Radiofrequency ablation minimally invasive procedure for neuroma
When conservative treatments for neuromas fail, the next step is often to perform a minimally invasive procedure. As we have discussed, there are multiple minimally invasive procedures that may alleviate the need for open surgical intervention.
One of the most common forms of minimally invasive neuroma procedures that we do is radiofrequency ablation (RFA). This FDA approved procedure entails applying heat to the nerve in order to kill it. This causes it to cease function and no longer caused pain without actually removing the neuroma through open surgery.
Who is a candidate for radiofrequency ablation procedures?
Radiofrequency ablation for neuromas is not a first line of treatment. It is reserved for when patients have failed more conservative treatments first. For a list and description of conservative treatments for neuromas, please see our page on nonsurgical neuroma treatments by clicking here.
What is a radiofrequency ablation?
Ablation procedures have been performed in medicine for many years. The word ablation in this context means to remove or destroy tissue in an area in the body. Radiofrequency ablation is defined as removing or destroying tissue by the means of the application of a radiofrequency which creates heat. Radiofrequency energy, in the form of radio waves, are delivered to a pinpoint area in the body by the means of a thin metal probe.
The tip of the radiofrequency probe vibrates microscopically at a specific frequency in order to create heat. In this case, the tip of the catheter is heated to 90°C (194°F). For reference, water boils that 100°C (212°F). The radiofrequency ablation machine that we use has a thermometer to constantly monitor the temperature at the tip of the probe in real time. This ensures that the area does not exceed the desired temperature.
At this extreme temperature, the heat breaks down proteins in the nerve tissue of the neuroma. This prevents sensation from traveling through the nerve to be perceived by the brain. If there is no perceived sensation, theoretically there will be no pain.
How hot does the radiofrequency probe get?
What to expect during a radiofrequency ablation procedure for neuroma
From years of experience, we have figured out how to achieve the best results using radiofrequency ablation for neuroma, while allowing for the least amount of discomfort and pain for our patients.
How is a radio frequency ablation procedure for neuroma done?
Radiofrequency ablation procedures are done in our office. We do not require one to go to a surgical center nor hospital. After we saw the great success rate of radiofrequency ablation procedures, we decided to purchase the medical device that is needed for this procedure. Although the initial investment in this equipment was high, it makes it very convenient for our patients, as well as more affordable, by doing this procedure in our office.
The first step in performing this procedure is to localize the neuroma using diagnostic ultrasound. We visualize the nerve and neuroma under ultrasound and make multiple marks on the foot with a skin marker indicating where the anatomy is.
After we identify the exact positioning of the nerve and neuroma, the next step is to perform local anesthesia. Using a very small needle, we perform an injection in the skin over the nerve. This injection is very small and often patients tell us that there is little to no pain. This allows us to subsequently introduce the larger cannula through the skin into the foot with no pain at the level of the skin.
Cannula insertion
The next step is the insertion of a cannula into the foot. A cannula is a hollow metal needle that will allow us to introduce the radiofrequency ablation probe through it, and into the area of the neuroma. In order to ease the cannula through the soft tissues, the hole down the center of it is filled with a thin, sharp closed bore needle. The narrow radiofrequency probe will replace this needle and go through the cannula to reach the neuroma.
The intermetatarsal ligament
The anatomy of the foot is such that there is a ligament that connects the two adjacent metatarsal bones. This ligament resides just above the neuroma. It is this anatomy that allows us to place the cannula and probe in the exact correct position. Once we feel that we penetrate through this thick ligament, we know we are at the right depth to find the neuroma.
Diagnostic ultrasound to confirm placement
Once we have pierced the intermetatarsal ligament, we again use diagnostic ultrasound to confirm that we are in the perfect place. One of the future steps that will be performed is to stimulate the nerve and ask the patient to identify when they feel the mild tingling sensations. For this reason, we are not able to perform complete local anesthesia, otherwise the patient would not feel stimulation. It is important for the patient to let us know when they feel the tingling to ensure that the radiofrequency probe is close enough to the nerve in order for it to work.
Although patients do feel the cannula entering the foot, crossing through the ligament, and approaching the nerve, most patients describe this pain as mild to moderate.
Nerve stimulation
After we have placed the cannula, we remove the closed bore needle inside of it. It is then replaced with the radiofrequency ablation probe. The probe is wired to the radiofrequency machine. Prior to ablating the nerve, it is critical that we confirm that the probe is in the exact correct position. In order to do this, we introduce electrical stimulation through the probe at a very low level. We ask the patient to let us know when they feel the mild tingling caused by this electrical stimulation.
We slowly increase the energy in the electrical stimulation until the patient tells us that they first feel it. By observing the amount of energy required in order for the patient to feel it, we determine how close to the nerve we are. If it requires too much energy in order for the patient to feel it, we readjust the position of the probe in order to try to get closer to the nerve. Once the patient feels the electrical stimulation at a low threshold of energy, we know we are in the perfect place.
The perfect location for performing the ablation
As you can see from the many steps above, including mapping the skin with ultrasound guidance, feeling the anatomy as we cross the intermetatarsal ligament, performing electrical stimulation with patient interaction, and many years of experience, we can be sure that the probe is in the perfect place to achieve our desired outcome.
