Spinal cord stimulation does not change peripheral skin blood flow in patients with neuropathic pain

Background and objective: Spinal cord stimulation has been used successfully for many years in the management of neuropathic pain. Nociceptive pathways are closely integrated into many autonomic reflexes. The aim was to test the hypothesis that pain relief caused by spinal cord stimulation is related to changes in peripheral skin blood flow. Methods: Twelve patients with spinal cord stimulators implanted as a treatment for neuropathic pain were entered into the study. Laser Doppler perfusion scanning was used as a direct method for selective measurement of changes in skin (peripheral) blood flow. Measurements were taken before and after the onset of spinal cord stimulation over the site of its sensory projection. The degree of pain relief due to spinal cord stimulation and the skin temperature of each patient were also recorded. Results: Apart from one patient, spinal cord stimulation did not change skin blood flow in a statistically significant manner. Conclusions: Pain relief due to spinal cord stimulation is not related to changes of skin blood flow.