Last updated: May 2026. Author: Keith W. Schmidt, MD — Triple Board-Certified Interventional Pain Management Physician, Medical Director of the Neuroscience Institute Pain Program at Ascension Saint Alexius Medical Center, Chair of the ASPN Healthy Longevity & Age-Related Pain Committee.
If your pain has stopped responding to medications, injections, or surgery, you’ve probably heard about “implantable nerve stimulators” — and you’ve probably noticed nobody explains the difference between them. There are three I implant regularly in my Hoffman Estates practice: spinal cord stimulators (SCS), dorsal root ganglion stimulators (DRG), and peripheral nerve stimulators (PNS). They look similar from the outside, but they work differently, target different patients, and produce different results. This is the guide I wish patients had before they walk into my office.
Table of Contents
- What is neuromodulation, in one paragraph
- Spinal Cord Stimulation (SCS)
- DRG Stimulation
- Peripheral Nerve Stimulation (PNS)
- Side-by-side comparison: SCS vs DRG vs PNS
- How I choose between SCS, DRG, and PNS
- The trial period — what to expect
- Recovery timeline
- Insurance and prior authorization in Illinois
- Risks and complications
- Frequently asked questions
- References
What is neuromodulation, in one paragraph
Neuromodulation is a category of pain treatment where a small implanted device delivers mild electrical pulses to specific nerves to interrupt pain signals before your brain perceives them. Think of your nervous system as a network of phone lines from the body to the brain — neuromodulation places a precise “filter” on the line that turns down the pain volume. Unlike medications, neuromodulation is targeted, reversible (the device can be removed), and does not affect the rest of your body. Unlike surgery, it doesn’t change your anatomy. The three flavors I’ll cover here — SCS, DRG, and PNS — differ in where on the nervous system they place that filter.
Spinal Cord Stimulation (SCS)
SCS is the oldest and most-studied form of neuromodulation, FDA-approved since 1989. The device places thin wires (called “leads”) in the epidural space — the protective layer around your spinal cord — and connects them to a small battery, like a pacemaker, implanted under the skin of your lower back or buttock.
Who’s a candidate for SCS
I consider SCS for patients who have broad neuropathic pain affecting the back, legs, or both, after conservative treatments have failed. The strongest indications:
- Failed Back Surgery Syndrome (FBSS) — persistent or recurrent pain after one or more spine surgeries.
- Chronic radiculopathy — sciatica or other nerve-root pain that’s lasted more than 6 months despite injections and physical therapy.
- Diabetic peripheral neuropathy (DPN) — burning, tingling, or aching in both feet or legs from diabetes-related nerve damage. The 2020 SENZA-PDN trial established high-frequency SCS as a meaningful option here.
- Complex Regional Pain Syndrome (CRPS) — when the territory is broader than a single nerve.
- Phantom limb pain — after amputation.
Modern SCS systems use multiple “waveforms” — traditional tonic, high-frequency (10kHz, the Nevro Senza system), burst (Abbott BurstDR), or sub-perception programming. The waveform choice matters: a 2024 randomized comparison in the Journal of Pain Research found responder rates differed substantially by waveform for the same indication.
What the SCS evidence actually shows
The evidence is strongest for FBSS and DPN. The PROMISE trial (FBSS), the SENZA-RCT (10kHz vs traditional), and SENZA-PDN (DPN) are the foundation. Realistic expectations: 50–70% of well-selected patients get at least 50% pain reduction at 12 months, with continued benefit at 5 years in long-term follow-up studies.
DRG Stimulation
DRG stimulation is a more recent technology — FDA-approved in 2016 — that targets a specific anatomical structure called the dorsal root ganglion. The DRG is a cluster of nerve cell bodies located just outside the spinal cord, where the sensory nerves from a specific body region first enter the spinal cord. Think of it as the “switchboard” for sensation from one body region.
Who’s a candidate for DRG
DRG shines for focal pain in a specific anatomical region that an SCS lead can’t easily reach or that responds poorly to traditional SCS coverage:
- CRPS Type I or II in a single limb — the foot, ankle, knee, hand, or wrist. The ACCURATE pivotal trial showed DRG superior to traditional SCS for CRPS at 3 and 12 months.
