Eradication rates, risk factors, and implant selection in two-stage revision knee arthroplasty: a mid-term follow-up study

Identifying potential predictive indicators for reimplantation timing in two-stage revision: a meta-analysis and system review

PURPOSE

The two-stage exchange revision represents a pivotal strategy in the management of prosthetic joint infections, wherein the judicious timing of reimplantation serves as a crucial determinant for therapeutic success. At present, attempts have been made to utilize predictive models to establish the optimal timing for reimplantation; however, their predictive accuracy remains unsatisfactory. This inadequacy primarily arises from the lack of dependable predictive indicators, which demonstrate inconsistent effectiveness across various studies and occasionally yield contradictory outcomes. Therefore, identifying solid predictive indicators is in desperate need.

METHODS

Studies reporting outcomes of the two-stage exchange revision till June, 2023 were systematically retrieved, screened and subject to quality analysis. Basic characteristics of these studies were firstly summarized. Subsequently, factors of interest regarding clinical information, blood and body fluid test results, pathogen test results of the recurrent and recurrent-free cohorts were extracted and submitted to a fixed or random effects model. Meanwhile, evaluation of publication bias and sensitivity was performed.

RESULTS

After filtering, a total of 45 studies were finally involved. Pooled analysis suggested that the recurrent cohort exhibited elevated incidences of body mass index (BMI) > 30, smoking and alcohol habits, diabetes, sinus tract, positive culture, and G-, polymicrobial and drug-resistant infections. Additionally, higher levels of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), synovial white blood cell (WBC) count, and polymorphonuclear percentage (PMN%) were observed in the recurrent cohort. On the other hand, the results of D-dimer and fibrinogen were ambiguous, and no difference regarding peripheral WBC count was observed. Forest plots suggested a low risk of publication bias. Besides, sensitivity analysis indicated good stability of the aforementioned indicators, except D-dimer and fibrinogen.

CONCLUSION

To sum up, BMI > 30, smoking and alcohol habits, diabetes, sinus tract, positive culture, and G-, polymicrobial and drug-resistant infections, CRP, ESR, synovial WBC and PMN% exhibited significant differences between recurrent and recurrent-free cohorts. Therefore, these indicators may be considered as potential predictive factors for the further development of a prognostic model that aids the determination of reimplantation timing. Nevertheless, the efficacy of these indicators remains to be further confirmed.

REGISTRATION NUMBER

Prospero ID: CRD42022296568.

Description of reinfection of joint prosthesis after 2-stage replacement (infection of the 2nd stage prosthesis): A multicenter study

INTRODUCTION

Two-stage exchange is the gold standard in the surgical management of prosthetic joint infection (PJI). However, perioperative reinfections (RePJI) can occur to newly inserted prosthesis, which highlights the importance of an adequate antibiotic prophylaxis, although there is scarce evidence in this field. Our objective was to evaluate the characteristics of RePJI, its prognosis and the antibiotic prophylaxis that is commonly used in second-stage surgery.

METHODS

Multicentric retrospective observational study in Spanish hospitals including patients with RePJI between 2009 and 2018.

RESULTS

We included 92 patients with RePJI from 12 hospitals. The most frequent isolated microorganism was Staphylococcus epidermidis in 35 cases (38.5%); 61.1% of staphylococci were methiciliin-resistant. In 12 cases (13%), the same microoganism causing the primary PJI was isolated in RePJI. When comparing with the microbiology of primary PJI, there were more cases caused by Gram-negative bacteria (the most frequent was Pseudomonas spp.) and less by Gram-positive bacteria. Failure occured in 69 cases (75%). There were 43 different courses of antibiotic prophylaxis after the second-stage surgery; the most frequent was a unique preoperative cefazolin dose, but most patients received prophylaxis before and after the second-stage surgery (61 cases).

CONCLUSIONS

The most frequent microorganisms in RePJI are coagulase-negative staphylococci, although Gram-negative bacteria, especially Pseudomonas spp. are also common. There is a significant heterogeneity in antibiotic prophylaxis for a second-stage surgery. ReIPJI treatment has a high failure rate.

Impact of antibiotic prophylaxis in second-stage surgery in joint prosthesis infection treated with two-stage exchange. A multicenter case-control study

INTRODUCTION

After two-stage exchange due to prosthetic joint infection (PJI), the new prosthesis carries a high risk of reinfection (RePJI). There isn`t solid evidence regarding the antibiotic prophylaxis in 2nd-stage surgery. The objective of this study is to describe what antibiotic prophylaxis is used in this surgery and evaluate its impact on the risk of developing RePJI.

