Short-course antibiotics for prosthetic joint infections treated with prosthesis retention

The purpose of the present study was to evaluate the significance of shortening the antibiotic treatment duration in prosthetic joint infections (PJI) treated with debridement, antibiotics and implant retention (DAIR). In April 2006 we shortened the total antibiotic treatment duration in total knee arthroplasty (TKA) PJIs from 6 months to 3 months and in total hip arthroplasty (THA) PJIs from 3 months to 2 months. All patients with TKA or THA PJI treated with DAIR between February 2001 and August 2009 were reviewed retrospectively. There were 132 patients treated with DAIR, of whom 86 (65%) completed the antibiotic therapy and were therefore eligible for comparison concerning the length of antibiotic treatment. There were 32 (37%) THA and 54 (63%) TKA PJIs in the comparison. The treatment succeeded in 34 (89.5%) patients treated with longer antibiotic treatment and in 42 (87.5%) of those treated with shorter antibiotic treatment (p 0.78). Our conclusion is that if the patient completes the antibiotic therapy, treatment duration of 3 months in TKA PJIs and 2 months in THA PJIs is as good as longer antibiotic treatment of 6 months or 3 months, respectively, in patients treated with DAIR.     

Meta-Analysis of Sonication Fluid Samples from Prosthetic Components for Diagnosis of Infection after Total Joint Arthroplasty

This meta-analysis included 12 studies that evaluated sonication fluid cultures (SFC) for the diagnosis of prosthetic joint infection (PJI). The pooled sensitivity and specificity were 0.80 (95% confidence interval [CI], 0.74 to 0.84) and 0.95 (CI, 0.90 to 0.98), respectively. Subgroup analyses showed that a 14-day anaerobic culture may improve sensitivity, the use of centrifugation or vortexing may improve specificity, and the use of 400 to 500 ml of Ringer''s solution for containers may improve sensitivity and specificity. The best SFC cutoff was ≥5 CFU. In conclusion, SFC has high sensitivity and very high specificity for diagnosing PJI.     

The application of sonication in diagnosis of periprosthetic joint infection

Periprosthetic joint infection (PJI) is a catastrophic complication after total joint arthroplasty. It has always been difficult to diagnose PJI, which is characterised by existence of biofilm around the implants. The application of sonication has proven advantageous for pathogen detection. This meta-analysis of clinical trials was performed to evaluate the diagnostic value of sonication and to compare it with traditional bacterial culture. We assessed 16 studies that evaluated sonication fluid cultures (SFC) for the diagnosis of PJI. It was shown that sonication may be of great value in PJI diagnosis, with a pooled sensitivity of 0.79 (95 % confidence interval [CI]?=?0.76–0.81), specificity of 0.95 (CI?=?0.94–0.96), DOR of 71.20 (CI?=?31.08–163.10), PLR of 15.25 (CI?=?6.44–36.15), and NLR of 0.23 (CI?=?0.18–0.30). The AUC value of the SROC was 0.90. The results of this meta-analysis showed that culture of fluid after sonication was of great value for PJI diagnosis. Sonication was more sensitive than traditional tissue culture with lower specificity, especially for patients previously taking antibiotics.     

Polysaccharide intercellular adhesin or protein factors in biofilm accumulation of Staphylococcus epidermidis and Staphylococcus aureus isolated from prosthetic hip and knee joint infections

Nosocomial staphylococcal foreign-body infections related to biofilm formation are a serious threat, demanding new therapeutic and preventive strategies. As the use of biofilm-associated factors as vaccines is critically restricted by their prevalence in natural staphylococcal populations we studied the distribution of genes involved in biofilm formation, the biofilm phenotype and production of polysaccharide intercellular adhesin (PIA) in clonally independent Staphylococcus aureus and Staphylococcus epidermidis strains isolated from prosthetic joint infections after total hip or total knee arthroplasty. Biofilm formation was detected in all S. aureus and 69.2% of S. epidermidis strains. Importantly, 27% of biofilm-positive S. epidermidis produced PIA-independent biofilms, in part mediated by the accumulation associated protein (Aap). Protein-dependent biofilms were exclusively found in S. epidermidis strains from total hip arthroplasty (THA). In S. aureus PIA and proteins act cooperatively in biofilm formation regardless of the infection site. PIA and protein factors like Aap are of differential importance for the pathogenesis of S. epidermidis in prosthetic joint infections (PJI) after THA and total knee arthroplasty (TKA), implicating that icaADBC cannot serve as a general virulence marker in this species. In S. aureus biofilm formation proteins are of overall importance and future work should focus on the identification of functionally active molecules.     

