Are Spinal Cord Stimulators Safe? Risks & Complications

Spinal cord stimulators carry a meaningful complication rate, but the vast majority of problems that arise are hardware-related and manageable rather than life-threatening. A recent systematic review pooling data from over 3,400 patients found that about 24% experienced at least one adverse event, while only 3% experienced a serious one.¹ That ratio matters: most complications involve a lead that shifts out of position or a device that needs adjustment, not neurological damage or dangerous infections. Still, the overall complication rate has been reported as high as 32 to 43% when every minor issue is counted, so anyone considering one of these devices deserves a clear picture of what can go wrong and how likely each problem actually is.²

How the Numbers Break Down

The gap between “24% of patients have at least one adverse event” and “the overall complication rate is up to 43%” is not a contradiction. It reflects how complications are counted. Some patients experience more than one problem over the life of their device, so the total number of events per patient can exceed the percentage of patients affected. The meta-analysis calculated roughly 0.35 events per patient on average, meaning the typical patient with a complication had about one, but some had multiple.¹ Older reviews that cite the higher figures often include every minor nuisance, from temporary discomfort at the battery site to a brief programming adjustment. That does not make those numbers wrong, but it does mean the headline rate can give a scarier impression than the lived experience of most patients.

Lead migration is the single most frequent problem, occurring at more than twice the rate of infection. The same meta-analysis found lead migration at about 7 events per 100 patient-years compared to roughly 3 events per 100 patient-years for infection. Revision procedures, where the device is surgically adjusted but not removed, happened more often than full explantations.¹ In other words, when something goes wrong, it is more often fixable than final.

Lead Migration and Lead Fracture

The stimulator lead is a thin wire threaded into the epidural space alongside the spinal cord. It delivers the electrical pulses that disrupt pain signals. Because it sits in a dynamic environment where you bend, twist, and move all day, it can shift from its original position. When it does, the stimulation pattern changes and pain relief fades or moves to the wrong area. One large retrospective study found that about 3% of implant procedures eventually required at least one reoperation to reposition or replace a lead that had migrated or was providing inadequate coverage.³

Lead fracture is a separate mechanical failure. Over a near-twelve-year period, one study documented an overall fracture rate of about 4.3% across 305 permanently implanted leads, though newer multilumen concentric lead designs showed zero fractures over an average follow-up of four and a half years.⁴ Engineering improvements have clearly made a difference here, and lead durability is one area where newer-generation devices are genuinely better than what was available a decade ago.

Lead migration can also create a downstream safety issue beyond just losing pain relief. A migrated or fractured lead can change whether your device remains safe for an MRI scan. Many spinal cord stimulators are labeled “MR-conditional,” meaning they are cleared for MRI only under specific conditions related to lead position, lead integrity, and battery connection. If any of those change post-implant, the MRI clearance may no longer apply.⁵ This is worth discussing with your pain specialist if you ever need an MRI after implantation.

Infection

Any surgery involving implanted hardware carries infection risk, and spinal cord stimulators are no exception. A multicenter retrospective study of 2,737 implant procedures found an infection rate of about 2.5%. The most common signs were localized pain around the incision site and skin redness. Staphylococcus aureus, a common skin bacterium, was the most frequent culprit, and the generator pocket rather than the spinal lead site was the most common location for infection to take hold.⁶

Infection after a spinal cord stimulator implant is serious because it often means the device has to come out entirely. In an analysis of adverse events reported to a federal device-experience database, the most common procedural complication logged was non-neuraxial infection, accounting for over half of procedural entries. And the most common way these complications were resolved was full explantation rather than revision or drainage alone.⁷ So while the infection rate itself is fairly low, the consequences when it does happen are significant, often requiring additional surgery and a period without the stimulator.

Review articles note that biological complications including infection, dural puncture, and skin erosion have become less common over time as techniques and perioperative protocols have improved.⁸ Strict sterile technique, appropriate antibiotic prophylaxis, and careful patient selection all contribute to keeping the risk low.

