What Is a Spinal Cord Stimulator?

A spinal cord stimulator (SCS) is a small implanted device that uses mild electrical signals to modify pain signaling before it reaches the brain.

It works by delivering controlled electrical impulses to the spinal cord through thin wires (called leads). These impulses interfere with or “modulate” abnormal pain signals traveling along the spinal cord.

SCS does not remove the underlying structural issue. Instead, it changes how the nervous system processes pain, a concept known as neuromodulation.

Think of it as adjusting the nervous system’s volume knob rather than trying to remove the speaker.

How Does a Spinal Cord Stimulator Work?

Pain signals travel from injured tissue to the spinal cord and then up to the brain. In chronic pain conditions, this signaling pathway can become amplified or dysregulated.

SCS systems:

• Deliver low-level electrical stimulation to the dorsal columns of the spinal cord

• Disrupt or override abnormal pain transmission

• Reduce perception of chronic nerve-related pain

Modern systems may offer:

• Traditional paresthesia-based stimulation (tingling replaces pain)

• High-frequency stimulation (no tingling sensation)

• Burst stimulation patterns

• MRI compatibility (depending on device)

The type of system is selected based on the patient’s condition and goals.

Who Is a Candidate for Spinal Cord Stimulation?

SCS is typically considered for patients with:

• Chronic neuropathic pain

• Failed back surgery syndrome (persistent pain after spine surgery)

• Chronic radiculopathy (nerve pain in arms or legs)

• Complex Regional Pain Syndrome (CRPS)

• Peripheral neuropathy in select cases

• Intractable lower extremity pain not responding to conservative care

Candidates usually:

• Have had pain for months to years

• Have tried medications, therapy, and injections

• Do not have a surgically correctable structural issue

• Undergo psychological screening (standard part of the evaluation process)

The SCS Trial: A Reversible First Step

One of the most important features of spinal cord stimulation is that it is first tested before permanent implantation.

What Is the Trial?

During the trial:

1. Temporary leads are placed through a needle using fluoroscopic guidance.

2. The leads are connected to an external battery worn outside the body.

3. The patient goes home and tests the system for several days (typically 3–7 days).

No permanent implant is placed during the trial.

What Determines Success?

A trial is typically considered successful if the patient experiences:

• Significant pain reduction (often ≥50%)

• Improved sleep

• Improved function

• Reduced reliance on pain medication

If the trial is not helpful, the leads are removed, and no permanent device is implanted.

Permanent Implant Procedure

If the trial is successful, a permanent system may be implanted.

This involves:

• Placing leads in the epidural space

• Implanting a small battery (generator) under the skin, usually in the upper buttock or abdomen

• Connecting the leads to the generator

The device is programmable and adjustable.

The procedure is typically performed in a surgical center under sedation.

Recovery After Implant

• Light activity for several weeks

• Avoid bending, twisting, or heavy lifting during initial healing

• Gradual return to normal activities

• Device programming adjustments as needed

Most patients work closely with the device representative and physician to optimize settings.

Benefits of Spinal Cord Stimulation

• Reversible and trial-based

• Minimally invasive compared to major spine surgery

• Can significantly reduce nerve-related pain

• May reduce opioid use

• Adjustable and programmable

• Does not destroy nerves

Risks and Considerations

While SCS is generally safe, potential risks include:

• Infection

• Lead migration (movement of the wire)

• Hardware malfunction

• Bleeding

• Pain at implant site

• Need for revision surgery

Careful patient selection significantly improves success rates.

Frequently Asked Questions

Will I feel the stimulation?
It depends on the system. Some systems create a mild tingling sensation. Others (high-frequency systems) are designed to operate without noticeable sensation.

Can it be removed?
Yes. Spinal cord stimulators are removable.

Will it cure my pain?
SCS does not cure the underlying condition. The goal is meaningful pain reduction and improved function.

Can I have MRI scans?
Many modern systems are MRI-conditional. Device selection considers future imaging needs.

Is Spinal Cord Stimulation Right for Me?

SCS is typically considered after conservative treatments have failed and when surgery is not indicated or has not fully resolved symptoms.

A comprehensive evaluation ensures:

• Pain is neuropathic in nature

• Structural issues have been addressed

• Expectations are realistic

• Psychological readiness is confirmed

Neuromodulation works best in well-selected patients.

Reference

North American Neuromodulation Society (NANS). “Spinal Cord Stimulation.” Available at: https://neuromodulation.org