Increased Spinal Electrical Activity in Chronic Intractable Pain Patients

Friday, May 3, 2024

2:30 PM – 2:34 PM CT

Location: S401ab

Presenting Author(s)

Thaddeus J. Leiphart (he/him/his)

Researcher
Inova Fairfax Hospital

Co-Author(s)

James Leiphart, MD, PhD

Program Director, Inova Fairfax Hospital Neurosurgery Residency, Professor, University of Virginia
Inova Medical System, University of Virginia Inova Campus
Falls Church, Virginia, United States

Disclosure(s):

James Leiphart, MD, PhD: No financial relationships to disclose

Thaddeus Leiphart, n/a: No financial relationships to disclose

Introduction: Evidence of increased CNS activity in relation to chronic intractable pain has been demonstrated using various techniques including invasive spinal cord electrode recordings in animal models. Direct evidence of increased spinal electrical activity in humans with chronic intractable pain may help in better understanding the physiology underlying the pain. Analysis of abnormal signal frequencies may help direct therapies as novel spinal cord stimulation frequencies have recently been introduced.

Methods: We performed spinal cord electrical activity recordings from nine chronic intractable pain patients undergoing awake surgery for spinal cord stimulator implantation as part of their clinical care. Paddle electrodes were placed via laminectomy with awake testing to guarantee midline placement. After placement and testing the paddle lead was used for one minute of electrical recording from each side of the electrode. These recordings were performed using Grass LP511 AC amplifiers, National Instruments NI USB -6218 DAQ system and a Toshiba personal computer. 60 Hz artifact signals were removed. T-test and Analysis of Variance statistics were performed using Minitab-19 software.

Results: Grouped by signal frequency from 1 Hz to 120 Hz and comparing the difference between the amplitude of the left sided signals and the right sided signals, there was an overall statistically significant difference between the patients with predominantly left sided pain and those with predominantly right sided pain (p <.001). The amplitude of electrical activity was much greater on the left than the right for left sided pain patients, and slightly greater on the right than the left for right sided pain patients. Individual frequencies did not demonstrate statistically significant differences.

Conclusion : This study provides evidence of increased spinal cord electrical activity related to chronic intractable pain. This activity difference was found throughout the frequencies analyzed with no frequency specific differences.