The current status and future of knee joint revision surgery / 中华骨科杂志

With enhanced recovery after surgery (ERAS), research and application of knee revision protheses and customized components or prostheses in the past decade, revision of total knee arthroplasty (TKA) is developing rapidly. However, periprosthetic joint infection (PJI) has always been a major clinical challenge. A comprehensive preoperative examination to find any potential infection sites should be conducted. The overall condition of the patients should be improved. Surgeons should evaluate the classification and degree of soft tissue and bone defects comprehensively and carefully select appropriate surgical approaches, bone reconstruction strategies, and revision prostheses to ultimately restore the alignment, stability, and the range of motion of the knee joint. In the future, efforts should be made to build a team of experts for the support of revisions of TKAs, including preoperative planning, 3D printing, surgical techniques, and ERAS. Nevertheless, primary TKAs protocols should always be firmly sticked to, which are a key to a low rate of revision surgeries. Prevention of PJIs and periprosthetic fractures, as well as establishing a high-quality follow-up system are of the same importance.

Analysis of the causes of revision total knee arthroplasty / 中华骨科杂志

Objective:To assess causes for revision total knee arthroplasty (TKA) in China using the data of revision TKA in the past 15 years in our single center andcompare the differences in survival time, operation time and blood loss among different revision reasons.Methods:Data of 337 patients (345 knees) with revision TKAs at our institution from January 2007 to December 2021 (15 years) were retrospectively analyzed. The included population consists of 57 males and 288 females. The causes for first revision TKA were identified and compared according to the time of revision surgery as early (up to 2 years) and late revision (more than 2 years). The reason for revision before 2012 and after 2012 was also compared. Furthermore, the differences of survival time, operation time and blood loss among different revision reasons were compared.Results:The most common reasons for revision of knee joints in 345 cases were periprosthetic infection (133 knees, 38.6%), followed by aseptic loosening (97 knees, 28.1%) and joint instability (35 knees, 10.1%). Early revisions were performed in 171 knees (49.6%), while late revisions were performed in 174 knees (50.4%). Periprosthetic infection (96 knees, 56.1%) and aseptic loosening (86 knees, 49.4%) were the most common reasons for early and late revisions, respectively. There were 59 revisions performed before 2012 and 286 revisions performed after 2012, with periprosthetic infection being the main reason for revision in both groups. The percentage of revisions due to infection decreased from 64.4% before 2012 to 33.2% after 2012, and this difference was statistically significant (χ 2=18.790, P<0.001). The proportion of revisions due to aseptic loosening was 15.3% before 2012, which was significantly lower than the proportion of 30.8% after 2012 (χ 2=5.083, P=0.024). The median survival time of the prostheses in the included patients was 30 months, with shorter survival time observed in patients with stiffness, patellar complications, and periprosthetic infection, and longer survival time observed in patients with polyethylene wear and aseptic loosening. There were significant differences in operation time and blood loss among different reasons for revision ( P<0.001). Conclusion:In our specialized arthroplasty center periprosthesis infection was the most common reason for revision. Periprosthesis infection and aseptic loosening needed to be considered for early or late-stage revision. With the development of technique of total knee arthroplasty, the proportion of periprosthesis infection is decreasing, while the incidence of aseptic loosening is increasing.

The impact of constrained prostheses on the outcomes of two-stage revision for periprosthetic joint infection after total knee arthroplasty / 中华骨科杂志

Objective:To assess the clinical efficacy and infection control outcomes of two-stage revision in managing periprosthetic joint infection (PJI) following primary total knee arthroplasty (TKA) utilizing either a low or high constrained prosthesis.Methods:A retrospective analysis was performed on 40 patients who underwent revision TKA in the Sixth People's Hospital Affiliated to Shanghai Jiao Tong University from February 2019 to February 2022. According to the type of prosthesis selected in primary TKA, they were divided into low constrained prosthesis group and high constrained prosthesis group. There were 28 patients (28 knees) in the low constrained group, including 12 males and 16 females, aged 69.0(63.0, 74.0) years, with a body mass index of 25.18±0.55 kg/m 2. And there were 12 patients (12 knees) in the high-constrained group, including 5 males and 7 females, aged 66.5(65.0, 71.5) years, with a body mass index of 23.94±0.51 kg/m 2. All patients underwent two-stage revision surgery, with RHK used in 1 case and LCCK in 27 cases in the low-constrained prosthesis group. In the high-constrained prosthesis group, 3 patients were treated with RHK, 1 patient with PFC Sigma MBT, and 8 patients with LCCK. The preoperative and postoperative range of motion (ROM), Knee Society score (KSS), and postoperative infection control rate were compared between the two groups. Results:All patients were followed up. The follow-up time was 22.79±8.02 months in the low-constrained prosthesis group and 23.92±7.04 months in the high-constrained prosthesis group, with no significant difference between the two groups ( t=0.426, P=0.680). At the last follow-up, the KSS and ROM in the low-constrained prosthesis group were 77.96±9.74 and 93.48°±7.45°, respectively, significantly higher than 38.93±8.01 and 68.89°±9.44° before the operation ( P<0.05). The KSS score and ROM in the high-constrained prosthesis group were 67.83±8.31 and 80.08°±5.89° at the last follow-up, which were also significantly higher than those before operation (34.25±6.31 and 66.50°±10.48°, P<0.05). There was no significant difference in KSS and ROM between the two groups before operation ( P>0.05), but the KSS score and ROM in the low-constrained prosthesis group were significantly higher than those in the high-constrained prosthesis group at the last follow-up ( P<0.05). Bacterial culture results revealed that the primary infectious agents were coagulase-negative Staphylococcus and Staphylococcus aureus, with an overall infection control rate of 80% (32/40). The infection control rate was 89% (25/28) in the low-constrained prosthesis group and 58% (7/12) in the high-constrained prosthesis group, but the difference between the two groups was not statistically significant (χ 2=3.283, P=0.070). Conclusion:Two-stage revision effectively controls PJI, and the clinical outcomes of two-stage revision for PJI after primary TKA with a high-constrained prosthesis are inferior to those with a low-constrained prosthesis. Further exploration is needed to enhance efficacy.

