The effect of electroacupuncture on the healing process of a tibia fracture in a rat model / 全日本鍼灸学会雑誌

ABSTRACT

[Objective]To examine the effect of electroacupuncture on the healing process in a rat model of a tibia fracture. <BR>[Methods]Thirty twelve week old male Wister rats underwent unilateral open osteotomies of the tibiae. Then the rats were assigned randomly to three groupselectroacupuncture group (EA group, n = 10), sham group (n = 10), and control group (n = 10). In the EA group, a cathodal electrode was connected to an acupuncture needle percutaneously penetrating directly at the osteotomy site. An acupuncture needle was inserted 15 mm proximal to the osteotomy site and was used as an anodal electrode. Electroacupuncture was performed daily for 3weeks. Using an electrical stimulator, 5ms square pulses at a frequency of 50 Hz were delivered at 20 μA for 20 minutes. In the sham group, no electrical stimulation was given to the acupuncture needle inserted at the same site as the above described group. In the control group, no treatment was given. The response was determined at one, three, four, and six weeks after osteotomy by radiographic examination. Rats were sacrificed on the sixth week for a macroscopic and mechanical examination. <BR>[Results]The EA groups showed acceleration of the bone healing process compared with the sham and control group (three weeks after osteotomy ;p<0.05 ), and accretion of the callus in the EA group was observed compared with that in the other group at six weeks after (radiographic evaluation;p < 0.05, gross maximum longitudinal dimensions of the callus;p < 0.01, gross maximum transverse dimensions of the callus;p < 0.05). Moreover, biomechanically, there was an excellent result in the EA group compared with the other group at six weeks after osteotomy (p < 0.05). There was no difference between the sham and control group in any evaluation.<BR>[Discussion and Conclusion]Callus formation was promoted in the EA group over the sham and control group. The results of this study indicated that the use of electroacupuncture can enhance callus development and bone mineralization of the bone healing process.