Local skin sensory changes after acupuncture.

Forty normal subjects were assessed for local skin sensory changes of the knees after acupuncture needle insertion. Correct insertion sites were used on one knee and incorrect sites on the other knee. No significant change of sensation was found over the L3 and L5 dermatomes when incorrect sites were used. Pain sensation was markedly diminished on the side where correct sites were used; minimal transient diminished sensation of heat and vibration was noted.