Comparative Study on the Analgesic Effects of Different Moxibustion Methods with Tai-yi Moxa Stick in Treating Primary Dysmenorrhea

Wu Jiu-long, Chen Hong-yu2, Tang Yi-chun, Ma Xiao-yu3, Huan Jia-hui, Chen Ruo-yangMo Hui, Xu Xiu-zhu, Shen Xiao-jing, Wang Yu-fan, Zhang Jian-bin, Wang Ling-ling

1 The Second Clinical Medical College, Nanjing University of Traditional Chinese Medicine, Nanjing 210023, China

2 The First Clinical Medical College, Nanjing University of Traditional Chinese Medicine, Nanjing 210023, China

3 Department of English, Hong Kong Polytechnic University, Hong Kong, China

CLINICAL STUDY

Comparative Study on the Analgesic Effects of Different Moxibustion Methods with Tai-yi Moxa Stick in Treating Primary Dysmenorrhea

Wu Jiu-long1, Chen Hong-yu2, Tang Yi-chun1, Ma Xiao-yu3, Huan Jia-hui1, Chen Ruo-yang1Mo Hui1, Xu Xiu-zhu1, Shen Xiao-jing1, Wang Yu-fan1, Zhang Jian-bin1, Wang Ling-ling1

1 The Second Clinical Medical College, Nanjing University of Traditional Chinese Medicine, Nanjing 210023, China

2 The First Clinical Medical College, Nanjing University of Traditional Chinese Medicine, Nanjing 210023, China

3 Department of English, Hong Kong Polytechnic University, Hong Kong, China

Author:Wu Jiu-long, master degree candidate

Objective: To compare the therapeutic effects of two different moxibustion methods both with tai-yi moxa stick in treating primary dysmenorrhea.

Methods: Forty-three patients were randomized into two groups by the random number table according to their treatment orders. The causalgic group was intervened by causalgic stimulation with tai-yi moxa stick while the tepid group was treated by mild thermal stimulation with tai-yi moxa stick. Shiqizhui (EX-B 8) was selected for both groups. Visual analogue scale (VAS) was used for observation before and during the treatment by every 10 min to compare the clinical efficacies between the two groups.

Results: Before treatment, there was no statistically significant difference in pain intensity between the two groups (P＞0.05). After treatment, both groups achieved significant improvements in pain intensity (P＜0.05), but the inter-group difference in pain intensity was still statistically insignificant (P＞0.05), but the difference was enlarged comparing with that before treatment. The pain relief during the first 10 min of treatment was slower in the causalgic group than that in the tepid group. However, during the later 20 min, the pain relief in the calsalgia group gradually outpaced that in the tepid group.

Conclusion: The two moxibustion methods with tai-yi moxa stick both have a good instant analgesic effect in treating primary dysmenorrhea. For patients with primary dysmenorrhea, if 30 min is regarded as the treatment time, mild stimulation was suggested to be used for the first 10 min, and causalgic stimulation for the later 20 min to achieve a better curative effect.

Dysmenorrhea; Moxibustion Therapy; Moxa Stick Moxibustion; Point, Shiqizhui (EX-B 8)

Primary dysmenorrhea (PD), also called functional dysmenorrhea, is currently the most common disease in gynaecology as well as the common condition that affects women’s works and their quality of life. Treatment of primary dysmenorrhea with acupuncture-moxibustion has a long history, and it’s been regarded as a common clinical indication of acupuncturemoxibustion therapy. The efficacy and safety have been confirmed[1]. From April to December in 2012, we adopted two different moxibustion methods both with tai-yi moxa stick to treat 43 patients suffering from primary dysmenorrhea at Nanjing University of Traditional Chinese Medicine. Now, the report is given as follows.

1 Clinical Materials

1.1 Diagnostic criteria

They were based on the diagnostic criteria of primary dysmenorrhea in theObstetrics and Gynecology[2]. Abdominal pain during menstruation, without positive signs according to gynaecological examinations.

1.2 Inclusion criteria

In conformity with the diagnostic criteria of primary dysmenorrhea; aged between 18 and 30 years; regular menstrual cycle, for (28±7) d; not taking painkillers, sedatives and hormone drugs for 2 weeks before receiving this therapy; Visual analogue scale (VAS) score ≥40; willing to take part in the study and having signed the informed consent form.

