Spinal Cord Stimulation in St. Louis

A thin wire, called a lead, carries electrical contacts. It goes in the epidural space, just outside the spinal cord. It hooks up to a small generator placed under the skin. The device sends mild electrical pulses. They change how pain signals are handled on their way to the brain. It does not treat the first injury. It changes the message the nervous system sends about it.

Nobody gets a permanent implant without first doing a trial. Temporary leads go in percutaneously (through the skin with a needle). You wear them for several days and go back to your normal day. The trial answers the only question that matters. Does this cut your pain enough, and steadily enough, to justify an implant? Patients who do not get a clear response in the trial do not go forward.

The best candidates have nerve pain that has not responded to injections, medicine, or surgery. Common reasons to use it include lasting radicular leg pain, pain after spine surgery, and complex regional pain syndrome. We usually consider it after less invasive options such as epidural steroid injection have been tried.

Both the trial and the implant are outpatient procedures. You go home the same day. Modern systems can be programmed. So the pattern can be adjusted over time as your pain changes. There are several waveform options if the first program is not the right fit. Device checks and reprogramming are part of normal care. They are not a sign something went wrong.

The first idea came from the gate control theory of pain, put forward by Melzack and Wall in 1965. It said that firing up large sensory fibers in the dorsal column could block pain signals carried by smaller fibers. Think of a gate that closes on the pain. That model explained the tingling older systems made in the painful area, since the same large fibers carry touch.

Today we know more. Stimulation also changes neurotransmitter (nerve chemical) activity in the dorsal horn of the spinal cord. It also changes pathways higher up, toward the brain. That is why newer high-frequency and burst waveforms ease pain with no tingling at all. In practice, a device that does not feel like it is doing anything may still be working. A program you cannot feel is not broken.

The landmark randomized comparison is Kumar and colleagues, published in Pain in 2007. It was a multicenter trial of spinal cord stimulation versus standard medical care in failed back surgery syndrome. Results held at twenty-four months in the PROCESS follow-up. That proof is why lasting radicular pain after spine surgery is the best-proven use.

It is also why we insist on the trial. The published results come from patients who first passed a trial. So a permanent implant placed without one does not have the same proof behind it. If your trial does not give a clear response, the honest answer is that the data predicting benefit does not apply to you.

Spinal cord stimulation is not right for everyone. The screening exists to protect you from an implant that will not help. We usually do not offer it with an untreated infection, a bleeding risk that has not been fixed, or trouble handling the device. We also usually do not offer it for pain that is mostly mechanical, not nerve pain. Stimulation changes nerve signals. So pain from an untreated structural problem is usually better handled by treating that problem directly.

Most insurers also require a psychological evaluation before they approve the trial. This is not a test of whether your pain is real. Untreated depression, anxiety, and substance use all lower the odds that a trial works, by a measurable amount. When they are present, we treat them first rather than go ahead and hope. Our counseling services are part of the same practice for exactly this reason.

Spinal cord stimulation almost always needs prior authorization, and the paperwork rules are specific. Insurers usually want a record of conservative care that did not work. They want imaging that fits the pain. Where it applies, they want nerve testing or diagnostic block results that line up. They want a finished psychological evaluation. And they want a written trial result showing real improvement.

Our office puts together and sends in that package. In practice, there is usually a gap of several weeks between a good trial and the permanent implant while approval goes through. We will tell you where you are in that process. We will not leave you to guess. And we check your specific benefits before the trial, not after.

The most common problem is lead migration. The lead shifts a little from where it was placed, and the area it covers changes. Reprogramming usually fixes this. Sometimes it needs a revision procedure. Infection at the generator pocket is uncommon. But it is the problem that most often means taking hardware out.

Other issues are practical, not dangerous. Depending on the system, the generator either needs regular recharging or will need replacing when the battery runs down. Some patients find the generator pocket sore at first, mostly if they are thin. None of this is hidden from you before the trial. The whole system can be removed if you decide it is not worth keeping.

MRI. Many current systems are MRI-conditional. That means scans are possible under specific conditions set by the maker. Carry your device card. Tell any imaging center what you have before a scan is booked. The conditions differ by system and by body part.

Security screening. Airport screening will not harm the device. But the device may set off a metal detector. Your device card is for this.

Driving. Some makers advise turning stimulation off while driving. Your device instructions will say. Follow them, not a general rule.

Adjustment over time. Programming is not set once. Pain patterns change. Reprogramming to keep up with them is routine care, not a sign of a problem.

Both block pain signals with electrical stimulation. The choice depends on how spread out the pain is. Spinal cord stimulation covers bigger areas — a whole limb, or the lower back and both legs. That is because the lead sits in the epidural space, where many nerve paths come together.

When one nerve we can name is causing the pain, peripheral nerve stimulation puts the electrode right at that nerve. It is often the better-aimed option. Choosing between them is part of the evaluation, not something to settle ahead of time.