Prosthetic joint infection risk after total hip arthroplasty in the Medicare population

Risk factors for infection in patients undergoing hip replacement: a systematic review and meta-analysis

A meta-analysis was conducted to determine the risk of infection following hip replacement and risk factors were identified for surgical site infection. PubMed/Medline, Embase and Cochrane Library databases were systematically searched, as well as the reference lists of previous systematic reviews and meta-analyses. The pooled odds ratio (OR) was estimated using a random effects model for each investigated factor. The evidence of observational studies was classified as high quality (class I), moderate quality (class II or III) or low quality (class IV) based on the GRADE system. A total of 25,383 potential articles met the inclusion criteria in the database search. After reviewing the titles, abstracts, and full texts, 27 articles were included in the final analysis, encompassing 699,473 patients who underwent hip arthroplasty. High-quality evidence shows that BMI (≥30 kg/m2) (OR 2.16; 95% CI 1.72-2.70), male sex (OR 1.39; 95% CI 1.26-1.53), operation time (≥120 min) (OR 1.72; 95% CI 1.39-2.14), American Society of Anesthesiologists (ASA) class ≥3 (OR 2.05; 95% CI 1.49-2.83), diabetes (OR 1.33; 95% CI 1.23-1.43), and heart disease (OR 1.99; 95% CI 1.48-2.68) are associated with a greater risk of infection. The meta-analysis revealed that age and renal disease were not associated with infection. In conclusion, this meta-analysis identified significant risk factors for infection after hip-replacement surgery, including BMI, male sex, operation time, heart disease, diabetes, and ASA class.

Have We Succeeded in Reducing the 2-Year Periprosthetic Joint Infection Incidence Rate Following Total Hip Arthroplasty? A National Database Analysis From 2011 to 2019

INTRODUCTION

Current clinical practice guidelines to reduce periprosthetic joint infection (PJI) following total hip arthroplasty (THA) advocate for preventative methods including preoperative antibiotics, nasal decolonization, meticulous antiseptic preparation, and preoperative risk stratification. However, it remains unclear if the implementation of these methods has impacted the incidence of septic revision following THA. Therefore, the purpose of this study was to examine the change in the 2-year incidence rate of septic revisions following THA from 2011 to 2019.

METHODS

A retrospective observational study was performed using a national administrative claims database. The primary outcome was to observe the yearly change in the rates of 2-year incidence of septic revision after THA from 2011 to 2019. Multivariable logistic regression was conducted to compare the incidence of septic revision for each year, using 2011 as the reference year. A linear regression analysis and compounded annual growth rate (CAGR) calculation were conducted to assess the change throughout the study period.

RESULTS

In total, 412,586 patients underwent THA from 2011 to 2019, with an overall 0.43% undergoing septic revision within two years following THA. The rate of septic revision increased from 0.3% in 2011 to 0.5% in 2019 (CAGR: +6.6 %; P < 0.001). After controlling for confounders, comparing the yearly rates to that in 2011, the likelihood of septic revision surgery sequentially increased in 2015 (OR [odds ratio]: 1.34), 2016 (OR: 1.33), 2017 (OR: 1.46), 2018 (OR: 1.47), and 2019 (OR: 1.70) (P < 0.05 for all).

CONCLUSION

Although studies have shown various infectious control modalities to be efficacious in reducing the incidence of septic revision, our study of patients on a national level demonstrates an increase in the rate of 2-year septic revision. Future efforts may focus on creating more targeted prevention strategies against PJI with recent trends in mind.

Low-Volume Surgeons Operating at High-Volume Hospitals Have Low Rates of Periprosthetic Joint Infection After Hip and Knee Arthroplasty

BACKGROUND

The relationship between surgeon and hospital case volumes and postoperative risk following total hip arthroplasty and total knee arthroplasty (THA and TKA) has been described independently. This study aimed to assess the risk of periprosthetic joint infection (PJI) following primary TKA and THA to determine if lower volume surgeons operating at higher volume centers would have lower rates of complications compared to lower volume surgeons operating at lower volume hospitals.

