Change of Safe Needling Depth at Acupoint GB21 according to Posture and Breathing

Figure 4

Correlation coefficient of needling depth at GB21. The depth to the pleural membrane tends to increase along with body mass index (BMI). However, the variation of depth is very wide even among subjects at the same BMI level. L: depth of the pleural membrane (lung).

(a) BMI versus StP-L

(b) BMI versus PPA-L

(c) BMI versus PPB-L