[Location] With the lateral wrists towards each other on the palmar aspect and make a loose fist. On the dorsum of the hand, between the 1st and 2nd metacarpal bones, in the middle of the 2nd metacarpal bone on the radial side. Using the transverse crease of the interphalangeal joint of the thumb, place on the margin of the web between the thumb and the index finger of the other hand. The point is where the tip of the thumb touches. (Fig.12)
 
[Regional Anatomy] Skin→subcutaneous tissue→the first dorsal interossei→adductor pollicis. Superficial layer, the distribution of the superficial ramus of the radial nerve, the radial part of the venous network of the dorsum of the hand, and the branches or the subordinatial branches of the artery and vein of the first palmar's back; deep layer, the branches of the deep branches of the ulnar nerve.