METHODS

A health care database was used to retrospectively identify all primary and elective total joint arthroplasties from October 2015 to December 2021. Using restricted cubic splines, high-volume hospitals were defined using Markov chain Monte Carlo simulation, which identified a volume beyond which PJI rates no longer decreased significantly with increasing hospital volume. A similar methodology was used to identify low-volume surgeons operating in high- and low-volume hospitals. There were 605,254 patients who underwent total joint arthroplasty (THA: 37.71%; TKA: 62.29%) by low-volume surgeons (< 57 THAs and < 68 TKAs) identified and divided into high- and low-volume hospital cohorts. High-volume hospitals were defined as > 508 THA and > 812 TKAs per year, and low-volume hospitals were defined as < 145 THAs and < 243 TKAs per year. Multivariable models accounting for potential confounding covariates were created to determine the odds of PJI between cohorts.

RESULTS

After taking confounding variables into account, low-volume surgeons at high-volume hospitals had lower rates of PJI relative to their counterparts at low-volume hospitals (THA 0.67 versus 0.80%, adjusted odds ratio = 0.69 [95% confidence interval = 0.54 to 0.88], P = 0.002; TKA 0.51 versus 0.69%, adjusted odds ratio = 0.73, [95% confidence interval = 0.61 to 0.87], P = 0.007).

CONCLUSIONS

Increasing institutional case volume may mitigate the increased risk of PJI associated with low annual surgeon case volume.

Medicare Advantage Is Associated With Higher Mortality After Antibiotic Spacer Placement for Periprosthetic Joint Infection

BACKGROUND

Privatized Medicare Advantage (MA) plans are an alternative to traditional Medicare (TM). We sought to identify differences in 90-day postoperative mortality and nonfatal adverse events between TM and MA patients undergoing stage 1 antibiotic spacer placement for periprosthetic joint infection (PJI) of the hip or knee.

METHODS

A nationally representative database was queried from 2015 to 2021 for adult patients undergoing stage 1 antibiotic spacer placement for PJI. Using the International Classification of Disease, 10th Revision, and Current Procedural Terminology codes, as well as hospital charges for antibiotics, patients undergoing stage 1 exchange arthroplasty for PJI were identified. Patients were then grouped into TM and MA cohorts. The primary outcome was the odds of 90-day mortality. Multivariable logistic regressions were conducted to address possible confounding demographic, comorbidity, and hospital characteristics.

RESULTS

Of the 40,346 patients undergoing stage 1 spacer placement for PJI, 16,637 (41.2%) had TM coverage and 9,218 (22.8%) had MA coverage. Mortality within 90 days of surgery was higher in the MA cohort (1.4% versus 1.0%, P = 0.004). Multivariable logistic regression demonstrated significantly higher adjusted odds of mortality (adjusted odds ratio = 1.42, 95% confidence interval = 1.11 to 1.81, P = 0.005) in MA patients compared to TM.

CONCLUSIONS

Even after accounting for available confounders with our multivariable analyses, patients enrolled in an MA plan were more than 40% more likely to die within 90 days of surgery compared to patients who have TM coverage. Further study is necessary to better understand the underlying cause of this finding.

Why Are Contemporary Primary Ceramic-on-Highly Crosslinked Polyethylene Total Hip Arthroplasties Failing? An Analysis of Over 5,500 Cases

BACKGROUND

Ceramic-on-highly crosslinked polyethylene (HXLPE) has become the most common bearing surface utilized in primary total hip arthroplasty (THA). The purpose of this study was to determine the implant survivorship and clinical outcomes of THAs with ceramic-on-HXLPE in a large single-institutional series.

METHODS

We identified 5,536 primary THAs performed from 2007 to 2017 using a ceramic-on-HXLPE bearing through our total joint registry. The mean age was 60 years, 51% were women, and the mean body mass index was 30. A cementless femoral component was used in 98% of cases, and a head size of ≥ 36 was used in 75%. Kaplan-Meier survivorship analyses were completed to assess survivorship free of any revision or reoperation. Clinical outcomes were assessed via Harris Hip Score. The mean follow-up was four years.

