中空多孔髋关节假体联合植入式输液港系统在治疗人工关节感染翻修中的意义

The significance of the "hollow porous hip prosthesis combined with implantable infusion port system" in the revision for infected joint arthroplasty

目的 建立兔髋关节置换术后感染模型，探讨中空多孔髋关节假体联合植入式输液港系统在治疗髋关节置换术后感染二期翻修术中的意义。方法 （1） 日本大耳兔 10 只，处死后取右股骨，据此设计出１组为股骨头及柄中空且带孔的假体，１组为股骨头及柄实体的假体。（2） 新西兰白兔 100 只 （10 只为备用），行右侧股骨假体置换术，术毕将含有 1×108 CFU 耐甲氧西林金表皮葡萄球菌的菌液注入右侧髋关节内，术后４周时，兔人工股骨头置换后感染模型建立。（3） 模型建立后清创，实验组 45 只兔植入中空多孔髋关节假体联合植入式输液港系统，分别于术后第１、３周初在输液港中注入万古霉素，其中 22 只于第４周末处死，另外 23 只于第５、７周初再次于输液港中注入万古霉素后，于第８周末处死。对照组 45 只兔植入用 1∶20 的 VCM-PMMA 固定的临时人工股骨头假体系统，其中 22 只于第４周末处死，另外 23 只于第８周末处死。观察两组感染控制率、关节周围软组织病理变化及假体位置。结果 耐甲氧西林表皮葡萄球菌接种后４周所有动物的右侧髋关节均感染。实验组在植入中空假体后第４、８周末的感染数是４只和１只；对照组在植入 VCM-PMMA 临时假体后第４、８周末的感染数是７只和６只。中空多孔髋关节假体联合植入式输液港系统较 VCM-PMMA 临时假体系统在感染控制率方面具有优越性 （χ2＝4.44，P＜0.05）。结论 中空多孔髋关节假体联合植入式输液港系统即可以提高感染控制率，也可以缩短间歇期治疗的时间。

Objective To investigate the effects of “hollow porous hip prosthesis combined with implantable infusion port system” in the two-stage revision for the infection after hip replacement, using the established rabbit model of the infection after hip replacement. Methods （1） The right femurs of 10 Japanese big ear rabbits were harvested after they were sacrificed. And then they were divided into 2 groups： one group with femoral prostheses whose head and handle were hollow and perforated, and the other group with femoral prostheses whose head and handle were noumenal. （2） Prosthesis replacement in the right femur was performed on 100 New Zealand white rabbits （10 standbys）. The bacteria liquid of methicilin-resistant staphylococcus epidermidis （MRSE） of 1×108 colony-forming units （CFU） was infused into the right hip postoperatively. The rabbit model of the infection after femoral arthroplasty was established 4 weeks postoperatively. （3） Debridement was performed after the model was established. 45 rabbits in the experimental group were implanted with the “hollow porous hip prosthesis combined with implantable infusion port system”. Respectively, vancomycin was injected into the infusion port in the 1st and 3rd weeks postoperatively. 22 of the 45 rabbits were sacrificed at the end of the 4th week. Vancomycin was injected into the infusion port for the other 23 rabbits again in the 5th and 7th weeks, and then they were sacrificed at the end of the 8th week. 45 rabbits in the control group were implanted with temporary artificial femoral head prosthesis system fixed with vancomycin-impregnated polymethylmethacrylate （VCM-PMMA） in 1：20. 22 of the 45 rabbits were sacrificed at the end of the 4th week. The other 23 rabbits were sacrificed at the end of the 8th week. The infection control rate, pathologic changes of periarticular soft tissues and prosthesis location of the 2 groups were observed. Results All the right hip joints of animals were infected 4 weeks after MRSE. The number of infected rabbits in the experiment group was 4 and 1 respectively at the end of the 4th and 8th weeks after the implantation of hollow prostheses, and the number of infected rabbits of the control group was 7 and 6 at the end of the 4th and 8th week respectively after the implantation of VCM-PMMA temporary prostheses. The “hollow porous hip prosthesis combined with implantable infusion port system” was superior in the infection rate when compared with the VCM-PMMA temporary prosthesis system （χ2=4.44, P〈0.05）. Conclusions The “hollow porous hip joint prosthesis combined with implanted infusion port system” can improve the infection control rate, and also shorten the treatment time during the intermission.