[Location] Localized in the erect sitting position or prone position. On the back, 1.5 cun lateral to the lower border of the spinous process of the ninth thoracic vertebra. ( Fig.61 )
 
[Regional Anatomy] Skin→subcutaneous tissue→the trapezius→the latissimus dorsi→inferior posterior serratus muscle →the erector spinae. Superficial layer, the distribution of the cutaneous branches of the posterior rami of the ninth and tenth thoracic nerves, and the artery and vein along with them; deep layer, the muscular branch of the posterior rami of the ninth and tenth thoracic nerves and the branches or the subordiantial ramus of the relevant posterior intercostals artery and vein.