Pressure pain threshold and needle acupuncture in chronic tension-type headache--a double-blind placebo-controlled study.

In order to examine the role of muscular mechanisms in chronic tension-type headache a study with needle acupuncture was performed. Needle acupuncture could be of therapeutic value because it has shown some positive effects in myofascial pain syndromes. We performed a double-blind, placebo-controlled study with 39 patients (mean age 49.0 years, SD=14.8) fulfilling the International Headache Society criteria for chronic tension-type headaches. Participants were randomly assigned to verum or placebo condition. Six weeks after end of treatment no significant differences between placebo and verum could be observed with respect to visual analogue scale and frequency of headache attacks. Nevertheless, pressure pain thresholds significantly increased for the verum group. The findings of our study support the hypothesis that peripheral mechanisms - such as increased muscle tenderness - only play a minor role in the pathogenesis of chronic tension-type headache.