RESULTS

The 5-year survivorship free of any revision was 97%. The most common indications for revision were dislocation (41 hips), periprosthetic joint infection (39 hips), and periprosthetic femur fracture (18 hips). The 5-year survivorship free of any reoperation was 96%. There were an additional 70 reoperations, with the most common indications being wound dehiscence (32 hips), iliopsoas impingement (11 hips), and periprosthetic femur fracture (11 hips). There were only two bearing surface failures: one HXLPE liner fractured and one dissociated. There were no ceramic head fractures or failures. The mean Harris Hip Score increased from 57 to 92 (P < 0.0001).

CONCLUSIONS

In over 5,500 THAs completed with modern ceramic-on-HXLPE bearings, failures of the bearing surface were nearly eliminated at midterm follow-up, and overall 5-year survivorship free of revision was excellent. Dislocation, periprosthetic joint infection, and periprosthetic femur fracture were the most common causes of failure. As bearing surfaces have evolved, traditional failure mechanisms such as polyethylene wear, corrosion and metal reactions, and ceramic fractures have become nearly extinct.

LEVEL OF EVIDENCE

III (Case-Control Study), Therapeutic.

Prognostic Value of C-Reactive Protein in Primary Total Hip Arthroplasty

Background/Objectives: Periprosthetic joint infections (PJIs) are feared complications in arthroplasty and are associated with an increased mortality rate. PJI prevention is of paramount importance since treatment is difficult. In case of an infection, it is crucial to diagnose it at an early stage in order to initiate adequate therapy. The Musculoskeletal Infection Society (MSIS) proposed a catalog of different major and minor diagnostic criteria in 2011 to define a PJI. They were adapted in the following years. One of these criteria is the blood level of C-reactive protein (CRP). CRP is a non-specific acute-phase protein that also increases in response to various non-infectious inflammatory responses. CRP is also routinely obtained prior to total hip arthroplasty (THA) to screen for possible contraindications for arthroplasty such as an acute infection. The validity of this approach has rarely been investigated. The aim of this study was to evaluate the diagnostic value of perioperative CRP in patients receiving a THA. Methods: A total of 239 patients were included in this study and retrospectively analyzed. CRP values were obtained preoperatively and three values postoperatively. Sensitivity, specificity, area under the curve (AUC) and optimal thresholds were calculated. Results: In the whole group, 10 patients developed a PJI. No significance was demonstrated between patients without and with later PJI in terms of preoperative CRP (p = 0.182), postoperative CRP (p = 0.167), relative CRP increase (p = 0.684) and respective CRP differences (p = 0.456). We were not able to find cut-off values with adequate sensitivity and specificity. Conclusions: Perioperative CRP values do not seem to be helpful in predicting further PJI. Rather, they should be used as a screening tool to detect ongoing infections in the individual patient prior to THA. This trial should encourage studies with more statistical power due to the small effect sizes.

Reliability and utility of the new Belt et al. classification for revision of infected total knee arthroplasty

INTRODUCTION

The frequency of revisions in total knee arthroplasty (TKA) is rising. Various classifications of bone defects exist, each with its own limitations. Recently, Belt et al. have proposed a new classification for TKA revisions based on X-ray imaging. We evaluated the Belt et al. classification and verified if this new classification is reliable, and if it correlates with the implant used during revision surgery for periprosthetic joint infection.

METHODS

This is a retrospective study. We reproduced the paper proposed by Belt et al. with the radiological data of all patients who underwent two stage revision for infected TKA in our institution between January 2017 and December 2022. Five different operators classified the bone defect for each patient at two time points. Subsequently, we assessed intra- and inter-operator reproducibility. We also collect the surgery data from our registry to verify if there is a correlation between augment use and epiphyseal bone defect.

RESULTS

The classification proposed by Belt is reliable, and have a good reproducibility inter and intraoperator. There is no correlation between the bone defect. And the use of augment, and so this classification is usless in the prediction of the material needed in the operating room.

CONCLUSION

The Belt at al. classification is reliable, but a classification which can predict the implant neded have to be developed.

