Sacroiliac Joint Injection.

This fact sheet relates to sacroiliac joint injections, a type of back pain relieving injection which is performed at Melbourne Radiology Clinic.This pain management treatment usually stops pain stemming from an arthritic or inflamed sacroiliac joint by delivering anti-inflammatory medication into the affected area. A CT (Computed Tomography) scan will be used to guide the procedure.

Fact Sheets | Interventional Radiology | Back & Spinal Pain Injections

Sacroiliac Joint Injection.


Sacroiliac joints are at the lower part of the spine, where the sacral spine segments (the part of the spine below the lumbar spine) connect with the pelvic bones flanking the sacrum, known as the iliac bones. The joint is complex, with the lowermost part of the joint typically targeted for injection of cortisone.

Sacroiliac joint pain is often vague and variable, such that it may be difficult to determine whether these joints are causing a patient’s pain or not. As clinical tests for sacroiliac joint pain may be unreliable, frequently a trial injection is performed to see if the pain is alleviated. Other treatment options following a response to a cortisone injection include destroying the nerves which supply the joint with radiofrequency ablation (RFA) as a longer lasting option.


01There is no specific preparation required.
02Bring along a support person / driver

We also strongly recommend that you bring a responsible person to drive you home afterwards.


Please discuss any medical illnesses with your doctor before booking the recommended procedure.


Risks of sacroiliac joint injections are rare and include:

most of these are minor (<1%), however can be serious (<0.1%) requiring hospital admission, intravenous antibiotics and surgery.


this is fortunately also rare and slightly common in patients with bleeding disorders and on “blood thinning” medication.


CT Guided
Sacroiliac Joint Injection

You will be asked to wear a gown with the selected area of the spine exposed. Sacroiliac joint injections  are completed with you lying face down in a CT scanner. We will ensure that you are as comfortable as possible.

A series of planning images are performed, with the area of needle entry planned on the computer terminal and then marked on your skin. The radiologist will then clean your skin with an antiseptic wash and inject local anaesthetic into the injection site. This results in a stinging sensation which is temporary until the skin becomes numb, usually taking 10 seconds.

A fine needle is then passed through the skin and tissues, constantly manipulated under CT guidance until it enters the sacroiliac joint. A mixture of cortisone and local anaesthetic are injected which decrease inflammation and therefore pain.

Some discomfort will be felt for a short time whilst the cortisone-anaesthetic mixtures distends the joint. The local anaesthetic will then anaesthetise the joint. The effects of the treatment vary and it is difficult to predict the duration of pain relief until the procedure is performed. In some people, pain is relieved for months, others years and still for others it produces no relief at all. In the case of the latter, your doctor may recommend an alternative treatment, which may include radiofrequency ablation (RAF).

Following your procedure & recovery

At most, you will feel some minor discomfort in the back. As local anaesthetic has been injected into the spine most patients will be pain free. Patients are able to walk freely after the procedure and are observed in the clinic for 5-10 minutes. Following this, you may be discharged if you are feeling well.

You should not drive for the rest of the day. The following day you may return to work and gradually increase your activities.

Results &

Your Images and Report

One of Melbourne Radiology Clinic’s specialist radiologists, a medical doctor specialising in the interpretation of medical images for the purposes of providing a diagnosis, will then review the images and provide a formal written report. If medically urgent, or you have an appointment immediately after the scan to be seen by your doctor or health care provider, Melbourne Radiology Clinic will have your results ready without delay. Otherwise, the report will be received by your doctor or health care provider within the next 24 hours.

Follow-up Appointment

Please ensure that you make a follow up appointment with your referring doctor or health care provider to discuss your results.

Your referring doctor or health care provider is the most appropriate person to explain to you the results of the scans and for this reason, we do not release the results directly to you.


Previous Scans & Reports

Please bring to the clinic any prior scans (eg. X-rays, ultrasounds, MRI, CT) and reports as these will assist our radiologist in assessing your condition.

Any Referral Request Accepted

Please note that any referral for a scan is valid at Melbourne Radiology Clinic, even if it has been written or printed on a referral form or stationery supplied by another radiology provider.

If you have any further queries about your appointment please call Melbourne Radiology Clinic on (03) 9667 1667  – we are always only too happy to help.

Appointment Time

Whilst every effort is made to keep your appointment time, the special needs of complex cases, elderly and frail patients can cause unexpected delays. Your consideration and patience in these circumstances is appreciated.

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