What are the benefits and risks of using a nerve stimulator for chronic pain management?

Benefits and Risks of Nerve Stimulation for Chronic Pain Management

Nerve stimulation for chronic pain management offers potential benefits for specific conditions but lacks robust evidence for long-term efficacy and should be considered only after exhausting conventional treatments due to limited high-quality clinical evidence supporting its widespread use. 1, 2

Types of Neurostimulation

• Neurostimulation therapies include spinal cord stimulation (SCS), peripheral nerve stimulation (PNS), peripheral nerve field stimulation (PNFS), deep brain stimulation (DBS), and motor cortex stimulation 3, 4
• These therapies target different neural structures including the spinal cord, thalamus, periaqueductal gray matter, motor cortex, and peripheral nerves 3

Benefits of Nerve Stimulation

Pain Reduction

• In a 2023 systematic review of high-quality randomized controlled trials (RCTs), neurostimulation was found to be generally effective as an adjunctive treatment for chronic pain with long-term follow-up 1
• Peripheral nerve stimulation showed good pain relief (>50%) in 61% of patients in a retrospective study with a mean follow-up of 31 months 5
• Specific conditions showing benefit include:
  • Peripheral nerve field stimulation for back pain 1
  • Spinal cord stimulation for back and leg pain, persistent spinal pain syndrome, and painful diabetic neuropathy 1
  • Dorsal root ganglion stimulation for complex regional pain syndrome 1

Functional Improvement

• 47% of patients reported significant improvement in activity levels following peripheral nerve stimulator implantation 5
• Neurostimulation may help reduce reliance on opioid medications for pain management 6

Risks and Limitations

Procedural Complications

• Infection is a significant risk that may require device removal (15% removal rate in one study) 5
• Neuromodulator systems may experience unwanted paraesthesias or programming issues requiring additional management 3
• Implanted devices may require maintenance, battery replacement, or lead repositioning 3

Evidence Limitations

• Evidence supporting neurostimulation efficacy has been collected predominantly from retrospective series or prospective studies with significant design limitations 3, 2, 4
• There is a lack of clinical studies with sufficient participant numbers, matched control groups, sham stimulation, randomization, and prospectively defined endpoints 3, 2
• Current clinical guidelines classify many forms of neurostimulation as having insufficient evidence for routine treatment of chronic pain 7, 4

Device-Specific Concerns

• Abrupt cessation of certain neurostimulation therapies (particularly intrathecal drug delivery systems) can lead to severe withdrawal syndromes 3
• Long-term risks and benefits of peripheral nerve stimulation have not been well studied, as most available information is based on shorter-term improvements 6

Current Evidence Status

• The 2025 systematic review and meta-analysis of RCTs on peripheral nerve stimulation found only "fair" (Level III) evidence with moderate certainty and recommendation strength 8
• The American Society of Anesthesiologists (ASA) recognizes subcutaneous peripheral nerve stimulation as only potentially beneficial for painful peripheral nerve injuries 7
• Many neurostimulation approaches are still considered experimental due to lack of widespread geographic use, general acceptance, or recognition for reimbursement by major insurers 2

Clinical Considerations

• Neurostimulation should be considered only after failure of conventional treatments including medications, physical therapy, and less invasive interventions 7, 6
• During pandemic situations or other healthcare access limitations, special consideration must be given to managing patients with existing neurostimulation devices 3
• Patients should be carefully selected and educated about realistic expectations, potential complications, and the experimental nature of some neurostimulation approaches 2, 7

Future Directions

• Future studies should require unambiguous diagnoses as entry criteria and involve randomization, parallel control groups with sham stimulation, and blinding of patients, investigators, and device programmers 3
• Given the chronicity of symptoms and stimulation therapies, efficacy should be studied for 1 year or longer after device implantation 3, 1
• Research examining whether neurostimulation offered early in the trajectory of chronic pain might be more effective is needed 9