论文部分内容阅读
[目的]构建一种基于钛合金置入物的兔胫骨金黄色葡萄球菌感染模型,并探讨不同菌液浓度在模型制备中的作用。[方法]48只新西兰大白兔随机分成5组,4个实验组每组10只,对照组8只。在胫骨结节内侧钻孔后,向各实验组动物胫骨髓腔内注入浓度分别为1.0×105、1.0×106、1.0×107、1.0×108CFU/ml的ATCC25923金黄色葡萄球菌悬液。然后在髓腔内置入长4.0 cm,直径0.25 cm钛合金棒。对照组注入等量生理盐水后置入相同规格的钛合金棒。术后4周通过肢体外观、体温测量、影像检查、微生物学检测和组织学分析,评价感染模型建立情况,筛选最佳细菌浓度。[结果]术后动物患肢早期局部软组织肿胀,出现跛行,体温呈现2周内明显升高、之后逐渐下降的趋势。术后4周实验组动物放射学显示不同程度骨膜反应,皮质溶解,死骨形成及软组织肿胀等表现。细菌培养结果显示注入的细菌浓度越高,感染越严重,其中C、D组感染率均为100%,高于A、B组;D组死亡率最高。4周组织切片出现骨髓纤维化、坏死骨片等感染表现。[结论]适当浓度的金黄色葡萄球菌菌液髓腔注射联合钛合金棒置入可以构建稳定的兔长骨感染模型,此为骨科金属置入物并发感染的防治研究奠定了基础。
[Objective] To construct a rabbit model of tibia staphylococcus aureus infection based on titanium alloy implant and to explore the role of different bacterial concentrations in model preparation. [Method] 48 New Zealand white rabbits were randomly divided into 5 groups, 10 in each of 4 experimental groups and 8 in control group. After drilling inside of the tibial tubercle, the ATCC25923 Staphylococcus aureus suspension with the concentration of 1.0 × 10 5, 1.0 × 10 6, 1.0 × 10 7 and 1.0 × 10 8 CFU / ml respectively was injected into the tibial medullary cavity of each experimental group. Then insert a 4.0 cm long, 0.25 cm diameter titanium alloy rod into the medullary cavity. The control group was injected with the same amount of normal saline into the same size titanium alloy rod. Four weeks after operation, the establishment of infection model was evaluated by the appearance of limbs, body temperature measurement, imaging examination, microbiological examination and histological analysis, and the best bacterial concentration was screened. [Result] The local soft tissue swelling of limbs in early postoperative limbs appeared limp, the body temperature showed a significant increase within 2 weeks and then gradually decreased. At 4 weeks after operation, the animal radiology in the experimental group showed different degrees of periosteal reaction, cortical lysis, sequestrum formation and soft tissue swelling. Bacterial culture results showed that the higher the concentration of bacteria injected, the more serious the infection. The infection rates of group C and group D were 100%, which were higher than those of group A and B; the mortality of group D was the highest. 4 weeks histological bone marrow fibrosis, necrosis of bone and other infections. [Conclusion] The stable infection model of rabbit long bone can be constructed by injecting the appropriate concentration of Staphylococcus aureus in medullary cavity with titanium alloy rods. This study lays a foundation for the prevention and treatment of concurrent infections of orthopedic metal implants.