Machine learning to predict periprosthetic joint infections following primary total hip arthroplasty using a national database

INTRODUCTION

Periprosthetic joint infection (PJI) following total hip arthroplasty (THA) remains a devastating complication for patients and surgeons. Given the implications of these infections and the current paucity of risk calculators utilizing machine learning (ML), this study aimed to develop an ML algorithm that could accurately identify risk factors for developing a PJI following primary THA using a national database.

MATERIALS AND METHODS

A total of 51,053 patients who underwent primary THA between 2013 and 2020 were identified using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Demographic, preoperative, intraoperative, and immediate postoperative outcomes were collected. Five ML models were created. The receiver operating characteristic curves, the area under the curve (AUC), calibration plots, slopes, intercepts, and Brier scores were evaluated.

RESULTS

The histogram-based gradient boosting (HGB) model demonstrated good PJI discriminatory ability with an AUC of 0.88. The test-specific metrics supported the model's performance and validation in predicting PJI (calibration curve slope: 0.79; intercept: 0.32; Brier score: 0.007). The top five predictors of PJI were the length of stay (> 3 days), patient weight at the time of surgery (> 94.3 kg), an American Society of Anesthesiologists (ASA) class of 4 or higher, preoperative platelet count (< 249,890/mm3), and preoperative sodium (< 139.5 mEq/L).

CONCLUSION

This study developed a highly specific ML model that could predict patient-specific PJI development following primary THA. Considering the feature importance of the top predictors of infection, surgeons should counsel at-risk patients to optimize resource utilization and potentially improve surgical outcomes.

Analysis of systemic serum vancomycin levels following intraarticular application in primary total joint arthroplasty

INTRODUCTION

Periprosthetic joint infection (PJI) is a serious complication following primary total joint arthroplasty (TJA). PJI accounts for 15-25% of revision surgeries, therefore it is associated with PJI is associated with substantial patient morbidity and mortality as well as increased healthcare expenditures due to complex treatment strategies. Recently, intraoperative local application of vancomycin powder is increasingly being used in primary total hip and knee arthroplasty (THA, TKA) as an additive strategy for PJI prevention. Whereas local vancomycin concentrations have already been investigated in prior studies, evidence on systemic vancomycin levels and potential adverse drug reactions (ADR) is limited. Purpose of this study was to investigate systemic vancomycin levels following intraarticular application in primary TJA.

MATERIALS AND METHODS

This pilot study is a prospective analysis of patients undergoing primary THA and TKA between April and July 2023. One gram of vancomycin powder was applied to the prosthesis prior to wound closure. Serum vancomycin levels were measured at two standardised time points, 24 and 48 h postoperatively.

RESULTS

In total, 103 patients were included, and the patient collective was further stratified by surgical procedure into a THA subgroup (n = 52) and a TKA subgroup (n = 51). Mean serum vancomycin levels showed a significant group difference at both time points (24 h: p < 0.001; 48 h: p = 0.044) with higher serum vancomycin concentrations in the THA cohort. Mean serum vancomycin levels in THA patients were 1.25 μg/ml (range 0.00-7.00 μg/ml) after 24 h and 0.34 μg/ml (range 0.00-4.80 μg/ml) 48 h postoperatively. In TKA, no systemic vancomycin levels were detected. Vancomycin concentrations did not reach therapeutic levels in any patient. No ADR was detected in the whole study collective.

CONCLUSION

Following intraarticular administration of vancomycin powder, no systemic vancomycin levels within the therapeutic range were detected, thus it may serve as a safe and cost-effective adjunct to strategies for prevention of PJI.

Difficulty of diagnostic accuracy of periprosthetic joint infection: a retrospective analysis of revision surgery of total hip arthroplasty and total knee arthroplasty in a tertiary hospital

BACKGROUND

Diagnostic accuracy of periprosthetic joint infection still remains controversial and an unsolved problem with respect to clinical signs and laboratory measures. Influencing factors of diagnosis like age, sex, abnormal physical findings and comorbidities are published with different results. The aim of our study was to find factors strengthening the diagnosis.

