This study was performed to observe the influence of sham and different verum acupuncture manipulations on skin temperature of the stimulated acupoint in healthy volunteers. Thirty-seven healthy volunteers with a mean age of 25.4 ± 2.2 years were enrolled in the study. All volunteers had experienced acupuncture before. They received sham acupuncture and two different kinds of verum acupuncture stimulation (lifting-thrusting and twisting-rotating) on Zusanli (ST36). The skin temperature of ST36 was measured before acupuncture, after needle insertion, after needle manipulation, immediately after removal of the needle, and as further control 5 minutes after removal of the needle using a FLIR i7 infrared thermal camera. During the measurement, the needling sensations of volunteers were enquired and recorded. During the sham acupuncture stimulation, the skin temperature of ST36 decreased in the first 5 minutes, when the point was exposed, and then increased gradually. During verum acupuncture stimulations, the skin temperature increased continually and then decreased in the last phase. The increase in temperature caused by lifting-thrusting stimulation was significantly higher than that of twisting-rotating manipulation, which may be related to the stimulation intensity.
Already in ancient times, doctors realized that acupuncture can influence the skin temperature. This is already mentioned in the first Chinese medical book
Around the time of the Jin-Yuan dynasty, the compound manipulations like directional supplementation and draining method (
This experiment tries to observe the influence of Cheng’s basic acupuncture manipulations—lifting-thrusting and twisting-rotating—on local acupoint skin temperature in a randomized study, which may lay a foundation for further research.
Through advertisements on the campuses, 37 healthy volunteers (30 female, 7 male) with a mean age of
Each volunteer underwent three measurements (two different kinds of verum acupuncture, see below, and sham acupuncture, in randomized order) every other day. To avoid discrepancies in manipulation, all acupuncture operations were performed by the same medical practitioner. The volunteers lay down on the back and exposed the right lower leg, so the Zusanli (ST36) acupoint could be marked in accordance with a textbook on
The location of the Zusanli acupoint (ST36).
Lifting and thrusting acupuncture needle manipulation.
Twisting and rotating acupuncture needle manipulation.
The operation of sham acupuncture.
The temperature of the lab was kept at 26°C, and the volunteers were asked to come into the room 5–10 mins ahead of schedule to adapt to the temperature. The skin temperature at ST36 was measured using a FLIR i7 (Flir Systems, Portland, OR, USA) thermographic camera 5 mins before acupuncture, immediately after needle insertion, after manipulation, immediately after removing the needle, and 5 mins after the needle removal (see Figure
Measurement procedure.
The volunteers were asked about their needling sensation after needle insertion and manipulation, respectively, were assessed by visual analogue scale (VAS). 0 means “no sensation at all,” and 10 means “too much to bear.”
Paired
Sham as well as verum acupuncture caused changes in the volunteers’ HR. After the 5 min phase of rest before acupuncture, HR decreased significantly. After verum acupuncture, needle manipulation, the lifting-thrusting as well as the twisting-rotating stimulation induced a significant increase in HR (compared to the phase of needle insertion), whereas during the sham procedure HR continued to decrease (cf. Table
The changes of volunteers’ HR (in [1/min]) during the experiment (
Before acupuncture | Needle insertion | Needle manipulation | Needle removal | After acupuncture | |
---|---|---|---|---|---|
Sham acupuncture | 71.03 ± 9.04 | 68.50 ± 8.29* | 68.15 ± 7.84 | 66.79 ± 7.32 | 67.82 ± 8.04 |
Lifting-thrusting | 73.68 ± 8.88 | 69.84 ± 9.93* | 69.43 ± 8.69 | 69.95 ± 9.71 | 71.22 ± 11.01* |
Twisting-rotating | 69.54 ± 11.47 | 65.27 ± 12.28* | 66.89 ± 10.80 | 67.32 ± 9.63 | 67.32 ± 11.50* |
After needle insertion, the skin temperature at ST36 decreased insignificantly following the sham procedure, but increased significantly in the two verum procedures. After manipulations, the temperature increase caused by lifting-thrusting stimulation was higher than that caused by sham acupuncture (see Figures
Temperature changes during the sham acupuncture procedure.
Temperature changes before, during, and after verum acupuncture—lifting-thrusting needle manipulation.
