Neurostimulators

Nerve stimulation uses electrical energy to block specific nerves from sending pain signals to the brain. Delivering tiny electrical impulses to the nerve changes how it behaves and how often it fires. There are three types of neurostimulators doctors recommend to treat pudendal neuralgia that is not resolved to return to normal life by conservative treatments. Remember, all procedures and implants have risks no matter how minor.

A Brief Overview of Neurostimulators:

Peripheral Nerve Stimulators (PNS) - A PNS is a neurostimulator that a doctor place the lead (electrode) next a peripheral nerves. Except for the brain and spinal cord, all nerves are peripheral. The pudendal nerve is a peripheral nerve. All batteries are external and attached to the body with an adhesive or a wearable. There are four manufacturers.

StimRouter
Nalu
Curonix Stimwave
Sprint

Sacral Nerve Stimulators (SNS) - A SNS can help to restore normal bladder or bowel function. It can also help pudendal neuralgia pain as many people with PN suffer incontinence. We need to interview a doctor to confirm if SNS is ever used to treat PN exclusively in patients who do not suffer incontinence. All batteries are surgically implanted after 7-trial period required by the FDA. There are two manufacturers:

Axonics (two types that vary in siz: R20 and F15.
Interstim (Medtronics)

Dorsal Root Ganglion stimulator (DRG) - The DRG is designed to manage difficult-to-treat chronic pain in specific areas of the lower body, such as the foot, knee, hip or groin. The battery is internal and surgically implanted. There's currently one U.S. company that manufactures a Dorsal Root Ganglion stimulator:

Proclaim™ DRG (Abbott)

Below is more detailed information on each stimulator.

In addition, we have dedicated a full submenu to each

one listed here.

1. Peripheral Nerve Stimulators – PNS (4 Companies)

Medicare, work insurance companies and state Medicaids generally do not cover PNS because there

are no clinical studies since condition is rare so no profit for medical device companies.

A. Stimrouter® (Bioventus)
B. Curonix Stimwave Freedom (Stimwave Dufunct, StimQ Disocontinued)

C. Nalu™ (Nalu Medical)
D. Sprint® (SPR Therapeutics) – Implanted for only 30-60 days

Batteries are External for all PNS. (rechargeable like a cell phone).
Only thin lead is implanted Internally next to the pudendal nerve.

A peripheral nerve is any nerve that lies outside your brain and spinal cord. The pudendal nerve derives from the sacral nerves S2, S3, and S4. PNS is a minimally invasive outpatient procedure in which a small lead with electrodes is placed at beginning of pudendal nerve. Direct

stimulation of the pudendal nerve may stimulate

more sensory nerve fibers than SNS.Aftercare and

adherence to post-implant activity restrictions-avoid

use of the extremes of hip flexion and extension for

four weeks-lead to the absence of lead migration.

See Each PNS page for MRI Compatibilty

A. StimRouter

(Bioventus,) uses an adhesive to keep its device in place on the body. It can be submerged in water like Nalu and Curonix. Its battery is smaller than Curonix Stimwave and Nalu.

Warning Note: No trial period. We are concerned that Bioventus considers a positive Diagnostic Anesthetic Pudendal Nerve Block as its trial. The only objective of the block, one of the five Nantes Criteria in 2007, is to diagnosis pudendal neuralgia.

The block has nothing to do with PNS devices. Bioventus is skipping a true medica trial unlike its competitors. This translates to only one visit by the StimRouter sales representative instead of two which means they can implant many more PNS that their peers.

We encourage Bioventus to follow the bench standard of a true trial period to test and ensure the safety and efficacy of their product immediately.

B. Curonix Stimwave Freedom - has trial period

Uses "wearables" that close uses Velcro instead of adhesives to to hold in place its transmitter assembly. We hope to get feedback from pudendal neuralgia patients if they find this approach or adhesives works better to keep the device in place in the area of the pudendal nerve.

C. Nalu - has up to a 14-day trial period

Uses adhesive and a therapy disk that sits in a clear holder. The disk can communicate from the base to the receiver and back (2-way). Its therapy desk (battery) is larger than Stimrouter but there may be things about it, how it fits your body, that you may prefer. You receive two so one is always charging. The Nalu has more choices for power and pulse rates. Nalu has a trial period and requires a positive Diagnostic Anesthetic Pudendal Nerve Block. This is the best indicator that a person will do well with a neurostimualtor. Nalu uses an adhesive to adhere the battery to your body the same as Stimrouther and Sprint PNS.