The role of four-generation Oxford nanopore sequencing technology in searching for pathogenic bacteria in periprosthetic infection / 中华骨科杂志

Objective:To explore the application value of Oxford nanopore technologies (ONT) in the diagnosis and treatment of periprosthetic joint infection (PJI).Methods:A prospective analysis was conducted on 32 patients with PJI admitted to the joint department of Xi'an Honghui Hospital from October 2021 to March 2023, who met the 2018 PJI diagnostic criteria of the American Skeletal Infection Society (MSIS), including 15 males and 17 females with an average age of 63.93±8.93 years. 32 revision patients who did not meet the 2018 MSIS PJI criteria during the same period were collected as controls (non PJI group), including 13 males and 19 females with an average age of 65.53±8.54 years. All patients underwent joint fluid puncture before or during surgery, and the specimens were tested by ONT, metagenomic next generation sequencing (mNGS), and general microbial culture. The receiver operating characteristic (ROC) curves were drawn for both groups, and the sensitivity, specificity, positive predictive value, negative predictive value, and Youden index of the three detection techniques were calculated and compared to evaluate the detection efficiency of different detection methods in PJI.Results:Among the 32 patients with PJI, 30 were positive for ONT, with a total of 30 pathogenic bacteria detected, and the detection time was 22.37±8.36 h. 31 were positive for mNGS, with a total of 33 bacterial species detected, and the detection time was 46.25±9.36 h. 17 were positive for microbial culture, with a total of 8 bacterial species detected, and the detection time was 96.23±15.62 h. Among the 32 patients with non PJI group, 1 was positive for ONT and 5 were positive for mNGS, with a total of 1 and 3 bacterial species detected, respectively. The results of microbial culture were all negative. The detection time and area under the curve (AUC) of ONT and mNGS were 22.37±8.36 h and 0.953[95% CI (0.901, 1.006)], 46.25±9.36 h and 0.906[95% CI (0.835, 0.977)], respectively, which were better than those of microbial culture 96.23±15.62 h and 0.766[95% CI (0.678, 0.853)], and the difference was statistically significant ( P<0.05). The sensitivity of ONT, mNGS, and microbial culture were 0.938, 0.969, and 0.531, respectively, and the specificity was 0.969, 0.844, and 1.000, respectively. The Jordan index was 0.906, 0.813, and 0.531, respectively. Conclusion:ONT testing has higher diagnostic efficacy than mNGS and microbial culture in the diagnosis of PJI, and also has advantages in detection time. It also suggests that some PJI are not caused by a single microbial infection.

Analysis of risk factors for periprosthetic joint infection after primary total knee arthroplasty and construction of a nomogram prediction model / 中华创伤骨科杂志

Objective:To investigate the risk factors for periprosthetic joint infection (PJI) after primary total knee arthroplasty (TKA) and construct a nomogram model for prediction of such risks.Methods:In this retrospective study, we enrolled 69 patients with PJI after primary TKA (the infection group, n=69) who had been admitted to Department of Orthopedics, Nanjing Jinling Hospital, The First School of Clinical Medicine, Southern Medical University from January 2010 to December 2019. The non-infection group included the patients of the same kind but without postoperative infection during the same period who were matched according to time of admission, age, and gender in a ratio of 1∶3 ( n=207). The data on body mass index, anesthesia method, operation time, preoperative C-reactive protein, preoperative albumin, and comorbid medical conditions were collected from both groups to screen the risk factors for postoperative development of PJI using univariate and multivariate conditional logistic regression analyses. After a nomogram of the risk factors was plotted using R software, the consistency index (C-index) was calculated. The receiver operating characteristic curve, calibration curve, and clinical decision curve were drawn. Results:Multivariate conditional logistic regression analysis showed that preoperative albumin <35 g/L ( OR=7.166, 95% CI: 3.427 to 14.983, P<0.001), operation time >90 min ( OR=3.163, 95% CI: 1.476 to 6.779, P=0.003), diabetes mellitus ( OR=3.966, 95% CI: 1.833 to 8.578, P<0.001), rheumatic diseases ( OR=3.531, 95% CI: 1.362 to 9.156, P=0.009), and chronic lung diseases ( OR=4.734, 95% CI: 1.790 to 12.521, P=0.002) were risk factors for development of PJI after primary TKA. The nomogram constructed with R software visualized the model. The C-index of the nomogram was 0.809 (95% CI: 0.751 to 0.867), indicating a good predictive capability of the model. The calibration curves of the model showed that the nomogram was in good agreement with the actual observations. The decision curves showed that the threshold probabilities of the model ranged from 0.08 to 0.75, providing a good net clinical benefit. Conclusions:Preoperative low albumin, prolonged operation time, diabetes, rheumatic diseases, and chronic lung diseases may be the risk factors for PJI after primary TKA. The nomogram prediction model based on these factors can provide a reference for clinicians to prevent PJI.

Comparison of Surgical Procedures in the Treatment of Hip Periprosthetic Infection / Comparação entre procedimentos cirúrgicos no tratamento da infecção de prótese do quadril

Abstract Objective The present study aimed to compare the cure rate recovery time and Merle d'Aubigné-Postel functional (MAPF) score after single-stage surgery (C1T) or two-stage surgery (C2T) to treat prosthetic infections of the hip considering sociodemographic and clinical features of the patients. Materials and Methods The present retrospective study occurred in a single center from 2011 to 2014 with 37 studied cases including 26 treated with C1T and 11 with C2T. We compared the cure rate recovery time and MAPF score in the two groups as well as the sociodemographic and clinical features of the patients. We also considered surgical complications and the most common infectious agents. Results The C1T group had a faster functional recovery than the C2T group but there were no significant differences in the cure rate surgical complications or MAPF score. However C1T group patients were significantly younger which may have influenced the outcomes. Staphylococcus spp. was the most common infectious agent (62%). Conclusion Although C2T appears superior regarding infection cure C1T may be preferable for faster functional recovery. However it is critical to consider individual patient characteristics when choosing treatment. Further research with a larger sample size is required to confirm these results.

