Streitberger, K., Eichenberger, U., Schneider, A., Witte, A., and Greher, M. (2007)
Pericard 6 (P6) is one of the most frequently used acupuncture points, especially in the prevention of nausea and vomiting. Anatomically the median nerve is located very superficially at this point. This study aims to investigate the distance between the needle tip and the median nerve during acupuncture at P6 using observational ultrasound. It suggests that de qi (a sensation common with acupuncture treatment) is evoked when the needle comes into contact with the epineural tissues, thereby preventing nerve penetration.
The study found that from the 97 patients where complete data could be obtained, the mean distance from the needle tip to the nerve was 1.8mm. Nerve contact was recorded in 52 cases, of which 14 cases involved nerve penetration. De qi was elicited in 85 cases. There was no association found between the number of nerve contacts and de qi, and there were no complications found at the 1 week follow up stage.
The study suggests that although the rate of median nerve penetrations was suprisingly high, there were no neurological complications as a result of this. De qi at P6 does not depend on median nerve contact, nor does it prevent median nerve penetration.
The Journal of Alternative and Complementary Medicine. 2007, 13:5 585-592