Arthrography
Definition
Arthrography allows radiographic examination of a joint after injection of a radioopaque dye, air, or both (double-contrast arthrogram) to outline soft tissue structures and the contour of the joint. The joint is put through its range of motion while a series of radiographs are taken.
Indications for arthography include persistent unexplained joint discomfort or pain. Magnetic resonance imaging of the joint may be used in place of this test.
Purpose
- To outline joint contour and soft tissue structures
- To evaluate persistent unexplained joint discomfort or pain
- To identify acute or chronic tears or other abnormalities of the joint capsule or supporting ligaments of the knee, shoulder, ankle, hips, or wrist.
- To detect internal joint derangements.
- To locate synovial cysts.
- To evaluate damage from recurrent dislocations.
Patient Preparation
- Describe arthrography to the patient and answer any questions he may have. Explain that this test permits examination of a joint.
- Inform the patient that he need not restrict food and fluids.
- Tell the patient who will perform the procedure and where it will take place.
- Explain that the fluoroscope allows the physician to track the contrast medium as it fills the joint space.
- Inform the patient that standard X-ray films will also be taken after diffusion of the contrast medium.
- Tell the patient that, although the joint area will be anesthetized, he may experience a tingling sensation or pressure in the joint when the contrast medium is injected.
- Instruct the patient to remain as still as possible during the procedure, except when following instructions to change position.
- Stress to the patient the importance of his cooperation in assuming various positions because films must be taken as quickly as possible to ensure optimum quality.
- Check the patient’s history to determine if he’s hypersensitive to local anesthetics, iodine, seafood, or dyes used for diagnostics tests.
Procedure
Knee Arthrography
- The knee is cleaned with an antiseptic solution and the area around the puncture site is anesthetized.
- A 2” needle is then inserted into the joint space between the patella and femoral condyle and fluid is separated. The aspirated fluid is usually sent to the laboratory for analysis.
- While the needle is still in place, the aspirating syringe is removed and replaced with a syringe containing dye.
- If fluoroscopic examination demonstrates correct placement of the needle, the dye is injected into the joint space.
- After the needle is removed, the site is rubbed with sterile sponge and the wound may be sealed with collodion.
- The patient is asked to walk a few steps or to move the knee through a range of motion to distribute the dye in the joint space. A film series is quickly take with the knee held in various positions.
- If the films are clean and demonstrate proper dye placement, the knee is bandaged, typically with an elastic bandage.
- Tell the patient to keep the bandage in place for several days and teach him how to rewrap it.
Shoulder Arthrography
- The skin is prepared and local anesthetics are injected subcutaneously just in front of the acromioclavicular joint.
- Additional anesthetic is injected directly onto the head of the humerus.
- The short lumbar puncture needle is inserted until the point is embedded into the joint cartilage.
- The stylet is removed, a syringe of contrast medium is attached and, using fluoroscopic guidance, about 1 ml of dye is injected into the joint space, as the needle is withdrawn slightly.
- If fluoroscopic examination demonstrates correct needle placement, the rest of the dye is injected while the needle is slowly withdrawn and the site is wiped with a sterile sponge.
- A film series is taken quickly to achieve maximum contrats.
Nursing Interventions
- Tell the patient to rest the joint for 6 to 12 hours.
- Wrap the knee in an elastic bandage for several days if a knee arthrography was performed.
- Apply ice to the joint for swelling.
- Give the patient an analgesic.
- Ask the patient to report signs and symptoms of infection.
Precautions
- Know that arthrography is contraindicated during pregnancy and in the patient with active arthritis, joint infection, or previous sensitivity to radiopaque media.
Interpretation
Normal Results
- A knee arthrogram shows a characteristic wedge shaped shadow pointed toward the interior of the joint, indicating a normal medial meniscus.
- A shoulder arthrogram shows the bicipital tendon sheath, redundant inferior joint capsule, and intact subscapular bursa.
Abnormal Results
- Structural abnormalities of the knee commonly suggest tears and lacerations of the meniscus.
- Extrameniscal lesion may suggest osteochondral fractures, cartilaginous abnormalities, synovial abnormalities, cruciate ligament tears, and joint capsule and collateral ligament disruptions.
- Shoulder abnormalities may suggest adhesive capsulitis, bicipital tenosynovitis or rupture, and rotator cuff tears.