Resumo Objetivo Comparar a taxa de cura, o tempo de recuperação e a pontuação na escala funcional de Merle d'Aubigné-Postel (EFMA) entre a cirurgia em tempo único (C1T) e a cirurgia em dois tempos (C2T) no tratamento de infecções protéticas do quadril, considerando as características sociodemográficas e clínicas dos pacientes. Materiais e Métodos Foi realizado um estudo retrospectivo num único centro, entre 2011 e 2014, com um total de 37 casos estudados, sendo 26 tratados com C1T e 11 com C2T. Foram comparadas a taxa de cura, o tempo de recuperação e a pontuação EFMA entre os dois grupos, bem como as características sociodemográficas e clínicas dos pacientes. Foram também consideradas as complicações cirúrgicas e o agente infeccioso mais comum. Resultados O grupo C1T teve uma recuperação funcional mais rápida do que o grupo C2T, mas não houve diferenças significativas na taxa de cura, nas complicações cirúrgicas ou na pontuação EFMA. No entanto, o grupo C1T era significativamente mais jovem, o que pode ter influenciado os resultados. Staphylococcus spp. foi o agente infeccioso mais comum (62%). Conclusão Embora a C2T pareça ser superior em termos de cura de infecção, a C1T pode ser preferível para uma recuperação funcional mais rápida. No entanto, as características individuais dos pacientes devem ser consideradas na escolha do tratamento. São necessárias mais pesquisas com um tamanho de amostra maior para confirmar estes resultados.

Epidemiología de las infecciones post osteosíntesis detectadas por baño de ultrasonido en el Servicio de Traumatología del Hospital Universitario de Caracas / Post osteosinthesis infections epidemiology by ultrasound bath in the trauma service of the University Hospital of Caracas

El objetivo de este trabajo es determinar la epidemiología de la infección post osteosíntesis a través de cultivos de fluidos sonicados en los pacientes del Hospital Universitario de Caracas en el período comprendido entre noviembre 2021-noviembre 2022. Se realizó un estudio observacional de tipo, serie de casos, a través de la revisión de historias médicas de todos los casos que acudieron con diagnóstico de infección post osteosíntesis a fin de determinar cuál agente causal fue el más común, factores de riesgo asociados y tratamiento de elección. Se incluyeron 10 pacientes, 70% de sexo masculino y edad promedio de 40,6±17,9 años. Los gérmenes aislados en el cultivo convencional fueron el SAMS, SAMR, Enterobacter cloacae, Staphylococcus coagulasa negativo (10,0% cada uno), el 60,0% de los cultivos en esta modalidad fueron negativos, en el cultivo de fluidos por baño de ultrasonido, el germen más frecuente fue el SAMR en el 30% de los casos, seguido del SAMS con 20%, en menor medida un caso de Staphylococcus coagulasa negativo y una infección polimicrobiana compuesta por K. pneumoniae, E. cloacae y Enterococo sp. El tratamiento médico consistió en antibioticoterapia vía endovenosa, se realizó de acuerdo al antibiograma obtenido del cultivo, el más empleado fue la cefazolina en 30% (en casos de SAMS), seguido de la vancomicina + meropenem y la vancomicina aislada en 20%. Todos los pacientes cumplieron tratamiento al menos por 4 semanas con evolución satisfactoria(AU)

The objective of this work is to determine the epidemiology of post-osteosynthesis infection through sonicated fluid cultures in patients at the Hospital Universitario de Caracas in the period between November 2021 and November 2022. An observational study of type, series of cases, through the review of the medical records of all the cases that presented with a diagnosis of post-osteosynthesis infection in order to determine which causative agent was the most common, associated risk factors and treatment of choice. 10 patients were included, 70% male and mean age 40.6 ± 17.9 years. The germs isolated in the conventional culture were SAMS, SAMR, Enterobacter cloacae, coagulase-negative Staphylococcus (10.0% each), 60.0% of the cultures in this modality were negative, in the culture of fluids by bath of On ultrasound, the most frequent germ was MRSA in 30% of cases, followed by SAMS with 20%, to a lesser extent a case of coagulase-negative Staphylococcus and a polymicrobial infection made up of K. pneumoniae, E. cloacae and Enterococcus sp. The medical treatment consisted of intravenous antibiotic therapy, it was carried out according to the antibiogram obtained from the culture, the most used was cefazolin in 30% (in cases of SAMS), followed by vancomycin + meropenem and vancomycin alone in 20%. All patients complied with treatment for at least 4 weeks with satisfactory evolution(AU)

Microbiological Profi le of Periprosthetic Knee Infections in a Brazilian Unified Health System Hospital Specialized in Highly Complex Orthopedic Surgeries / Perfil microbiológico das infecções periprotéticas do joelho em um hospital do Sistema Único de Saúde especializado em cirurgias ortopédicas de alta complexidade

Abstract Objective We studied the microbiological profile of periprosthetic knee infections treated in a Brazilian tertiary hospital. Methods The study included all patients undergoing revision surgery for total knee arthroplasty (RTKA) between November 2019 and December 2021, with a diagnosis of periprosthetic infection confirmed per the 2018 International Consensus Meeting (ICM) criteria. Results Sixty-two patients had a periprosthetic joint infection (PJI) per the 2018 ICM criteria. Cultures were monomicrobial in 79% and polymicrobial in 21% of cases. The most frequent bacterium in microbiological tissue and synovial fluid cultures was Staphylococcus aureus, observed in 26% of PJI patients. Periprosthetic joint infection with negative cultures occurred in 23% of patients. Conclusion Our results show the following: i) a high prevalence of Staphylococcus as an etiological agent for knee PJI; ii) a high incidence of polymicrobial infections in early infections; iii) the occurrence of PJI with negative cultures in approximately one fourth of the subjects.

Resumo Objetivo Identificar o perfil microbiológico das infecções periprotéticas do joelho tratadas em um hospital terciário brasileiro. Métodos Todos os pacientes submetidos à cirurgia de revisão de artroplastia total do joelho (RATJ), no período compreendido entre novembro de 2019 e dezembro de 2021, e que tiveram o diagnóstico de infecção periprotética confirmado de acordo com critérios do International Consensus Meeting (ICM) 2018, foram incluídos no estudo. Resultados Sessenta e dois pacientes foram diagnosticados com infecção periprotética (IAP) pelos critérios do International Consensus Meeting 2018. Culturas monomicrobianas foram identificadas em 79% e polimicrobianas em 21% dos casos. A bactéria mais frequentemente identificada nas culturas microbiológicas de tecidos e líquido sinovial foi o Staphylococcus aureus, presente em 26% dos pacientes com infecção periprotética. Infecções periprotéticas com culturas negativas ocorreram em 23% dos pacientes. Conclusão Nossos resultados evidenciam: i) alta prevalência de bactérias do gênero Staphylococcus como causadores da IAP do joelho; ii) a alta incidência de infecções polimicrobianas nas infecções precoces e iii) IAP com culturas negativas ocorre em, aproximadamente, um quarto dos pacientes.