1.3 Exclusion criteria

Diagnosed with secondary dysmenorrhea by the Western medicine after gynecology and B-mode ultrasonic examinations; aged below 18 or over 30 years old; pregnant and breast-feeding women; women with irregular menstrual cycle; patients who have life-threatening diseases such as cardio-cerebrovascular diseases, liver, kidney and hematopoietic diseases, mental illness and other contraindications of acupuncture-moxibustion; people who are participating in other clinical trials or patients who have already taken analgesic drugs; medical staffs who participate in this clinical study.

1.4 Statistical methods

The SPSS 19.0 version statistical software was used for statistical analyses and the test results were expressed byThe normality and homogeneity of variance of the data were tested. If the data conformed to the normal distribution and homogeneity of variance, the independent samplest-test was used for inter-group comparisons; if the data did not conform to the normal distribution or homogeneity of variance, the independent sample Mann-WhitneyUtest was used for inter-group comparisons.P＜0.05 indicated a significant difference.

1.5 General data

The subjects were students from Nanjing University of Traditional Chinese Medicine from April to December in 2012. Totally 43 patients with primary dysmenorrhea aged 18-40 years old were included and divided into two groups by the random number table according to their treatment orders. Of the 21 cases in the causalgic group, the eldest was 28 years old and the youngest was 20 years old; the longest disease duration was 12 years while the shortest was 2 years. Of the 22 cases in the tepid group, the eldest was 26 years old and the youngest was 19 years old; the longest disease duration was 12 years while the shortest was 1 year. According to the statistical analyses, there were no significant differences in age, disease duration, and VAS score (P＞0.05), indicating that the two groups were comparable (Table 1).

Table 1. Comparison of the general data between the two groups

Table 1. Comparison of the general data between the two groups

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2 Treatment Methods

2.1 Prescription and production of tai-yi moxa stick

2.1.1 Prescription

Ru Xiang(Olibanum) 20 g,Mo Yao(Myrrha) 20 g,Ren Shen(Radix Ginseng) 5 g,San Qi(Radix Notoginseng) 10 g,Qian Nian Jian(Rhizoma Homalomenae) 20 g,Zuan Di Feng(Schizophragma Integrifolium) 20 g,Rou Gui(Cortex Cinnamomi) 20 g,Hua Jiao(Fructus Zanthoxyli) 20 g,Xiao Hui Xiang(Fructus Foeniculi) 20 g,Cang Zhu(Rhizoma Atractylodis) 20 g,Fang Feng(Radix Saposhnikoviae) 80 g, andGan Cao(Radix Glycyrrhizae Preparata) 40 g.

2.1.2 Production

Twenty gram of moxa and 5 g powdered medicine were mixed and put on a piece of white cotton paper of 23 cm in length and 18 cm in width, and then rolled into a cylinder-shaped moxa stick of 2.5 cm in diameter and 15 cm in length. After that, the stick was wrapped by another piece of white cotton paper. Egg white was applied to the outside of the moxa stick for 6 times, each time after the egg white was dried in shade.

2.2 Therapeutic methods

2.2.1 Pressure

The doctors trained themselves by pressure sensor to master the pressure of 0.5 kg and 1.5 kg respectively.

2.2.2 Intervention time

The doctor should give the treatment within 1 h after the attack of dysmenorrhea.

2.2.3 Preparations before treatment

With an alcohol lamp or alcohol cotton balls, one head of the moxa stick was ignited for about 10 s. Make sure that the moxa stick was burnt evenly and let it burnt for 5-10 min till the spark went deeper into the moxa stick.

The patients were told to lie on their belly or sit to expose the lumbosacral region. Then, Shiqizhui (EX-B 8) was located and covered with a piece of cotton cloth. Inform the patients of the related issues before treatment.

2.3 Operation

2.3.1 Causalgic group

Press the ignited tai-yi moxa stick strongly (about 1.5 kg of pressure) above the cotton cloth and let the heat penetrate through the cotton cloth to the skin and the interstices of muscle. Make sure that the patients felt unbearable causalgia or try to dodge within 30 s. In this case, move away the stick within 2 s and apply again after 10 s.

The above operation was repeated for 30 min and the patients were supposed to have 40-60 times of causalgic stimulation.

2.3.2 Tepid group

Press the ignited tai-yi moxa stick gently (about 0.5 kg of pressure) above the cotton cloth and let the heat penetrate through the cotton cloth slowly to the skin and the interstices of muscle. If the patients felt causalgia or pricking pain, another two pieces of cotton cloth would be added before moxibustion again until the patients felt continuous mild stimulation.

The above operation was also repeated for 30 min.