Temperature changes before, during, and after verum acupuncture—twisting-rotating needle manipulation.
Table
Changes in skin temperature (in [°C]) at ST36. The values in parentheses are the increases (decreases) of temperature with respect to the baseline values (
Before acupuncture | Needle insertion | Needle manipulation | Needle removal | After acupuncture | |
---|---|---|---|---|---|
Sham acupuncture | 34.87 ± 1.14 | 34.69 ± 1.02 | 35.18 ± 0.67 | 35.21 ± 1.06 | 35.23 ± 0.78 |
— | (−0.18) | (+0.31) | (+0.34) | (+0.36) | |
Lifting-thrusting | 34.53 ± 1.01 | 35.01 ± 0.85 | 35.37 ± 0.79 | 35.41 ± 1.05 | 35.35 ± 1.13 |
— | (+0.48) | (+0.84)* | (+0.88)* | (+0.82)* | |
Twisting-rotating | 34.49 ± 1.14 | 34.64 ± 1.38 | 34.86 ± 1.27 | 34.96 ± 1.09 | 34.91 ± 1.14 |
— | (+0.15) | (+0.37) | (+0.47) | (+0.42) |
All subjects could tell sham from verum acupuncture, but could not recognize the lifting-thrusting or twisting-rotating manipulations. After puncturing ST36, 71% of the subjects felt distension, 36% felt sourness, 16% felt pricking, and 10% felt numbness spreading. There was of course no statistical difference in the intensity of the needling sensation when the needle was inserted, but the intensity caused by lifting-thrusting stimulation was significantly higher than that of twisting-rotating manipulation (Table
VAS scores expressing the intensity of the needling sensation caused by needle insertion and manipulations (mean ± SD).
Needle insertion | Needle manipulations | |
---|---|---|
Lifting-thrusting | 3.93 ± 1.76 | 7.13 ± 1.90** |
Twisting-rotating | 4.72 ± 1.46 | 4.91 ± 2.32 |
Previous studies investigating acupuncture and skin temperature used compound reinforcing and reducing techniques to observe changes in skin temperature of the area along the meridian after puncturing the acupoint. A study by Li et al. showed that the skin temperature of acupoints changed according to the frequency of rotating acupuncture stimulation on ST36 [
The lifting-thrusting and twisting-rotating needle manipulations described and investigated in this experiment come from one of the authors’ (Professor X. Cheng) clinical experience. His very important results are summarized in
In one of these experiments [
Skin is the only heat dissipation way of the human body; when the body energy metabolism and heat production increases, heat dissipation through the skin increases, too, and so the surface temperature rises [
Both twisting-rotating (although not reaching the level of significance) and lifting-thrusting manipulations have been shown to make the skin temperature of the stimulated acupoint increase at first and decrease slowly later on. So, one can say that the lifting-thrusting method causes a stronger needling sensation and a stronger stimulation and induces a higher temperature at the stimulated acupoint. The stronger acupuncture stimulation may be related to the increase in blood perfusion [
Compared to sham acupuncture, deqi acupuncture can be able to increase the skin temperature of the stimulated acupoint. The range of temperature increase caused by lifting-thrusting stimulation is higher than that of the twisting-rotating method. This may be connected with the stimulus intensity. Further research is needed to verify these findings.
The authors declare that they have no conflict of interests.
The two corresponding authors T. Huang for China and Gerhard Litscher for Europe and all other authors are very thankful to Professor X. Cheng for his valuable help and agreement to be a coauthor of this paper. Their experiment is supported by the China National Science Foundation (81072760), the Returned personnel Foundation of MHRSS, and the Sino-Austrian projects (ZZ04007). The authors would like to thank Ms. Ingrid Gaischek, M.S., for her valuable support in creating figures and preparing the paper. The investigations were supported by the two Austrian ministries of Science and Research and of Health (evidence-based high-tech acupuncture and integrative laser medicine for prevention and early interventions of chronic diseases), the Eurasia Pacific Uninet, and the Department of Science of the City of Graz. Gerhard Litscher is also a Visiting Professor of the Institute of Acupuncture and Moxibustion at China Academy of Chinese Medical Sciences, Beijing, China.