D. SPRINT PNS - Is a temporary device; there has no trial period

Has no permanent implants and is less stable than the others. It can fall out or the adhesive can give way more easily. Stays for 60 days only. Asserts short-term stimulation for long-term relief 50%. You cannot submerge in water.

2. Sacral Nerve Stimulators – SNS (2 Companies)

SNS Batteries are Internally Surgically Implanted (unlike PNS) and must be replaced every 4 to 7 years. 2

There is a 7-Day Trial Period per the FDA before the permanent lead and battery are surgically implanted.in the treatment of and was designed for interstitial cystitis/bladder pain syndrome (IC/BPS)

A. Axonics F15™; Axonics R20™ (Axonics, Inc.)

B. InterStim™ (Medtronic)

Sacral nerve stimulation (SNS) works with a tined lead

electrode that is placed through sacral plexus S3,

Sacral nerve stimulation (SNS) can effectively treat
1. Interstitial cystitis/bladder pain syndrome (IC/BPS

2. Fecal incontinence, overactive bladder (including

the frequent, strong, andsudden urge to go) -- restore

normal bladder or bowel function. SNS addresses

the communication problem between the bladder/bowel,

and the brain that maybe causing symptoms.

Medicare, work insurance companies and state Medicaids generally DO cover SNS for IC/Bladder

pain and fecal incontinence because clinical studies conclude SNS successfully treats these conditions.

3. Dorsal Root Ganglion Stimulator – DRG (1 Company)

A. Proclaim™ DRG (Abbott)

Battery is Permanently Internally Implanted and must be replaced every 6.5 years. 1

Proclaim has a 7-Day Trial Period per the FDA.

"DRG stimulation therapy works by stimulating dorsal root ganglia (DRGs). These are structures along the spinal column made up of densely populated sensory nerves, and they act like traffic lights, regulating signals and sensations that travel through nerve fibers along the spinal column to the brain.

Because the spinal column has a number of different DRGs, each of which is associated with different areas of the body, DRG stimulation therapy can target the DRG that is associated with the specific area of the body where a patient experiences pain. In this way, DRG therapy has the unique ability to help manage pain in targeted parts of the body where pain occurs and is especially helpful for patients who live with isolated chronic pain in the lower parts of the body."

PNA was able to find ONE study about one 35-year-old woman with PN. This would not be near enough to convince FDA to approve DRG for pudendal neuralgia. Study is listed below. 4

Some doctors will claim that the DRG is the best neurostimulator for treatment of pudendal neuralgia pain, bu non have done a sound medical clinical study. We believe doctors say this because they are already familiar with DRG.

Doctors are very weary to remove broken DRG lead fragments

Dorsal root ganglions (DRGs) emerge from the dorsal root bundles of the spinal nerve’s dorsal column. DRGs carry sensory messages from various receptors at peripheral nerves to the spine then to the brain for a pain response. Dorsal Root Ganglion/Nerve root exiting the spinal cord. DRG Proclaim™ is indicated to manage Moderate to severe chronic intractable in the lower limbs in adult patients with Types I and II CRPS pain in specific areas of the lower body, such as the foot, knee.

Through research and talking to pudendal neuralia members on the numerous Facebook Pudendal Neuralgia Group, PNA has determined that the vast majority of pain management doctors recommend DRG before any other type of neuromodulation. We are researching to determine why this is the case as the DRG is not designed to treat specific peripheral nerve pain such as pudendal neuralgia.

Magnetic Resonance Imaging Compatibility (MRIs)

The current Proclaim IPG is MRI-conditional using 50 cm leads for head and extremity MRI using prescribed parameters when placed below the T10 level.230 Placing the device into “MRI mode” restricts energy transmission into the IPG and potential damage to the BluetoothTM technology.

The Procedure:

Implantation of a Dorsal Root Ganglion stimulator is a two-step process that involves first implanting the stimulator, and then a pulse generator to power it. To implant the stimulator, an incision is made in the patient's back; the wires with electrodes on the end are fed through and positioned on the spinal cord. Exact placement depends on the area of pain.

To implant the pulse generator, an incision is made in the buttocks or abdomen, and the generator is placed between layers of skin and muscle. An extension wire is run from the spine to whichever area the generator is placed in. Incisions are closed with either staples or sutures. The procedure takes 2 tp 4 hours, and the patient usually goes home on the same day.

The DRG leads are not implanted inside the spinal coloumn Some doctors use DRGS to treat pudendal neuralgia pain. After trial is approved, the battery (look for size) is surgically, permanently implanted under skin in lower back.