3 Observation of Therapeutic Effect

3.1 Criterion of therapeutic effect

The patients were observed to see the improvement after one treatment. The VAS was adopted to evaluate the pain intensity. Pain degree is expressed by 0-100, 0 for no pain and 100 for the most intensive pain. The subjects were told to choose a number that can exactly represent the pain intensity according to their own feelings. The VAS scores were evaluated and recorded before moxibustion and at 10 min, 20 min and 30 min during moxibustion.

3.2 Outcome of treatment

3.2.1 Comparison of the pain degree before and after treatment

After 30-minute moxibustion treatment, the pain intensities decreased significantly in both groups compared with those of before treatment (bothP＜0.05). There was no significant difference between the two groups in the pain intensity at 30 min of treatment, but it seemed that the pain degree of the tepid group decreased rapidly during the first 10 min (Table 2).

Table 2. The changes of VAS value at different time points (point)

Table 2. The changes of VAS value at different time points (point)

Note: Compared with the result at 0 min, 1)P＜0.05

3.2.2 Comparison of VAS values during the treatment During the 30-minute treatment, the VAS values of the two groups decreased with the time of treatment (Figure 1). There were no significant differences in comparing the VAS scores between the two groups at any time points (P＞0.05).

3.2.3 Comparison of VAS D-value during the treatment Although there were no significant differences between the two groups at any time points, we can see the different pain-relief degrees during different time periods (Table 3). During the 30-minute treatment, 0-10 min was the most efficient phase of pain relief in the tepid group. However, during 10-30 min, the causalgic group had gradually outpaced the tepid group (Figure 2).

Figure 1. Line chart of the change trend of the VAS value

Table 3. The changes of VAS D-value during different periods（point）

Table 3. The changes of VAS D-value during different periods（point）

Figure 2. Line chart of changes of VAS D-value

3.2.4 Hypothetical curve of changes of patients' subjective feelings

During the 30-minute treatment, the patients had different subjective feelings. The patients in the causalgic group had the feeling of intermittent harmful stimulation, while the patients in the tepid group had the feeling of continuous mild stimulation [Figure 3, ‘0’ represents the initial temperature of skin;‘1’ represents the mild feeling (bearable); ‘2’represents the causalgic feeling (unbearable)].

Figure 3. Hypothetical curve of changes of patients’ subjective feelings

4 Discussion

4.1 Primary dysmenorrhea

Primary dysmenorrhea refers to the disease that female genital mutilation has no obvious structural change, but periodic abdominal pain or lumbosacral pain will appear before, during or after the menstrual period, even causing syncope from severe pain. Its mechanism has not been fully clarified and its cause is generally believed to be the increase of plasma prostaglandin (PG) that causes the contraction of the smooth muscle of uterine and ischemia[3]. A large number of studies found that the concentrations of PGE2and PGF2ain the endometrium and menstrual blood of patients with dysmenorrhea are significantly higher than the healthy controls, and the increase of ratio of PGF2a/PGE2leads to contractions of the smooth muscle of uterine[4]. Besides, primary dysmenorrhea maybe related to the vasopressin. The clinical research shows that the secretion of vasopressin can enhance the activity of uterine contractions, which can aggravate the symptoms of dysmenorrhea[5]. Additionally, psychological factor is probably another cause of primary dysmenorrhea.

4.2 Analysis of Shiqizhui (EX-B 8)

It’s called Shiqizhui (EX-B 8) because that it’s an extraordinary point located under the fifth lumbar vertebra. The point was initially recorded inQian Jin Yao Fang(Essential Prescriptions Worth a Thousand Gold for Emergencies) that the treatment ofZhuan Bao(dysuria due to the pressure of the fetus) with applying 50-cone moxibustion to Shiqizhui (EX-B 8). The book pointed out that moxibustion on Shiqizhui (EX-B 8) could treatZhuan Bao.Zhuan Baoand dysmenorrhea are both originated from the uterus, indicating that there should be a close connection between Shiqizhui (EX-B 8) and the uterus. Although Shiqizhui (EX-B 8) is an extraordinary point, it’s crossed by the Kidney Meridian of Foot Shaoyin, Spleen Meridian of Foot Taiyin and the Governor Vessel. Besides, the 47th chapter ofSu Wen(Plain Questions) documents that ’uterine vessels is tied to the kidney’, so moxibustion on Shiqizhui (EX-B 8) can regulate the meridian qi and warm the uterus in order to relieve pain. From the illness response, Shiqizhui (EX-B 8) has been regarded as the sensitive point of pelvic cavity, which is closed to the uterus. Therefore, moxibustion can play a role in topical treatment. Judging from the anatomical structure and physiological function of the point, Li YM, et al[6]held that the location of Shiqizhui (EX-B 8) is a transfer station for the Governor Vessel from pelvic cavity to abdominal cavity. Moreover, it is a place for yang qi to transfer from pelvic cavity to abdominal cavity and thoracic cavity. Stimulating this point can adjust the abnormal situation of yang qi of pelvic cavity, so as to treat the disease of pelvic cavity. From the neurological point of view, the fifth lumbar nerve distributes below Shiqizhui (EX-B 8) with other nerves, making up the plexus of basin and uterovaginal plexus, which spread over the genital organ. It’s believed that moxibustion on Shiqizhui (EX-B 8) can stimulate the neuroregulation mechanism to adjust the contraction of uterine muscle and eliminate the spastic contractions of the uterus in order to achieve the purpose of treating primary dysmenorrhea[6-8].

