A spinal cord stimulator trial is a test, not a small version of the treatment. Temporary leads are placed, you live with the stimulation for a short period, and the question being answered is narrow: does this change your pain enough, and in the right way, to justify implanting a device. It exists because stimulation cannot be predicted from a scan or an examination — the only reliable way to find out whether your nervous system responds is to try it and measure what happens.
What the trial is screening for
Patient selection for spinal cord stimulation has to account for two separate things: whether the pain problem is an appropriate indication, and whether patient factors — psychological state, smoking, opioid use — predict a poor response. A trial complements that clinical screening rather than replacing it.1
Consensus guidance also recommends that a formal process to elicit patient information and gauge acceptance of the chronic pain state, within a multidisciplinary framework, be considered before proceeding to stimulation.1 In practice that means the conversation before the trial matters as much as the trial itself.
What the numbers actually look like
A single institution reported outcomes for 505 consecutive stimulator trials. The population matters when reading these figures: mean age was 67.5 years and 64.2% of the patients were female.2
In that series, 86.1% of patients achieved trial success and 77.0% went on to permanent implantation.2 The gap between those two numbers is worth sitting with — a successful trial and a decision to implant are not the same event, and some people who respond still choose not to proceed.
Response is not uniform across diagnoses
In the same series, patients with diabetic neuropathy had the highest trial success rate at 83.3%, while patients living with CRPS had the lowest at 67.6%.2 That is not a reason to rule out a trial for CRPS, also called reflex sympathetic dystrophy or RSD. It is a reason to go in with calibrated expectations, and to have the rest of the plan — including ketamine therapy where appropriate — already under discussion rather than held in reserve.
Benefit is durable for most, but not all
At follow-up ranging from 3 to 34 months, 76.6% of implanted patients maintained significant improvement.2 The overall explant rate was 14.1%, with loss of efficacy the leading cause, and lead migration and infection were the most frequent complications.2
Tobacco use, depression, chronic opioid use, and falls after implantation were statistically significant predictors of explantation.2 Three of those four are modifiable before a trial is ever scheduled, which is an argument for treating the run-up to the trial as part of the treatment.
Opioid use and what the trial can change
In that series, opioid use decreased in 58.9% of patients.2 That is a meaningful figure for anyone hoping to reduce their medication burden, but it is an outcome to work toward with a prescriber, not a switch the device flips. How that reduction is managed is covered under opioid stewardship.
Questions worth asking before you consent
A trial that is not clearly defined in advance produces an ambiguous result, and an ambiguous result is hard to act on. Before the leads go in, it is reasonable to ask:
- What threshold are we using to call this a success, and how will it be measured?
- Besides pain intensity, what function are we tracking — walking tolerance, standing time, sleep?
- What happens if I respond partly? Is the answer more programming, a different target, or a different treatment altogether?
- Which of my own risk factors — smoking, mood, medication, fall history — should be addressed first?
If a partial response redirects the plan, the alternatives are the same image-guided options used elsewhere in the practice, including epidural steroid injection, nerve blocks, and peripheral nerve stimulation.
Frequently asked questions
What counts as a successful spinal cord stimulator trial?
A predefined threshold of improvement agreed before the trial starts, measured against how you actually functioned during it rather than recalled afterward. The procedure and what it involves are described on the spinal cord stimulation page.
If my trial succeeds, will the benefit last?
Often, though not always. In a series of 505 consecutive trials, 76.6% of implanted patients still had significant improvement at follow-up between 3 and 34 months, while the overall explant rate was 14.1%, most often for loss of efficacy. Alternatives if benefit fades are on the pain treatments page.
Does having CRPS make a stimulator trial pointless?
No. CRPS showed the lowest trial success rate in that series at 67.6%, which is still a majority, but it argues for calibrated expectations and a layered plan. See CRPS and RSD treatment.
Can anything I do beforehand improve the odds?
Possibly. Tobacco use, depression, chronic opioid use and post-implant falls were each significant predictors of the device later being removed. Addressing them is worth raising early, including through counseling for chronic pain.
What happens if the trial does not work?
It has still answered the question, and it prevents an implant that would not have helped. The plan then moves to other targets, which may include nerve blocks or peripheral nerve stimulation.
To discuss whether a stimulator trial fits your situation, request an appointment, call (314) 481-5000, or text (314) 886-5902.
Sources
- Shanthanna H, Eldabe S, Provenzano DA, et al. Evidence-based consensus guidelines on patient selection and trial stimulation for spinal cord stimulation therapy for chronic non-cancer pain. Regional Anesthesia & Pain Medicine. 2023;48(6):273. doi:10.1136/rapm-2022-104097. PMC10370290
- Gheith R, Wortmann M, Najjar M, Oliver C, Whitlow B, Raterman B, Shackelford KR. Real-World Outcomes of Spinal Cord Stimulation: A Consecutive Institutional Experience with 505 Trials, Trial-to-Implant Ratio, Long-Term Efficacy, and Explantation Risk Factors. Journal of Pain Research. 2025;18:6381–6395. doi:10.2147/JPR.S552361. PMC12672166
Dr. Gurpreet Singh Padda, MD, MBA, MHP
