Orthopedic implant-associated bacterial infections with Staphylococcus aureus constitute a major clinical problem, and large pre-clinical animal models remain scarce. The aim of this study was to establish a standardized method of a localized, acute S. aureus bone infection in the presence of complex implanted devices in a sheep model. Four sheep underwent surgery receiving a complex implanted metallic device with a component stabilizing a bone defect created in the left tibial metaphysis, and an attached component placed in adjacent soft tissue. The bone defect was inoculated with S. aureus strain ATCC25293 (1 × 104 CFU). Twenty one days later, the surgery site was macroscopically evaluated, tissue samples and implants harvested for bacterial cell count quantification and tissue samples histologically analyzed. The animals exhibited clinical signs of localized infection (e.g. swelling, lameness, pain) but did not develop symptoms of sepsis. After euthanasia, macroscopic assessment revealed a localized bone and soft tissue infection at the surgery site. Histologically, an acute inflammation with neutrophils but also signs of bone destruction with necrosis was noted. An ovine model of a localized, acute S. aureus bone infection with complex implants was successfully established and could be used to test novel treatments against orthopedic implant-associated infections.

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羊局部急性植入物相关金黄色葡萄球菌骨感染模型的建立

与骨科植入物相关的金黄色葡萄球菌细菌感染是一个主要的临床问题，大型临床前动物模型仍然稀缺。本研究的目的是在羊模型中存在复杂的植入装置的情况下，建立一种局部急性金黄色葡萄球菌骨感染的标准化方法。四只羊接受了手术，接受了一个复杂的植入金属装置，该装置具有稳定左侧胫骨干骺端骨缺损的组件，以及放置在相邻软组织中的附加组件。用金黄色葡萄球菌菌株 ATCC25293 (1 × 104 CFU) 接种骨缺损。21 天后，对手术部位进行宏观评估，收集组织样本和植入物用于细菌细胞计数定量，并对组织样本进行组织学分析。这些动物表现出局部感染的临床症状(例如肿胀、跛行、疼痛)，但没有出现败血症症状。安乐死后，宏观评估显示手术部位有局部骨和软组织感染。组织学上，注意到有中性粒细胞的急性炎症，但也有骨破坏和坏死的迹象。成功建立了具有复杂植入物的局部急性金黄色葡萄球菌骨感染的绵羊模型，可用于测试针对骨科植入物相关感染的新疗法。注意到中性粒细胞的急性炎症，但也注意到骨破坏和坏死的迹象。成功建立了具有复杂植入物的局部急性金黄色葡萄球菌骨感染的绵羊模型，可用于测试针对骨科植入物相关感染的新疗法。注意到中性粒细胞的急性炎症，但也注意到骨破坏和坏死的迹象。成功建立了具有复杂植入物的局部急性金黄色葡萄球菌骨感染的绵羊模型，可用于测试针对骨科植入物相关感染的新疗法。