4.3 The differences between moxibustion methods of tai-yi moxa stick

Tai-yi moxa stick was first recorded inTai Yi Shen Zhen Xin Fa(Mental Methods of Tai-yi Moxa Stick)written by Han Yi-Feng from Qing Dynasty. Made of moxa mixed with medicine, it’s safe and convenient by combining the effects of both medicines and moxibustion. From Qing Dynasty till today, there havebeen prescriptions for the tai-yi moxa stick and pressing of ignited moxa stick has always been the major operation. Additionally, there are other creative ways of tai-yi moxibustion. Li XC[9]lighted both sides of tai-yi moxa stick and infixed it into the porcelain needle of the porcelain jar of 10 cm in diameter and 10 cm in height to treat the lumbar disc herniation and diabetes, which produced a good curative effect. Zhang JB, et al believed that the moxibustion has a tepid effect, and the tepid effect varies in the levels of slow, fast, strong and weak. By inheriting the basic pressing moxibustion, our research group divided the treatment into two different moxibustion methods, i.e. causalgic and tepid moxibustion. We believe that the causalgic moxibustion uses hard pressing and intermittent painful stimulation to strengthen the intensity of moxibustion stimulation, which can produce strong and fast effects. On the contrary, the tepid moxibustion uses light and continuous stimulation to stabilize the intensity of moxibustion stimulation, which can produce weak and slow effects[10]. According to the neuropathological study, the temperature sensation of the skin can be divided into four different types: cold, cool, warm and hot. However, when temperature reaches above 43 ℃ or below 15 ℃, the skin will experience a harmful temperature sensation instead of a normal one[11]. Our research group also found that patients had different subjective feelings towards the two different moxibustion methods, and thus we drew a curve to describe it (Figure 3).

4.4 The different effects of different moxibustion methods

Different moxibustion methods with tai-yi moxa stick have quite good instant analgesic effects in treating primary dysmenorrhea. From Table 2, we can see that after intervention, both groups achieved significant decreases in pain intensity. Table 3 and Figure 1 further confirm that the pain intensity was reduced gradually with the time of treatment in both groups. By Table 3 and Figure 2, we can find that the pain-relief score reached the peak in the tepid group during the first 10 min of treatment, and it then went down during the second 10 min, and then up during the last 10 min. While, in the causalgic group, the pain-relief score increased gradually. Although it’s lower than that in the tepid group for the first 10 min, it exceeded for the later 20 min of treatment. We suppose that this phenomenon should result from the adaptation time of the human body to different external stimulation. The causalgic stimulation of the causalgic group is intermittent (patients felt it insufferable), which needs body to adapt to it gradually. However, the tepid group has continuous tepid stimulation (patients enjoyed it), so the body can quickly adapt to this stimulation and thus the therapeutic effects work out faster. In addition, the differences during the last 20 min maybe related to the quantity of moxibustion stimulation, i.e. the intensity and time of moxibustion. The book ofYi Zong Jin Jian(Golden Mirror of Medicine) records that‘no matter what the disease is, fire and qi must be sufficient and then people can be cured’. The insufficient quantity of stimulation of moxibustion can’t reach a certain curative effect. Zhang QF thought that the intensity of moxibustion, quantity of moxibustion stimulation and time of moxibustion should be closely connected, which can be illustrated by the following formula.

Intensity of moxibustion (Quantity of moxibustion stimulation) ＝ Stimulation intensity of moxibustion × Stimulation time of moxibustion)[12].

We can know from the formula that the quantity of stimulation of moxibustion is proportional to the stimulation intensity of moxibustion and stimulation time of moxibustion. That is to say, when the stimulation time is constant, the stronger the stimulation intensity, the larger the quantity of moxibustion stimulation, and vice versa. In this study, both groups received 30-minute treatments, but the causalgic group was intervened by a harder pressure (about 1.5 kg) and intermittent pain-causing stimulation. In this case, the quantity of moxibustion stimulation in the causalgic group is higher than that in the tepid group. Therefore, after the body gradually adapts to the causalgia, the pain-relief score of the causalgic group gradually surpasses that of the tepid group.

