Despite the recent progress in physiological studies of acupuncture, few morphological studies from the viewpoint that acupuncture stimulation produces with a small tissue injury have been reported. In this study, we evaluated the mechanism of acupuncture stimulation by a histopathological approach. First, we confirmed the tissue structure from the skin to the muscle layer in a corpse. In the human body, free terminals (endings) of unmyelinated nerve fibers (1.5μmin diameter, Group III or Group IV) were present subcutaneously or in the endomysium of muscle tissues. Next, the extent of tissue injury caused by insertion of needles 0.20-0.95mm in diameter evaluated in human and animal tissues. The extent of the injury was in proportional to the diameter of the needle. These confirmed that acupuncture stimulation is clearly a small tissue injury. Also, the free terminals (endings) of unmyelinated nerves similar to those observe in the human tissue were obsurved in the endmysium near the injury site. These morphological findings suggest that acupuncture stimulation is related to Group III or Group IV fibers.

Recently, magnetic resonance imaging (MRI) has brought significant advancements in the diagnosis of spinal disorders. But there is much debate about the abnormalities detected by MRI clinically. In this study, we try to clarify the correlation between spinal abnormalities detected by MRI and physical signs in 45 patients with neck, shoulder, and low back pain. Physical signs were segmental sensory disturbance, amyotrophy, and radicular pain, and the abnormalities of MRI were bulging, protrution, extrution, and osteophytes. MRI showed a symptomatic change, that is a false positive (abnormality of MRI^* (+), physical sign^** (-)), in 26 of the 45 patients (57.7%), a true positive (+, ^**+) in 15 of 45 patients (31.1%), a true negative (^*+, ^**-) in the remaining 5 patients (11.1%).
These results suggested that the physical signs are more important than the abnormalities of MRI in patients with neck, shoulder and low back pain. We think that the acupuncture therapist should carry out a more detailed physical examination of the patients clinically.

[Objective]Traumatic pneumothorax in acupuncture treatment should be avoided. This study was designed to detect the safe depth of the thoracic area with acupuncture and was compared with other studies in the past.
[Methods]The Subjects were 187 cases, male: 90, female: 97, mean age: 67.8 (min-max: 23-91) and classified into 3groups (thin, normal, fatty) from BMI. MultiCT images were filmed in 3anatomical levels (the tracheal point (TP), scapular point (SP), shortest point (MsP) of the thoracic area and the distance between the skin and lung tissue on the display was measured (Osirixver3. statistics:ANOVA).
[Results]The distance between the skin and lung tissue were, average ±SD, TP 3.01 ± 0.79, SP 2.34 ± 0.65, MsP 2.14 ± 0.61 cm. The longest distance was 5.5 cm (TP), and the shortest was 0.9 cm (MsP). The differences between the body depths and TP and SP, and MsP were statistically significant (TP >SP >MsP). There was a positive correlation between BMI and body depth, and a negative correlation between age and body depth. From an anatomical point of view, TP seemed to coincide with BL38, SP seemed to coincide with BL40, and MsP seemed to coincide with BL41 or BL42.
[Conclusions]MultiCT was very useful for a measurement of the distance between skin and lung tissue scientifically. The results of this study were almost in agreement with other studies in the past. The results are informative in showing that the risk of traumatic pneumothorax might be reduced clinically. But it is too difficult to confirm what is a safe depth, and it is recommended to measure the body depth under the conditions that include clinical problems, for example, the positioning in the treatment of acupuncture. The concept of safe depth should be changed to a dangerous depth with acupuncture treatment.