METHODS

Retrospective multicenter case-control study in Spanish hospitals. The study included cases of PJI treated with two-stage exchange and subsequently developed a new infection. For each case, two controls were included, matched by prosthesis location, center, and year of surgery. The prophylaxis regimens were grouped based on their antibacterial spectrum, and we calculated the association between the type of regimen and the development of RePJI using conditional logistic regression, adjusted for possible confounding factors.

RESULTS

We included 90 cases from 12 centers, which were compared with 172 controls. The most frequent causative microorganism was Staphylococcus epidermidis with 34 cases (37.8%). Staphylococci were responsible for 50 cases (55.6%), 32 of them (64%) methicillin-resistant. Gram-negative bacilli were involved in 30 cases (33.3%), the most common Pseudomonas aeruginosa. In total, 83 different antibiotic prophylaxis regimens were used in 2nd-stage surgery, the most frequent a single preoperative dose of cefazolin (48 occasions; 18.3%); however, it was most common a combination of a glycopeptide and a beta-lactam with activity against Pseudomonas spp (99 cases, 25.2%). In the adjusted analysis, regimens that included antibiotics with activity against methicillin-resistant staphylococci AND Pseudomonas spp were associated with a significantly lower risk of RePJI (adjusted OR = 0.24; 95% IC: 0.09-0.65).

CONCLUSIONS

The lack of standardization in 2nd-satge surgery prophylaxis explains the wide diversity of regimens used in this procedure. The results suggest that antibiotic prophylaxis in this surgery should include an antibiotic with activity against methicillin-resistant staphylococci and Pseudomonas.

The Use of Oral Antibiotics After Total Joint Arthroplasty: A Critical Analysis Review

» There is conflicting and insufficient evidence that extended oral antibiotic (EOA) therapy prevents infection in high-risk patients undergoing primary total joint arthroplasty (TJA), limiting recommendation for or against the practice.» In the case of aseptic revision TJA, the evidence is also conflicting and limited by underlying confounders, preventing recommendation for use of EOA.» There is fair evidence that use of EOA after debridement antibiotic therapy and implant retention of the prosthesis prolongs infection-free survival, but randomized controlled trials are needed. On the other hand, there is strong evidence that patients undergoing 2-stage revision should receive a period of suppressive oral antibiotics after the second stage.» The optimal duration of EOA in primary TJA, aseptic revision, and debridement antibiotic therapy and implant retention of the prosthesis is unknown. However, there is strong evidence that 3 months of EOA suppression may be appropriate after reimplantation as part of 2-stage exchange arthroplasty.» Complications secondary to EOA are reported to be between 0% and 13.7%, yet are inconsistently reported and poorly defined. The risks associated with antibiotic use, including development of antimicrobial resistance, must be weighed against a possible decrease in infection rate.

A mapping review on preoperative prognostic factors and outcome measures of revision total knee arthroplasty

To map literature on prognostic factors related to outcomes of revision total knee arthroplasty (rTKA), to identify extensively studied factors and to guide future research into what domains need further exploration. We performed a systematic literature search in MEDLINE, Embase, and Web of Science. The search string included multiple synonyms of the following keywords: "revision TKA", "outcome" and "prognostic factor". We searched for studies assessing the association between at least one prognostic factor and at least one outcome measure after rTKA surgery. Data on sample size, study design, prognostic factors, outcomes, and the direction of the association was extracted and included in an evidence map. After screening of 5,660 articles, we included 166 studies reporting prognostic factors for outcomes after rTKA, with a median sample size of 319 patients (30 to 303,867). Overall, 50% of the studies reported prospectively collected data, and 61% of the studies were performed in a single centre. In some studies, multiple associations were reported; 180 different prognostic factors were reported in these studies. The three most frequently studied prognostic factors were reason for revision (213 times), sex (125 times), and BMI (117 times). Studies focusing on functional scores and patient-reported outcome measures as prognostic factor for the outcome after surgery were limited (n = 42). The studies reported 154 different outcomes. The most commonly reported outcomes after rTKA were: re-revision (155 times), readmission (88 times), and reinfection (85 times). Only five studies included costs as outcome. Outcomes and prognostic factors that are routinely registered as part of clinical practice (e.g. BMI, sex, complications) or in (inter)national registries are studied frequently. Studies on prognostic factors, such as functional and sociodemographic status, and outcomes as healthcare costs, cognitive and mental function, and psychosocial impact are scarce, while they have been shown to be important for patients with osteoarthritis.

