Remote therapeutic effectiveness of acupuncture in treating myofascial trigger point of the upper trapezius muscle.

OBJECTIVE: This study aimed to investigate the remote effect of acupuncture (AcP) on the pain intensity and the irritability of the myofascial trigger point in the upper trapezius muscle.

DESIGN: Forty-five patients were equally divided into three groups: patients in the placebo control group received sham AcP, those in the simple needling group were treated using simple needling, and those in the modified AcP received AcP with the rapid "screwed in and out" into multiple sites to elicit local twitch responses. The acupoints of Wai-guan and Qu-chi were treated. The outcome assessments included changes in subjective pain intensity, pressure pain threshold, range of motion, and mean amplitude of endplate noise in the myofascial trigger point region.

RESULTS: Immediately after acupuncture, all measured parameters improved significantly in the simple needling and modified AcP groups, but not in the placebo control group. There were significantly larger changes in all parameters in the modified AcP group than that in the simple needling group.

CONCLUSIONS: The myofascial trigger point irritability could be suppressed after a remote acupuncture treatment. It appears that needling to the remote AcP points with multiple needle insertions of modified AcP technique is a better technique than simple needling insertion of simple needling technique in terms of the decrease in pain intensity and prevalence of endplate noise and the increase in pressure pain threshold in the needling sites (represented either AcP points and or myofascial trigger points). We have further confirmed that the reduction in endplate noise showed good correlation with a decreased in pain.