METHODS

We therefore retrospectively investigated all revision surgeries of total knee arthroplasty and total hip arthroplasty in the years 2019 and 2020 in a tertiary hospital with special regard to diagnostic accuracy of periprosthetic joint infection and switch in diagnosis to aseptic mechanical loosening or vice versa. All patients were divided into 4 non-hierarchical groups: suspected and discharge diagnosis periprosthetic joint infection (P1), suspected and discharge diagnosis mechanical loosening (P2), suspected diagnosis mechanical loosening and discharge diagnosis periprosthetic joint infection (P3), suspected diagnosis PJI and discharge diagnosis mechanical loosening (P4).

RESULTS

In the years 2019-2020, 106 patients underwent revision surgery of total knee arthoplasty and total hip arthroplasty. 33 patients showed periprosthetic joint infection (31.1%) according to Infectious Diseases Society (IDSA) criteria, 73 patients showed mechanical loosening (68.9%). Of the periprosthetic joint infection -patients, 15 were men (46%) and 18 were women (54%). The patients with mechanical loosening were 27 men (37%) and 46 women (63%). In group P1 (25 patients), 22 could be classified according to the histopathological classification Krenn and Morawietz grade 2 and grade 3, 2 patients to grade 4 and one patient could not be classified. In group P3 (8 patients) all could be classified according to the classification Krenn and Morawietz grade 2 and 3. Groups P1 - P4 were correlated with categorial basic data: All Groups P1 - P4 showed a statistical correlation towards American Society of Anesthesiologists (ASA) categorization 3-4 versus ASA 2 (p = 0.01). In the pairwise comparison in the exact Fisher´s exact test P1 and P2 showed a statistical correlation towards ASA categorization 3-4 versus ASA 2 (p = 0.01). Charlson Comorbidity Index (CCI) categories 5-7 versus 0,1-2 and 3-4 showed a statistical correlation towards groups P1-P4 (p = 0.007) and in the pairwise comparison in the exact Fisher´s exact test a discrimination of P1 and P2 (p = 0.001) and P1 and P3 (p = 0.007). The preoperative corticoid therapy showed a statistical correlation to groups P1-P4 (p = 0.05) and in the pairwise comparison in the exact Fisher test a discrimination of P1 and P4 (p = 0.02).

CONCLUSION

We therefore conclude that diagnosis of periprosthetic joint infection still remains difficult. Switches in diagnosis during hospital stay from periprosthetic joint infection to aseptic mechanical loosening and vice versa are not unusual and the role of different diagnostic tools needs further investigation. Patients categorized according to ASA and CCI as severely ill might be more likely to be diagnosed correctly with periprosthetic joint infection.

State-of-the-Art Metagenomic Sequencing and Its Role in the Diagnosis of Periprosthetic Joint Infections

Metagenomic next-generation sequencing (mNGS) is increasingly being recognized as a valuable diagnostic tool for periprosthetic joint infections (PJIs). This study reviews the diagnostic utility of mNGS, highlighting its improved sensitivity in detecting pathogens, particularly in culture-negative and polymicrobial infections. However, the clinical application of this method is hindered by challenges such as the prevalence of host DNA, the necessity for extensive bioinformatic analysis, and the potential for contamination, which can lead to misinterpretation of results. As mNGS continues to evolve, it holds significant potential to improve the management of PJI and enhance the application of precision medicine in orthopedic infections.

Success rate of single versus multiple debridement, antibiotics, and implant retention (DAIR) in hip and knee periprosthetic joint infection: a systematic review and meta-analysis

PURPOSE

This systematic review aimed to compare outcomes between multiple and single debridement, antibiotics, and implant retention (DAIR) procedures for early periprosthetic joint infection (PJI) in hip and knee arthroplasty.

METHODS

Four databases were searched from inception till January 2024 for original studies investigating the outcomes of multiple DAIR in hip and knee PJI. The primary outcome was the success rate in eradicating joint infection. This review was conducted per PRISMA guidelines.