The Use of Rifampin in Total Joint Arthroplasty: A Systematic Review and Meta-Analysis of Comparative Studies

BACKGROUND

Periprosthetic joint infection (PJI) is a devastating complication of total joint arthroplasty (TJA). Rifampin is an antibiotic with the ability to penetrate bacterial biofilms, and thus has been considered as a potentially important adjunct in the prevention and treatment of PJI. The aim of this systematic review is to evaluate and summarize the use of rifampin in TJA, particularly in the context of PJI.

METHODS

A literature search of all relevant electronic databases was performed. All comparative studies assessing the use of rifampin in the context of TJA were included. Descriptive data are reported, and a meta-analysis was performed using all studies which compared the addition of rifampin to standard care in treating PJI.

RESULTS

A total of 33 studies met inclusion criteria. A meta-analysis of 22 studies comparing the addition of rifampin to standard care for treating PJI found a significant reduction in failure rates (26.0% vs 35.9%; odds ratio 0.61, 95% confidence interval 0.43-0.86). The protective effect of rifampin was maintained in studies which included exchange arthroplasty as a treatment strategy, but not in studies only using an implant retention strategy. Among studies reporting adverse events of rifampin, there was a 20.5% adverse event rate.

CONCLUSION

Overall, rifampin appears to confer a protective effect against treatment failure following PJI. This treatment effect is particularly pronounced in the context of exchange arthroplasty. Further high-level evidence is needed to clarify the exact indications and doses of rifampin which can most effectively act as an adjunct in the treatment of PJI.

LEVEL OF EVIDENCE

Level III, Systematic Review and Meta-Analysis of Level I-III Studies.

Correlation between body mass index and two-stage revision failure of periprosthetic joint infection following total joint arthroplasty: A systematic review and meta-analysis

Background: Although the correlation between body mass index (BMI) and two-stage revision failure of periprosthetic joint infection (PJI) following total joint arthroplasty (TJA) have been frequently reported, the results remain controversial. Therefore, the correlation between them was systematically evaluated and meta-classified in this study. Methods: Literature on the correlation between BMI and two-stage revision failure of PJI following TJA was retrieved in PubMed, Embase and Cochrane Library due May 2020. Stata 13.0 software and Cochrane Collaboration Review Manager software (RevMan version 5.3) were applied to data synthesis, subgroup analysis, analyses of publication bias, and sensitivity. Results: A total of 15 observational studies included 1267 patients, of which 15 studies were included in systematic review and 11 studies in meta-analysis. Eight studies found a correlation between BMI and two-stage revision failure of PJI following TJA, but seven other studies found no correlation. Meta-analysis found that the risk of two-stage revision failure of PJI following TJA significantly boosted by 3.53 times in patients with BMI ≥ 30 kg/m² (OR = 3.53; 95% CI = 1.63-7.64 for the BMI ≥ 30 kg/m² vs. BMI < 30 kg/m²) and the risk of two-stage revision failure of PJI following TJA significantly increased by 2.92 times in patients with BMI ≥ 40 kg/m² (OR = 2.92; 95%CI = 1.06-8.03 for the BMI ≥ 40 kg/m² vs. BMI < 30 kg/m²). The subgroup analysis showed that significant association was observed among the studies performed in TKA (OR = 3.63; 95% CI = 2.27-5.82), but not among those conducted in THA (OR = 3.06; 95% CI = 0.42-22.19). A significant association remained consistent, as indicated by sensitivity analyses. Because there are too few studies that can be combined in the included studies, Egger's and Begg's tests were not performed. Conclusion: Meta-analysis suggests that the risk of two-stage revision failure of PJI following TJA significantly boosted in obese patients. However, because there may be publication bias of this study, combined overall systematically evaluated and meta-analysis results, we cannot yet conclude that BMI is associated with two-stage revision failure of PJI following TJA.

Predictors of failure of two-stage revision in periprosthetic knee infection: a retrospective cohort study with a minimum two-year follow-up

PURPOSE

Despite the standardization of two-stage knee revision protocols, a high percentage of failures still occurs. Identifying the predictors of failure is necessary to determine appropriate management and counsel for patients with a periprosthetic knee infection. This study aimed to identify risk factors predicting the failure, to describe implant survival, and to report the mid-term clinical outcomes of patients undergoing two-stage revision for periprosthetic knee infection.

