The Clinical Application Value Of ECT And Laboratory Examination On The Diagnosis Of Prosthesis Joint Infection

Background:Artificial joint replacement has become the first choise in the world for the patients who have the severe diease of hip and knee.It can significantly alleviate the patients’ function, can improve the joint activity,and greatly improve the quality of life of the patients. But with the development of artificial joint replacement, its complications are becoming more and more prominent, such as infection, loosening,dislocation and so on.The prosthetic joint infection(PJI) is a devastating complication, not only brings heavy pressure to the patient’s physical,mental and economic,even lead to death, but also hits the doctor’s confidence, and affects the harmony between doctors and patients. The study showed that the infection rate in the first hip and knee replacement is about 1%-2%, increased to 7% in revision arthroplasty. The diagnosis of prosthetic joint infection has no uniform standards.Patients whose symptoms and signs are not obvious often exist misdiagnosis. and timely and effective treatment is always delayed. Laboratory tests, including blood erythrocyte sedimentation rate(ESR) 、 C-reactive protein(CRP)and white blood cell(WBC), are a widely application in clinic, but the sensitivity and specificity are not high, not directly diagnosis infection.Emission computed tomography(ECT) is to detect abnormal bonemetabolismby by radionuclide. In clinical practice it has been widely used in bone tumor, bone fractures and osteomyelitis diagnosis.Recent years,it gradually be used for the diagnosis of prosthetic joint infection, but the value of diagnosis in prosthetic joint infection does not have a particularly large number of reports, especially compared with laboratory,and its advantages and disadvantages need further research.Objective:ECT 、 laboratory examination and the gold standard of infection diagnosis are compared with each other,to study the value of ECT and laboratory examination in prosthetic joint infection, and to provide corresponding basis and relevant recommendations for the application in clinical.Methods:Collecting the database of the patients who sought treatment in our hospital suspected prosthetic joint infection patients between December2013 and December 2015.All patients underwent ECT and laboratory examination(ESR, C- reactive protein, leukocyte and neutrophil ratio).Two of ECT、ESR and C- reaction are positive that can be called combined diagnosis of PJI diagnosis; To analysis the sensitivity and specificity of combined diagnosis,ECT, ESR and C-reactive protein, and to compare them with the "gold standard" by internal consistency analysis of statistics, we can obtain their diagnosis characteristics of prostheticjoint infection, and then determine their application value in the diagnosis of prosthetic joint infection, so that we can obtain the best method for diagnosing prosthetic joint infection.Results:The sensitivity and specificity between ECT and erythrocyte sedimentation rate,C-reactive protein have no statistical difference(P >0.05); Differences in the sensitivity and specificity between ECT combined laboratory tests and erythrocyte sedimentation rate,C-reactive protein(CRP) are significance in statistical(P < 0.05);ECT and combined diagnosis significantly like the gold standard under a consistency check while Kappa>0.4, P < 0.05, good consistency; erythrocyte sedimentation rate and C-reactive protein do not like the gold standard under a consistency check while Kappa<04, P < 0.05, consistency is poor.Conclusion:The negative detection rate of ECT was higher,so it has a high value of exclusion;There is no diffience between single ECT and laboratory examination in sensitivity and specificity;combined diagnosis can significantly improve the sensitivity and specificity of periprosthetic infection; The consistency of ECT and combined diagnosis with the gold standard is higher, so the accuracy is higher.