This fact sheet relates to medial branch block injections, a type of back pain relieving injection which is performed at Melbourne Radiology Clinic. The injection relieves pain by delivering local anaesthetic around the nerves responsible for supplying an arthritic or inflamed facet joint with sensation. A CT (Computed Tomography) scan will be used to guide the procedure.
A Medial Branch Block is a test to help your doctor understand whether pain arising from your facet joints can be relieved by numbing the nerves (“medial branches”) that provide them with their sensation. If numbing these nerves results in significant pain relief, then the test is positive.
- There is no specific preparation required.
- We strongly recommend that you bring a responsible person to drive you home afterwards.
Risks of spinal procedures are rare and include:
- Infection: most of these are minor (1-2%), however can be serious (<0.1%) requiring hospital admission, intravenous antibiotics and surgery.
- Bleeding: this is fortunately also rare and common in patients with bleeding disorders and on “blood thinning” medication.
- Nerve damage: from direct needle trauma, or as a consequence of the above mentioned complications.
You will be asked to wear a gown with the selected area of the spine exposed. Spinal injection procedures 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 10-30 seconds.
A fine needle is then passed through the skin and tissues, constantly manipulated under CT guidance until it contacts the nerves that supply the facet joints with their sensation. Local anaesthetic is then administered which numbs these nerves. You will then need to keep a pain diary after the procedure and report back to your referring doctor. If the procedure is deemed a success, you may be eligible for radiofrequency ablation, which permanently destroys the nerves targeted in medial branch block injections.
Important information to tell your doctor prior to treatment
Serious side effects are rare, however if you have an existing condition, this must be discussed with your referring doctor before having treatment. People with local skin or systemic infections are at greater risk of having an infection spreading into the spine after spinal injection treatment. Therefore, if you have a skin infection, which may include wounds, boils or rashes, please tell your doctor or arrange to have the procedure performed at a later date.
Following the procedure
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 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.
Please discuss any medical illnesses with your doctor before booking the recommended procedure.
The radiologist conducting the spinal injection will send your referring doctor a report.
- Please ensure that you make a follow up appointment with your referring doctor or health care provider to discuss your results.
- Please bring to the clinic, any prior scans (eg. X-rays, ultrasounds, MRI, CT) and reports as these will assist the radiologist in assessing your condition.
- If you have any further queries please call Melbourne Radiology Clinic on (03) 9667 1667 – we are only too happy to help.
- Please note that any referral for a scan is valid at Melbourne Radiology Clinic, even if it has been written on a referral form from another radiology provider.
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.