Unicompartmental knee arthroplasty is associated with lower proportions of surgical site infection compared with total knee arthroplasty: A retrospective nationwide database study

BackgroundThis study aimed to clarify the association between types of knee arthroplasty (KA) (total knee arthroplasty (TKA) or unicompatmental knee arthroplasty (UKA)) and surgical site infection (SSI) with adjustment for various factors, using a Japanese national database.MethodsData on 181,608 patients who underwent unilateral primary KA for osteoarthritis from 2010 to 2017 were obtained from the Japanese Diagnosis Procedure Combination database. SSI was identified based on International Classification of Diseases 10th Revision codes. Deep SSI (i.e. periprosthetic joint infection (PJI)) was identified as SSI treated with surgical procedures. Multivariable logistic regression analyses for SSI and PJI were performed, in which dependent variables included types of KA, patient backgrounds (sex, age, body mass index (BMI), smoking status, comorbidities), and seasonality.ResultsEight percent of analyzed patients underwent UKA, while 92% underwent TKA. The proportions of SSI and PJI after UKA were 0.9% and 0.3%, respectively, both of which were lower than those after TKA (1.9% and 0.6%) (P < 0.001). Multivariable analyses showed lower proportions of SSI for UKA (adjusted odds ratio, 0.47; 95% confidence interval, 0.37–0.60; P < 0.001) and PJI (adjusted odds ratio, 0.47; 95% confidence interval, 0.34–0.65; P < 0.001) than TKA. Other factors associated with both SSI and PJI included male sex, BMI >30 kg/m², renal dysfunction and summer season.ConclusionUKA was associated with lower proportions of SSI and PJI than TKA. Surgeons should carefully consider the indication of UKA before performing TKA, especially in patients with knee unicompartmental osteoarthritis who are at a high risk for SSI or PJI.     

Custom intramedullary intercalating device for treatment of supracondylar fracture between constrained total knee arthroplasty and well-fixed total hip arthroplasty

Management of periprosthetic fractures between ipsilateral total knee arthroplasty (TKA) and total hip arthroplasty (THA) is difficult, and is further complicated in the setting of poor femoral bone stock. We present a case of supracondylar fracture between THA and long-stemmed TKA femoral components in a patient with rheumatoid arthritis, deficient metaphyseal bone stock, and recurrent fractures. A long custom intramedullary intercalating component was devised to link the well-fixed existing THA stem to a revision distal femoral component. The resulting construct was stable and allowed for full weight-bearing ambulation, representing a useful treatment option in the management of periprosthetic fractures between revision TKA and well-fixed THA.     

Diagnosis of knee prosthetic joint infection; aspiration and biopsy

BackgroundProsthetic joint infection (PJI) is a significant cause of morbidity and mortality following knee replacement surgery. The diagnosis can be challenging and is based on a combination of clinical suspicion, radiographic findings and also biochemical/ microbiological investigations. Our Aim was to review the role of aspiration and biopsy in the diagnosis of PJI in Total Knee Arthroplasty (TKA).Method/resultsAspirated synovial fluid should be analysed by direct culture, via blood culture bottles, EDTA bottles for cell count and ‘point of care’ testing such as leucocyte esterase or alpha defensin. Synovial WCC and PMN cell percentage are important steps in diagnosis of both acute and chronic PJI. A minimum of 5 deep samples using a 5 clean instrument technique should be obtained and sent for tissue culture done either blind or arthroscopic. Formal fluoroscopic guided interface biopsy has also been described with excellent results. In a recent series of 86 TKRs preoperative arthroscopic biopsy group had a sensitivity of 100%, specificity of 94.7%, positive predictive value of 87.4% and a negative predictive value of 100%.ConclusionIn the presence of clinical suspicion with raised biomarkers, it is recommended that aspiration +/- biopsy with synovial fluid testing is performed. Direct culture and cell count are recommended. ‘Point of care tests’ such as Leucocyte Esterase testing should be considered. Duration of culture, including pathogen and host factors, should be discussed with a local microbiology/ID department in the context of a formal multi-disciplinary team.     

