Radiofrequency Neurotomy is a technique for applying heat very precisely to the region of a specific nerve while avoiding heat injury to other nerves and structures in the area. While many people refer to this technique as “burning” the nerve or “cutting” the nerve, or “killing” the nerve, that is not precisely what happens. The nerve is heated enough to damage some of its signal transmission components. After the neurotomy, the nerve will go about repairing itself, a process that takes 6-18 months. During that time period, pain being transmitted by those nerves is relieved.
The technique can be used on some nerves in the body which transmit pain signals but are not crucial for proper functioning. Examples include nerves to the sacroiliac joint and to the facet joints in the spine.
Typically, before doing radiofrequency neurotomy, your doctor will do a series of diagnostic anesthetic blocks to the nerves in question, to prove that they are transmitting the pain signals that are bothering you.
HOW IS IT DONE?
Conscious sedation is utilized to make the procedure more comfortable. This means you will have an IV placed before the procedure is done and through that IV you will be administered sedative medication during the procedure. It will be enough to relax you but you will still be awake so you can answer the doctor’s questions during the procedure. Because of the sedation, you will not be able to have any food on the day of the procedure until after the procedure is completed.
For the procedure you will be placed on your stomach on the procedure table. In the procedure room there will be monitoring devices checking your heart rate, blood pressure and blood oxygen level and there will be a fluoroscopic X-ray machine which the doctor will use to guide the needles used during the procedure. The procedure will start with the doctor cleaning off your skin with an antiseptic soap. Then the fluoroscope will be used to find the needle entry sites in the skin. These will be marked with a pen and then the doctor will anesthetize the skin and muscles with an anesthetic injection similar to the Novocain a dentist uses. At the same time, you will be getting some sedative through the IV to relax you.
Using a fluoroscope, the doctor will then place the needles, called RF canula, near the nerves to be heated. This part can be a little uncomfortable and that is why you get the IV sedative. Once the canula are near the nerves, the doctor will stimulate the nerves with a little electricity to make sure the canula are right next to the nerves we want to heat and far away from any nerves we do not want to injure. There are two types of electrical stimulation, a high frequency and a low frequency. The high frequency feels like a buzzing, tingling, or pressure and the doctor will ask you to identify the moment you start to feel it. The low frequency actually makes the muscles near your spine contract. The doctor will turn the stimulus up to a certain threshold level and if there are no strong contractions in muscles other than the paraspinals, the canula is in a perfect position. If other muscles are contracting strongly, then the canula will be repositioned until those contractions go away. Once the canula is in the optimal position, the doctor will inject lots of anesthetic and wait 3 minutes. Each nerve will be heated for 60-120 seconds and heating should not be uncomfortable. If it is uncomfortable, the procedure will be interrupted and a little more anesthetic will need to be injected before proceeding. At the end, a little corticosteroid will be injected to reduce any post-procedure inflammation around the nerve.
After the procedure, you will be observed by the procedure nurses for about ½ hour to make sure the sedative is wearing off appropriately. They may also ice your back to reduce any muscular soreness post procedure.
RISKS AND SIDE EFFECTS
When the procedure is done as described, the risks are minimal. To date, we have never had an instance of unintentional damage to a nerve that wasn’t the target of the procedure. Every patient experiences some local muscle tenderness for a few days. Approximately 1/15 patients undergoing lumbar radiofrequency neurotomy for facet pain experience a significant increase in their usual pain, which can last 3-12 days and ends abruptly. There is a small risk of infection with any needle procedure. There is a very small risk of being left with a temporary dysesthetic sensation on the skin above the procedure area. The feeling is similar to minor sunburn.
When radiofrequency is done to treat facet pain in the neck, the side effect profile is a little different. When the C4-C7 nerves are treated, 50% of the patients should expect increased pain for up to two weeks. You may have numbness on the skin of the neck that may persist for several months. When the C3 nerve is treated, many patients will experience “ataxia,” a non-disabling feeling of unsteadiness that can last for two weeks.
In rare instances, such as severe cancer pain, nerves critical to function might be lesioned intentionally and, in that case, specific more severe side effects would be expected. Ask your doctor what those expected side effects would likely be.
POST RADIO FREQUENCY NEUROTOMY INSTRUCTIONS
Normal activity can be resumed the day after the procedure. Due to the conscious sedation, no driving or operating dangerous machinery on the day of the procedure. For local muscle tenderness, ice the procedure area 15 minutes 3-4 times per day. If you experience an amplification of your usual pain post procedure, contact your doctor and ask if you can use a little higher dose of your usual pain medication for 3-10 days.
Pre and Post Instructions
- Electrodiagnostic Medicine
- Electromyography/Nerve Conductions Studies
- Cervical Epidural Cortisone Injections
- Lumbar Epidural Cortisone Injections
- Facet Joint or Nerve Injections
- Radiofrequency Neurotomy
- General Post-operative Guidelines for Spinal Surgery
- Spinal Cord Stimulation