Coxiella burnetii in periprosthetic joint infection: a case and systematic review / 中华骨科杂志

One case of periprosthetic infection after artificial joint replacement caused by Coxiella burnetii was reported. The patient was admitted to hospital due to joint pain and sinus formation after artificial knee replacement. Through medical history, physical examination, imaging examination and gene detection, it was confirmed that the infection around the prosthesis was caused by Coxiella burnetii. The patient was treated with two-stage revision surgery combined with sensitive antibiotics. Through literature review, a total of 9 cases of Coxiella burnetii infection after artificial joint replacement were reported, including 6 cases of hip joint and 3 cases of knee joint; 4 cases had clear pathogen exposure history; only one case was found protheses loosening on imaging; 7 cases with positive IgG antibody against Coxiella burnetii; 7 cases were positive for gene detection; 8 cases were negative in etiological examination, and 1 case was not cultured. All patients were treated with doxycycline and hydroxychloroquine. The serological index of 1 case without Q fever symptom turned negative after treatment. 1 case with multiple system organ dysfunction relieved symptoms after treatment, and serological antibody indicators and nuclear medicine results turned negative. All 7 patients were cured after secondary revision surgery. Coxiella burnetii infection after total joint arthroplasty is rare and lacks typical imaging manifestations and clinical features. The diagnosis of Coxiella burnetii infection after total joint arthroplasty mainly depends on gene detection and serological detection. Two-stage revision surgery combined with sufficient and long-term sensitive antibiotics is the main method of treatment.

The diagnostic value of some inflammatory markers for knee joint periprosthetic joint infection / 中华骨科杂志

Objective:To investigate the diagnostic value of erythrocyte sedimentation rate/C-reactive protein (ECR), fibrinogen and D-dimer in periprosthetic infection after artificial knee replacement.Methods:A total of 205 patients, including 62 males and 143 females, aged 66.9±9.5 years (range 26-84 years), who underwent revision of artificial knee joint at Department of Joint Surgery, The First Affiliated Hospital of Xinjiang Medical University from January 2017 to December 2021 were retrospectively collected.122 cases of periprosthetic joint infection (PJI), including 43 cases of acute infection; 79 cases of chronic infection (13 cases of chronic infection combined with rheumatoid arthritis were analyzed separately); there were 83 cases without PJI, including 73 cases of aseptic loosening, 8 cases of prosthesis dislocation and 2 cases of joint stiffness. Erythrocyte sedimentation rate, C-reactive protein, white blood cell count, fibrinogen and D-dimer levels were examined before surgery, and the sensitivity and specificity of the indicators were calculated using the receiver operating characteristic (ROC) curve. The diagnostic value of different inflammatory markers was compared according to the area under curve (AUC).Results:The levels of ECR, erythrocyte sedimentation rate, C-reactive protein, fibrinogen, and D-dimer in acute PJI group were 2.47±2.91, 50 (38, 62) mm/1 h, 31.6 (13.9, 79.3) mg/L, 4.25±0.94 g/L, 763 (453, 1 157) ng/ml, respectively. The chronic PJI group was 3.06±2.95, 50 (34, 64) mm/1 h, 20.4(12.7, 43.3) mg/L, 4.19±0.91 g/L, 586 (317, 1 122) ng/ml, and the non-PJI group was 6.20±4.64, 22 (15, 34) mm/1 h, 4.6 (2.7, 7.74) mg/L, 3.10±0.59 g/L and 363 (181, 591)ng/ml were statistically significant ( P<0.05). The AUC of ECR, erythrocyte sedimentation rate, C-reactive protein, fibrinogen, and D-dimer in the acute PJI group were 0.82, 0.85, 0.90, 0.88, and 0.76, respectively.The optimal critical values were 2.89, 37.00 mm/1 h, 13.6 mg/L, 3.86 g/L, and 443.0 ng/ml, respectively, with sensitivity of 76.7%, 79.1%, 76.7%, 69.8%, and 82.4%, and specificity of 79.5%, 78.3%, 94.0%, 94.0%, 90.4%, and 63.8%, respectively. The AUC of ECR, erythrocyte sedimentation rate, C-reactive protein, fibrinogen, D-dimer, and white blood cell count in the chronic PJI group were 0.77, 0.82, 0.87, 0.85, 0.67, and 0.63, respectively. The optimal critical values are 2.91, 33.00 mm/1 h, 10.9 mg/L, 4.01 g/L, 558.5 ng/ml, and 5.575×10 9 /L, respectively, with sensitivity of 68.2%, 78.8%, 81.8%, 63.6%, 57.9%, and 75.8%, and specificity of 79.5%, 73.5%, 88.0%, 95.2%, 72.5%, and 49.4%, respectively. Conclusion:Fibrinogen has a higher diagnostic value for knee joint PJI, followed by ECR, and D-dimer has the lowest diagnostic value for knee joint PJI.

Gender differences in serological indicators for the diagnosis of chronic periprosthetic infections / 中华骨科杂志

Objective:To investigate the gender differences in serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), platelet (PLT), fibrinogen (FIB) and D-dimer for the diagnosis of chronic periprosthetic joint infection (PJI).Methods:A total of 470 patients who underwent revision arthroplasty in the Department of Joint Surgery, First Affiliated Hospital of Xinjiang Medical University from January 2013 to December 2021 were retrospectively analyzed. According to gender and diagnosis, they were divided into four groups: 78 cases of male chronic PJI, 108 cases of male aseptic loosening, 95 cases of female chronic PJI, and 189 cases of female aseptic loosening. The serological results of CRP, ESR, PLT, FIB and D-dimer were collected before operation. The receiver operating characteristics (ROC) curves were used to determine the optimal cut-off values of CRP, ESR, PLT, FIB and D-dimer for the diagnosis of chronic PJI in different genders, and to calculate their sensitivity and specificity. The diagnostic efficacy of the index was analyzed by comparing the area under curve (AUC) of different indicators.Results:The levels of ESR, PLT and D-dimer in the male chronic PJI group were 43 (20.0, 52.5) mm/1 h, 249×10 9 (204×10 9, 306×10 9) /L, 449 (219,833) μg/L, respectively, which were lower than those in the female group of 56 (40, 65) mm/1 h, 295×10 9 (228×10 9, 364×10 9) /L, and 645 (345, 1 157) μg/L, with statistically significant differences ( Z=-4.17, P<0.001; Z=-2.17, P=0.030; Z=-2.82, P=0.005). The AUC of CRP in the male chronic PJI group was 0.841, which was higher than the AUC of the other four indicators; CRP was combined with ESR, PLT, FIB and D-dimer to establish a joint prediction model for male chronic PJI. The ROC curve showed that the combination of CRP+FIB had a maximum AUC [0.849, 95% CI (0.79, 0.91)], sensitivity of 80% and specificity of 86%. The AUC of CRP in the female chronic PJI group was 0.866, which was higher than the AUC of the other four indices; CRP was combined with ESR, PLT, FIB and D-dimer to establish a combined prediction model for female chronic PJI. The ROC curve showed that the combination of CRP+PLT had the maximum AUC [0.883, 95% CI (0.84, 0.93)], sensitivity of 87% and specificity of 79%. Conclusion:Serologic indicators in patients with chronic PJI are gender-specific. CRP combined with FIB has the highest diagnostic value for the chronic PJI in males, while CRP combined with PLT has the highest diagnostic value for the chronic PJI in females.