- Causalgia after a specific nerve injury.
- Post-surgical groin or pelvic pain — after hernia repair, gynecologic surgery, or orthopedic procedures.
- Post-amputation phantom limb pain in a focal distribution.
- Foot or ankle pain that’s neuropathic and refractory.
- Knee pain after total knee replacement when other interventions have failed.
The advantage of DRG over SCS for these indications is precision: DRG can produce pain relief in regions where SCS struggles, like the foot, groin, or hand, with much lower stimulation amplitudes.
What the DRG evidence shows
The ACCURATE trial (Deer et al., 2017) is the foundation — DRG showed 81% treatment success at 3 months for CRPS/causalgia of the lower limb, compared to 56% for SCS. Long-term follow-up at 12 months sustained the advantage. More recent comparative data, including the 2024 BOOST-DRG study, shows that combined SCS + DRG can rescue patients who don’t respond to either alone.
Peripheral Nerve Stimulation (PNS)
PNS is the newest and least-invasive of the three. Instead of placing leads near the spinal cord, PNS places a tiny lead alongside a single peripheral nerve — anywhere from your shoulder to your foot — and stimulates that one nerve. Modern systems (Bioness StimRouter, SPRINT 60-day temporary system, and the newer fully-implantable Nalu and Curonix systems) require no major surgery and often no permanent implant if a 60-day temporary trial provides lasting relief.
Who’s a candidate for PNS
PNS is best for pain in a single nerve’s territory — what we call a “named-nerve” or “mononeuropathy” pattern:
- Post-surgical pain from a single peripheral nerve injury — for example, ilioinguinal nerve after hernia repair, intercostal nerve after thoracotomy, or saphenous nerve after knee replacement.
- Chronic shoulder pain — particularly with suprascapular or axillary nerve targeting.
- Occipital neuralgia — chronic headaches from occipital nerve irritation.
- Chronic low back pain from medial branch nerve dysfunction (a niche but growing application).
- Post-amputation residual limb pain in a focal nerve distribution.
- Knee pain via genicular nerve targeting (overlap with traditional genicular ablation).
What the PNS evidence shows
The strongest evidence is for the 60-day temporary SPRINT system in post-amputation pain and post-surgical knee pain. For permanent PNS, the evidence is more recent but growing: 60–80% of well-selected patients report meaningful relief at 6 and 12 months. The major advantage is that PNS often involves a temporary 60-day implant first; if it works, you may not need a permanent implant at all — the 60-day stimulation appears to “reset” the pain pathway in a meaningful subset of patients.
Side-by-side comparison: SCS vs DRG vs PNS
| Criterion | SCS | DRG | PNS |
|---|---|---|---|
| Where the lead sits | Epidural space, near spinal cord | Near the dorsal root ganglion (just outside spinal cord) | Adjacent to a single peripheral nerve |
| Best for | Broad neuropathic pain (back + legs, both feet) | Focal neuropathic pain in one body region (foot, knee, groin) | Pain in a single named nerve’s territory |
| Lead-of-evidence trial | SENZA, PROMISE, SENZA-PDN | ACCURATE, BOOST-DRG | SPRINT (post-amputation, post-knee) |
| Surgical complexity | Moderate (epidural lead + battery) | Moderate (epidural sheath + battery) | Low (small lead, often no battery for temporary systems) |
| Trial period | 5–10 days, externalized leads | 5–10 days, externalized leads | Immediate response, often 60-day temporary |
| Time to permanent implant | 2–4 weeks after successful trial | 2–4 weeks after successful trial | Sometimes never (60-day temporary may be enough) |
| Body MRI compatibility | Most modern systems: yes (with conditions) | Yes (with conditions) | Varies by system |
| Battery life | 5–10 years (rechargeable) or 3–5 years (primary cell) | 5–10 years (rechargeable) | Often no battery; some systems wireless |
| Reversibility | Fully reversible | Fully reversible | Fully reversible (and often temporary by design) |
How I choose between SCS, DRG, and PNS for a patient
Three questions, in this order:
1. Where is the pain? If it’s broad — both legs, back and legs, both feet — I’m thinking SCS first. If it’s focal — one limb, one body region, one nerve’s territory — I’m thinking DRG or PNS.
