Effect of electrical stimulation of peripheral nerves on neuropathic pain

Study Design. Changes in the electrophysiologic response of spinal dorsal horn neurons elicited by peripheral electrical stimulation were examined. Objective. To investigate whether the electrical stimulation of peripheral nerves causes an inhibition of pain at the spinal cord level. Summary of Background Data. The wide dynamic range-neurons studied were known to be excited by primary afferent fibers, not only combined A (delta) and C nociceptive fibers, but also low-threshold mechanoreceptive A (beta) fibers and A (delta) fibers of down hairs. The wide dynamic range neurons are classified as nociceptive neurons. Methods. Responses of wide dynamic range neurons in the lumbosacral dorsal horn to input from C fibers were studied in urethane chloralose-anesthetized cats. The posterior tibial nerve and sciatic nerve were stimulated simultaneously to examine the effect on the C fiber responses elicited by superficial peroneal nerve stimulation. Results. Simultaneous stimulation of the posterior tibial nerve and sciatic nerve was performed with superficial peroneal nerve C fiber stimulation. Conclusions. This study demonstrated that electrical stimulation of peripheral nerves leads to inhibitory input tp the pain pathways at the spinal cord level.