How to find

Locate L5. Inferior to it, the next palpable bony structure is the highest point on the medial sacral crest (sacral spinous processes). Palpate downward for 3 more bony elevations and locate the depression of the 4th sacral foramen less than 1 cun lateral to it. This is on the level of BL-54, located 3 cun lateral to the midline. Located on the same level are BL 34 (Lower Foramen) (over the 4th sacral fora- men) and BL 30 (White Ring Shu) (1.5 cun lateral to the midline).


3 cun lateral to the posterior midline, on the level of the 4th sacral foramen, approximately at the centre of the buttock.


  • Opens the channel and luo vessels, eliminates stagnation
  • Regulates urination
  • Eliminates hemorrhoids


Important local point.