METHODS

Data of patients who underwent two-stage knee revision from 2012 to 2016 were analyzed, and 108 patients were included. The mean age was 66.6 ± 9.2 years. The mean follow-up was 52.9 ± 15.6 months. Logistic regression was conducted to identify predictors of treatment failure. Kaplan-Meier curves were generated to assess implant survival. Preoperative functional outcomes were compared to those registered at the final follow-up.

RESULTS

Difficult-to-treat infections (OR = 4.2, 95% CI 1.2-14.5, p = 0.025), the number of previous surgeries (OR = 1.8, 95% CI 1.2-2.6, p = 0.005), and the level of tibial bone defect (OR = 2.3, 95% CI 1.1-4.7, p = 0.027) significantly predicted the failure of two-stage knee revision. Survivorship of implants was significantly lower for patients presenting these risk factors (p < 0.05). Mean Knee Society Score improved from 49.0 ± 12.0 to 80.2 ± 13.6 (p < 0.001). Mean Oxford Knee Score improved from 22.2 ± 4.9 to 36.1 ± 6.0 points (p < 0.001).

CONCLUSION

Difficult-to-treat pathogens, the number of previous surgeries, and the level of tibial bone defect were independent risk factors of two-stage knee revision failure. Overall, the two-stage protocol provided a good survival rate and functional outcome.

Outpatient parenteral antibiotic therapy for the treatment of prosthetic knee and hip infections in Belgium, a cost minimization analysis

OBJECTIVES

Prosthetic joint infections (PJI) are treated with prolonged periods of intravenous (IV) antibiotics combined with one or more appropriate surgical procedures. In Belgium, patients receive their IV treatments as inpatients, whereas in other parts of the world similar IV antibiotics can be given as outpatient parenteral antibiotic therapy (OPAT), without jeopardising patient outcomes. The purpose of this paper was to analyse the financial feasibility of OPAT for PJI in Belgium.

METHODS

Patients with PJI treated with a two-stage revision between January 2013 and June 2016 were selected for analysis of in-hospital costs. An OPAT cost simulation was made for comparable lengths of stay, for the different antimicrobial regimens used. A cost minimization analysis comparing the non-OPAT costs and the OPAT cost simulation was performed, with a sensitivity analysis accounting for cost uncertainties.

RESULTS

Based on the financial data of 12 two-stage revisions and 4 different antibiotic regimens, the average simulated cost difference for OPAT was €2.402 surplus for the patient, €-25.950 for health care and €-23.548 in total.

CONCLUSION

Projected cost savings for OPAT-treatment of PJI are substantial. However, OPAT within the current Belgian system was significantly more expensive for the patients. This can be attributed to the Belgian health insurance system; its current reimbursement regulations prevent OPAT from truly making a breakthrough in Belgium.

Systematic review of risk prediction studies in bone and joint infection: are modifiable prognostic factors useful in predicting recurrence?

Background: Classification systems for orthopaedic infection include patient health status, but there is no consensus about which comorbidities affect prognosis. Modifiable factors including substance use, glycaemic control, malnutrition and obesity may predict post-operative recovery from infection. Aim: This systematic review aimed (1) to critically appraise clinical prediction models for individual prognosis following surgical treatment for orthopaedic infection where an implant is not retained; (2) to understand the usefulness of modifiable prognostic factors for predicting treatment success. Methods: EMBASE and MEDLINE databases were searched for clinical prediction and prognostic studies in adults with orthopaedic infections. Infection recurrence or re-infection after at least 6 months was the primary outcome. The estimated odds ratios for the primary outcome in participants with modifiable prognostic factors were extracted and the direction of the effect reported. Results: Thirty-five retrospective prognostic cohort studies of 92 693 patients were included, of which two reported clinical prediction models. No studies were at low risk of bias, and no externally validated prediction models were identified. Most focused on prosthetic joint infection. A positive association was reported between body mass index and infection recurrence in 19 of 22 studies, similarly in 8 of 14 studies reporting smoking history and 3 of 4 studies reporting alcohol intake. Glycaemic control and malnutrition were rarely considered. Conclusion: Modifiable aspects of patient health appear to predict outcomes after surgery for orthopaedic infection. There is a need to understand which factors may have a causal effect. Development and validation of clinical prediction models that include participant health status will facilitate treatment decisions for orthopaedic infections.