人工关节置换术后隐性失血对下肢深静脉血栓形成的影响

目的探讨人工髋、膝关节置换术（Total hip arthroplasty，THA；Total knee arthroplasty，TKA）围手术期失血情况对术后下肢深静脉血栓形成（deep vein thrombosis，DVT）的临床影响。方法92例THA、TKA术后DVT发生情况进行分析。THA为51例（56髋），TKA为41例（49膝）。术后7～10d采用彩色多普勒检查双下肢DVT的发生。对临床失血的相关指标与人工关节置换术后DVT的改变进行了分析。结果术后发生DVT患者共计28例，发生率为30．43％（28／92）。发生DVT的患者临床实际失血总量、隐性失血总量、术后失血总量、术后隐性失血量平均值分别为1648．53ml、844．35ml、1016．17ml、735．87ml，与未发生DVT的患者四项指标比较差异有统计学意义（P〈0．05）。结论隐性失血量的增加提高了术后DVT形成的风险。对隐性失血量变化的认识和发生机制的研究有助于人工关节置换术后下肢DVT的防治。     

Development and validation of baseline,perioperative and at-discharge predictive models for postsurgical prosthetic joint infection

Objectives

To develop and validate baseline, perioperative and at-discharge risk-scoring systems for postsurgical prosthetic joint infection (PJI) in patients undergoing arthroplasty.

Rapid Molecular Microbiologic Diagnosis of Prosthetic Joint Infection

We previously showed that culture of samples obtained by prosthesis vortexing and sonication was more sensitive than tissue culture for prosthetic joint infection (PJI) diagnosis. Despite improved sensitivity, culture-negative cases remained; furthermore, culture has a long turnaround time. We designed a genus-/group-specific rapid PCR assay panel targeting PJI bacteria and applied it to samples obtained by vortexing and sonicating explanted hip and knee prostheses, and we compared the results to those with sonicate fluid and periprosthetic tissue culture obtained at revision or resection arthroplasty. We studied 434 subjects with knee (n = 272) or hip (n = 162) prostheses; using a standardized definition, 144 had PJI. Sensitivities of tissue culture, of sonicate fluid culture, and of PCR were 70.1, 72.9, and 77.1%, respectively. Specificities were 97.9, 98.3, and 97.9%, respectively. Sonicate fluid PCR was more sensitive than tissue culture (P = 0.04). PCR of prosthesis sonication samples is more sensitive than tissue culture for the microbiologic diagnosis of prosthetic hip and knee infection and provides same-day PJI diagnosis with definition of microbiology. The high assay specificity suggests that typical PJI bacteria may not cause aseptic implant failure.     

Periprosthetic joint infection after primary TKA in the medicare population: How frequently are patients revised at a different hospital?

BackgroundPeriprosthetic infection (PJI) after total knee arthroplasty (TKA) places a significant burden on hospitals. We sought to describe the proportion of patients undergoing revision for PJI at a different hospital within one year of primary TKA and whether patient characteristics or hospital volume were associated with this change.MethodsMedicare data from 2005 to 2014 was retrospectively reviewed using PearlDiver. All patients over 64 years undergoing revision for PJI within one year of primary TKA were stratified by the revision occurring within 90 days. Hospitals were grouped by annual TKA volume as Low (<50), Medium (51–100), High (101–200), and Very High (>200). Associations of patient characteristics and hospital volume with revision at a different hospital were assessed using Chi-squared tests and Somers' D.ResultsOf 8,337 patients undergoing revision within 90 days of TKA, 1,370 (16%) were revised at a different hospital. Changing hospitals was associated with having primary TKA at a lower volume hospital (24% for low, 15% medium, 12% high, and 12% very high; P < 0.001). Of 7,608 patients undergoing revision between 91 and 365 days, 1,110 (15%) were revised at a different hospital. Changing hospitals was associated with having primary TKA at a lower volume hospital (26% for low, 14% medium, 10% high, and 9% very high; P < 0.001). Changing hospitals was not associated with sex or age.ConclusionPatients frequently undergo revision for PJI at a different hospital, even within 90 days of TKA. Further research is needed to understand these implications of this care pathway shift.     

