Discussions on the specific c

onvergence patterns of meridians at intersection points are rarely found in classical acupuncture literature. Japanese scholar Kanji Shimizu once preliminarily proposed that the three foot-

yin

meridians do not converge on the same anatomical plane at the Sanyinjiao (SP6); however

the theoretical basis for this view was insufficient. Drawing upon three perspectives

including the natural analogy of the meridian system represented by hydrological models

the structural perspective of physiological organization in traditional Chinese medicine (TCM)

and the transmission patterns of diseases among the six meridians (three

yin

and three

yang

)

the author proposes that the three foot-

yin

meridians intersect at Sanyinjiao (SP6) in a three-dimensional structure: the foot taiyin meridian is the most superficial

followed by foot shaoyin meridian

and foot jueyin meridian lies deepest. In clinical practice

the needling depth at Sanyinjiao (SP6) should be selected rationally based on the target syndrome or disease. For conditions involving multiple meridians

repeated stimulation to obtain

deqi

may be considered.