Two-stage exchange Arthroplasty for knee Periprosthetic joint infection exhibit high infection recurrence rate in patients with chronic viral hepatitis

BACKGROUND

Currently, there is little evidence about the outcome of two-stage exchange arthroplasty for the treatment of knee periprosthetic joint infection (PJI) in patients with chronic viral hepatitis. To evaluate it, we set the primary outcome as infection recurrence, and the secondary outcome as the difference between patients diagnosed with hepatitis B virus or hepatitis C virus.

PATIENTS AND METHODS

Between June, 2010 and December, 2016, 172 patients with knee PJIs were treated with two-stage exchange arthroplasty at our institute. Treatment success was defined using Delphi-based consensus. These patients were further divided into groups with or without chronic hepatitis. Variables were analyzed, including age, sex, comorbidities, microbiology, and operative methods. Minimum follow-up was 12 months (mean, 35 months; range, 12-85 months).

RESULTS

Of the 172 knee PJI patients, 25 were identified with chronic hepatitis. The infection recurrence rate in the hepatitis group (28%, 7 in 25) was significantly higher than that in the non-hepatitis group (9.5%, 14 in 147), p = 0.017. However, there was no significant difference in the infection recurrence rates between patients with HBV (24%, 4 in 16) and HCV (33.3%, 3 in 9). Regarding the outcomes of patients with infection recurrence, 4 of the non-hepatitis patients were treated with the debridement, antibiotic treatment, irrigation, and retention of prosthesis (DAIR) procedure, with a success rate of 75%. The other 17 patients (7 with hepatitis and 10 without) were treated with repeated two-stage exchange arthroplasty with 100% infection elimination rate until the final follow-up.

CONCLUSIONS

Knee PJI patients with chronic hepatitis have higher infection recurrence rate after two-stage exchange arthroplasty (28%).

Acute Renal Failure After the First Stage of a 2-Stage Exchange for Periprosthetic Joint Infection

BACKGROUND

Two-stage exchange using antibiotic-loaded spacers is a common approach in treating periprosthetic joint infections. Acute kidney injury (AKIN) can be a systemic complication of this procedure. This study investigates the prevalence of AKIN and identifies potential risk factors.

METHODS

This is a single-center retrospective analysis of patients undergoing 2-stage exchange using a spacer in 285 patients treated between 2010 and 2017. Risk factors were evaluated using parametric and nonparametric analyses and a multivariate, binary logistic regression model.

RESULTS

Thirty-three percent of patients (95/285) developed an AKIN postoperatively. Twenty-four percent (23/95) of these patients had an acute on chronic kidney failure with a previously impaired renal function. In multivariate analysis, a higher age (hazard ratio [HR], 1.034; 95% confidence interval [CI], 1-1.068; P = .046) and a higher baseline creatinine level (HR, 1.94; 95% CI, 1.237-3.052; P = .004) were risk factors for AKIN. Treatment with vancomycin in the spacer or systemically was not associated with AKIN while a high vancomycin blood level (HR, 1.91; 95% CI, 0.913-3.992; P = .086) and fungal infections were (HR, 3.482; 95% CI, 0.968-12.521; P = .056). Furthermore, in univariate analysis, a higher median Charlson comorbidity index (4 vs 3, P = .007), a lower preoperative hemoglobin (10.9 vs 11.7 g/dL, P = .008), and a higher number of blood transfusions (1 vs 0, P = .004) were associated with AKIN.

CONCLUSION

AKIN is common in patients undergoing 2-stage exchange. Associated patient factors, particularly in patients with chronic renal dysfunction, should be optimized. The general use of glycopeptide antibiotics was no risk factor for AKIN.

Do not exchange the spacer during staged TKA exchange!

Purpose

The aim of this study was to investigate the reinfection rate and risk factors for septic failure after two-stage exchange for chronic periprosthetic joint infections of primary total knee arthroplasties. Reinfections should be classified as new infection or as infection recurrence after two-stage exchange.

Methods

We performed a retrospective study of 60 knees with chronic periprosthetic joint infections. Follow-up information was extracted from the departments electronic database.

Results

The reinfection rate after a mean follow-up of 35.6 months (1–135) was 20.0%. The only significant risk factor for reinfection was spacer exchange during two-stage exchange (OR = 10.42; p = 0.001). Of the 12 cases with reinfection 6 cases were classified as new infection and 2 as infection recurrence.

Conclusions

Patient specific factors for reinfection remain furtive. If a spacer exchange is preformed, the risk of reinfection increases. Culture results indicate that the benefit of spacer exchanges during two-stage exchange is highly questionable, particularly because reinfection is an issue of new infection rather than of infection recurrence.