Diagnostic value of plasma fibrinogen in chronic periprosthetic infection / 中华骨科杂志

Objective:To investigate the diagnostic value of plasma fibrinogen (FIB) in chronic periprosthetic joint infection (PJI).Methods:A total of 470 patients who underwent revision hip and knee arthroplasty after primary hip and knee arthroplasty in the First Affiliated Hospital of Xinjiang Medical University from January 2013 to December 2021 were retrospectively analyzed. According to the diagnosis of the disease, 173 patients (112 hips and 61 knees) were divided into chronic PJI group, including 78 males and 96 females, aged 65 (53, 72) years; and 297 patients (216 hips and 81 knees) were divided into aseptic loosening group, including 108 males and 189 females, aged 63 (50, 72) years. The preoperative levels of FIB, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), D-dimer and platelet were compared between the two groups, and the sensitivity and specificity of the diagnosis of chronic PJI were calculated. Receiver operating characteristic (ROC) curves were used to determine the optimal cut-off values of FIB, CRP, ESR, platelet and D-dimer for the diagnosis of chronic PJI. The diagnostic efficacy of each indicator was analyzed by comparing the area under curve (AUC) and using a combined diagnostic test.Results:FIB, CRP, ESR, platelets and D-dimer in the chronic PJI group were 4.05 (3.52, 4.72) g/L, 19.5 (10.7, 40.0) mg/L, 50 (28, 60) mm/1 h, 270 (221, 351)×10 9 /L, 514 (261, 873) μg/L, respectively, which were higher than 3.25 (2.80, 3.63) g/L, 3.7 (2.0, 6.7) mg/L, 20 (12, 30) mm/1 h, 225 (182, 269)×10 9 /L, and 310 (167, 569) μg/L in sterile loosening group, with statistically significant differences ( P<0.05). The AUC of FIB, CRP, ESR, platelets and D-dimer in the diagnosis of chronic PJI were 0.78 (95% CI: 0.73, 0.82), 0.86 (95% CI: 0.82, 0.89), 0.80 (95% CI: 0.76, 0.85), 0.68 (95% CI: 0.63, 0.73), 0.64 (95% CI: 0.59, 0.69); the optimal cut-off values were 3.73 g/L, 9.64 mg/L, 39 mm/1 h, 280×10 9 /L, 624 μg/L; the sensitivity was 68%, 79%, 69%, 47%, 43%; the specificity was 81%, 85%, 85%, 81%, 79%, respectively. When CRP, ESR, FIB, platelets and D-dimer were combined sequentially to diagnose patients with chronic PJI, the sensitivity and specificity of the series test were 12.7% and 99.7%, and those of the parallel test were 100% and 37.3%. The combined diagnostic test showed that the maximum AUC of FIB combined with CRP was 0.85 (95% CI: 0.81, 0.89), with a sensitivity of 76% and a specificity of 89%. Conclusion:The clinical value of plasma FIB in the diagnosis of chronic PJI is not superior to that of CRP and ESR, but the combination of FIB and CRP can improve the specificity.

Analysis of risk factors for failure in the treatment of early periprosthetic joint infection by debridement, antibioticsand implant retention combined with intra-articular injection of antibiotics / 中华骨科杂志

Objective:To analyze the risk factors leading to the failure of early periprosthetic joint infection (PJI) treated by debridement, antibiotics and implant retention (DAIR) combined with intra-articular injection of antibiotics.Methods:A total of 100 patients who received DAIR combined with intra-articular injection of antibiotics between January 2010 and October 2020 in the Department of Orthopaedics, First Affiliated Hospital of Xinjiang Medical University, were retrospectively analyzed. There were 47 males and 53 females, with an average age of 62.8±13.0 years (26-84 years). 75 patients were diagnosed as PJI after primary surgery while 25 PJI after revision or debridement, involving 41 hips and 59 knees. According to the clinical outcomes, the patients were divided into the cured group (78 cases) and the uncured group (22 cases). Risk factors were screened by univariate analysis on their gender, age, body mass index, site of infection (hip/knee), synovial white blood cell count, erythrocyte sedimentation rate (ESR), C reactive protein (CRP), time of infection, types of pathogenic bacteria (gram-positive bacteria, gram-negative bacteria or fungi), preoperative sinus tract and previous surgical history. For the factors with P<0.20, multivariate binary logistic regression analysis was performed to determine the independent risk factors. Kaplan-Meier survival curve was drawn and any cause that led to treatment failure was seen as the end point event. Calculate prosthetic survival time and 10-year survival rate. Results:The average follow-up was 59.8±40.6 months (0.3-129.0 months). The infection control rate of DAIR combined with intra-articular injection of antibiotics in the treatment of early PJI was 78% (78/100). The univariate analysis showed that the successful rate of non-fungal infection group (81%, 77/95) was significantly higher than the fungal infection group (20%, 1/5) and the successful rate of the group without previous surgical history (85.3%, 64/75) was significantly higher than that with previous surgical history (56.0%, 14/25, χ 2=7.07, P=0.008; χ 2=9.40, P=0.002). The multivariate binary Logistic regression analysis showed that fungal infection [ OR=0.08, 95% CI(0.01, 0.79), P=0.031] and history of previous surgical intervention [ OR=0.25, 95% CI(0.09, 0.73), P=0.001] were independent risk factors for treatment failure. Kaplan-Meier survival curves showed that the survival time of the prosthesis was 96.83±5.30 months, and the 10-year survival rate was 68.1%. Meanwhile, the survival rate of patients with fungal infection and previous surgical history was significantly lower than that of patients without fungal infection or previous surgical history, the difference was statistically significant (χ 2=15.49, P<0.001; χ 2=8.91, P=0.030). Conclusion:The time of PJI, bacterial virulence and species, and preoperative inflammatory indicators had no effect on the outcome of DAIR combined with intra-articular injection of antibiotics in the treatment of early PJI. However, DAIR was not recommended for patients with a history of surgical intervention and fungal infection.

