Experimental Study Of The Pulsed Electromagnetic Fields To Promote Healing Of Clavicle Fractures Rabbits

ObjectivePulsed Electromagnetic fields has always been of concern on promoting fracture healing as the deepening of magnetic field on study of the biological effects. The animal model is established to observe the effects of Pulsed Electromagnetic Fields on promot-ing fracture healing by results of CT detection, biomechanical test and bone density measurement. Finally, discusses the mechanism of Pulsed Electromagnetic Fields to promote fracture healing, for providing theory basis about the widely clinical treatment.MethodsMaterials and methods1 Animal treatment1.1 Animal selection and grouping 12 adult white rabbits of Japan are targeted. According to the experiment requires the establishment of model control group, Shangkejiegu bip group and Pulsed Electromagnetic Field treatment group. Rabbits are divided into three groups randomly.1.2 Modeling and treatment To establish a more feasible and more perfect rabbits'bilateral clavicle fracture model. In the sterile operating condition, adult rabbits are taken about 2cm incision in the center of middle clavicle and exposed the clavicle followed by incision, scissors caused bilateral clavicle fracture. Then subclavian stump are fixed by silk after washing powder and sprinkling of penicillin to prevent infections, sutured incision layer by layer and covered the wound with sterile dressing. Each of rabbits continue to be injected GM 3 days after intramuscular. Pulsed Electromagnetic Fields group is treated by therapeutic apparatus. Two poles on the right clavicle Department of rabbits were placed in the wound and the dorsal, daily regular treatment is half an hour. Shangkejiegu chip group is fed rabbits per day 1.2g. Model control group not do other treatment unless pulse two the same size of poles on the right clavicle and the dorsal half an hour a day. All rabbits are killed after four weeks and taken samples of various indicators of bilateral clavicle to test.2. Outcome Measures2.1 CT detection:The original fracture line at both ends of a length are intercept to 5mm of bone segment, then photo to film (tube distance of 120cm, voltage 40kV, exposure time 0.02 seconds). Take the bone cortex thickness measurement in the film thickness. Repeat measurements to three times and take average.2.2 Biomechanical test:The callus specimens are placed on a mechanical testing machine fixture fixed to the torsional stiffness and failure torque test. When the machine other than the loading speed reverse rotation ten min rate of load-induced fracture of specimens, from the load point displacement curve by the computer software automatically calculates the length of the torsional stiffness per centimeter, the damage is caused by fractures of torque. Compare with the healthy side, the experimental impact is reduced by animal collarbone length and thickness differences. 2.3 Bone Density Measurement:The callus specimens are dehydrated in acetone defatted three times of each time 24 hours, then drying, constantting weight, taking dry weight, calculating their size and finding the bone density according to Archimedes law of buoyancy.After the experiment, SPSS16.0 is used to deal with the experimental data. Paired data are compared by the t test and multiple sets of measurement data are compared by the q test.ResultsCT results show that:Pulsed Electromagnetic Fields therapy treatment side is significantly higher than the control side (P <0.01). Bilateral have the same effect in Shangkejiegu bip treatment group (P>0.01), while the treatment groups are significantly higher than the control group. (P<0.01)The biomechanical testing results show that:Pulsed Electromagnetic Fields group is significantly higher than the torsional rigidity of clavicle in the other two groups (P<0.05). Shangkejiegu bip treatment group has control effect with the control group. (P>0.05),The bone mineral density results show that:Compare with Pulsed Electromagnetic Fields, the Shangkejiegu bip treatment group decrease by 3.78%on the density.while the control group decrease by 5.31%on the density. (P<0.01)Conclusion Pulsed Electromagnetic Fields for fracture healing and local osteoporosis have obvious therapeutic effect, compare with the clinical traumatology bone chip commonly used oral medication better effect.