Diagnostic value of the CD 15 focus score in two-stage revision arthroplasty of periprosthetic joint infections : High specificity in diagnosing infect eradication

INTRODUCTION

The purpose of this study is to use the CD15 focus score (FS) to determine the sensitivity and specificity of bacterial infection persistence in spacer-based two-stage revision arthroplasty.

METHODS

The analysis comprises 112 cases that were subjected to revision due to the presence of infection upon replacement of a joint endoprosthesis. The histopathological data were collected in accordance with the synovial-like interface membrane (SLIM) classification and the CD15-FS and correlated with the microbiological data (MD). The quantifying evaluation of the CD15-FS was performed without knowledge regarding the microbiological data (MD). Correlation with the MD was performed after a 14-day cultivation period.

RESULTS

With a single evaluation (1 focus, field area: 1.2 mm2) with a score value of 42, the CD15-FS showed a sensitivity for the eradication of infections of 0.64 and a specificity of 0.79 (PPV = 0.5; NPV = 0.87). With tenfold evaluation (10 foci, field area: 12 mm2) with a score value of 220, the sensitivity for the eradication was 0.68, the specificity 0.91 (PPV = 0.7; NPV = 0.89). No statistically significant correlation between the score values and the different infectious species could be detected. Based on the MD in 112 cases the rate of infection eradication was 75%. Polymethylmethacrylate-particles (PMMA) were detected in the perispacertissue in 64 cases (58%). No significant correlation could be established between microbiological pathogen detection and the presence of PMMA.

CONCLUSION

In all cases (n = 112), periimplant synovial tissue (SLIM) with variable fibroblastic cellularity, capillary proliferation, leukocytic infiltration, fibrin deposition, new formation of woven bone and detection of PMMA particles was observed. These cases were classified as type IX perispacer synovialis/SLIM: type IX‑A with histopathological infection eradication and type IX‑B with histopathological infection persistence.

Reinfection and re-revision rates of 113 two-stage revisions in infected TKA

Introduction: Two-stage revision is the most frequently performed revision procedure of a (suspected) periprosthetic joint infection (PJI) after total knee arthroplasty (TKA). The reported results of this treatment show large variability between studies, ranging between 0 - 40 percent failure. The purposes of this study were to determine long term (1) reinfection rate, (2) re-revision rates for any reason, and (3) the reinfection rate of patients with positive cultures at reimplantation.

Methods: We prospectively followed and retrospectively reviewed 113 consecutive two-stage revision TKAs, performed between 2003 and 2013 in our clinic with a minimum follow-up of 2 years. Diagnosis of PJI was based on the major Musculoskeletal Infection Society criteria for PJI.

Results: After a mean follow-up of 94 months (range 24-172 months), infection recurred in 23 cases (23%). Of these, nine cases (9%) were defined as relapse (same micro-organism as index revision) and in 14 cases another causative was found (14%). In 11 patients debridement, antibiotics and retention of the prosthesis successfully eradicated the reinfection. After overall follow-up 17 patients (17%) underwent re-revision surgery, 11 patients (11%) due to an infection and 6 patients (6%) for aseptic reasons.

Conclusions: Treatment of a (suspected) infection of a TKA by a two-stage revision had acceptable results based on re-revision and re-infection rates in the long term (>5 years), resembling the short-term results (<2 years). Focussing on the cultures at the index two-stage revision, episodes of relapse and new infections during follow-up were almost equally divided. Reinfection rates were higher in cases with positive cultures at reimplantation. Patients should be counselled appropriately in this particular situation.

One-Stage Arthroplasty or Revision for Seronegative Infections in Hip and Knee

Objective

To assess the safety and effectiveness of one‐stage total joint arthroplasty (TJA) or revision for seronegative infections after total hip arthroplasty (THA) and total knee arthroplasty (TKA).

Methods

This retrospective study included a total of 495 patients who had undergone one‐stage total joint (hip or knee) arthroplasty or revision with a diagnosis of osteoarthritis secondary to sepsis, osteoarthritis or osteonecrosis of the femoral head (ONFH) secondary to internal fixation surgery of the hip joint, and one‐stage revision for prosthesis loosening after THA or TKA from January 2012 to December 2016. Bacterial cultures were taken from all patients (from joint fluid or articular cavity fluid and four to six different parts of soft tissues) during the operation. If the cultures were positive, patients received antibiotic treatment. Microbiology results from surgical samples, clinical evaluations, SF‐12 score (physical component summary [PCS] and mental component summary [MCS]), Harris hip score (HHS) or Hospital for Special Surgery (HSS) score, and patients' satisfaction was recorded at every follow‐up session.

