Somatic sympathetic vasomotor changes documented by medical thermographic imaging during acupuncture analgesia.

Acupuncture is widely used for pain relief in many musculoskeletal disorders, and evidence suggests that modulation of the sympathetic nervous system responses which play an integral part in somatic pain, is an important mechanism of acupuncture action. This prospective study of 20 patients with neck and arm pain measured finger temperature, controlled by somatic sympathetic vasomotor activity before and after needle acupuncture. Responses were correlated with visual analogue scale (VAS) of pain severity. An association was found between pain relief and reduced sympathetic vasomotor activity. In 10 patients with significant reduction in visual analogue scale (VAS) pain (p less than .05), the mean change in temperature (delta t degrees C) was 0.55 (SD +/- 0.86) with significant difference in pre to post treatment temperatures (p less than .01). In 10 patients without significant pain relief on VAS scoring (p greater than .05), the mean t degrees C was 0.20 (SD +0.72) without significant difference in pre to post treatment temperatures (p greater than .05). The relevance of somatic sympathetic influences on musculoskeletal pain and modulation of sympathetic activity by acupuncture will be discussed.