中渚 : Zhongzhu : Central Islet

Classifications:

Shu-Stream and Wood point
Mother point of the Sanjiao channel

Trigger point (Travell & Simons, 1998, Trigger Point Manual)

Location:

On the dorsum of the hand, in the depression just proximal to the fourth and fifth metacarpo-phalangeal joints. Locate with the hand resting in a loose fist. May also be located as the apex of an equilateral triangle formed by this point the prominences of the metacarpo-phalangeal joints of the little and ring fingers.

Needling:

Perpendicular or oblique insertion directed proximally, 0.5 - 1 cun

Classical Needling:

"The Shaoyang usually has little Blood and much Qi" (Su Wen 素問 ch. 24) implying this channel should normally be needled.
"The hand Yin and Yang receive their Qi via nearby paths so their Qi arrive swiftly. The depth of piercing must not exceed 2 fen and must not remain inserted for longer than one exhalation" (Ling Shu 靈樞 ch. 12).
"It is needled to a depth of twofen, (the needle) is retained for a duration of three exhalations, and it is moxaed with three cones" (Huangfu Mi 皇甫謐, 3rd Century, Zhenjiu Jiayi Jing 針灸甲乙經).

TCM Actions:

Clears Heat
Benefits the ears
Clears the head and eyes
Activates the channel and alleviates pain

TCM Indications:

• Tinnitus, deafness, earache, one-sided headache, pain of the temples, dizziness, redness and pain of the eyes, Superficial Visual Obstruction, Throat Painful Obstruction (喉痹, Hou Bi).
  
• Itching of the body and face, red face, red face with absence of sweating, febrile disease, febrile disease with headache, chills and fever, aversion to wind and cold, chronic Malarial (瘧, Nue) Disorders, mania.
  
• Inability to flex and extend the fingers, redness, swelling and pain of the elbow and upper arm extending into the shoulder, numbness of the four limbs, pain of the spine at the level of the Heart.

I Ching Hexagram:

䷩ Yi 益 Increase, augment

Shared with Zhongchong Pc-9. Balanced by ䷟ (Zhongdu Liv-6 or Waiqiu GB-36).

Hexagram attributions are my own with an explanation given in the glossary.

Neuroanatomy:

Superficial Innervation: Ulnar nerve from C8 and T1

Dermatome Segment: C7, C8

Trigger Point Associations:

Muscle:
Fourth dorsal interosseous

Location Notes:
Together with ulnar Yaotongxue. Trigger points for the other interossei may be found anywhere between the metacarpals

Pain Referral Pattern:
To side of affected finger

Indications:
Arthritic pain in the fingers ; Heberden's nodes

Martial Applications & Effects of Injury:

In seizing martial arts (Qin Na) this point is a cavity pressing point (Dian Xue, 點穴). Pressing this cavity can cause pain or numbness, or even shock the brain to make the opponent pass out (Yang, 2004, Analysis of Shaolin Chin Na, 2nd Edition).

See Montaigue, Dim Mak Locations, Taijiworld.com for explanation of effects.

Major Combinations:

• Deafness:
    Zhongzhu SJ-3 with Waiguan SJ-5, Erheliao SJ-22, Tinghui GB-2, Tinggong SI-19, Hegu LI-4, Shangyang LI-1 and Zhongchong Pc-9
    (Xu Jun, 許浚, 1611: Dong Yi Bao Jian, 東醫寶鑑, Precious Mirror of Oriental Medicine).
  
  
• Deafness and tinnitus:
    Zhongzhu SJ-3 with Tianrong SI-17, Tinggong SI-19 and Tinghui GB-2
    (Sun Simiao, 孫思邈, 625: Bei Ji Qian Jin Yao Fang, 備急千金要方, Essential Prescriptions Worth A Thousand Gold).
  
  
• Tinnitus:
    Zhongzhu SJ-3 with Yemen SJ-2, Tinggong SI-19, Tinghui GB-2, Ermen SJ-21, Baihui Du-20, Luoque Bl-8, Yangxi LI-5, Qiangu SI-2, Houxi SI-3, Wangu SI-4, Shangyang LI-1 and Shenshu Bl-23
    (Great Compnedium).
  
  
• Ear pain, deafness and tinnitus:
    Zhongzhu SJ-3 with Guanchong SJ-1, Yemen SJ-2, Tianchuang SI-16 and Yangxi LI-5
    (Sun Simiao, 孫思邈, 625: Bei Ji Qian Jin Yao Fang, 備急千金要方, Essential Prescriptions Worth A Thousand Gold).
  
  
• Visual Dizziness:
    Zhongzhu SJ-3 with Toulinqi GB-15
    (Wang Zhizhong, 王執中, 1220: Zhen Jiu Zi Sheng Jing, 針灸資生經, Classic of Supporting Life with Acupuncture and Moxibustion).
  