Results

A total of 24 patients had a positive result for bacterial culture (4.85%). The bacterial culture results showed that there were 19 cases (79.16%) of gram‐positive cocci (Staphylococcus aureus), 4 cases (16.67%) of gram‐negative bacilli, and 1 case (4.17%) of fungi. For at least 24 months (mean 35 months) follow‐up, no reinfection was discovered. The mean HHS or HSS score improved significantly from 36.29 points preoperatively to 84.21 points postoperatively (P < 0.001). The mean PCS score improved from 10.15 preoperatively to 20.34 postoperatively, and the mean MCS from 13.22 preoperatively to 21.76 postoperatively, with significant differences. Most of the patients were satisfied.

Conclusion

One‐stage arthroplasty or revision with exhaustive debridement, adequate dosage, and duration of sensitive antibiotics is safe and effective for patients who have seronegative infection of hip or knee joints.

Predictors of Treatment Failure for Hip and Knee Prosthetic Joint Infections in the Setting of 1- and 2-Stage Exchange Arthroplasty: A Multicenter Retrospective Cohort

Background

Prosthetic hip and knee joint infections (PJIs) are challenging to eradicate despite prosthesis removal and antibiotic therapy. There is a need to understand risk factors for PJI treatment failure in the setting of prosthesis removal.

Methods

A retrospective cohort of individuals who underwent prosthesis removal for a PJI at 5 hospitals in Toronto, Canada, from 2010 to 2014 was created. Treatment failure was defined as recurrent PJI, amputation, death, or chronic antibiotic suppression. Potential risk factors for treatment failure were abstracted by chart review and assessed using a Cox proportional hazards model.

Results

A total of 533 individuals with prosthesis removal were followed for a median (interquartile range) of 814 (235–1530) days. A 1-stage exchange was performed in 19% (103/533), whereas a 2-stage procedure was completed in 88% (377/430). Treatment failure occurred in 24.8% (132/533) at 2 years; 53% (56/105) of recurrent PJIs were caused by a different bacterial species. At 4 years, treatment failure occurred in 36% of 1-stage and 32% of 2-stage procedures (P = .06). Characteristics associated with treatment failure included liver disease (adjusted hazard ratio [aHR], 3.12; 95% confidence interval [CI], 2.09–4.66), the presence of a sinus tract (aHR, 1.53; 95% CI, 1.12–2.10), preceding debridement with prosthesis retention (aHR, 1.68; 95% CI, 1.13–2.51), a 1-stage procedure (aHR, 1.72; 95% CI, 1.28–2.32), and infection due to Gram-negative bacilli (aHR, 1.35; 95% CI, 1.04–1.76).

Conclusions

Failure of PJI therapy is common, and risk factors are not easily modified. Improvements in treatment paradigms are needed, along with efforts to reduce orthopedic surgical site infections.

The Presence of Sinus Tract Adversely Affects the Outcome of Treatment of Periprosthetic Joint Infections

BACKGROUND

A sinus tract may be encountered in patients with periprosthetic joint infection (PJI) and constitutes a major criterion for diagnosis. The aim of this study is to identify associated factors for the presence of sinus tract and outcome of 2-stage exchange arthroplasty in these patients.

METHODS

We retrospectively reviewed all patients with PJI following hip and knee arthroplasty from 2000 to 2017. Of them, 161 patients with a sinus tract had a minimum follow-up of 1 year following 2-stage exchange arthroplasty. These patients were matched 1:2 with those without sinus tract by using propensity score matching. Treatment success was assessed using the modified Delphi criteria. A multiple logistic regression analysis was performed to determine the effect of sinus tract on the outcome and associated factors for the presence of sinus tract.

RESULTS

Factors significantly associated with sinus tract included smoking (odds ratio [OR] = 1.83), hypothyroidism (OR = 1.62), hypoalbuminemia (OR = 1.52), hip joint involvement (OR = 1.43), and prior revision surgery (OR = 1.37). Patients with sinus tract had a significantly higher rate of failure compared to those without sinus tract (OR = 2.94).

CONCLUSION

This study demonstrates that the presence of sinus tract in patients with PJI adversely affects the outcome of treatment of these patients. The presence of sinus tract may be a proxy for other issues such as poor periarticular soft tissue, the poor nutritional status of the host, and multiple prior operations. These findings need to be borne in mind when treating patients with PJI and a concomitant sinus tract.