Significance of serum protein electrophoresis in the diagnosis of Tsukayama IV peri-prosthetic infection / 中华骨科杂志

Objective:To evaluate the value of serum protein electrophoresis in the diagnosis of periprosthetic joint infection (PJI) after hip and knee arthroplasty.Methods:The data of 171 patients who underwent one side hip or knee revision surgery in the affiliated Hospital of Qingdao University from August 2013 to June 2019 were analyzed retrospectively. According to the reasons for revision, 55 patients in PJI group, 29 males and 26 females, aged 67.38±9.60 years, 26 hips and 29 knees, were classified as Tsukayama type IV; Aseptic loosening (AL) group consisted of 116 patients, 67 males and 49 females, aged 69.69±9.20 years, 97 hips and 19 knees .The ratios of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), D-dimer, fibrinogen, serum total protein, serum albumin, serum globulin and serum protein electrophoresis bands in the two groups were statistically analyzed. The sensitivity and specificity of each index were calculated according to the receiver operating characteristic (ROC) curve, and the diagnostic value was compared according to the area under the curve (AUC).Results:There was no significant difference in age, sex or body mass index (BMI) between PJI group and AL group ( P>0.05), but there was significant difference in joint type with 26 hips and 29 knees in PJI group, 97 hips and 19 knees in AL group (χ 2=24.41, P<0.001). The proportion of α1 globulin band was 6.40% (5.30%, 8.10%) in PJI group, which increased significantly compared to 4.20% (3.90%, 4.80%) in AL group ( H=453.50, P<0.001). Albumin band was 49.00% (44.00%, 52.20%) in PJI group, which decreased significantly compared to 54.35% (51.25%, 56.70%) in AL group ( H=4 954.00, P<0.001). The AUC of CRP, ESR, D-dimer, fibrinogen, albumin band and α1 globulin band were 0.87[95% CI (0.80, 0.93)], 0.88[95% CI (0.82, 0.94)], 0.67[95% CI (0.58, 0.76)], 0.87[95% CI (0.82, 0.93)], 0.78[95% CI (0.70, 0.85)] and 0.87[95% CI (0.81, 0.93)], respectively. Conclusion:Albumin bands and α1 globulin bands in serum protein electrophoresis had high diagnostic value for PJI, and the accuracy of α1 globulin bands was as good as that of routine inflammatory markers such as CRP and ESR.

Infecciones osteoarticulares: epidemiología, etiología y evolución clínica en un centro de referencia nacional / Osteoarticular infections: epidemiology, etiology and clinical evolution in a national reference center / Infecções osteoarticulares: epidemiologia, etiologia e evolução clínica em um centro de referência nacional

Introducción: la infección osteo-articular es una patología compleja, y su prevalencia esta en aumento. Conocer las principales características de su presentación clínica, etiología y evolución permite mejorar su abordaje. Material y métodos: estudio observacional, retrospectivo, período 01 de enero 2020 a 31 diciembre 2020 en el Instituto Nacional de Ortopedia y Traumatología. Se incluyeron todos los pacientes adultos ingresados con diagnóstico clínico de infección osteo-articular y que fueron asistido en conjunto por Enfermedades Infecciosas y Traumatología en el período de estudio. Todos los casos contaban con uno o más cultivos microbiológicos profundos. Resultados: hubo 132 pacientes con infección osteo-articular, la relación hombre-mujer fue 2 a 1 y una media de 53 años. La presentación clínica fue con dolor, fístula y signos fluxivos locales. Las infecciones más frecuentes fueron de fracturas y prótesis articulares. El 54% de las infecciones fue por cocos gram positivos, 31% por enterobacterias y 13% bacilos gram negativos no fermentadores. En cuanto al perfil de sensibilidad 33% de los cocos fueron meticilino resistentes y 43% de las enterobacterias multirresistentes. Conclusión: La patología mas frecuente en 2 de cada 3 ingresos fue la infección de fracturas y la asociada a material implantado. A la complejidad habitual del tratamiento quirúrgico y antimicrobiano de esta patología se suma que 3 de cada 10 microorganismos aislados fueron resistentes.

Introduction: osteoarticular infections are a complex condition that are gradually increasing in prevalence. Learning about its clinical presentation, etiology and evolution will enable improving its management. Method: observational, retrospective study of cases seen at the National Orthopedic and Traumatology Institute from January 1st, 2020 to December 31st, 2020. All adult patients admitted with clinical diagnosis of osteoarticular infection who were assisted jointly by the Infectious Diseases and Traumatology units in the above mentioned period were included in the study. All cases had at least one deep microbiological cultures. Results: there were 132 patients with osteoarticular infection, female to male ratio was 2-to-1 and average age was 53 years old. Clinical presentation was characterized by pain, fistula and local fluxiye signs. The most frequent infections were fracture and prosthetic joint infections. Fifty four percent of infections were caused by gram-positive coccus, 31% were caused by enterobacteria and 13% by nonfermenting gram-negative bacilli (NFGNB). As to the sensitivity profile, 33% of cocci were methicillin-resistant and 43% of enterobacteria were multidrug-resistant. Conclusions: the most frequent pathology in 2 out of three hospitalizations were fracture infection and infections in orthopedic-related devices. The usual complexity.