After we are sure that the probe is in the correct location, then we perform one more electrical stimulation using a different setting for motor nerve stimulation. This allows us to be sure that we are not ablating any muscle or motor nerve tissue.
Local anesthesia
At this time, we are now ready to perform an additional injection for local anesthesia. We remove the probe from inside the cannula. Since the cannula is hollow, it allows us to inject anesthesia right through it. This eliminates the need or any further additional injections. We inject a combination of long-acting and short-acting anesthesia through the cannula. Most patients describe this as a mild to moderate burning sensation. We are introducing anesthesia right on the nerve.
Is radiofrequency ablation for neuroma painful?
Most patients consider this the worst part of the procedure; however, it is not that painful, but rather just a burning sensation. Through years of experience, we have determined that by taking our time and not rushing this part of the procedure, we can reduce the pain and discomfort drastically.
Wait until it is numb
At this stage, we take a short break and wait for the anesthesia to take effect and make sure that the nerve is completely numb. We use this time to our advantage to discuss with the patient what to expect after the procedure both right away, and in the long-term. I will describe this in additional paragraphs below.
Start the ablation procedure
After the local anesthesia is injected and has time to work, we then reinsert the radiofrequency probe into the cannula. We slowly increase the temperature of the probe while asking the patient if they feel any pain. If they feel any pain, we immediately turn off the heat and allow the local some more time to work, or occasionally add more local anesthesia.
Once we are able to slowly increase the temperature of the probe without any pain, we are able to perform the ablation procedure. Once the probe has reached 90°C (194°F), we start the 90 second timer. After the 90 second timer has completed, we move the probe and reposition the cannula in a slightly different direction.
Three ablations
After repositioning the cannula slightly toward the back of the foot, we add some more anesthesia. At this stage, the area is numb and patients rarely feel any more discomfort with this anesthesia injection. We then perform a second ablation procedure in this new direction, more proximally. After 90 seconds of ablating, we then reposition the cannula more distally than the first two ablations. After adding more anesthesia in the new location, we then ablate this new location for 90 seconds again.
In total, we perform three ablation procedures, in three slightly different locations of the foot. This includes proximal to the neuroma, distal to the neuroma and at the neuroma.
After we perform three ablation procedures at the three different locations, we are now done. We remove the cannula and the radiofrequency probe. Patients leave the office with a simple Band-Aid. There is no need for surgical dressings. Patients are instructed to return to their normal shoes, which we recommend that they wear sneakers. We recommend patient do not take mass transit such as trains or buses to get home after the procedure. This is in order to alleviate the amount of postprocedure walking necessary.
What to expect after a radiofrequency ablation procedure for neuroma
We advise patients that the anesthesia will wear off in between 6 and 24 hours. When the anesthesia has worn off, most patients describe the pain as mild burning sensations. We instruct patients to take Tylenol as needed for pain. We instruct patients to elevate the foot and use ice to reduce inflammation. Patients are able to return to mild activity the next morning. Many commute to work as normal on the first day postoperatively. Most patients feel better using a comfortable shoe or sneaker for 1-3 days after the procedure. There is no need for surgical shoes or braces.
Some patients will notice bruising and swelling at the procedure site. This is completely normal and expected. This only lasts a few days to a few weeks. The procedural pain may last a couple of days to a couple of weeks. Most patients describe the postoperative recovery in a similar fashion. They report that the original neuroma pain has been replaced by procedural pain. The typical nerve pain with numbness, tingling and shooting is replaced by a dull aching sensation. Rarely, the pain may be more severe in the area from the procedure but only lasts a week or two.
Follow-up after radiofrequency ablation for neuroma
We instruct patients to return to our office two months after their procedure. At this visit, the patient will inform us on how they are feeling. This may range from completely pain-free, to decreased pain, to the pain has stayed exactly the same. On rare occasions, patients have informed us that there is more pain than before the procedure.
Repeat radiofrequency ablation procedure for neuroma, second time
About 75% of people achieve enough relief that they do not require additional procedures. If they are completely pain-free, we advise them to only follow-up if necessary. If the pain has decreased but is still present, we advise them to return in another two months to determine if they require another radiofrequency ablation procedure or not.
The other 25% of people who are still experiencing pain, undergo a second radiofrequency ablation procedure on this follow-up visit. When we make this follow-up visit, we allocate an hour of our time to allow time for a repeat of the procedure when necessary. The repeat radiofrequency ablation procedure is performed in exactly the same manner as described above for the first one.
Third radiofrequency ablation procedure for neuroma.
A majority of people achieve relief from one or two radiofrequency ablation procedures and do not require a third. For the small number of people that are still experiencing pain after the first and second radiofrequency ablation procedure, will sometimes perform a third procedure. It is very rare that we will perform any more than three procedures. Although I have performed a fourth and fifth procedure on a very small number of patients, if the procedure fails after three, I usually instruct them to move on to a more invasive procedure. These more invasive procedures will be described on another page of this website.
What is the success rate of radiofrequency ablation procedures for neuroma?