Are All Periprosthetic Joint Infections the Same? Evaluating Major vs Minor Criteria

BACKGROUND

The diagnosis of periprosthetic joint infection (PJI) can be made when 1 major criterion or 3 of 5 minor criteria are present. However, the outcomes of patients with a major vs minor criteria for diagnosis have not been studied. The objective of this study was to evaluate if a difference in outcome of surgical intervention existed between patients with PJI who were diagnosed with a major criterion or a combination of minor criteria.

METHODS

A retrospective chart review identified 277 primary total hip or knee arthroplasty patients who had developed PJI based on the International Consensus Meeting definition. Patients were further stratified into "major" vs "minor" groups. Patient demographics, PJI workup, surgical treatment, microbiological growth, and clinical outcomes were recorded. Treatment success was defined by using the Delphi criteria. Standard statistical analysis was performed.

RESULTS

Overall, 34 patients met minor-only criteria (12.2%), whereas 243 met major criteria. Of the minor-only patients, 16 (47%) were culture negative. When controlling for confounding variables, there was no statistically significant difference with regard to treatment success (minor 94.1% vs major 82.3%, P = .085) between groups at final follow-up (mean 110 months, range 2.3-567 months). Only higher Charlson comorbidity index (P = .001) and an initial 2-stage surgical procedure (P = .003) were associated with decreased treatment success.

CONCLUSION

PJI patients were similar between both criteria groups, and there was no difference in treatment success as defined by the Delphi criteria between minor-only PJI and major criteria PJI patients.

Serum biomarkers in periprosthetic joint infections

OBJECTIVES

The diagnosis of periprosthetic joint infection (PJI) is difficult and requires a battery of tests and clinical findings. The purpose of this review is to summarize all current evidence for common and new serum biomarkers utilized in the diagnosis of PJI.

METHODS

We searched two literature databases, using terms that encompass all hip and knee arthroplasty procedures, as well as PJI and statistical terms reflecting diagnostic parameters. The findings are summarized as a narrative review.

RESULTS

Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were the two most commonly published serum biomarkers. Most evidence did not identify other serum biomarkers that are clearly superior to ESR and CRP. Other serum biomarkers have not demonstrated superior sensitivity and have failed to replace CRP and ESR as first-line screening tests. D-dimer appears to be a promising biomarker, but more research is necessary. Factors that influence serum biomarkers include temporal trends, stage of revision, and implant-related factors (metallosis).

CONCLUSION

Our review helped to identify factors that can influence serum biomarkers' level changes; the recognition of such factors can help improve their diagnostic utility. As such, we cannot rely on ESR and CRP alone for the diagnosis of PJI prior to second-stage reimplantation, or in metal-on-metal or corrosion cases. The future of serum biomarkers will likely shift towards using genomics and proteomics to identify proteins transcribed via messenger RNA in response to infection and sepsis.Cite this article:Bone Joint Res 2018;7:85-93.

Preoperative chlorhexidine reduces the incidence of surgical site infections in total knee and hip arthroplasty: A systematic review and meta-analysis

OBJECTIVE

This meta-analysis aims to assess the incidences of surgical site infection of patients who applied preadmission chlorhexidine skin preparation, versus those who applied the traditional skin preparation before undergoing total knee and hip arthroplasty.

METHODS

A systematic search is carried out through Medline (1966-2016.11), PubMed (1966-2016.11), Embase (1980-2016.11), ScienceDirect (1985-2016.11) and the Cochrane Library. Only high quality studies are identified. Meta-analysis is conducted with the use of Stata 11.0 software.

RESULTS

One RCT and five retrospective studies, published between 2010 and 2016, are included in the present meta-analysis. The present meta-analysis indicates that there are significant differences in surgical site infection rate (RD = -0.02, 95% CI: -0.02 to -0.01, P < 0.00001), revision surgery rate (RD = -0.01, 95% CI: -0.01 to -0.01, P < 0.00001) and length of stay (MD = -0.29, 95% CI: -0.48 to -0.11, P = 0.002) between groups.

CONCLUSION

Preoperative chlorhexidine skin preparation appears to reduce the risk of infection, the incidence of revision surgery, and the length of stay for patients undergoing total knee and hip arthroplasty. No adverse effects, such as DVT or PE, appear to be related to chlorhexidine preparation. Due to the limited quality of the evidence currently available, high quality RCTs with better study designs, larger sample sizes and longer follow-ups are needed.