Role of universal 16S rRNA gene PCR and sequencing in diagnosis of prosthetic joint infection

The etiological diagnosis of prosthetic joint infection (PJI) requires the isolation of microorganisms from periprosthetic samples. Microbiological cultures often yield false-positive and false-negative results. 16S rRNA gene PCR combined with sequencing (16SPCR) has proven useful for diagnosing various infections. We performed a prospective study to compare the utility of this approach with that of culture to diagnose PJI using intraoperative periprosthetic samples. We analyzed 176 samples from 40 patients with PJI and 321 samples from 82 noninfected patients using conventional culture and 16SPCR. Three statistical studies were undertaken following a previously validated mathematical model: sample-to-sample analysis, calculation of the number of samples to be studied, and calculation of the number of positive samples necessary to diagnose PJI. When only the number of positive samples is taken into consideration, a 16SPCR-positive result in one sample has good specificity and positive predictive value for PJI (specificity, 96.3%; positive predictive value, 91.7%; and likelihood ratio [LR], 22), while 3 positive cultures with the same microorganism are necessary to achieve similar specificity. The best combination of results for 16SPCR was observed when 5 samples were studied and the same microorganism was detected in 2 of them (sensitivity, 94%; specificity, 100%; and LR, 69.62). The results for 5 samples with 2 positive cultures were 96% and 82%, respectively, and the likelihood ratio was 1.06. 16SPCR is more specific and has a better positive predictive value than culture for diagnosis of PJI. A positive 16SPCR result is largely suggestive of PJI, even when few samples are analyzed; however, culture is generally more sensitive.     

Avoidance of intramedullary violation in computer-assisted total knee arthroplasty lowers the incidence of periprosthetic joint infection compared with conventional total knee arthroplasty: A propensity score matching analysis of 5342 cases

BackgroundConventional total knee arthroplasty (CONV-TKA) inevitably perturbs femoral medullary canal, disturbs medullary micro-architecture and increases blood loss and inflammatory responses. We hypothesized that avoidance of intramedullary violation may lower the incidence of periprosthetic joint infection (PJI). The aim of this study was to verify whether computer-assisted total knee arthroplasty (CAS-TKA) lowers the incidence of PJI as compared with CONV-TKA.MethodsA propensity score matching study of 5342 patients who underwent CAS-TKA (n = 1085) or CONV-TKA (n = 4257) for primary osteoarthritis of the knee from 2007 to 2015 in our institute was performed. Patients who underwent CAS-TKA were matched to those who received CONV-TKA at a 1:2 ratio according to demographics and comorbidities. PJI was defined according to the Musculoskeletal Infection Society diagnostic criteria from the 2013 International Consensus Meeting.ResultsAfter controlling potential risk factors, the use of CAS-TKA resulted in a lower incidence of PJI as compared with CONV-TKA [adjusted hazard ratio (HR), 0.42; 95% confidence interval (CI), 0.18–0.99]. The same trend in PJI reduction was observed with the usage of CAS-TKA under sensitivity testing [HR, 0.33; 95% CI, 0.12–0.95]. The cumulative incidence of PJI was lower in the CAS-TKA group than the CONV-TKA group (log-rank test, p = 0.013).ConclusionAvoidance of intramedullary violation during TKA may play a pivotal role in lowering the incidence of PJI. The use of CAS-TKA can reduce the incidence of PJI, with a better survival rate in terms of being free of PJI, as compared with CONV-TKA.Level of evidence III.     

