Deng Aimin, Chinese Medical Aid Team in Morocco Shanghai Pudong Hospital
Keywords: channels and network vessels, acupuncture point, Dubi [ST-35]
The two points known as “Du Bi” or Xi Yan, are located medially and laterally at the lower border of the patella, and are important points used clinically to treat various knee joint issues. They course the channels and unblock the network vessels, resolve spasms, and alleviate pain. They have a noticeable effect on acute and chronic pathological changes to the knee joint when there are symptoms such as swelling, pain, numbness, and loss of function. Most historical literature on acupuncture considers the medial Du Bi to be an extraordinary point, while lateral Du Bi is classified as belonging to the yangming stomach channel. Modern acupuncture texts, including the Acupuncture Point Wall Chart that was reviewed and published by People’s Publishing House, are all in agreement with this view. However, in light of the theoretical principles regarding the channels and properties of points in Chinese medicine, and considering the indications, functions, and effects of this point in clinical practice, this position is open to discussion.
In TCM theory it is believed that “the hundred bones of the human body, the joints of its four limbs, the five viscera and six bowels, above and below, and the interior and exterior all are connected to each other by the channels and network vessels, and all are covered with points” . Among these, the points belonging to the twelve channels as well as the Ren Mai and Du Mai are called “channel points”, while the others are categorized as “extraordinary points” . However, the discovery and categorization of points on the channels and network vessels, the generalization and verification of their functions and indications, and the summarization and enhancement of theoretical knowledge is not set in stone, and this knowledge has undergone a long process of development and refinement. Taking the point Gao Huang Shu [BL-43] as an example, it was originally classified as a non-channel ex- traordinary point used for moxibustion. Because of its remarkable therapeutic effects, it was described in detail by Tang-dynasty doctors in Qian Jin Fang [Thousand Gold Pieces Prescriptions] and Qian Jin Yi Fang[Thousand Gold Pieces Supplemental Prescriptions]. Late Song-dynasty works such as Tongren Shuxue Zhenjiu Tujing [Illustrated Manual of Acupuncture Points of the Bronze Figure] listed it as part of the foot taiyang [greater yang] bladder channel, thus making it a channel point. Meanwhile, some extraordinary points, such as Taiyang and Fengshi [GB-31] have overshadowed the original channel points located nearby in terms of clinical application due to their convenient locations and remarkable effects. This shows that the attributions of channel points and extraordinary points are not only not set in stone, but are also not determined by their degree of therapeutic effect.
Discussions of the therapeutic functions of channels, network vessels, and points in the Huang Di Nei Jing point out that “that which a channel or network vessel passes through is that which is covered by the indications [for that channel or vessel]” . This is to say that, aside from treating local pathological changes, channel points more importantly can treat the areas their channel reaches and related pathological changes in the corresponding organ. For instance, He Gu [LI-4] may be needled for toothache, Hou Xi [KD- 3] may be used for stiff neck, Kong Zui [LU-6] can subdue cough and wheezing, and Shao Shang [LU-11] disperses throat illnesses. All of these reflect the special function of channel points to treat areas reached by their channels and pathological changes in associated organs. This is the theoreti- cal basis for choosing points on the lower body to treat the upper body, choosing points on the right to treat the left, and on the left to treat the right in the clinical practice of acupuncture. It is also an important principle for formulating local and distal point selections.
Returning to extraordinary points, although they are effective in treating local pathological changes, they do not have the function of treating distal ones. Although there are a few extraordinary points, such as Yao Tong Xue on the back of the hand or Xue Ya Dian [Blood Pressure Point] located 0.5 cun lateral to the transverse process of the sixth cervical vertebra, that have the theoretical effects of treating lumbar pain and lowering blood pressure, respectively, their effects are not notable in clinical practice and have not received much attention from doctors. In short, channel points have comprehensive therapeutic effects, while extraordinary points’ effects are limited to the local area. This is the key to differentiating channel points from extraordinary points.
From this it can be seen that lateral Dubi obviously does not fit the standards for a channel point. Xue Hai [SP- 10], located on the medial side of the knee joint, harmonizes the construction and clears heat. It can treat func-tional uterine bleeding, urticaria, and flooding and spotting. Wei Zhong [BL- 40] located behind the knee joint drains heat and fortifies the lumbar area, and has a clear effect in treating summer-heat stroke and lumbar sprain. Moreover, both Zu San Li [ST-36], known for its association with the stomach and abdomen, and Shang Ju Xu [ST-37] are located near lateral Du Bi on the foot yangming stomach channel. These points regulate the stomach and fortify the spleen, adjust qi and tonify blood, clear heat and transform dampness, harmonize the middle and unblock stagnation. These comprehen- sive actions make these two points important for treating illnesses of the stomach and intestinal tract. In contrast, aside from lateral Du Bi’s local action of treating pathological knee joint changes, there are no records in the literature that report on its functions in treating other distal pathological changes. Therefore, both lateral and medial Du Bi should be classified as extraordinary points and not channel points.
The channel attributes of points are a summary of long-term medical experience and, more importantly, are an important basis guiding clinical point selection. This essay represents one perspective on this issue and is intended to start a discussion in the hopes that experts will contribute their suggestions.
