兔人工膝关节感染模型的构建

Establishment of knee arthroplasty infection model in rabbits

目的：建立兔的人工膝关节感染模型。方法：以长15mm的3mm克氏针作为膝关节内置物,通过兔的股骨髁间窝植入股骨远端。对48只成年新西兰大白兔行上述手术,并随机分为A、B、DC、4组：A组在切口缝合后即刻向关节腔内接种0.5ml1×10^7集落形成单位（Colony forming unit,CFU）的金黄色葡萄球菌ATCC25923,B组接种0.5ml1×10^6CFU的细菌,C组接种0.5ml1×10^5CFU的细菌,D组不接种细菌。于术后分别观察伤口情况,拍摄X线片,细菌培养、组织学变化及C-反应蛋白（C-reactive protein,CRP）和红细胞沉降率（Erythrocyte sedimentation rate,ESR）的变化。结果：术后14d,A组100%（11/11）感染,B组100%（12/12）感染,C组83.3%（10/12）感染,D组无感染;光镜下可见感染内置的克氏针周围炎性细胞较未感染者多;血清CRP和ESR在术后持续保持较高水平。结论：应用该方法术后接种0.5ml1×^金黄色葡萄球菌到膝关节,14d后可以成功建立膝关节置换术（Total knee arthroplasty,TKA）后感染模型。

Objective： design knee prostheses infection modal for rabbits. Methods：The knee implants were designed with 3mm To Kirschner wire for the length of 15mm.Implanted the stem to the distal femoral through intercondylar fossa.forty eight rabbits were divided into 4 groups randomly,12 in each group and finished above-mentioned surgery. Immediately after the surgery,0.5 ml 1×10^7 CFU of Staphylococcus aureus ATCC 25923 was injected into the joints of group A,0.5 ml 1×10^6 CFU in group B and 0.5 ml 1×10^5 CFU in group C, group D were not injected.the animals were sacrificed 2 weeks after injections, wounds were observed and X-ray films were and taken. levels of serum CRP and ESR determined,pathological changes were observed and bacteria cultures were performed. Results： After staphylococcus aureus was injected into the joints right after the surgery.100% knee joint infection in group A and 100%in group B, 83.3% in group C,none knee joint infection in group D. A large amount of inflammatory cells were found in the infected samples, theand levels of serum CRP and ESR were elevated in the infected samples. Conclusion：An animal model of TKA infection can be established successfully at 2 weeks by 0.5 ml 1×10^6 CFU staphylococcus aureus ATCC25923 injecting into the joints immediately after the surgery.