载去甲万古霉素缓释钢板在兔胫骨金葡菌污染模型中病理学与放射学评价

目的探讨载去甲万古霉素缓释钢板在兔胫骨金黄色葡萄球菌污染模型中的预防作用。方法新西兰白兔64只,制备胫骨中段单侧皮质横断骨折模型,分别置入载去甲万古霉素缓释钢板（32只）和普通不锈钢钢板（32只）,注射1×10^5CFU/ml金葡菌,于第1、3、7、14、28天留取病理标本,从病理学和放射学角度比较两种钢板对兔胫骨金葡菌污染模型的预防作用。结果50只兔存活,两组各25只。实验组发生骨髓炎8只,感染率为32%;普通不锈钢钢板对照组发生骨髓炎23只,感染率为92%,两组感染率比较差异有统计学意义（P〈0.05）。两组X线片比较显示：发生感染兔均有骨破坏、骨赘形成、软组织脓肿影等变化,但实验组较对照组发生率低（P〈0.05）。病理学显示,感染兔较未感染兔的软组织及骨HE染色显示：大量中性粒细胞弥漫分布,骨质呈小灶性坏死至片状坏死。结论从病理学和放射学角度观察,载去甲万古霉素缓释钢板在兔胫骨金黄色葡萄球菌污染模型中有较明确的预防作用。

Pathological and radiological evaluation of the infection model of rabbit tibia by staphylococ-cus aureus treated with plate of vancomycin slow releasing

Objective To study the prevention of infection on model of rabbit tibia Staphylococcus aureus by plate of vancomycin slow releasing.Methods 64 White New Zealand rabbits were randomized into 2 groups and unicortical middle tibial osteotomy was performed for each case.32 cases were fixed with vancomycin slow releasing plate and the orther 32 cases were fixed with conventional plate.All cases were inoculated 1×10^5 CFU/ml Staphylococcus aureus directly on to plates.Histological and radiological examinations were performed in 1,3,7,14 and 28 days.Results 50 rabbits survived,with 25 in each group（32%）.The steel plate coating with slow releasing PDLLA-vancomycin got infection in 8 cases（32%）.The control got infection in 23 cases（92%）.The difference was significant（P〈0.05）.Radiology examination showed bone absorption,osteophyte formation and soft tissue abscess（P〈0.05）.Histological examination showed massive neutrophils invasion,focal necrosis.Conclusions The plate of vancomycin has definite prevention effect on the infection model of rabbit tibia Staphylococcus aureus.