RESULTS

A total of 9 observational studies with 1104 participants were included, with a mean age and BMI of 58.37 years (95%CI: 25.77-90.98) and 31.43 kg/m2 (95%CI: 28.89-34.98), respectively. The mean follow-up period was 58.37 months (95%CI: 25.77-90.98), and the average MINORS score assigned to the review was 17.6 ± 3.46, indicating a low overall risk of bias. An equivalent success rate between single and double DAIR was observed, at 67% (95%CI: 64-71%) and 70% (95%CI: 48-86%), respectively, with no statistically significant difference between the two treatment modalities (p = 0.740). Additionally, the success rate for triple DAIR ranged from 50 to 60%.

CONCLUSION

This study suggests that double DAIR is a valid treatment option for acute PJI after TKA and THA, with a success rate comparable to single DAIR (70% vs. 67%, p = 0.740). Triple DAIR achieved success rates ranging from 50 to 60%. However, caution is warranted when interpreting these results due to heterogeneity in host comorbidity factors, DAIR protocols, and antibiotic regimens.

LEVEL OF EVIDENCE

Therapeutic, Level III.

The Epidemiology of the Revision Total Hip Arthroplasty in the United States From 2016 to 2022

Background

The number of revision total hip arthroplasties (THAs) is projected to reach 572,000 cases annually by 2030 in the United States. This may be attributed to the successes of primary THAs combined with an aging population, patients desire to remain active, and expanded indications for younger patients. Given the evolving nature of revision THAs, an epidemiological analysis of (1) etiologies; (2) demographics, including age and region; and (3) lengths of stay (LOSs) may minimize the gap between appropriate understanding and effective intervention.

Methods

From 2016 to 2022, a national, all-payer database was queried. Incidences and indications were analyzed for a total of 102,476 patients who had revision THA procedures. Patients were stratified according to etiology of failure, age, US census region, primary payor class, and mean LOS.

Results

The most common etiologies for revision THA procedures were dislocation (16.7%) and infection (12.7%), followed by periprosthetic fracture (6.9%). The largest age group was 65-74 years (30.9%), followed by >75 years (28.6%), then 55-64 (26.5%). The South had the largest total procedure cohort (36.9%), followed by the Midwest (27.5%), then the Northeast (19.7%), and the West (15.9%). The mean LOS was 4.10 days (range, 1.0-20.0).

Conclusions

Dislocation and infection remain leading indications for revision THA. These findings can properly guide surgeons toward appropriate management as well as toward active steps to minimizing these outcomes.

Comparative performance analysis of Synovasure™ and Leukocyte Esterase assays for the diagnosis of periprosthetic infections in complex microbiological situations

INTRODUCTION

Osteoarticular infections (OAI) after prosthetic surgery have serious functional and economic consequences. Rapid tests for alpha-defensin (TAD) and leukocyte esterase (TLE) are two intra-articular markers involved in the diagnosis of OAIs. TLE cannot be applied in the presence of blood unless centrifugation is used, but the rate of "non-application" of the test for this reason is unknown in complex microbiological situations (discordant or negative puncture, ongoing antibiotic treatment). We therefore conducted a prospective study to determine: 1) the performance of the TAD and TLE rapid tests in diagnosing complex OAI, 2) the rate of non-application of the TLE due to hemarthrosis, and 3) the concordance between the two tests.

ASSUMPTION

These two diagnostic tests had a negative predictive value (NPV) ≥ 90% for the diagnosis of complex OAI.

MATERIALS AND METHODS

A total of 79 suspected OAI patients with complex microbiological diagnoses were included between 2018 and 2023. They were 52 men (66%) for 27 women (34%), with a mean age of 66 ± 13.5 years. The hip (n = 41, 52%) and knee (n = 36, 46%) were the most represented, followed by the elbow (n = 1, 1%) and shoulder (n = 1, 1%). These patients were suspected of having an OAI that required joint puncture, but with a complex microbiological diagnosis due to discordant punctures (n = 21, 27%) or sterile punctures despite strong suspicion of infection (n = 50, 63%), or in case of ongoing antibiotic treatment (n = 8, 10%). All patients underwent joint fluid puncture followed by TAD (Synovasure™, Zimmer, Warsaw, IN, USA) and, when the macroscopic appearance of the sample allowed (clear fluid group), TLE (Multistix 8SG, Siemens Healthcare GmbH, Erlangen, Germany). The results of both tests were compared with Musculoskeletal Infection Society (MSIS) criteria.

