A hybrid method to study the mechanical information induced by needle rotating

Abstract

Acupuncture has been used in China for more than 2000 years; its curative effect is acknowledged wildly in the world, but the underlying mechanisms are not revealed. The study focuses on mechanical effect of manual acupuncture. In this paper, a mathematical model based on viscoelastic theory and quasilinear viscoelastic theory of soft tissue is constructed; a hybrid method was used to study the tissue displacement and energy dissipation induced by needle rotation. It shows that (1) needle rotation will induce the extracellular matrix deformation and generate a mechanical stress field in the interstitium, (2) the deformation depends on rotation frequency and is mainly restrained in the vicinity of the needle, and (3) energy dissipation is affected by rotation frequency and very sensitive at low frequency. These results are consistent with experimental observations, and may help to explain some acupuncture theories and phenomena. Furthermore, this work not only contributes to reveal the mechanical effect of acupuncture (needle rotation) by modern scientific methods but also provides a hybrid method to study the strain and stress deriving from mechanical stimuli of connective tissue.