血清学炎性指标作为早期诊断关节置换术后假体周围感染的研究现状

作为人工关节置换术后的灾难性并发症,关节假体周围感染目前尚无完美的敏感性和特异性血清学炎性指标。所以假体周围感染的早期诊断依然是骨科医师面对的挑战。本文筛选了目前临床用于人工关节假体周围感染的一些血清学炎性指标,予以综述。希望为临床骨科医师早期诊断人工关节假体周围感染提供参考。     

Molecular diagnostics in periprosthetic joint infection

Periprosthetic joint infection (PJI) is a significant and costly challenge to the orthopedic community. The lack of a gold standard for diagnosis remains the biggest obstacle in the detection and subsequent treatment of PJI. Molecular markers in the serum and joint fluid aspirate hold immense promise to enhance the development of a firm diagnostic criterion. The primary goal is one marker with high sensitivity and specificity. Here, we review our current research efforts in the field of molecular markers: C-reactive protein, erythrocyte sedimentation rate, white blood cells, and leukocyte esterase. Each marker has been studied to determine its sensitivity, specificity, and positive and negative predictive values in diagnosing PJI.     

Prosthetic joint infection of the knee - arthroscopic biopsy identifies more and different organisms than aspiration alone

BackgroundProsthetic joint infection (PJI) causes significant morbidity and mortality following knee replacement surgery. Identifying causative organisms and antibiotic sensitivities is critical in increasing the chance of infection eradication. This study investigated whether biopsy alone was superior to aspiration alone for serological diagnosis in PJI following knee replacement. Secondly, we investigated whether biopsy identifies the same or new/different microbiological flora as aspiration.MethodsSince December 2014, the Exeter Knee Reconstruction Unit (EKRU) has prospectively collated data regarding all PJIs referred from our local/regional network which have been reviewed via our Multi-Disciplinary Team (MDT). We identified and included consecutive patients from this MDT from Dec.2014-Mar.2020 and analysed their electronic records. Statistical analysis was performed using Stata.Results65/100 patients studied had both pre-operative aspiration and biopsy. 31/65 (48%) had positive aspiration and biopsies. No aspirate samples were positive with corresponding biopsies negative. In 19/65 (29%) of infection positive patients, biopsy identified new (7) or additional (12) organisms not identified by aspiration. Aspiration had a sensitivity of 70%, specificity of 88%, positive predictive value of 90.3% and negative predictive value of 64.7%. Biopsy had a sensitivity of 97.5%, specificity of 88%, positive predictive value of 92.9% and negative predictive value of 95.7%.ConclusionIn 29% of confirmed PJI cases, arthroscopic biopsy identified either additional organisms in a polymicrobial PJI when compared to aspiration, or new positive results when aspiration alone was negative. This study demonstrates the benefits of arthroscopic biopsy for serological diagnosis in cases of knee PJI and aids treatment planning.     

Autotransfusion with predeposit-haemodilution and perioperative blood salvage: 20 years of experience. Rizzoli Study Group on Orthopaedic Anesthesia.

BACKGROUND: Through a prospective study, we evaluated the efficacy of an integrated autotransfusion regimen comprised of predeposit-hemodiluition and intra and post-operative blood salvage in major orthopaedic surgery. METHODS: We examined the records of 2303 consecutive patients (1524 females and 779 males, mean age 62.7, standard deviation 11 years (range 16-90 yrs), pre-operative haemoglobin (Hb) concentration 13.5 (SD 1.4) (range 6.7-19.3) g/dl undergong total hip arthroplasty (THA 1582 patients), THA after the removal of internal fixation devices (RFD+THA, 25 patients), total knee arthroplasty (TKA, 347 patients), revision surgery of the hip (HR, cup+stem revision, 248 patients; cup revision 64 patients; stem revision 23 patients) and total knee revision (TKR 14 patients). We estimated that the number of predonations (MSBOS - maximum surgery blood order schedule) was 2 units for THA, TKA and TKR, and 3 units for partial or total hip revision and for total hip arthroplasty with fixation removal. RESULTS: It was possible to obtain the MSBOS in 2070 patients (89.8%). Homologous red blood cell (HRBC) transfusion were carried out in 184 patients (8%). We found that the need to use HRBC was significantly associated with failure to meet the number of MSBOS, female sex, lower pre-operative Hb concentration, use of calcium heparin for antithrombosis prophylaxis, more extensive surgery, a higher ASA rating and co-existing diseases such as coronary artery disease. CONCLUSIONS: Cooperation among anaesthesis, transfusionists and surgeons in the application of an integrated autotransfusion regimen enabled us to treat 92% of our patients with only autotransfusion.     

