First evidence of a biomarker-based dose-response relationship in chronic pain using physiological closed-loop spinal...

Area of Science:

• Neuromodulation
• Pain Management
• Biomedical Engineering

Background:

• Spinal cord stimulation (SCS) uses electricity as a pain relief medication, unlike conventional drugs with defined plasma concentrations.
• Open-loop SCS delivery is inconsistent due to epidural space dynamics, leading to variable electric field activation.
• Physiologic closed-loop control (PCLC) devices offer consistent, accurate SCS therapy, minimizing dosage errors per FDA guidance.

Purpose of the Study:

• To assess the relationship between neurophysiological indicator metrics and pain reduction in SCS patients.
• To establish objective measures for SCS therapy dose, neural activation, and accuracy.
• To explore the potential for personalized SCS therapy optimization.

Main Methods:

• Over 600 SCS patients were analyzed.
• Neurophysiological metrics including therapy dose, time above neural activation threshold, and therapy accuracy were assessed.
• These metrics were correlated with reported pain reduction.

Main Results:

• Significant relationships were found between objective SCS metrics and pain relief across the patient population.
• The study provides the first evidence of a dose-response relationship in SCS therapy.
• Higher electrical dose, increased time over the evoked compound action potential (ECAP) threshold, and greater therapy accuracy correlated with better patient outcomes.

Conclusions:

• Objective electrophysiological inputs are measurable and can inform SCS therapy optimization.
• Personalized SCS therapy can be enhanced by utilizing unique, objective, measurable electrophysiological inputs.
• The findings support the development of PCLC systems for more precise and effective SCS treatment.