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Below is a video of an RF ablation procedure we found on YouTube. Not for the faint of heart!
RF Ablation of Lumbar Spinal Nerves by Dr. Anthony Gueiffrida
Radio frequency ablation (RFA) of nerves can be used to reduce pain. In the case of spinal arthritis, there is no surgery that can repair damage, as there is for herniated disks or stenosis. By frying the nerves that carry the pain signal, pain relief is possible, but there are no guarantees. And the relief is temporary, as the nerves grow back after a year or so.
Spinal arthritis can be caused by repetitive strain, such as phyical labor. Poor posture, like slumping while sitting, or trying to sleep on a long plane ride are known contributers to the problem. Running, especally on hard surfaces, can exacerbate the condition. Now it's time to go into first person mode... Guilty as charged! There are at least a couple dozen homes in New Jersey where I carried all of the cement blocks that were used to build the basement. It's a good summer gig if you want to look ripped when you return to college in the fall, but I can no longer recommend it. And running outdoors in Tucson, there are no comfy trails like there are in Oregon, the dirt is as hard as pavement. I only run occasionally these days, but I used to put in 15 miles a week back in the day, it is an effective way to manage your weight. Did I mention I have 2,000,000 miles on a major airline?
Before you are eligible for RFA, your insurance company might ask you to go through some practice runs. The doctor uses applies numbing agent (Lidocaine) to the nerves so see if pain is reduced. In the case of a certain insurance provider, if you want to be eligible for RF nerve ablation, you will have attest that your pain was reduced by 80% during this test. When the doctor asks for a pain level before the procedure, 1 through 10, with 10 being Spanish Inquisiton torture, you'd better say a number of 5 or higher. It pays to plan ahead....
If you are creeped out by having large (and hot) needles jammed into your back, you can get a prescription for a party drug to improve your mood. Advice: don't overdue this, the follow-on affect of the drug can be worse than the pain of the needles. As much as you desire to be "tripping balls", you need to be coherent.
Below are a mix of some photos from the actual office visit and stuff we borrowed from the world-wide web. Boston Scienific makes much of the equipment that is used in this industry, including the "G4 Radiofrequency Generator". If you live in suburban Boston you have may driven by one or more of their buildings, their current headquarters is in Marlborough. The G4 (fourth generation) Radio Frequency Generator's manual is available here. A quick perusal shows that their definbition of "radio frequency is very low frequency by microwave standards. The ablation is doen at 480 kHz, with a power capoability up to 50 watts. The instrument monitors the impedance your body presents and makes adjustments as needed. Here, we are NOT talking about (L'/C')^0.5 impedance, but the real impedance in ohms that your tissue presents.
To complete the circuit, there is a ground pad that is attached to the patient with conductive gel. It acts much like what is used in electric chair executions (or not used, like in the 1999 movie the Green MIle).
On the hot side of the system, a cannula is used to pierce the skin, and an electrode is pushed through it to reach the targetted nerve. Here is an image of a US patent 9770290, where an electrode pushed through a cannula, and expands to increase the conductive surface. The cannula also offers a direct path to inject numbing agents to the nerve prior to ablation.
Three nerves are ablated on each side of the spin, in two separate procedures. The G4 generator only has four channels, otherwise maybe they could all be fried at the same time. Before ablation occurs, sensory simulation is used to verify electrode placement. This is why you need to stay awake during the procedure. In one case, the simulation resulted in patient's leg kicking unconrollably. To which the doctor advised the tech to "move the electrode to the left". If the wrong nerve is ablated, there can be some numbness in the legs. Checking the G4 manual, the stimulator pulse can be between 2 and 200 Hz, with pulse width up tro 3 ms. Obviously this is done at a low power (non-ablating) level.
Here are the RF cables with electrodes after the procedure, being sterilized. Don't worry, the electrodes are disposable.
Here the disposable electrodes in a sharps bin. Medical waste has to be carefuly disposed of, you don't want to expose sanitary disposal technicians to any of this mess.
After sitting in the recovery area for a few minutes to make sure you are not goiing to faint, on your way out, a piano player with a fake book soothes your troubled mind.
It takes up to two weeks for the nerves to die, then you should notice some improvement, with reduce pain you may find you have an increase in range of motion. As mentioned, the effects of RFA are temporary. One personal goal is to increase spinal flexibility before the effect wears off. But that carries the risk of further angering the arthritic joints. Time will tell!