针刺足三里深浅效应的研究进展

Research Progress on the Depth-Dependent Effects of Acupuncture at Zusanli (ST36)

摘要: 足三里(ST36)是针灸临床运用最广泛的穴位之一，然其针刺深度在历代文献和现代临床中均存在显著分歧，迄今未形成统一标准。从“浅刺0.5寸”到“深刺2.5寸”均有记载。这一“深浅之争”不仅关系着同一穴位不同操作下临床疗效的差异，更关系到针刺参数标准化等基础问题。近年来，神经科学研究已从神经环路层面证实了足三里深刺与浅刺在激活迷走–胃反射通路上的显著差异，从而将深度问题从经验层面提升至了机制研究层面。文章系统梳理足三里深浅针刺的理论沿革、解剖基础及实验研究进展，剖析深浅效应的本质差异，并提出一个基于解剖层次和超声测量的深度分级标准草案。同时，深入探讨了“得气”与不同神经通路激活的内在联系，并引入一个整合模型以阐释“通路之别”与“量级之别”可能并存的复杂关系。最后，提出了以超声引导下的个体化深度方案，以期为针刺参数的标准化研究和临床决策提供参考。

Abstract: Zusanli (ST36) is one of the most frequently used acupoints in clinical practice. However, the needling depth at this acupoint has long been a subject of considerable controversy in both ancient literature and modern practice, with no unified standard established to date. Recorded depths range from “superficial needling of 0.5 cun” to “deep needling of 2.5 cun.” This debate over needling depth not only concerns the variability of clinical outcomes resulting from different manipulation methods at the same acupoint but also touches upon the fundamental issue of parameter standardization in acupuncture research. In recent years, neuroscientific studies have demonstrated, at the neural circuit level, significant differences between deep and superficial needling at ST36 in activating the vagal-gastric reflex pathway, thereby advancing the depth issue from an empirical proposition to the stage of mechanistic investigation. This article systematically reviews the theoretical evolution, anatomical basis, and experimental research progress concerning superficial versus deep needling at ST36, analyzes the essential nature of depth-dependent effect differences, and proposes a draft grading standard for needling depth based on anatomical layers and ultrasound measurement. Furthermore, it explores the intrinsic relationship between “Deqi” and the activation of distinct neural pathways, and introduces an integrative model to elucidate the potential coexistence and complementarity of “pathway-specific” and “intensity-dependent” effects. Finally, this paper proposes an ultrasound-guided individualized depth strategy, aiming to provide a reference for parameter standardization research and clinical decision-making in acupuncture.