Bleeding and Hematoma

The most feared surgical complication is a hematoma, particularly an epidural hematoma, which involves blood collecting in the spinal canal where it can compress the spinal cord. A systematic review and meta-analysis found a pooled incidence of neuraxial hematoma of about 0.3%. Most were epidural hematomas. The series included one death from an intracranial subdural hematoma in a patient who was not on blood thinners, and one intracranial hemorrhage in a patient who was on anticoagulant bridge therapy.⁹ A 0.3% incidence is low in absolute terms, but because the consequences can be catastrophic, surgeons take bleeding risk seriously.

This is why your medical team will ask you to stop certain blood thinners before surgery and will scrutinize your medication list carefully. A study examining over 640 percutaneous spinal cord stimulator procedures, including more than 100 in patients who had taken aspirin or NSAIDs within a week of the procedure, found zero cases of epidural hematoma.¹⁰ A separate study looking specifically at patients who routinely use anticoagulants found that, when those medications were appropriately suspended around surgery, anticoagulant users had no significantly increased risk of bleeding or clotting complications compared to patients not on blood thinners. A small exception involved patients on enoxaparin combined with other anticoagulants, where a handful of cases showed higher adverse event rates.¹¹ The takeaway for patients on blood thinners is that the procedure is not automatically off the table, but it does require careful coordination with your prescribing physician.

Dural Puncture

During lead placement, the surgeon works in the epidural space, the area just outside the membrane (dura) that encloses the spinal cord and cerebrospinal fluid. Occasionally the needle or lead inadvertently pierces that membrane. This dural puncture can cause a spinal headache, a distinctive positional headache that worsens when you sit or stand and improves when you lie flat. It occurs because cerebrospinal fluid leaks through the puncture site, dropping the fluid pressure around the brain.¹²

Dural puncture was the third most commonly reported procedural complication in the federal adverse-event database analysis, behind infection and new neurological symptoms.⁷ Most post-dural puncture headaches resolve on their own or with conservative treatment like bed rest, fluids, and caffeine. In persistent cases, a blood patch, where a small amount of your own blood is injected near the puncture to seal it, is the standard fix. The headache is unpleasant but almost always temporary.

Generator Pocket Pain and Soft Tissue Issues

The implantable pulse generator, the battery unit that powers the stimulator, gets placed in a pocket of tissue usually in the buttock or lower flank area. Some patients develop persistent pain at this site. Causes range from the mundane to the mechanical: clothing waistbands pressing on the device, the generator rotating within its pocket, the battery edge contacting a rib after weight loss, or trauma to the area. One review catalogued these triggers and found that device rotation and trauma to the battery site were among the more common culprits.¹³

Seromas, which are pockets of clear fluid that collect around the implant, are another soft tissue complication. They can appear early after surgery or, in rare cases, decades later. One case report described a seroma that developed around a spinal cord stimulator and its extension wiring 20 years after the original implant, causing pain and swelling that prompted medical evaluation.¹⁴ This is a reminder that even long after the surgical site has healed, implanted hardware can occasionally cause new problems.

Rare but Serious Long-Term Risks

The most sobering long-term risk involves fibrous scar tissue forming around the implanted leads inside the spinal canal. This fibrotic encapsulation is rare, but when it happens, the growing scar tissue can compress the spinal cord itself, causing weakness, numbness, or even progressive paralysis. A review of reported cases found that both large paddle-type electrodes placed through open surgery and smaller percutaneous rod-type leads could trigger this response, suggesting it is an inherent risk of having a foreign body in the epidural space rather than something caused by the surgical approach alone. In those cases, loss of stimulation effectiveness (tolerance) often preceded the discovery of the fibrous mass, with a median interval of about five years from implantation to symptom onset, though the range stretched from nine months to 17 years.¹⁵

One case report described a patient who, ten years after a spinal cord stimulator was placed, developed progressive paraplegia, worsening pain at the level of the electrodes, and loss of bowel and bladder control. Imaging confirmed the spinal cord was being compressed by fibrotic tissue at the electrode level. After the fibrotic tissue and electrodes were surgically removed, the radicular pain resolved but neurological function returned only minimally.¹⁶ These cases are extremely uncommon, but they underscore why gradual loss of stimulator effectiveness should not be dismissed as simple tolerance without further investigation.

