Acupuncture Point Gongsun (SP4)
Location:
Upright sitting with drooping feet or supine position; posterior to the medial side of the great toe, at the medial side of the base of the 1st metatarsal bone antero-inferiorly, 1 cun apart from Taibai(SP3) Shu-Stream, Yuan-Primary Point ( Taibai(SP3) Shu-Stream, Yuan-Primary Point ).

Function:
Strengthening the spleen and stomach, and regulating Chong and CV channels.

Regional Anatomy:
Skin-subcutaneous tissue-abductor muscle of great toe-short flexor muscle of great toe-tendon of long flexor muscle of great toe.
In the superficial layer, there are the medial branches of the foot from saphenous nerve and the tributaries of the dorsal venous arch of the foot. In the deep layer, there are the branches or tributaries of the medial plantar artery and vein and the branches of the medial plantar nerve.

Indications:
Gastric pain, vomiting, abdominal pain and distension, Diarrhea, dysentery, and borborygmus.

Prescription:
Combined use with Xuanzhong (GB 39) Influential Point of the Marrow) for treatment of arthritis of ankle joint; with Neiguan (PC6) Luo-Connecting Point the Eight Confluent Point) for treatment of stomach-ache; with Zusanli (ST 36) He-Sea Point) for treatment of gastritis and gastric ulcer; and with Zusanli (ST 36) and Shenmai (BL62) The Eight Confluent Point) for treatment of flacidity of the lower limbs.

Methods:
Insert the needle perpendicularly 0.5-1.0 cun deep; needling response: local sensation of distension; moxibustion : 3-5 moxa-cones, mild moxibustion for 10 min.