Tianshu (ST 25) is a frequently-used acupoint in acupuncture practice. It is reported that deep acupuncture has a better therapeutic effect than routine depth acupuncture. On the basis of reviewing the available literature

the present paper gives a definition about "deep acupuncture" of Tianshu (ST 25) from the anatomy angle

and makes a summary about its safety. This paper also puts forward a set of operation standards for needling Tianshu (ST 25). Moreover

the authors of the present paper also make a systematic analysis on the factors affecting the safety from the punctured depth

the diameter of the acupuncture needle and the operation technique. These methods and standards have an important significance in guiding clinical practice of acu-puncture.