Pudendal Neuralgia Alliance is going to post more detailed information soon. We support this option to treat pudendal neuralgia because it is the only bold treatment other than decompression surgery and is reversible after conservative methods fail, even after years. We need both of these procedures, but we must research, follow science, listen to doctors, patients, and our intuition. This is where second opinions providers who are not connected professionally can play a critical role.

Currently the FDA does not require doctors to observe and train under a highly experienced doctor nor does the FDA require doctors then to implant stimulators under the supervision of a highly experienced doctors as is the case with all other specialties and procedures we are aware of. The only requirement is a training with a speaker and a presentation, much like PowerPoint. Doctors can practice on cadavers if they choose. This FDA approval of no training on living patients is unacceptable and needs to need as soon as possible. There will be challenges because the faster a doctor can start to implant a medical device, the faster the doctor, the company, and the hospital can starting making money. There are many documentaries and books and this serious problem.

Many pain management doctors feel if they are experienced at implants in the shoulder or knee, they know enough to implant a neurostimulator next to the pudendal nerve without any additional training under an experienced physician. It is not required by the FDA.

It does not seem to follow best practices for patient safety and device efficacy and safety to avoid training specifically to implant peripheral neurostimulator next to the pudendal nerve because of its unique location and the fact that it carries both sensory and motor signals. An error due to the implant being a doctor's first, second, or even tenth time without ever training on a living person could risk feeling and incontinence. The introducer needle is 13 gauge (large). The smaller the number, the bigger the needle. For example, doctors use a 22 gauge needle for a transgluteal pudendal nerve block.

Generally doctors train under an experienced doctor to learn a new procedure and observe and are observed many times conducting the procedure before administering it on their own.

We are not doctors, but we hope the pain management community reconsiders and requires doctors to train on living people before implanting a PNS on their own on their first pudendal neuralgia patient or at least will open discussions about it at hospital meetings and conventions.

Twilight Sleep option during large gauge introducer until lead is in place to test for efficacy

We've only been able to talk to a few people who have had PNS implanted by doctors new working on the PN. They all said the experience of the introducer needle was extremely painful, but didn't say anything because they were desperate for the neurostimulator to hopefully significantly reduce their PN pain. One cried and the doctor ignored her.

We've talked to about eight PNS reps. They all felt the pain warranted twilight sleep until the lead was in place. None had ever heard of or observed an implant for PN. This means they will also have no experience.

The most common combination of medications used to induce Twilight Sleep intravenously are:
Fentanyl and Midazolam.

We hope doctors will talk to us about using twilight sleep until the lead is in place to test and THEN wake up the patient to find the exact position for the lead to be most effective. Patients need pain management during painful procedures. For example, most patients who receive pelvic floor Botox injections get light sedation (not general anesthesia with intubation) during the procedure. They are unconscious and do not feel the pain

SPRINT PNS was the only video I could find so far of surgeons demonstrating the insertion of an introducer into

a real person. Go to 7:30 min of the 24:24 min video. It looks painful. Link below.

https://www.youtube.com/watch?v=fzeGH5VSpyU&t=445s

Under "Real Stories" the first is of a young woman, 29, who had a PNS implanted and the experienced was extremely painful and failed. We suspect it was a failure because she was his first pudendal neuralgia living patient.

Ultrasound vs. Fluoroscopy

"There are no large studies comparing ultrasound and fluoroscopic guidance for the placement of PNS. Nerve blocks for peripheral nerves have been described using both ultrasound and fluoroscopy. Key factors to consider include the size of the lead, need for entrance at a distance from the target nerve to allow for appropriate lead placement, planning placement of the lead(s) parallel or crossing in relation to the nerve and tunneling needed. Ultrasound has the advantage of direct visualization of the nerve with a dynamic view of lead placement, enabling accurate determination of the distance between the PNS lead(s) and the target nerve." 1

Ultrasound also does not release any radiation.

1 https://www.dovepress.com/evidence-based-clinical-guidelines-from-the-american-society-of-pain-a-peer-reviewed-fulltext-article-JPR

2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4158824/

3 https://braininitiative.nih.gov/sites/default/files/documents/proclaim_drg_device_information_508c.pdfhttps://www.pennstatehealth.org/services-treatments/neurosurgery/dorsal-root-ganglion-stimulation-therapy (DRG)

4 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9994636/

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Pudendal Neuralgia Alliance

contact@pudendalneuralgiaalliance.org

Paid for by volunteer until 501c3 status granted by IRS

Neurostimulators

Magnetic Resonance Imaging Compatibility (MRIs)

Ultrasound vs. Fluoroscopy

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