When and Why Devices Get Removed

A systematic review covering over 13,000 patients implanted between 1984 and 2024 found that roughly 10% eventually had their stimulators explanted. The most common reason was simply that the device stopped providing adequate pain relief, accounting for about 38% of removals. Lead failure was responsible for about 15%, and infection for about 14%.¹⁷ That loss-of-efficacy figure is worth sitting with. It does not necessarily mean the stimulator failed in an engineering sense; chronic pain itself can change over time, and what worked initially may not work indefinitely.

A smaller single-center study found an explantation rate of about 7% with a median follow-up of two years. In that cohort, younger age, tobacco use, and certain mental health conditions were all associated with a greater likelihood of having the device removed.¹⁸ This aligns with broader evidence that psychological factors matter for stimulator outcomes. Psychiatric comorbidities have been linked to worse results, which is why many programs require psychological screening before implantation.¹⁹ This is not about gatekeeping. It is about identifying patients who may benefit from additional support or whose expectations about outcomes need to be calibrated before committing to surgery.

Battery and Charging Realities

Modern stimulators often use rechargeable implantable pulse generators, partly to reduce the need for battery-replacement surgeries. In theory, a rechargeable unit should last many years longer than a non-rechargeable one. In practice, recent evaluations have raised questions about whether rechargeable batteries truly deliver the extended lifespan manufacturers initially projected.⁸ When a non-rechargeable battery runs out, the generator must be surgically replaced, which is a relatively minor outpatient procedure but still carries the usual risks of anesthesia, infection, and pocket-site complications. Patients considering a rechargeable system should weigh the convenience of fewer replacements against the commitment of regular charging sessions, which can take 30 minutes to a few hours depending on the device.

How Spinal Cord Stimulators Compare to Repeat Spine Surgery

For people with failed back surgery syndrome, the relevant safety comparison is often not “stimulator versus doing nothing” but “stimulator versus going back to the operating room for another spine surgery.” A randomized controlled trial followed patients assigned to either spinal cord stimulation or repeat operation. By an average follow-up of about three years, 62% of patients originally assigned to reoperation had crossed over to try stimulation instead, compared with 26% who crossed the other direction. The average cost to achieve a successful outcome was dramatically lower for the stimulation group. No patients who crossed from stimulation to reoperation achieved a successful outcome despite significant expenditure.²⁰ That crossover pattern tells a story about both effectiveness and, indirectly, about safety: repeat spine surgery carries its own serious risks, including scar tissue formation, hardware failure, and nerve injury. The stimulator’s risk profile, dominated by lead migration and treatable infections, looks different from the risks of another open spinal procedure.

Legal Patterns and What They Reveal

Malpractice litigation data offers a different lens on stimulator complications. An analysis of legal cases found that the most commonly litigated issues were battery or pulse generator malfunction (about 36% of cases), lead complications (about 29%), and surgical complications (about 20%). The majority of cases resulted in a verdict for the physician or facility. Claims related to infection were more likely to result in a defense verdict, while claims involving neurological injury were more likely to result in a verdict for the patient.²¹ The claims themselves tracked a broader analysis of implantable pain devices, which identified infection, inadequate pain relief, trauma to the spinal cord or cauda equina, and retained catheter fragments as the main categories of alleged injury.²²

What stands out in the litigation data is that device malfunction and lead problems, not surgical negligence, dominate the complaints. This mirrors the clinical complication data: hardware issues are the most common problem. And the fact that most cases favored the defense suggests that many of these complications, while real and frustrating for patients, are recognized risks of the procedure rather than errors in care. That distinction matters if you are weighing whether to proceed. The question is not whether complications happen, because they clearly do at a non-trivial rate. The question is whether the complications you are most likely to encounter are ones you can live with, and whether the potential pain relief justifies accepting that risk.

