By Dr. Tory McJunkin, MD | Bladder Centers of America | Phoenix, AZ
Introduction
If you’re living with overactive bladder (OAB), urinary urgency incontinence, or fecal incontinence that hasn’t responded to medications or lifestyle changes, sacral neuromodulation (SNM) may be the breakthrough you’ve been waiting for. Two FDA-approved devices dominate this space: Axonics Modulation and InterStim (by Medtronic). As a urologist in Phoenix, AZ who implants both systems, I want to give you a transparent, physician-authored comparison so you can make the most informed decision possible.
Sacral neuromodulation works by delivering mild electrical impulses to the sacral nerves that control bladder and bowel function. Think of it as a “pacemaker” for your bladder. Both Axonics and InterStim devices accomplish this goal — but they differ in important ways that matter to real patients.
What Is Sacral Neuromodulation?
Sacral neuromodulation (SNM) is a minimally invasive, reversible procedure used to treat:
- Overactive bladder (OAB) — urgency, frequency, urge incontinence
- Non-obstructive urinary retention — inability to empty the bladder fully
- Fecal incontinence — loss of bowel control
- Urgency-frequency syndrome
The procedure involves placing a small lead (wire) near the S3 sacral nerve root and connecting it to a small implanted pulse generator (IPG) — the “device.” Patients typically undergo a trial phase first to confirm effectiveness before permanent implantation.
At Bladder Centers of America in Phoenix, AZ, we perform both the trial and permanent implant procedures with same-day or next-day return home.
Axonics Modulation vs. InterStim: Head-to-Head Comparison
| Feature | Axonics r-SNM | Medtronic InterStim X/Micro |
|---|---|---|
| FDA Approval | 2019 (OAB, urinary retention, FI) | 1997 (OAB, urinary retention); 2011 (FI) |
| Device Size | 6.0 cc (smallest rechargeable SNM) | InterStim X: 9.2 cc; Micro: 3.8 cc |
| Battery Life | 15+ years (rechargeable) | Micro: ~15 yrs non-rechargeable; X: rechargeable |
| MRI Compatibility | Full-body 1.5T & 3T | Full-body 3T compatible (InterStim X) |
| Clinical Evidence | ARTISAN-SNM: 97% response | 30+ years clinical data |
Who Is a Good Candidate for SNM?
You may be a candidate for sacral neuromodulation if:
- You have OAB, urge incontinence, or fecal incontinence
- You’ve tried at least one medication without adequate relief
- Lifestyle modifications alone have not controlled your symptoms
- You are not a good candidate for Botox injections, or Botox has failed
FAQ: Axonics vs InterStim
Q: Is the Axonics modulation device better than InterStim?
Neither device is universally “better” — they have different strengths. Axonics offers 15+ year battery life; InterStim Micro offers an ultra-small non-rechargeable option.
Q: Will I feel the sacral neuromodulation stimulation?
Most patients feel a mild tingling or pulsing sensation. Over time, many patients stop noticing the sensation at all.
Q: Can I have an MRI with an SNM device?
Yes — both Axonics and InterStim X are full-body MRI compatible at 1.5T and 3T.
Q: How long does the SNM trial phase last?
The trial phase typically lasts 7 to 14 days with an external stimulator.
Q: Does sacral neuromodulation work for men with OAB?
Absolutely. Both Axonics and InterStim are FDA-approved for men and show comparable outcomes to women.
Ready to Find Out If SNM Is Right for You?
The best way to know if Axonics or InterStim is right for you is a consultation with an experienced SNM implanting physician. At Bladder Centers of America in Phoenix, AZ, we’ve helped hundreds of patients regain control of their bladder and bowel.
📞 Call us today or visit bladdercenter.com to schedule your evaluation. Most insurance plans accepted.