5 Conclusion

This study results showed that the two different moxibustion methods of tai-yi moxa stick have good instant analgesic effects in treating primary dysmenorrhea. Generally speaking, for the primary dysmenorrhea patients, if 30 min is regarded as the treatment time, tepid moxibustio stimulation is suggested to be used for the first 10 min, so that the patients can adapt to the thermal stimulation. The causalgic moxibustion stimulation is suggested to be used for the last 20 min to increase the quantity of moxibustion stimulation to reach better therapeutic effects. Certainly, doctors should know the patient’s condition well and then use the two different moxibustion methods flexibly. For patients who have acute dysmenorrhea or with higher VAS scores, the doctor should stick to the principle that ’to treat the symptoms for acute conditions’. In this sense, the first choice should be causalgic stimulation, since it canachieve a fast and strong effect to relieve the symptoms. On the contrary, for patient who suffer from chronic dysmenorrhea or with lower VAS scores, the doctor should stick to the principle that ’to treat the root for chronic conditions’. In this way, the first choice should tepid stimulation, since it can approach a mild and slow tepid effect to cure the disease. In conclusion, both of the two moxibustion methods have their advantages and disadvantages. The doctors should make the best of them and adopt them flexibly in clinic in order to achieve the best therapeutic effects.

Conflict of Interest

The authors declare that there was no conflict of interest.

Acknowledgments

Thank for the support of Project of Natural Science Foundation of China (No. 81373750); Undergraduate Innovation Training Program of Jiangsu Province (No. 2012JSSPITP1140).

Statement of Informed Consent

All the parents signed the informed consent.

[1] Yang JH, Li P. Survey and thinking about clinical treatment of primary dysmenorrhea by acupuncture and moxibustion in recent years. Zhongguo Zhenjiu, 2004, 24(5): 364-366.

[2] Le J. Obstetrics and Gynecology. Beijing: People’s Medical Publishing House, 2008: 318-319.

[3] Lefebvre G, Pinsonneault O, Antao V, Black A, Burnett M, Feldman K, Lea R, Robert M. Primary dysmenorrhea consensus guideline. J Obstet Gynaecol Can, 2005, 27(12): 1117-1146.

[4] Bingfer JR. Primary dysmenorrhea treatment with prostaglandin inhibitors: a review. Am J Obstet Gynecol, 1981, 140(8): 874-879.

[5] Ming HX, Qiu T, Su Y. Advance in primarily dysmenorrhea: pathogenesis and treatment. Gansu Zhongyi Xueyuan Xuebao, 2004, 21(1): 55-57.

[6] Chen SZ, Hou WJ, Zhang BF, Bu YQ, Gao SZ. Observations on the analgesic time-effect regularity of acupuncture only at Shiqizhui (Extra 18) in primary dysmenorrheal patients. Shanghai Zhenjiu Zazhi, 2009, 28(12): 689-690.

[7] Li YM, Bu YQ, Hou WJ, Chen SZ, Gao SZ. Observation on immediate analgesic effect of acupuncture at Shiqizhui (EX-B 8) only or multi-acupoints in patients with dysmenorrhea: a randomized controlled trial. Zhongguo Zhenjiu, 2011, 31(3): 199-202.

[8] Chen SZ, Hou WJ, Cong Q. Comparison of the analgesic time-effect regularities of acupuncture at a single point and at multiple points in treating dysmenorrhea. Shanghai Zhenjiu Zazhi, 2010, 29(10): 623-625.

[9] Li XC. The inheritance and innovation of tai-yi moxa stick. Dajia Jiankang, 2012, 6(8): 63-64.

[10] Zhang JB, Wang LL, Wu HG, Hu L, Chang XR, Song XG, Ma XP. Theory study: warming-dredging and warmingreinforcing of moxibustion. Zhongguo Zhenjiu, 2012, 32(11): 1000-1002.

[11] Han JS. Neuroscience. Beijing: Peking University Medical Press, 2009: 676-680.

[12] Zhang QF. Effects of stimulation intensity on reinforcing and reducing in moxibustion. Fujian Zhongyi Xueyuan Xuebao, 2002, 12(1): 45-47.

Zhang Jian-bin, M.D., associate professor.

E-mail: zhangjianbin@njutcm.edu.cn

R246.3

: A

Date:October 8, 2013