Aim : Since it was reported that acupuncture at Danchu (CV17) was critical when the needle penetrated through the congenital sternal foramen, we decided to study the incidence of the congenital sternal foramen, as well as the distance between the body surface and the back side of the sternum at Danchu, in order to know the safe depth of acupuncture penetration.
Method : 1) We selected 51 cadavers to examine the incidence of congenital sternal foramen and, if any, to study its structure. We also selected 21 cadavers to measure the cadaveric thickness of the sternum. 2) We selected 31 people to measure the incidence of the congenital sternal foramen and the distancebetween the body surface and the back side of the sternum at the point of Danchu.
Results : 1) We found one out of 51 cadavers which had congenital sternal foramen. The location of the foramen was at the height of the fourth intercostal space. It was round-shaped, 9mm in diameter, and filled with hard connective tissue. The thickness of the sternum ranged from 9 to 15mm with an average of 11.5 ± 2mm. 2) There was no one who had the congenital sternal foramen among the 32 people. The distance between the body surface and the back side of the sternum ranged from 11 to 31mm with an average of 18.8 ± 5mm.
Conclusion; 1) The incidence of the congenital sternal foramen in this study was one in 51 cadavers and zero in 32 people. 2) We concluded that acupuncture at Danchu within a depth of 10mm is sufficiently, even if congenital sternal foramen exists.

Acupuncture to Gaohuang carries a risk of causing pneumothorax because it reaches the lungs at deep portion. This study was designed to consider a safe depth for acupuncture to Gaohuang.
1) We inserted a needle to Gaohuang on both sides of a cadaver to examine the location of the needle tip and measure the distance from the body surface of the left Gaohuang to the pleura. The tip was located at the fifth intercostal region on both sides, and the distance was 44 mm with a rib thickness of 10 mm. 2) Using 104 students, we inserted a needle to the left Gaohuang until the tip reached the rib, and measured the distance between the bodysurface and rib. The minimal distance was 14 mm. 3) We inserted a needle to Gaohuang on both sides of two males and took CT-radiographs to examine the location of the needle tip and measure the distance from the body surface of Gaohuang to the pleura. In a man of standard body size, the needle reached the rib on the left and the intercostal region on the right. The thickness of the left rib was 10.9 mm, and the distance from body surface to pleura was 33.6 mm on the left and 28.4 mm on the right. In a man of thin body size, the needle reached the rib on both sides, with the rib thickness was 9.8 mm on the left and 8.8 mm on the right. The distance from body surface to pleura was 29.4 mm on the left and 31.8 mm on the right. The above results showed that needle insertion within 19 mm (the minimal value of the measured distance between the body surface and rib + the half thickness of the rib) is safe.

Six members of the Research Committee for the Meridian Point (former Committee for the Meridian Point) reported on three themes regarding meridian and acupuncture point at Workshop II of the 54th Science Rally of The Japan Society of Acupuncture and Moxibustion held in Fukuoka.
1st theme : Anatomical examination of the meridian and meridian point.
1) Anatomic structure showing path and meridian running. (Kenji Matsuoka) : Similarity of meridian pathway and course of nerve and blood vessels in cadaver.
2) Gross anatomical study of meridian and acupuncture point in upper limbs (Kansho Yamada) : Doctoral study of Katsuyosi Toyoda, former Nagoya City University School of Medicine researcher and Yamada's study (Relation between running of meridian & acupuncture point and subdermal nerve & blood vessels) were reported.
2nd theme : Study of acupuncture safety depth in Japan and China.
1) Research and progress situation of acupuncture safety depth in China. (WANG Cai Yuan) : Data of Yan Zhenguo, professor of anatomy at Shanghai University of Traditional Chinese Medicine, an authority on the study of acupuncture safety depth and progress situation of recent study of acupuncture safety depth in China.
2) Retrospective study of acupuncture safety depth (Tomofumi Ozaki) : Study of acupuncture safety depth published by Ozaki to date and comparative study alongside Prof. Yan Zhenguo data.
3rd theme : Examination of clinical effect of a few meridian points.
1) Acupuncture clinical effect using a few meridian points (Syunji Sakaguchi) : Paper research and analysis of acupuncture clinical effects using 1-4 meridian points of Japana Centra Revuo Medicina.
2) Inflence on skin energizing current by various acupuncture stimulation of LI4 (Gokoku) (Kazuhiro Morikawa) : Influence on the amount of skin energizing current by acupuncture stimulation, direct current electricity stimulation and stimulation of electroacupuncture to LI4.