多模式血液管理策略在初次单侧膝、髋关节置换术中的临床应用

目的 评估多模式血液管理策略在初次单侧膝、髋关节置换术(TKA/THA)围手术期应用对减少患者围手术期输血率的有效性及安全性 。方法 纳入2015年11月—2016年10月在第四军医大学西京医院关节外科行初次单侧TKA/THA,应用多模式血液管理策略的403例患者资料为观察组(TKA 285例、THA 118例)进行前瞻性研究;收集2014年6月—2015年10月行初次单侧TKA/THA的582例患者资料为对照组(TKA 393例、THA 189例)进行对照研究,两组患者年龄、性别、BMI、术前血常规检验结果等比较,差异均无统计学意义(P值均>0.05)。两组患者均接受TKA或THA,术中均取1 g氨甲环酸行关节内注射;观察组患者另在围术期行多模式血液管理。比较两组患者围手术期输血率、Hb最大下降值、手术失血量、引流量,以及深静脉血栓、肺栓塞及其他严重术后并发症发生率。结果 术后观察组与对照组输血率分别为1.2%(5/403)和8.2%(48/582),两组中TKA患者输血率分别为0.7%(2/285)和6.9%(27/393)、THA患者输血率分别为2.5%(3/118)和11.8%(21/189),差异均有统计学意义(χ²=22.962、15.353、7.402, P值均<0.01)。TKA术后观察组与对照组患者Hb最大下降值分别为(29.62±11.36)g/L和(34.37±12.88)g/L,THA患者分别为(33.29±11.56)g/L和(37.14±9.42)g/L,两组间比较差异均有统计学意义(t'=5.078、3.042, P值均<0.01);两组TKA患者手术失血量分别为(91.35±58.79) mL和(157.90±71.35) mL,THA患者手术失血量分别为(172.42±65.64) mL和 (246.12±87.89) mL,差异均有统计学意义(t'=13.271、8.378, P值均＜0.01)。深静脉血栓发生率观察组为0.74%(3/403)、对照组为0.85%(5/582),差异无统计学意义(χ²=0.039, P>0.05)。结论 采用多模式血液管理策略可明显降低初次膝、髋置换患者的术后异体输血率,提高患者术后血红蛋白水平,并且不会增加术后并发症的发病率。     

Miliary tuberculosis with delayed-onset total knee arthroplasty Mycobacteria tuberculosis infection successfully treated with medical therapy alone: A case report and literature review

Tuberculosis (TB) affecting a prosthetic knee is an unusual and diagnostically challenging presentation of this disease. This study reported a case of an 80-year-old man with a left total knee arthroplasty (TKA) performed eight years before his presentation. He presented with left knee swelling and pain for one month. Knee X-rays showed a normal joint space with no loosening of his prosthesis. His chest X-ray showed miliary disease, and microbiological studies of his sputum and synovial fluid aspirate grew Mycobacteria tuberculosis complex. He was successfully medically treated with anti-tuberculous therapy alone for one year. His knee hardware was retained, and he did not require debridement, resection, or revision. It is believed that this is the first reported case of miliary TB with delayed-onset TKA prosthetic joint infection (PJI) in which the prosthesis was successfully retained. Thirty-eight published TB TKA PJI cases in medical literature were also reviewed.     

Efficacy of antifungal-impregnated cement spacer against chronic fungal periprosthetic joint infections after total knee arthroplasty

Background

Although two-stage exchange arthroplasty is considered a treatment of choice for chronic features of fungal PJI (periprosthetic joint infection), there is no consensus for local use of antifungal agent. The purpose of this study was to evaluate the efficacy of antifungal-impregnated cement spacer (AICS).