Objective To compare the difference of bone proportional cun of acupuncture between the description in book Lingshu·Gudu(Miraculous Pivot: Proportional Bone Measurement) and the current National Standard for Locating the Acupoint("National Standard" in short)

so as to determine the proportional relationship of the distance between two positions of the human body in terms of bone proportional cun.Methods A total of 100 volunteers [age: 18-25 years

body weight:(64.0±8.2)kg

and height:(169.3±5.7)cm] were enlisted in the present study.The distances of the bilateral isonym acupoints [Touwei(ST 8)

Yunmen(LU 2)

etc.

] or two sites on the body surface such as the bilateral nipples

Tiantu(CV 22)-umbilicus

etc.

were detected by using a soft ruler or a detector in accordance with the Methods of Anthropometry for Locating Acupuncture Points(GB/T 23237-2009

"National Standard").Results 1) The distances between the bilateral Touwei(ST 8) and bilateral Wangu(GB 12) were(134.54±14.72) mm and(161.73±25.05) mm respectively

both being different to the conventional equal lengths used nowadays.2) The ratios of a) the distance between the bilateral Yunmen(LU 2) and that between the bilateral nipples

and b) the distance between Tiantu(CV 22) and the umbilicus center and that between the umbilicus center and the superior margin of the pubic symphysis were 233.28∶194.46

and 398.09∶153.45

respectively

being identical to the descriptions of book Lingshu·Gudu

but being different to those of the current "National Standard".3) The distances between the anterior axillary fold and the cubital transverse crease

between the posterior axillary fold and the cubital transverse crease

and between Jianyu(LI 15) and the cubital transverse crease were(203.89±32.39) mm

(194.31±64.06) mm

and(286.45±21.16) mm respectively.In terms of proportional bone-length

the distance between the anterior axillary fold and the cubital transverse crease was converted to be 12 cun

being bigger than 9 cun recorded in the "National Standard".4) The distances between the superior border of the pubic symphysis and the superior border of patella

and between the superior border of patella and the patella apex were(439.96±801.51) mm

and(48.41±9.40) mm

separately.When converted to the proportional bone-length

they are identical to the 18.0 cun and 2.0 cun recorded in the current "National Standard".Conclusion The real distances between bilateral Touwei(ST 8) and between two nipples are not equal

the ratio of the distance between Tiantu(CV 22) and the umbilicus center and that between the umbilicus and the superior margin of the pubic symphysis

and the converted proportional bone-length of the distance between the anterior axillary fold and the cubital crease are not identical to the descriptions in current "National Standard" on acupoints location.