Hand Section, Department of Planned Surgery Z, Gentofte University Hospital, Denmark.
Acta Orthop. 2013 Feb;84(1):92-7. doi: 10.3109/17453674.2013.773121.
There have been numerous reports of animal models of osteomyelitis. Very few of these have been prosthesis models that imitate human conditions. We have developed a new rat model of implant-related osteomyelitis that mimics human osteomyelitis, to investigate the pathology of infection after orthopedic implant surgery.
2 wild-type strains of Staphylococcus aureus, MN8 and UAMS-1, and their corresponding mutants that are unable to produce poly-N-acetyl glucosamine (PNAG) (ica::tet) were injected into the medullary canals of the femur and tibia at 3 different doses: 10(2), 10(3), and > 10(4) CFU/rat. We measured clinical signs, inflammatory markers, radiographic signs, histopathology, and bacteriology in the infected animals.
An inoculum of at least 10(4) cfu of either wild-type bacterial strain resulted in histological, bacteriological, and radiographic signs of osteomyelitis with loosening of the prosthesis. An inoculum of 10(3) CFU gave signs of osteomyelitis but the prosthesis remained in situ. Bacterial inocula of 10(2) cfu gave no signs of osteolysis.
We have established a new knee prosthesis model that is suitable for reliable induction of experimental implant-associated osteomyelitis with the prosthesis in situ, using a small inoculum of S. aureus. At a dose of 10(3) CFU/rat, bacteria unable to produce PNAG (ica::tet) had only minor defects in their virulence.
已有大量关于骨髓炎动物模型的报道。其中，很少有模仿人类情况的假体模型。我们开发了一种新的大鼠假体相关骨髓炎模型，旨在研究骨科植入手术后感染的病理学。
将两种不同的金黄色葡萄球菌（MN8 和 UAMS-1）野生型菌株及其无法产生聚-N-乙酰葡糖胺（PNAG）（ica::tet）的相应突变菌株，以 3 种不同剂量（10（2）、10（3）和> 10（4）CFU/大鼠）注入股骨和胫骨髓腔。我们测量了感染动物的临床症状、炎症标志物、影像学表现、组织病理学和细菌学。
至少 10（4）cfu 的野生型细菌菌株的接种物导致组织学、细菌学和影像学的骨髓炎迹象，假体松动。10（3）CFU 的接种物可引起骨髓炎迹象，但假体仍在原位。10（2）cfu 的细菌接种物未显示骨溶解迹象。
我们建立了一种新的膝关节假体模型，使用小剂量金黄色葡萄球菌（S. aureus）可可靠地诱导原位假体相关骨髓炎。在 10（3）CFU/大鼠的剂量下，无法产生 PNAG（ica::tet）的细菌其毒力仅有轻微缺陷。
