超短波及低频脉冲磁疗对骨折愈合中血管内皮生长因子的影响

Effects of ultrashortwave and low frequency pulsed electromagnetic fields on the expression of vascular endothelial growth factor in fracture healing

目的观察超短波及低频脉冲磁疗对骨折愈合过程中血管内皮生长因子（VEGF）表达的影响。方法选用新西兰大白兔56只，随机分为对照组、超短波治疗组（超短波组）、低频脉冲磁疗组（磁疗组）和超短波＋低频脉冲磁疗组（联合组），每组14只。各组分别制备桡骨横断骨折模型。对照组不予干预，其余各组分别给予超短波及低频脉冲磁疗治疗。分别于术后第1，2，4，6周拍摄X线片，评价骨痂以及骨折愈合情况；于术后第1，2，4，6周取材行病理学检查，观察骨折愈合情况，并行免疫组织化学染色检测VEGF蛋白表达水平。结果X线片显示，术后第1、2、4、6周，联合组骨痂生成增多，骨折线模糊，X线评分大于其他组，差异具有统计学意义（P〈0．05）。病理检查结果示，与对照组、超短波组及磁疗组相比，联合组在术后各相应时间点软骨岛生成多，骨痂生成多，重建快，骨折愈合时间短。免疫组织化学染色检测结果示，联合组第1、2、4周的VEGF免疫阳性指数大于对照组、超短波组及磁疗组，差异有统计学意义（P〈0．05）。结论超短波结合低频脉冲磁疗可上调骨折愈合过程中VEGF的表达，从而促进骨痂生长，加快骨折愈合。

Objective To study the effects of uhrashortwave and low frequency pulsed electromagnetic fields on the expression of vascular endothelial growth factor （VEGF） in fracture healing. Methods Fifty-six New Zeal- and rabbits with artificial fractures were randomly divided into 4 groups： a control group, an ultrashortwave group, a low frequency pulsed electromagnetic field group and an ultrashortwave combined with low frequency pulsed electromagnetic field group （combined group） , with 14 in each group. Radiographic evaluation of callus formation and fracture healing, pathohistological examination and detection of VEGF expression through immunohistochemical staining were performed at the 1st, 2nd, 4th and 6th week after the operation. Results Radiographic examination showed that there was significantly greater callus formation in the combined group than in the other groups throughout the healing process. Pathohistologieal examination also revealed significantly more cartilage islets and callus formation in the combined group. At the 1st, 2nd and 4th week after the operation, VEGF positive indexes in the combined group were significantly higher than in the other groups. Conclusion Uhrashortwave combined with low frequency pulsed electromagnetic field exposure can up,regulate the expression of VEGF and thus can accelerate fracture healing.