2. How focal is the pain? Within “focal,” I divide further. If the pain follows a specific named nerve (the ilioinguinal, the saphenous, the suprascapular), PNS is often the cleanest answer. If the pain is regional but covers multiple peripheral nerves (whole foot, whole hand, whole knee), DRG is usually better because it captures the full territory at the spinal level.
3. What is the diagnosis? CRPS in a single limb? DRG (per the ACCURATE evidence). Diabetic neuropathy in both feet? High-frequency SCS (per SENZA-PDN). Failed back surgery syndrome with leg pain? Traditional or burst SCS. Post-amputation pain? PNS first (often the 60-day temporary), with SCS as backup.
The reality I tell my patients: I am not married to one device family. My patients have implants from Boston Scientific, Abbott, Medtronic, Nevro, and Saluda. I pick the device that fits the patient — not the device my rep wants me to use that month.
The trial period — what to expect
For SCS and DRG, a trial is not optional — it’s mandatory. Here’s how it works for both:
Day of the trial. About a 30-minute outpatient procedure under local anesthesia and light sedation. I place 1–2 leads through a needle, connect them to an external battery on a belt, and dial in a starting program. You go home the same day.
Days 1–7 of the trial. You wear the external battery and adjust the programming using a small remote. The goal is to reproduce activities of daily living — walking, sitting, sleeping — and see whether the device gives you ≥50% pain reduction. Most insurers require at least 50% reduction documented in patient diaries to approve the permanent implant.
End of the trial. Leads come out in a brief office visit. We review your diaries together. If the trial was successful, we schedule the permanent implant — usually 2–4 weeks later, after insurance authorization.
For PNS, the trial is often built into the implant itself. The SPRINT 60-day system is the trial — and for some patients it’s also the entire treatment.
Recovery timeline
- Day of permanent implant: Outpatient procedure, ~1.5–2 hours under sedation. Home the same day.
- Days 1–7: Restricted movement (no bending, lifting >5 lbs, twisting, or reaching overhead). Mostly sleeping, walking, and light activity.
- Weeks 2–6: Gradual return to normal activities. No driving until cleared. No swimming or submerging the implant site.
- Week 6–8: Cleared for full activity, including return to work for most desk-job patients. Manual labor and heavy lifting may take 12 weeks.
- Programming optimization: First few months. We typically have 2–3 follow-up visits to fine-tune the program.
Insurance and prior authorization in Illinois
SCS and DRG are routinely covered by Medicare and most commercial insurers for FDA-approved indications, but every implant requires prior authorization. The standard documentation includes:
- Confirmed diagnosis with imaging (MRI for spine-related causes; EMG/NCS for nerve causes)
- Documentation of failed conservative care (medications, physical therapy, injections)
- Psychological evaluation (mandatory for SCS; insurer-dependent for DRG)
- Successful 5–10 day trial with documented ≥50% pain reduction
In Illinois, the typical prior-authorization timeline runs 2–4 weeks after a successful trial. My team handles all the documentation and communication with your insurer; you handle the trial.
PNS coverage is more variable because it’s newer. We verify coverage on a case-by-case basis before scheduling.
Risks and complications
The major risks are similar across SCS, DRG, and PNS, but rates vary by procedure and indication:
- Infection at the lead site or pocket — 2–5% of cases, lower with modern technique. Most resolve with antibiotics; rare cases require explant.
- Lead migration — the lead moves over time and stops covering the right area. 5–15% over 5 years; addressable with revision.
- Lead fracture — wire breakage. ~3% over device lifetime.
- Loss of effect over time — about 10–20% of SCS patients lose meaningful relief by year 3, often addressable with reprogramming.
- Bleeding at the implant site — usually self-limited.
- CSF leak (epidural placement only) — uncommon but possible with SCS or DRG; managed conservatively.
- Spinal cord injury — extremely rare with modern technique (≤0.1% in published series).
Reversibility is one of the major advantages: if the device doesn’t work or causes complications, it can be explanted, and you return to your pre-implant baseline.
Frequently Asked Questions
Will I feel the device working?