Introdução: a infecção osteoarticular é uma patologia complexa, e sua prevalência está aumentando. Conhecer as principais características da sua apresentação clínica, etiologia e evolução permite-nos melhorar a sua abordagem. Material e métodos: estudo observacional, retrospectivo, que inclui pacientes atendidos no período 1º de janeiro -a 31 de dezembro de 2020 no Instituto Nacional de Ortopedia e Traumatologia. Foram incluídos todos os pacientes adultos internados com diagnóstico clínico de infecção osteoarticular atendidos conjuntamente por especialistas em Infecciologia e Traumatologia. Em todos os casos foram realizadas uma ou mais culturas microbiológicas profundas. Resultados: foram incluídos 132 pacientes diagnosticados com infecção osteoarticular, a relação homem-mulher foi de 2 para 1 e a idade média foi 53 anos. A apresentação clínica foi: dor, fístula e sinais inflamatórios agudos locais. As infecções mais frequentes foram as associadas a fraturas e próteses articulares. 54% das infecções foram devidas a cocos Gram positivos, 31% a enterobactérias e 13% a bacilos Gram negativos não fermentadores. Em relação ao perfil de sensibilidade, 33% dos cocos eram resistentes à meticilina e 43% das enterobactérias eram multirresistentes. Conclusão: a patologia mais frequente em 2 dos 3 internamentos foi a infecção das fracturas e estava associada ao material implantado. Acrescenta-se à complexidade usual do tratamento cirúrgico e antimicrobiano desta doença o fato de que 3 em cada 10 microrganismos isolados eram resistentes.

Endocarditis infecciosa luego del implante de válvula aórtica por cateterismo / Infective Endocarditis after Transcatheter Aortic Valve Implantation

RESUMEN Introducción: La endocarditis infecciosa (EI) post implante percutáneo de válvula aórtica (TAVI) es poco frecuente, con una alta tasa de morbimortalidad. Métodos: Se analizaron 630 pacientes consecutivos con TAVI, de los cuales 6 (0,95%) presentaron EI. Resultados: Cuatro eran hombres, edad 81,3 ± 2,2 años, y todos sintomáticos. La fracción de eyección ventricular izquierda (FEVI) fue 56,8 ± 5,3%. Todos recibieron un implante exitoso y uno presentó regurgitación moderada. Dos requirieron marcapaso definitivo, a uno de ellos se le debió recolocar el cable a las 24 hs. La EI se presentó a los 63,5 ± 73,3 días (mediana de 35 días). El germen aislado fue un coco (+) en cuatro casos. En uno se observó una vegetación en el ecocardiograma transesofágico. Un paciente falleció dentro de los 30 días. El seguimiento fue a 23 ± 22 meses, ningún paciente presentó nuevos eventos o internaciones. En el eco Doppler la FEVI fue de 55,9 ± 4,6%, el gradiente medio 8,2 ± 1,8 mmHg y la velocidad pico de 1,8 ± 0,2 m/seg. Un paciente terminó una regurgitación moderada. Conclusiones: En esta serie de pacientes, la EI post TAVI fue poco frecuente y presentó una evolución favorable con el tratamiento antibiótico.

ABSTRACT Background: Infective endocarditis (IE) after transcatheter aortic valve implantation (TAVI) is a rare complication with high morbidity and mortality. Methods: Of 630 consecutive patients undergoing TAVI, 6 (0.95%) presented IE. Results: Four patients were men, mean age was 81.3 ± 2.2 years and all the patients were symptomatic. Left ventricular ejection fraction (LVEF) was 56.8 ± 5.3%. The procedure was successful in all the patients and one presented moderate regurgitation. Two patients required definitive pacemaker and the lead had to be reimplanted 24 hours later in 1 patient. Time to IE was 63.5 ± 73.3 days (median 35 days). A Gram-positive coccus was isolated in four cases. One patient presented a vegetation on transesophagic echocardiography. One patient died within 30 days. During follow-up of 23 ± 22 months none of the patients presented new events or hospitalizations. On Doppler echocardiography, LVEF was 55.9 ± 4.6%, mean trans-aortic gradient was 8.2 ± 1.8 mm Hg and peak systolic velocity was 1.8 ± 0.2 m/s. One patient had moderate regurgitation. Conclusions: In this series of patients, IE after TAVI was uncommon and had a favorable course with antibiotic treatment.

Mixed bacterial-fungal infection following total hip arthroplasty: A case report / 中华创伤杂志(英文版)

Prosthetic infection is one of the severe postoperative complications of arthroplasty. Mixed bacterial-fungal prosthetic infection is rare but can be disastrous. This case was a 76-year-old female suffered from prosthetic infection following total hip replacement due to femoral neck fracture and underwent multiple debridements. The culture of periprosthetic tissue was bacteriologically sterile following the first debridement, while the Staphylococcus hominis was identified in the second debridement in the previous hospitalization where fungal infection had not been considered. Thus the pathogen spectrum of anti-infection therapy failed to contain fungus. Ultimately, the culture result of our sampled periprosthetic tissue during the third debridement was Candida albicans without bacterium in our hospital. The fungal prosthetic infection was successfully treated by a two-stage revision with antifungal drugs. Accurate diagnosis and standardized treatment is the key to the therapy of infection after hip arthroplasty, especially for mixed bacterial-fungal prosthetic infection.

Debridement, antibiotics irrigation and implant retention for acute periprosthetic joint infection after primary total joint arthroplasty / 中华创伤骨科杂志

Objective:To analyze the clinical efficacy of debridement, antibiotics irrigation and implant retention (DAIR) in the treatment of acute periprosthetic infection (PJI) and to explore the risk factors leading to the failure of DAIR.Methods:From January 2010 to January 2021, 122 patients underwent DAIR for acute PJI at Department of Orthopedics, General Hospital of Eastern Theater of PLA. They were 55 males and 67 females, aged from 50 to 86 years (mean, 68.0 years). Their C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), body temperature, white blood cell count and visual analogue scale (VAS) were compared at admission and discharge to analyze the clinical efficacy of DAIR. The 122 patients were assigned into a cured group (81 cases) and an uncured group (41 cases). Risk factors were screened by univariate analysis out of their gender, age, body mass index, site of infection, type of infection (early postoperative infection or acute hematogenous infection), type of surgery (primary or revision), comorbidities, CRP, ESR, albumin and hemoglobin at admission, duration of symptoms, Staphylococcus aureus infection, multiple bacterial mixed infection, and preoperative sinus tract. For the factors of P<0.05, multivariate binary logistic regression analysis was used to determine the risk factors for failure of DAIR. Survival curves were plotted for the patients using DAIR failure as the endpoint event. Results:The CRP, ESR, VAS score, body temperature and white blood cell count at discharge in the 122 patients were significantly lower than the corresponding values at admission ( P<0.05). The success rate of DAIR was 66.39%(81/122). The multivariate binary logistic regression analysis suggested that duration of symptoms over 3 weeks( OR=1.230, 95% CI: 1.092~1.576, P=0.020), Staphylococcus aureus infection( OR=4.607, 95% CI: 2.057~10.318, P<0.001), preoperative sinus tract( OR=6.115, 95% CI: 2.630~14.220, P<0.001) and multiple bacterial mixed infection( OR=2.600, 95% CI: 1.131~5.977, P=0.020) were risk factors for DAIR failure; Kaplan-Meier survival curve also confirmed that the patients with Staphylococcus infection, multiple bacterial mixed infection, duration of symptoms over 3 weeks, or preoperative sinus tract had a significantly lower rate of survival than their controls ( P<0.05). Conclusions:For acute PJI, DAIR can be used to retain the prosthesis and control infection. However, DAIR is not recommended for the patients with Staphylococcus aureus infection, multiple bacterial mixed infection, symptoms lasting more than 3 weeks, or preoperative sinus formation.

