The medical term 'neurotomy' refers to any type of medical procedure intending to modify the function of a nerve, and a sacro-iliac radiofrequency neurotomy ('RFN') procedure is generally used to relieve pain in the lower section of the back and the buttocks arising from the sacro-iliac joint.
The technique uses radio waves to generate heat (at about 85C), which is then applied via a thin needle directly to a very small area of nerve tissue. The procedure does not completely destroy the nerve, but it does prevent it from transmitting pain signals to the spinal cord and the brain.
In many cases the technique gives much longer-term pain relief that alternatives such as nerve blocks and other injectable treatments.
The procedure is generally preceded by the application of a diagnostic nerve or joint block, which determines whether or not the specific nerve is responsible for the pain. If the nerve block results in significant reduction in pain, a neurotomy may be recommended as a longer lasting treatment.
Radiofrequency neurotomy is also known by many other terms, such as 'radiofrequency ablation', 'radiofrequency denervation', 'radiofrequency lesioning', 'radiofrequency rhizolysis' or radiofrequency rhizotomy'. These all describe the same procedure.
After the procedure, the nerve tissue very slowly regenerates in a process that takes anywhere between six months and two years. If the pain returns (and it sometimes does not), the neurotomy may need to be repeated. Around 60% of people who undergo this procedure report pain relief lasting for a year or more.
- Facet joint syndrome.
- Lower back / buttock pain.
- Previous spinal surgery.
- Arthritis (specifically osteoarthritis of the sacro-iliac joint) .
You should avoid undergoing any other medical procedures, such as for example dental treatment or a colonoscopy, within 48 hours (before or after) of the procedure.
Do not eat or drink anything in the 6 hours immediately before the procedure (although any medication can continue to be taken with small sips of water). Medication for diabetes should not be taken until after the procedure.
If you are taking any medication containing aspirin, you should stop taking this at least 11 days before the procedure.
Please also let us know ahead of the procedure if…
- You are taking any antibiotics.
- You have a pacemaker or defibrillator.
- You are ill (in which case we may need to postpone the procedure).
You should also not drive yourself to or from the appointment.
You are asked to lie face down on a special fluoroscope (real time X-ray) table and an IV line is put in place in your arm or hand to supply a light anaesthetic. You need not stay awake during this procedure.
The injection site is then cleaned and numbed with a local anaesthetic and a thin needle is inserted at the injection site and then guided (use the fluoroscope image) into position.
At this point a local anaesthetic is injected via the needle to numb the nerve and, when this has taken effect, radio waves heat the needle which then blocks the nerve from sending pain signals.
After the procedure you are able to return home. There is no restriction on day-to-day activities, although, as advised above, due to the sedation you should not drive a vehicle for at least 24 hours after the procedure (so it is a good idea to have someone drive you to and from the appointment). You should also avoid any strenuous activity for a few days.
In some cases, there may be some pain or discomfort (sometimes a sensation similar to sunburn) and/or bruising to the skin at the injection site, which may last for about a week.
A sacro-iliac joint radiofrequency neurotomy is a relatively low risk procedure, however all medical treatment comes with some level of risk. Possible complications may include…
- Pain at injection site.
- Allergic reaction to anaesthetic and / or contrast dye.
If you experience severe pain or weakness, or your temperature is over 38C, you should let us know urgently or visit the nearest emergency department.