About 75% of people that have radiofrequency ablation procedure for neuroma achieve enough relief of pain and they do not require additional treatments. Many patients have complete 100% resolution of the pain, and some have significant enough resolution that they do not require additional treatments.
Of the 25% that go on to repeat the radiofrequency ablation procedure two or three times, an additional 80-90% of them have enough relief of symptoms that they do not need additional treatments. The remaining small percent of people go on to additional, usually more invasive, procedures.
What to expect long-term after radiofrequency ablation procedures
After the pain has resolved and a few months have elapsed from your procedure, you can expect to have some numbness in the area. A majority of patients report numbness in the adjacent toes, just distal to where the neuroma was. Virtually all of these patients report that this numbness is acceptable, and minor compared to the pain that they had before the procedure. In my experience, I have had no patients complain that the numbness bothered them a lot, nor regretted performing this procedure due to numbness.
Only a very small number of patients, about three that I can recall, have returned with a complaint of neuroma pain in the same spot after a year or more after the radiofrequency ablation procedure was performed. Many have returned with other neuromas that have become painful at a different location in the foot, but not for the same neuroma. Interestingly, many articles in the literature have stated that radiofrequency ablation procedure can be a temporary cure with recurrence. Personally, I have not seen this.
What are the possible complications that can occur after radiofrequency ablation procedure for neuroma
Although I have never seen an infection after radiofrequency ablation procedure, it is a possible complication. It is possible to track bacteria through the skin when performing any invasive procedure such as an injection. Obviously, we use sterile technique by wiping the skin with alcohol prior to performing any injection or procedure.
Radiofrequency ablation procedure for neuroma is a very safe procedure. In about two decades of performing these procedures, only two patients that I know of, have experienced complications and were not satisfied with the procedure. Both of these patients reported increased pain at the neuroma site that was different than the actual neuroma pain. One of these patients went on to have open neuroma surgery, performed by me, which resolved her issues completely. The second patient did not come back for follow-up. I sincerely hope that they sought other treatment and are now pain-free.
Why do you think radiofrequency ablation for neuroma procedure sometimes fails?
A small percentage of patients go on to need additional procedures after radioactive ablation procedure fails. In theory, this procedure should kill the nerve and work 100% of the time if there is no longer sensation traveling to the brain. My theory on why this procedure sometimes fails is that the brain still perceives pain even after the nerve has been killed. For example, some patients experience a syndrome called phantom limb pain. In that case, patient still experience pain in the leg and even after the leg has been amputated. The brain still perceives pain where there is no longer any nerves, nor the leg completely. After years of experiencing pain, the brain is tricked into feeling continued pain that no longer exists. I believe this is why patients still experienced pain after the nerve has been killed the radiofrequency ablation.
Is radiofrequency ablation procedure covered by insurance?
Radiofrequency ablation procedure for neuroma is a covered service by virtually all insurance companies. In my experience, I have not seen any insurances that do not reimbursed for the cost. With that said, we are out of network with all insurances which may result in some out-of-pocket costs. A majority of PPO insurances will reimburse 100% of our fees. Please see the “insurance and financial” page of our website. We have expertly trained staff in our office that we will gladly discuss financial obligations prior to any procedure.
Why is radiofrequency ablation not a very common procedure offered?
Many doctors who treat neuromas do not perform radiofrequency ablation procedures. There are many reasons for this, both clinical and economic. Clinically, this is a relatively new procedure in podiatry. Although ablation procedures have been performed for many years, it is relatively new to perform them in the foot for neuroma. For example, ablation has been used in the heart for arrhythmias and in the spine for chronic pain syndromes for many decades.
The first studies in radiofrequency ablation for neuroma in the foot were performed in the early 2000’s. This is when we started performing these procedures in our office. When I was a resident, this procedure did not exist and was not taught. I received instruction on how to perform this procedure and I saw how successful it was. Throughout the years, I have adapted my procedure in many ways in order to increase the success rate. Many doctors have not undergone training nor have the experience that we have.
Considering economic variables, this procedure requires a significant level of monetary investment in order to perform it. The machine itself is very expensive as well as the consumable used for the procedure. Each procedure requires a sterile pack that is specific for the radiofrequency machine. This sterile pack includes a cannula, a closed bore needle that fits into the cannula and the radiofrequency probe with wire. This pack of consumables is for one patient use only and is disposable.
Unfortunately, the cost of the sterile consumable pack is often as much, or more and then some insurances will pay for the procedure. Obviously, this impacts whether or not the doctor will perform the procedure. In our office, we do not have contracts with insurance companies and are out of network. This ensures that we are reimbursed in excess of our cost for the supplies necessary for the procedure.
Summary
Radiofrequency ablation procedure for neuroma is an excellent alternative to performing open neuroma surgery when conservative therapy fails. This extremely safe procedure allows for a very high success rate, and a very low complication rate. It is conveniently performed in our office and requires little to no down time postoperatively. It is cost effective and covered by most insurances. We have some of the most experience in the world in performing this procedure having done literally many hundreds. We invite you to come in for a consultation to discuss this procedure with our doctors.