Changing of white blood cell count and proportion of polymorphonuclear cells of synovial fluid in total knee arthroplasty patients before and after operation / 中华骨科杂志

Objective:To investigate the changes and clinical significance of white blood cell (WBC) count and polymorphonuclear cells (PMN) proportion of synovial fluid after primary total knee arthroplasty (TKA).Methods:A total of 59 patients (92 knees) who underwent TKA from April 2021 to July 2021 were included, including 13 males (20 knees) and 46 females (72 knees). The patients were with average age 65.17±7.49 years old (range 48-79) and with body mass index (BMI) 27.64±3.74 kg/m 2 (range 17-36 kg/m 2). There were 26 cases involved lateral knee and 33 cases bilateral knees. The left knee was involved in 46 knees, while other 46 were involved in right side. There were 54 patients diagnosed as osteoarthritis (84 knees) and 5 as rheumatoid arthritis (8 knees). None of the patients received antibiotics after hospitalization. Antibiotics were used prophylactically 30 min before surgery and after surgery. The synovial fluid WBC count and PMN proportion were detected during operation (It reflects the normal preoperative level) and on the 2nd, 5th and 35th day after operation. The changes of these indexes were analyzed. The unmixed synovial fluid was collected after the incision of the joint capsule during the operation. The outer upper edge of the patella was taken as the puncture point to extract the synovial fluid on the 2nd, 5th and 35th days after the operation. The final follow-up end point was a diagnosis of acute periprothetic joint infection (PJI) or 90 days of follow-up for patients without PJI. Results:After operation, the synovial fluid WBC count and PMN proportion showed a trend of increasing and then decreasing. The synovial fluid WBC count were 0.222(0.100, 0.567)×10 9/L, 20.011(14.573, 29.129)×10 9/L, 6.080(3.676, 8.797)×10 9/L, 0.533(0.394, 0.749)×10 9/L before surgery and at 2nd, 5th and 35th day after surgery respectively. The difference before and after operation was statistically significant (χ 2=247.343, P<0.001). The synovial fluid PMN proportion were 19.9%(15.0%, 30.0%), 96.0%(95.0%, 97.0%), 91.0%(89.0%, 93.0%) and 20.5%(15.6%, 26.9%) respectively and with significant difference (χ 2=242.521, P<0.001). Pairwise comparison of synovial fluid WBC count and PMN proportion before and on day 35 indicated no statistical significance ( P>0.05). However, the differences compared with that at other time points were statistically significant ( P<0.05). Conclusion:The synovial fluid WBC count and PMN proportion increased rapidly in the short term after TKA and then decreased to the preoperative level at varied rates. Referring to the Musculoskeletal Infection Society (MSIS) recommended threshold for diagnosing infection during the acute stress period (within 5 d postoperatively) can result in false positives. Recovery to preoperative levels at 35th days postoperatively can be used as a basis for ruling out early infection. Thus, early joint fluid PMN proportion may have more diagnostic value than WBC counts.

Values of combined detection of indexes related to serum inflammation and platelet in diagnosis of chronic periprosthetic joint infection / 中华创伤骨科杂志

Objective:To investigate the values of combined detection of serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), platelet count (PC), platelet count/mean platelet volume (PC/MPV) and platelet plateletcrit (PCT) in the diagnosis of chronic periprosthetic joint infection (PJI).Methods:From January 2013 to December 2019, 441 patients underwent hip or knee joint revision at Department of Articular Surgery, The First Hospital Affiliated to Xinjiang Medical University. The patients were divided into a chronic PJI group and an aseptic prosthetic loosening group. In the chronic PJI group of 147 cases (86 hip ones and 61 knee ones), there were 64 males and 83 females, with a mean age of 66 (54, 72) years. In the aseptic prosthetic loosening group of 294 cases (210 hip ones and 84 knee ones), there were 98 males and 196 females, with a mean age of 63 (49, 72) years. The preoperative levels of CRP, ESR, PC, PC/MPV and PCT were compared between the 2 groups. The best cut-off value, sensitivity and specificity of the above indicators for the diagnosis of chronic PJI were recorded. The diagnostic efficacy of the 5 indicators in combination for chronic PJI was evaluated by comparing the area under the curve (AUC) among the indicators and analyzing the results of combined diagnostic detections.Results:Except for gender and joint revision site, there was no significant difference in the other general data between the 2 groups, showing comparability ( P>0.05). The levels of CRP, ESR, PC, PC/MPV and PCT in the PJI group were significantly higher than those in the aseptic prosthetic loosening group ( P<0.05). For CRP, ESR, PC, PC/MPV and PCT, respectively, the best cut-off values were 9.05 mg/L, 38.5 mm/h, 288×10 9/L, 29.34 and 0.33%, the sensitivities 83%, 71%, 44%, 44% and 33%, the specificities 85%, 86%, 84%, 84% and 90%, and the AUCs 0.868, 0.822, 0.688, 0.696 and 0.659. For CRP+ESR+PC+PC/MPV+PCT and CRP+PC+PC/MPV+PCT, respectively, the AUCs were 0.871 and 0.882, the sensitivities 80% and 84%, and the specificities 86% and 84%, showing significant differences in the diagnosis of chronic PJI compared with ESR, PC, PC/MPV and PCT alone ( P<0.05). Conclusion:In the diagnosis of chronic PJI, serum CRP and ESR combined with PC, PC/MPV and PCT have a reference value, but PC, PC/MPV or PCT alone only has a limited value.