Acupuncture Extra Point Pigen (EX-B4)
Location:
Lie pronely; between spinous processes of the 1st and 2nd lumbar vertebra, 3.5 cun lateral to the posterior median line. Or, 0.5 cun lateral to Huangmen (BL51) point ( B 51 ).

Function:
Relieving the distension and regulating qi.

Regional Anatomy:
Skin-subcutaneous tissue-latissimus muscle of back-inferior posterior serratus muscle-iliocostal muscle.
In the superficial layer, there are the lateral cutaneous branches of the posterior btanch of the 12th thoracic nerve and the accompanying arteryand vein. In the deep layer, there are the muscular branches of the posterior branch of the 12th thoracic nerve.

Indications:
Hepatosplenomegaly, hepatitis, gastroenteritis, gastrectasia, gastrospasm, and lumbar pain.

Methods:
Insert the needle perpendicularly to 1-1.5 cun deep; moxibustion: using 7-15 moxa-cones, or mild moxibustion for 30 min.
Note:
Don`t puncture deeply toward the anterior side, or else the needle would penetrate the quadrate muscle of loins-the pararenal adipose body-the renal fascia-the adipose capsule of kidney-the renal fibrous membrane-the kidney and injure the kidney tissue.