  
• Throat pain:
    Zhongzhu SJ-3 with Zhigou SJ-6 and Neiting St-44
    (Sun Simiao, 孫思邈, 625: Bei Ji Qian Jin Yao Fang, 備急千金要方, Essential Prescriptions Worth A Thousand Gold).
  
  
• Swelling of the throat:
    Zhongzhu SJ-3 with Taixi Kid-3
    (Wang Zhizhong, 王執中, 1220: Zhen Jiu Zi Sheng Jing, 針灸資生經, Classic of Supporting Life with Acupuncture and Moxibustion).
  
  
• Chronic Nue (Malaria):
    Zhongzhu SJ-3 with Shangyang LI-1 and Qiuxu GB-40
    (Yang Jizhou, 杨继洲, 1601: Zhen Jiu Da Cheng, 針灸大成, Great Compendium of Acupuncture and Moxibustion).
  
  
• Nue (Malaria) with generalised fever:
    Zhongzhu SJ-3 with Yindu Kid-19, Shaohai He-3, Shangyang LI-1 and Sanjian LI-3
    (Wang Zhizhong, 王執中, 1220: Zhen Jiu Zi Sheng Jing, 針灸資生經, Classic of Supporting Life with Acupuncture and Moxibustion).
  
  
• Inability to bend the elbow and fingers:
    Zhongzhu SJ-3 with Waiguan SJ-5, Quchi LI-11 and Shousanli LI-10
    (Yang Jizhou, 杨继洲, 1601: Zhen Jiu Da Cheng, 針灸大成, Great Compendium of Acupuncture and Moxibustion).
  
  
• Pain of the elbows, at times cold:
    Zhongzhu SJ-3 with Guanchong SJ-1, Quchi LI-11, Shousanli LI-10, Yanggu LI-5 and Chize Lu-5
    (Sun Simiao, 孫思邈, 625: Bei Ji Qian Jin Yao Fang, 備急千金要方, Essential Prescriptions Worth A Thousand Gold).
  
  
• Contraction of the five fingers with inability to flex and extend:
    Guanchong SJ-1 with Wangu SI-4
    (Sun Simiao, 孫思邈, 625: Bei Ji Qian Jin Yao Fang, 備急千金要方, Essential Prescriptions Worth A Thousand Gold).

Notes:

In five element acupuncture this point is reinforced to tonify San Jiao deficiencies.

Being the Wood point of the San Jiao channel it is also indicated in TCM for subduing Wind and Heat patterns emanating from the Wood organs of Liver and Gallbladder.

This apparent contradiction in functions can be resolved by considering the function of the San Jiao as like a water cooling system, taking Heat out of the body through the water and transmitting to the Kidneys/Bladder for excretion. Therefore deficiency in this system can enable Heat to accumulate and in turn generate Fire and Wind. Reinforcing the San Jiao therefore improves its ability to drain Wind and Fire from the body.

Ling Shu Ch. 19, on the Four Seasonal Qi, advises using the Shu-Stream points, unless the diseases are in the Fu organs, in which case the He-Sea points are chosen.

Cecil-Sterman explains that combining the Shu-Stream and Jing-Well points directed outwards is a method of expelling Pathogens from the Shaoyang.

In Tung acupuncture this point equates to the Zhong Bai, Middle White, point indicated for Kidney deficiency patterns, often combined with the Da Bai and Ling Gu points (Sanjian LI-3 and proximal to Hegu LI-4) for lumbago (Chu, 2015).

One explanation for this could relate to the five element attribution of this point as the tonifying/mother point of the San Jiao channel and the San Jiao's close relationship to the Kidneys and the balancing of Water and Fire.

In Mayan medicine:
Commonly used for pain in the hand and arm, up to the elbow (Garcia, Sierra, Balam, 1999: Wind in the Blood)

Medieval phlebotomy point (John de Foxton, 1408: Liber Cosmographiae, maa.cam.ac.uk; Hans von Gersdorff, 1517: Feldtbüch der Wundartzney, www.nlm.nih.gov)

In Tibetan medicine:
Moxa point (AMNH, Tibetan Medical Paintings)

In Thai massage:
Acupressure point indicated for headache, sciatica and shoulder pain/injury/arthritis (Salguero & Roylance, 2011, Encyclopedia of Thai Massage)

Reference Notes:

Basic information on location, needle depth, TCM actions, indications and combinations is taken from Deadman et al (2001): A Manual of Acupuncture with additional anatomical information researched by reference to Gray's Anatomy (38th Ed., 1995) unless otherwise referenced. Images were found on acupunctureschoolonline.com and can be traced back to Claudia Focks (2008) Atlas of Acupuncture originally. I cannot claim any credit or rights over them. Other sources should be quoted in the text.

For some of the more unusual terms I have created a glossary here