二間 : Erjian : Second Space

Location Guides:

Classifications:

Ying-Spring and Water point
Child point of the Large Intestine channel
One of the "59 piercings" for clearing Heat in Ling Shu Ch. 23

Location:

On the radial border of the index finger, in a depression just distal to the metacarpo-phalangeal joint

Needling:

Oblique proximal or disal insertion 0.2 - 0.3 cun or perpendicular-oblique insertion towards the palm 0.5 cun

Classical Needling:

"The Yangming usually has much Qi and much Blood" (Su Wen 素問 ch. 24) implying this channel can normally be needled or bled.
"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 three fen, (the needle) is retained for a duration of six 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:

Expels Wind, clears Heat and reduces swelling
Alleviates pain

TCM Indications:

• Toothache, pain and swelling of the lower cheek, acute weeping eczema of the face, deviation of the mouth and eye, nosebleed, rhinitis, Throat Painful Obstruction (喉痹, Hou Bi), dry mouth, cloudy vision, eye diseases, yellow eyes.
  
• Febrile disease, cold shivering, acute food stagnation.
  
• Injury by cold with water binding the chest and lateral costal region, propensity to fright, somnolence.
  
• Pain and stiffness of the shoulder and back, cold pain at the point Jianyu L.I.-15.

I Ching Hexagram:

䷮ Kun 困 Oppression

Shared with Chize Lu-5. Balanced by ䷕ (Jiexi St-41 or Dadu Sp-2).

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

Neuroanatomy:

Superficial Innervation: Median nerve branch to fingers from C6 - C8

Dermatome Segment: C7

Martial Applications & Effects of Injury:

Combined with Yangxi LI-5 grasping and digging a finger into these two points can cause knock out but due to the location is not a realistic point to use (Montaigue, Dim Mak Locations, Taijiworld.com).

Major Combinations:

• Toothache and lumbar pain accompanied by Throat Painful Obstruction:
    Erjian LI-2 with Yangxi LI-5
    (Xi-Hong Fu, 席弘賦, Ode of Xi-Hong. First recorded in: Xu Feng, 徐鳳, 1439: Zhen Jiu Da Quan, 針灸大全, Complete Collection of Acupuncture and Moxibustion).
  
  
• Toothache of the lower jaw:
    Erjian LI-2 with with Shanyang LI-1, Yanggu SI-5, Yemen SJ-2 and Sidu SJ-9
    (Sun Simiao, 孫思邈, 625: Bei Ji Qian Jin Yao Fang, 備急千金要方, Essential Prescriptions Worth A Thousand Gold).
  
  
• Toothache:
    Erjian LI-2 with Quanliao SI-18
    (Haungfu Mi, 皇甫謐, 282: Zhen Jiu Jia Yi Jing, 針灸甲乙經, Systematic Classic of Acupuncture and Moxibustion).
  
  
• Rhinitis with nosebleed:
    Erjian LI-2 with Yinxiang LI-20 and Fengdu Du-16
    (Yang Jizhou, 杨继洲, 1601: Zhen Jiu Da Cheng, 針灸大成, Great Compendium of Acupuncture and Moxibustion).
  
  
• Pain of the eye:
    Erjian LI-2 with Yangxi LI-15, Daling Pc-7, Sanjian LI-3, Qiangu SI-2 and Shanxing Du-23
    (Yang Jizhou, 杨继洲, 1601: Zhen Jiu Da Cheng, 針灸大成, Great Compendium of Acupuncture and Moxibustion).
  
  
• Somnolence:
    Erjian LI-2 with , Shouwuli LI-13, Taixi Kid-3, Dazhong Kid-4 and Zhaohai Kid-6
    (Wang Zhizhong, 王執中, 1220: Zhen Jiu Zi Sheng Jing, 針灸資生經, Classic of Supporting Life with Acupuncture and Moxibustion).
  
  
• Somnolence:
    Erjian LI-2 with Sanjian SI-3, Taixi Kid-3, Zhaohai Kid-6, Baihui Du-20, Tianjing SJ-10, Lidui St-45 and Ganshu Bl-18
    (Yang Jizhou, 杨继洲, 1601: Zhen Jiu Da Cheng, 針灸大成, Great Compendium of Acupuncture and Moxibustion).
  
  
• Excessive fright:
    Erjian LI-2 with Yinxi He-6, Jianshi Pc-5 and Lidui St-45
    (Wang Zhizhong, 王執中, 1220: Zhen Jiu Zi Sheng Jing, 針灸資生經, Classic of Supporting Life with Acupuncture and Moxibustion).

Notes:

In five element acupuncture this point is reduced to drain excess in the Large Intestine.

Ling Shu Ch. 19, on the Four Seasonal Qi, advises selecting the Jing-Well and Ying-Spring openings in winter, piercing deeply and retaining for a while. However, the character for "retain" 留 is a combination of 田 "a field," possibly referring to the idea of waiting for things to grow, and 卯 which is the 4^th Earthly Branch (Mao, Rabbit, ䷡, 5-7 am, Large Intestine) and said to derive from a Shang Dynasty glyph, originally referring to a blood sacrifice (a person or animal cut in half) before coming to mean bloodletting and "pouring out" (Smith, 2011). This might suggest it was actually referring to bleeding these points, and maybe even letting the points bleed for a time rather than retaining the needle.

Ling Shu Ch. 23, On Heat Diseases, gives a different list of points for the "59 Piercings" to Su Wen Ch. 61. They include three on the outer and three on the inner side of the hands which most likely includes this point.

In Tung acupuncture a pair of points called Mu Xue, Wood Point, are located on the palmar-ulnar aspect of the proximal segment of the index finger. They are at 1/3 and 2/3 of the distance from the proximal crease. They are indicated for Liver Yang rising signs such as tinnitus, shoulder and neck pain stiffness or pain, hyperlipidemia and bitter taste in the mouth, especially if combined with Liver points (Chu, 2015).

In the Maoshan Daoist tradition, when the 12 earthly branches, I Ching trigrams and elements are mapped onto the hand this section of the finger equates to the branch 卯 Mao, the Trigram ☲ Li, Fire and the element of Earth. The middle segment of the finger relates to the branch 辰 Chen, the Trigram ☶ Gen, Mountain and the element of Earth (Read, 2020, FB Post; 17QQ.com, 2020, Eight trigrams and twelve Branches of the earth palm).

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