
There are two main groups of muscles involved in the knee, including the quadriceps muscles (located on the front of the thighs), which straighten the legs, and the hamstring muscles (located on the back of the thighs), which bend the leg at the knee.
Tendons are tough cords of tissue that connect muscles to bones. Ligaments are elastic bands of tissue that connect bone to bone. Some ligaments of the knee provide stability and protection of the joints, while other ligaments limit forward and backward movement of the tibia (shin bone).
Why might I need a joint X-ray with contrast?
A joint X-ray with contrast may be done on a joint when there has been persistent and unexplained pain, discomfort, and/or dysfunction in the joint. Other reasons to do this test may include:
To identify abnormalities (for example, acute and chronic tears) in the soft tissues of the joint, such as ligaments, cartilage, and joint capsules
To evaluate damage from recurrent dislocations of the joint
To locate synovial cysts
There may be other reasons for your doctor to recommend joint X-ray with contrast.
What are the risks of joint X-ray with contrast?
You may want to ask your doctor about the amount of radiation used during the procedure and the risks related to your particular situation. It is a good idea to keep a record of your radiation exposure, such as previous scans and other types of X-rays, so that you can inform your doctor. Risks associated with radiation exposure may be related to the cumulative number of X-ray exams and/or treatments over a long period of time.
People who are allergic to or sensitive to medications, contrast dyes, local anesthesia, iodine, or latex should tell their doctor.
Some potential risks of X-ray include, but are not limited to, the following:
Infection at the puncture site where the contrast dye is injected
Allergic reaction to the contrast dye; however, such a reaction is rare because the substance is not injected into a vein
Joint X-ray is not recommended for people with active arthritis or with joint infections.
If you are pregnant or think you may be, tell your doctor. Radiation exposure during pregnancy may lead to birth defects. If it is necessary for you to have a joint X-ray, special precautions will be made to minimize the radiation exposure to the fetus.
There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your doctor prior to the procedure.
How do I prepare for joint X-ray with contrast?
Your doctor will explain the procedure to you and ask if you have questions.
You may be asked to sign a consent form that gives your permission to do the procedure. Read the form carefully and ask questions if something is not clear.
Generally, there is no special restriction on diet or activity prior to the procedure.
Tell your doctor if you are sensitive to or are allergic to any medications, latex, tape, anesthetic agents (local and general), contrast dyes, and iodine.
Tell your doctor of all medications (prescribed and over-the-counter) and herbal supplements that you are taking.
Tell your doctor if you have a history of bleeding disorders or if you are taking any anticoagulant (blood-thinning) medications, aspirin, or other medications that affect blood clotting. It may be necessary for you to stop these medications prior to the procedure.
If you are pregnant or suspect that you are pregnant, tell your doctor.
Based on your medical condition, your doctor may request other specific preparation.
What happens during joint X-ray with contrast?
Joint X-ray may be done on an outpatient basis or as part of your stay in the hospital. Procedures may vary depending on your condition and your doctor's practices.
Generally, joint X-ray follows this process:
You will be asked to remove any clothing, jewelry, or other objects that may interfere with the scan.
If you are asked to remove clothing, you will be given a gown to wear.
You will be positioned on the exam table in the procedure room.
X-rays of the joint may be taken prior to the injection of the contrast dye for comparison with the images obtained after the substance is injected.
The skin around the joint to be examined will be covered with sterile drapes and cleaned with an antiseptic solution.
The area around the joint will be numbed by injection of a local anesthetic. You will feel a numbing sensation.
If there is fluid in the joint, this fluid will be aspirated (removed) with a syringe.
The contrast dye will be injected into the joint. After this injection, you may be asked to move the joint so that the contrast dye can be distributed evenly throughout the joint. You may be asked to exercise the joint. In the case of knee X-ray, you may be asked to walk around for a few minutes.
Once the contrast dye has been distributed through the joint, multiple X-rays will be made with the joint in various positions. In some cases, a special frame or traction may be used to spread out the joint for a wider view of the joint. Items such as pillows or sandbags may be used to help position the joint. You may have an MRI, or less commonly, a CT, after the arthrogram has been performed to obtain full evaluation of the joint.
While the joint X-ray procedure itself causes no pain, having to hold the joint still in certain position for the procedure might cause some discomfort or pain, particularly in the case of a recent injury or invasive procedure such as surgery. The technologist will use all possible comfort measures and complete the procedure as quickly as possible to minimize any discomfort or pain.
What happens after joint X-ray with contrast?
Your doctor will give you specific instructions about movement of the joint, pain medication, care of the affected joint, symptoms to watch for, and any activity restrictions.
You may be asked to rest the joint for several hours after the procedure.
Some mild swelling may be noted in or around the joint. Your doctor may suggest that you apply ice to the joint if swelling occurs. If swelling continues or increases after a day or two, tell your doctor.
Take a pain reliever for soreness as recommended by your doctor. Aspirin or certain other pain medications may increase the chance of bleeding. Be sure to take only recommended medications.
After a knee X-ray, the affected knee may be wrapped with an elastic bandage for several days. You will be shown how to apply the bandage and remove it for bathing and dressing.
You may notice some clicking or cracking noises with movement of the joint for a few days after the procedure. This is normal, and should resolve within a few days.
Tell your doctor if any of the following occur:
Redness, swelling, bleeding, or other drainage from the injection site
Increased pain around the injection site
You may resume your normal diet unless your doctor advises you differently.
Your doctor may give you additional or alternate instructions after the procedure, depending on your particular situation.