Course
This channel commences from the tuner canthus, ascends to the forehead and joins its symmetrical channel at the vertex (Point Baihui. DU20).
One of its branches splits off the vertex and goes to the upper aspecl of the" auricle.
The original channel leaves the vertex for the brain where it re-emerges and runs downward to the back of the neck. Continuing along the medial side of the scapula, it travels parallel to the vertebral column and reaches the lumbar region Passing the paravertehral muscles, it communicates with the kidney and enters into its pertaining organ,the urinary bladder.
The branch from the lumbar region runs downwards parallel to the vertebral column (1.5 individual cun lateral to the back mid-line). through the gluteal region. and into the popliteal fossa.
Another branch emerges from the original channel at the back of the neck. from the medial side of the scapula passes through the scapula, and runs down-parallel to the vertebral column (3 cun lateral to the back mid-line).Then
it runs through the trochanrer major of the femur, downwards along the posterior border of the lateral side of the thigh where it meets the branch descending from the lumbar region in the popliteal fossa. From there, it makes its way down through the muscutus gastrocnemius, emerges from the posterior aspect of the external malleolus, runs along Poinr Jinggu(BL64)to the lateral side of the tip of the small toe (Point Zhiyin, BL67), where it connects with the Kidney Channel of Foot-Shaoyin.

Shangliao(BL31)
Location:On the sacrum ,at the midpoint between the posterosuperior iliac spine and the posterior midline,just at the 1st posterior sacral foramen.
Indications:Lumbago,dysuria and dysphoria,irregular menstruation,abnormal vaginal discharge,prolapse of uterus.
Method: Puncture perpendicularly 0.8-1.2 inches. Moxibustion is applicable.
Regional anatomy
Vasculature: The posterior branches of the lateral sacral artery and vein.
Innervation: At the site where the posterior ramus of the first sacral nerve passes.

The lung Meridian picture of Shangliao(BL31) Acupoint	Body surface picture of Shangliao(BL31) Acupoint
Anatomy picture of Shangliao(BL31) Acupoint	Section picture of Shangliao(BL31) Acupoint