Burst & High-Frequency Spinal Cord Stimulation Differentially Effect Spinal Neuronal Activity After Radiculopathy

Area of Science:

• Neuroscience
• Pain Management
• Biomedical Engineering

Background:

• Spinal cord stimulation (SCS) is used for neuropathic pain, but comparisons between burst and high-frequency (HF) modes are lacking.
• The specific effects of burst SCS recharge types and varying HF SCS frequencies on neuronal activity remain unclear.

Purpose of the Study:

• To compare the effects of different spinal cord stimulation (SCS) modes on neuronal hyperexcitability.
• To investigate how burst SCS recharge (active vs. passive) and HF SCS frequencies alter neuronal firing rates in a rat pain model.

Main Methods:

• Neuronal firing rates in the spinal dorsal horn were measured in rats with nerve compression pain.
• Motor thresholds and evoked neuronal responses were recorded before and after SCS using 10 kHz HF, 1.2 kHz HF, burst with active recharge, and burst with passive recharge modes.
• Spontaneous firing rates were also assessed.

Main Results:

• The 10 kHz HF SCS mode exhibited a significantly higher average motor threshold compared to other modes.
• Burst SCS with passive recharge was the only mode that significantly reduced both evoked and spontaneous neuronal firing rates following noxious stimuli.
• High-frequency and burst SCS demonstrated distinct effects on motor thresholds and neuronal firing patterns.

Conclusions:

• High-frequency and burst spinal cord stimulation have different mechanisms of pain relief, evidenced by varying motor thresholds and effects on neuronal activity.
• Burst SCS with passive recharge shows promise for reducing neuronal hyperexcitability and may be crucial for neurophysiological pain management.