What is a joint injection? A common cause of a painful joint is synovitis (inflammation of the lining of the…Read more
An arthrogram is an image of the inside of the joint obtained by arthrography. This is a procedure carried out by inserting a needle into a joint and injecting contrast medium into the joint cavity using imaging to guide the needle into its correct anatomical position. Guidance may be obtained using fluoroscopy, CT or ultrasound depending on the joint to be examined and the radiologist carrying out the procedure.
An arthrogram image shows structures within the joint cavity; for example, ligaments, cartilage and menisci, as well as the synovial lining of the joint capsule itself. It is usually followed by more detailed scanning of the joint using CT or MRI cross-sectional imaging in multiple anatomical plains. The type of contrast injected will depend on the type of imaging used for post-procedure detailed scanning: iodine-containing contrast and/or air for CT, and gadolinium with saline for MRI.
Limited arthrography is used to confirm correct needle placement within a joint cavity before injecting medication (e.g. steroids) and/or an anaesthetic as part of the diagnostic and therapeutic management of joint pain.
An arthrogram is indicated in the following clinical situations:
There are many other situations in which scans after arthrography may be helpful, and it is often prudent to discuss the clinical problem with the radiologist to obtain advice on the most effective study for the patient’s individual situation.
Generally, the patient should have had at least a previous plain X-ray of the joint and often an ultrasound, CT scan or MRI. These should be available to the radiologist for assessment before arthrography.
Arthrography (like any test) should only be carried out when the additional information obtained has the potential to alter the treatment or provide additional prognostic information when compared with a non-arthrographic or alternate study (e.g. ultrasound for rotator cuff tear).
Reflex sympathetic dystrophy: Any procedure or minor injury may reactivate or aggravate the symptoms. The Reflex Sympathetic Dystrophy Syndrome Association guidelines recommend the avoidance of all types of even minor procedures on the affected limb.
Avascular necrosis of bones adjacent to the affected joint: Anecdotal reports suggest that arthrography aggravates the pain of avascular necrosis.
Anticoagulation: There is no evidence to suggest that arthrography is contraindicated for patients on anticoagulation within the normal therapeutic range. However, the risk of intra-articular or periarticular bleeding in deep joints; for example, the hip, is increased in patients on anticoagulants. This is can be minimised with the use of experienced operator technique and small needles.
Arthrography is a very safe procedure and complications are unusual.
The most serious complication is an infection of the joint. This is usually caused by organisms from the patient’s skin being transferred into the joint and for this reason the procedure should not be carried out if there is broken or infected skin overlying the joint.
The risk of infection is not precisely known, but the best available information suggests that it is in the order of 1 in 40,000.
Occasionally, people may be allergic to the contrast medium that is injected and this most commonly results in a rash, but may be more serious (see InsideRadiology: Complications of ICCM). The risk of minor reaction (e.g. hives) has been reported at 1:2000. More serious reactions appear to be very rare.
A transient synovitis can occur with the use of iodine-containing contrast medium. For example, an increase in shoulder pain may be noted lasting 24–48 hours after an arthrogram of the shoulder. It is not associated with other systemic symptoms and settles spontaneously.
Complications of the MRI contrast medium (gadolinium chelate) have not been reported, probably because of the very small amounts used in arthrography.
Increasing joint pain not settling in 24–48 hours especially when associated with systemic symptoms, such as fever, raise the possibility of joint infection (septic arthritis). Patients need to be clinically assessed urgently, and they may require possible joint aspiration, surgical lavage and antibiotic therapy.
Patients on anticoagulants who develop increasing joint pain may have a haemarthrosis. Although symptoms may resolve with rest, aspiration of the haemarthrosis may be required.
Direct visualization of the intrinsic structures of the joint by arthroscopy carried out by an orthopaedic surgeon is the most common alternative test.
Page last modified on 20/10/2017.
RANZCR® is not aware that any person intends to act or rely upon the opinions, advices or information contained in this publication or of the manner in which it might be possible to do so. It issues no invitation to any person to act or rely upon such opinions, advices or information or any of them and it accepts no responsibility for any of them.
RANZCR® intends by this statement to exclude liability for any such opinions, advices or information. The content of this publication is not intended as a substitute for medical advice. It is designed to support, not replace, the relationship that exists between a patient and his/her doctor. Some of the tests and procedures included in this publication may not be available at all radiology providers.
RANZCR® recommends that any specific questions regarding any procedure be discussed with a person's family doctor or medical specialist. Whilst every effort is made to ensure the accuracy of the information contained in this publication, RANZCR®, its Board, officers and employees assume no responsibility for its content, use, or interpretation. Each person should rely on their own inquires before making decisions that touch their own interests.