Cervical Versus Thoracic Lead Placement

Spinal cord stimulators can be placed at different levels of the spine depending on where the pain originates. Cervical leads target neck, arm, and upper-body pain, while thoracic leads target mid-back, lower-back, and leg pain. Some patients get both. A natural concern is whether placing leads higher in the spine, closer to the brainstem and in a narrower canal, carries additional risk. A single-center retrospective review of 10 kHz stimulation using cervical leads, thoracic leads, or both found that the safety profile was comparable regardless of lead location.²³ This is reassuring, though the evidence base for cervical placement is smaller than for thoracic placement, so the confidence interval is wider.

1
PubMed. Complication Rates of Spinal Cord Stimulation: A Systematic Review and Meta-Analysis
2
PubMed. Complications of Spinal Cord Stimulator Trials and Implants: A Review
3
PubMed Central. Rates and Causes of Reoperations Following Spinal Cord Stimulation Within a 2-12 year Period
4
PubMed. The Long-Term Durability of Multilumen Concentric Percutaneous Spinal Cord Stimulator Leads
5
Taylor & Francis Online / Pain Management. MR-conditionality failure modes: a comparison across various spinal cord stimulators
6
PubMed. Spinal Cord Stimulator Related Infections: Findings From a Multicenter Retrospective Analysis of 2737 Implants
7
The Clinical Journal of Pain. Adverse Events Associated With 10-kHz Dorsal Column Spinal Cord Stimulation: A 5-Year Analysis of the Manufacturer and User Facility Device Experience (MAUDE) Database
8
PubMed. Complications of Spinal Cord Stimulators-A Comprehensive Review Article
9
PubMed. Incidence of Neuraxial and Non-Neuraxial Hematoma Complications From Spinal Cord Stimulator Surgery: Systematic Review and Proportional Meta-Analysis
10
Pain Medicine. Bleeding Complications in Patients Undergoing Percutaneous Spinal Cord Stimulator Trials and Implantations
11
PubMed Central. Safety of Spinal Cord Stimulation in Patients Who Routinely Use Anticoagulants
12
PubMed Central. Post Dural Puncture Headache After Spinal Cord Stimulator Lead Insertion Successfully Treated with Occipital Nerve Blocks
13
Pain Medicine. Treatment Strategies for Generator Pocket Pain
14
Pain Medicine Case Reports. Seroma Formation 20 Years After Spinal Cord Stimulator Insertion: A Case Report
15
PubMed Central. A Late Complication Related to Percutaneous Implantable Leads for Spinal Cord Stimulation: Myelopathy due to Fibrous Scar Tissue
16
American Journal of Physical Medicine & Rehabilitation. Progressive Paraplegia from Spinal Cord Stimulator Lead Fibrotic Encapsulation
17
PubMed Central. Spinal Cord Stimulation Explantation and Chronic Pain: A Systematic Review and Technology Recommendations
18
Neuromodulation. Risk Factors for Spinal Cord Stimulator Explantation
19
Interdisciplinary Neurosurgery. Psychiatric screening for spinal cord stimulation for complex regional pain syndrome: A literature review and practical recommendations for implementation
20
PubMed. Spinal cord stimulation versus reoperation for failed back surgery syndrome: a cost effectiveness and cost utility analysis based on a randomized, controlled trial
21
Interventional Pain Medicine. Analysis of reasons for medical malpractice litigation due to spinal cord stimulator
22
Anesthesiology. Injury and Liability Associated with Implantable Devices for Chronic Pain
23
PubMed Central. Efficacy and Safety of 10 kHz Spinal Cord Stimulation Using Cervical and Thoracic Leads: A Single-Center Retrospective Experience