脉冲电磁场对大鼠胫腓骨骨折愈合的影响

The effects of pulsed electromagnetic field on healing of tibia and fibula fractures in rats

目的研究脉冲电磁场对大鼠胫腓骨骨折愈合的影响，并探讨其作用机制。方法选择30只Sprague—Dawley雄性大鼠，建立右侧胫腓骨中段骨折模型后随机分为刺激组与对照组。刺激组大鼠接受频率为15Hz、强度为1．0mT的脉冲电磁场刺激。分别于术后第1，2，3，4，5周末，拍摄X线片评价骨折愈合情况；相同时间点鼠尾静脉取血，采用对硝基苯磷酸盐法检测血清碱性磷酸酶（ALP）活性，酶联免疫吸附分析法检测大鼠骨钙素（BGP）含量，偶氮胂Ⅲ法测定钙离子含量，磷钼酸盐复合物直接分析法测定磷离子含量。于术后第3，5周末行病理学切片检查，观察骨痂组织学变化。结果与对照组相比，刺激组骨折部位骨痂的形成量增加，骨折线消失加快，血清中ALP活性提高（P〈0．05），血清中BGP的含量增加（P〈0．05），骨痂中软骨内化骨和成熟小梁骨提前出现，骨痂中胶原基质的含量增加，骨痂塑形进程加快。结论频率15Hz、强度1．0mT的脉冲电磁场对大鼠胫腓骨骨折愈合有显著的促进作用。

Objective To study the effects of pulsed electromagnetic field （PEMF） in promoting tibia and fibula fracture healing in rats. Methods Thirty rats were divided randomly into two groups after establishing the animal model of artificial tibia and fibula fracture ： a PEMF treated group and a control group. Radiographs were taken immediately postoperatively and once a week thereafter until being sacrificed after week 5. The blood was sampled to measure the activity of alkaline phosphatase （ALP） and the concentration of bone gamma-carboxyglutamic-acid-containing proteins （BGP） , calcium and phosphate in serum once a week, respectively. Histological sections were taken at weeks 3 and 5 to observe the pathological change of bony callus. Results PEMF of 15 Hz and 1.0 mT could significantly increase the amount of bony callus, significantly increase the amount of bony callus, promote the disappearing of fracture lines and the appearance of endochondral ossification and mature bone trabecula. The amount of collagen in bony callus raised and the process of callus moulding accelerated in PEMF treated group. In addition, the activity of ALP（ P 〈 0.04） and the concentration of BGP（ P 〈 0.05） in serum increased. Conclusions The PEMF of 15 Hz and 1.0 mT can obviously promote fracture healing of tibia and fibula in rats.