%0 Journal Article %T Effect of acupuncture depth on muscle pain %A Kazunori Itoh %A Yoichi Minakawa %A Hiroshi Kitakoji %J Chinese Medicine %D 2011 %I BioMed Central %R 10.1186/1749-8546-6-24 %X A total of 22 healthy volunteers performed repeated eccentric contractions to induce muscle soreness in their extensor digital muscle. Subjects were assigned randomly to four groups, namely control group, skin group (depth of 3 mm: the extensor digital muscle), muscle group (depth of 10 mm: the extensor digital muscle) and non-segmental group (depth of 10 mm: the anterior tibial muscle). Pressure pain threshold and electrical pain threshold of the skin, fascia and muscle were measured at a point 20 mm distal to the maximum tender point on the second day after the exercise.Pressure pain thresholds of skin group (depth of 3 mm: the extensor digital muscle) and muscle group (depth of 10 mm: the extensor digital muscle) were significantly higher than the control group, whereas the electrical pain threshold at fascia of muscle group (depth of 10 mm: the extensor digital muscle) was a significantly higher than control group; however, there was no significant difference between the control and other groups.The present study shows that acupuncture stimulation of muscle increases the PPT and EPT of fascia. The depth of needle penetration is important for the relief of muscle pain.Recent clinical investigations on the myofascial pain syndrome and fibromyalgia focused on the existence of tender point and/or trigger point, with some literature emphasizing the importance of the tender and/or trigger points as diagnostic points [1-5]. Moreover these points have also been demonstrated as treatment points [6-9]. Sensitivity of tenderness and the number of tender points, being closely related to symptom severity can be used to evaluate the effectiveness of a certain treatment [1-5].Acupuncture treatment includes tender or trigger points known as Ah-Shi or 'Oh-Yes' for treatments of myofascial pain syndrome and fibromyalgia. Studies have shown that application of acupuncture at these points improves symptoms in these disorders [10-12]. Needling points are most commonly chosen accordi %U http://www.cmjournal.org/content/6/1/24