The effect of pulsing electro magnetic Fields on the Fracture repair

为确定脉冲电磁场加速骨愈合的最佳照射条件，研制便携式动物用脉冲电磁场照射装置。采用兔、狗骨折模型进行研究，得出最佳照射条件为：磁场强度2高斯，脉冲宽度25Musec，频率10 Hz。在此照射条件下，对3只玩具犬骨折骨不连进行了临床试验。骨折通过手术固定，然后在前6周内持续照射，此后每天照射12小时。照射后8~9周临床愈合。临床应用PEMFS治疗23匹赛马新鲜骨折，并与未照射组进行比较。放射学显示有20匹马(87%)与未接受放射治疗的动物相比获得了更早的临床愈合。这些结果表明，PEMFS加速了动物的骨愈合过程，对于治疗骨不连或新鲜骨折非常有效。最后，成功地研制了便携式、无线式的动物PEMFS治疗仪。固定的照射条件和使用简单的电路和小电池(AM3)使小型和轻型(8×5.5×1.5厘米，100克重量)的仪器成为可能。

This study was aimed to establish the optimal irradiation condition for pulsing electromagnetic fields(PEMFs)to accelerate the bone healing process,and to develop the portable PEMFs apparatus for animals.The optimal irradiation conditions of PEMFs obtained in the studies using the fracture models of rabbits and dogs were 2 gauss of magnetic field intensity, 25 musec of pulse width, and 10 Hz of frequency. Clinical trials of PEMFs with this irradiation condition were applied to 3 toy breed dogs with nonunion fractures. The fractures were stabilized surgically, then irradiated continuously during the first 6 weeks and for 12 hours/day thereafter. Clinical unions were obtained after 8 to 9 weeks of irradiation. PEMFs were also applied clinically for treatment of fresh fracture in 23 racing horses, and the results were compared to those without irradiation. Earlier clinical unions demonstrated radiographically were obtained in 20(87%) horses compared to non-irradiated animals. These results suggest that PEMFs accelerate bone healing process in animals and quite effective as the treatment of nonunion or fresh fractures.Finally, the portable and wireless type PEMFs apparatus for animals was successfully developed. Fixation of irradiation condition and a use of simple electric circuit with small batteries(AM3) made a small and light(8 by 5.5 by 1.5 cm and 100g weight) apparatus possible.