Depends on the system. Traditional tonic SCS produces a “paresthesia” — a tingling or buzzing sensation that overlays the pain. High-frequency 10kHz SCS, burst SCS, and DRG are typically “sub-perception,” meaning you feel pain relief without feeling the stimulation itself. PNS is also typically sub-perception. I’ll match the system to your tolerance for sensation.
Can I get an MRI with a stimulator implanted?
Most modern SCS, DRG, and PNS systems are MRI-conditional, meaning you can have an MRI under specific conditions (1.5T or 3T scanner, specific positioning, manufacturer’s protocol). Older systems may not be MRI-compatible. I’ll confirm the model and conditions for your specific implant.
How long does the battery last?
Rechargeable systems: 5–10 years between battery replacements. Primary-cell (non-rechargeable) systems: 3–5 years. PNS often has no battery (wireless or temporary).
Will it set off airport security?
Yes — every implanted device sets off metal detectors. I provide every patient with an implant card to show TSA. Modern systems are designed to be safe through metal detectors (just announce the implant).
Can I have surgery on other parts of my body after a stimulator implant?
Yes, with coordination. Tell every surgeon and anesthesiologist about your implant. Cautery, electrosurgery, and certain anesthetic techniques have specific protocols around active stimulators.
How soon can I drive after a permanent implant?
Typically 1–2 weeks for SCS and DRG, slightly less for PNS. The constraint is mostly soft-tissue healing and the time the device is set to “off” during the immediate post-op period.
What if the device stops working?
We troubleshoot in three steps: (1) remote interrogation to check the program, (2) reprogramming session with the device rep, (3) imaging to look for lead migration or fracture. Most performance issues are addressable with reprogramming alone. If the device truly fails, revision or explant is straightforward.
Can I have the device removed if I change my mind?
Yes — full removal is straightforward and reverses the implant. This is one of neuromodulation’s defining advantages over surgery: nothing structural in your body has been changed.
References
- Deer TR, et al. “A Prospective, Multicenter, Randomized Trial of Paddle Versus Percutaneous Lead Spinal Cord Stimulation.” Neuromodulation. 2017. (ACCURATE trial — DRG vs SCS for CRPS/causalgia)
- Kapural L, et al. “Comparison of 10-kHz High-Frequency and Traditional Low-Frequency Spinal Cord Stimulation for the Treatment of Chronic Back and Leg Pain.” Anesthesiology. 2015. (SENZA-RCT)
- Petersen EA, et al. “Effect of High-frequency (10-kHz) Spinal Cord Stimulation in Patients With Painful Diabetic Neuropathy.” JAMA Neurology. 2021. (SENZA-PDN)
- Hagedorn JM, George TK, Aiyer R, Schmidt K, Halamka J, D’Souza RS. “Artificial Intelligence and Pain Medicine: An Introduction.” Journal of Pain Research. 2024;17:509–518. PMC10848920
- Sayed D, et al. (including Schmidt KW). “The American Society of Pain and Neuroscience (ASPN) Best Practices and Guidelines for the Interventional Management of Cancer-Associated Pain.” Journal of Pain Research. 2021. PubMed 34295184
- Deer TR, et al. “Comparison of Spinal Cord Stimulation, Dorsal Root Ganglion Stimulation, and the Combination in Patients With Refractory Chronic Back and/or Lower Limb Neuropathic Pain (BOOST-DRG).” Neuromodulation. 2024.
About the Author
Keith W. Schmidt, MD is a triple board-certified interventional pain management physician practicing in Hoffman Estates, Illinois. He is Medical Director of the Neuroscience Institute Pain Program at Ascension Saint Alexius Medical Center, Chair of the American Society of Pain and Neuroscience’s Healthy Longevity & Age-Related Pain Committee, and a co-author on the ASPN Cancer Pain Guidelines (2021) and on “Artificial Intelligence and Pain Medicine: An Introduction” (2024). He completed his Pain Medicine fellowship at Rush University Medical Center and his anesthesiology residency and chief residency at Cook County Health.
If you’d like to discuss whether SCS, DRG, or PNS might fit your case, my office accepts referrals from across the northwest Chicago suburbs. Call (847) 981-3630 or request an appointment online. We see patients from Hoffman Estates, Schaumburg, Arlington Heights, Palatine, Barrington, Rolling Meadows, Elk Grove Village, Inverness, Streamwood, and Des Plaines.