RESULTS

Of the 79 patients included, 27 (34%) were considered infected according to the MSIS. In 30% of cases (n = 24), TLE was not feasible due to the presence of blood in the joint fluid. In the "clear fluid" group, the NPV was equal to 90% for both TAD (sensitivity 87%, specificity 88%) and TLE (sensitivity 87%, specificity 81%). The two parameters showed almost perfect agreement (κ = 0.927).

CONCLUSION

TAD and TLE are two rapid, reliable tests with near-perfect concordance and high NPV, even in situations of complex microbiological diagnosis. They are particularly useful for deciding on a therapeutic strategy for patients with complex OAI. The TLE cannot be used in 30% of cases due to hemarthrosis, but centrifugation can correct this defect.

LEVEL OF EVIDENCE

III; Prospective comparative diagnostic accuracy study.

The antimicrobial properties of exogenous copper in human synovial fluid against Staphylococcus aureus

Aims

The mechanism by which synovial fluid (SF) kills bacteria has not yet been elucidated, and a better understanding is needed. We sought to analyze the antimicrobial properties of exogenous copper in human SF against Staphylococcus aureus.

Methods

We performed in vitro growth and viability assays to determine the capability of S. aureus to survive in SF with the addition of 10 µM of copper. We determined the minimum bactericidal concentration of copper (MBC-Cu) and evaluated its sensitivity to killing, comparing wild type (WT) and CopAZB-deficient USA300 strains.

Results

UAMS-1 demonstrated a greater sensitivity to SF compared to USA300 WT at 12 hours (p = 0.001) and 24 hours (p = 0.027). UAMS-1 died in statistically significant quantities at 24 hours (p = 0.017), and USA300 WT survived at 24 hours. UAMS-1 was more susceptible to the addition of copper at four (p = 0.001), 12 (p = 0.005), and 24 hours (p = 0.006). We confirmed a high sensitivity to killing with the addition of exogenous copper on both strains at four (p = 0.011), 12 (p = 0.011), and 24 hours (p = 0.011). WT and CopAZB-deficient USA300 strains significantly died in SF, demonstrating a MBC-Cu of 50 µM against USA300 WT (p = 0.011).

Conclusion

SF has antimicrobial properties against S. aureus, and UAMS-1 was more sensitive than USA300 WT. Adding 10 µM of copper was highly toxic, confirming its bactericidal effect. We found CopAZB proteins to be involved in copper effluxion by demonstrating the high sensitivity of mutant strains to lower copper concentrations. Thus, we propose CopAZB proteins as potential targets and use exogenous copper as a treatment alternative against S. aureus.

Automated design of bone-preserving, insertable, and shape-matching patient-specific acetabular components

Effective treatment of large acetabular defects remains among the most challenging aspects of revision total hip arthroplasty (THA), due to the deficiency of healthy bone stock and degradation of the support columns. Generic uncemented components, which are favored in primary THA, are often unsuitable in revision cases, where the bone-implant contact may be insufficient for fixation, without significant reaming of the limited residual bone. This study presents a computational design strategy for automatically generating patient-specific implants that simultaneously maximize the bone-implant contact area, and minimize bone reaming while ensuring insertability. These components can be manufactured using the same additive manufacturing methods as porous components and may reduce cost and operating-time, compared to existing patient-specific systems. This study compares the performance of implants generated via the proposed method to optimally fitted hemispherical implants, in terms of the achievable bone-implant contact surface, and the volume of reamed bone. Computer-simulated results based on the reconstruction of a set of 15 severe pelvic defects (Paprosky 2A-3B) suggest that the patient-specific components increase bone-implant contact by 63% (median: 63%; SD: 44%; 95% CI: 52.3%-74.0%; RMSD: 42%), and reduce the volume of reamed bone stock by 97% (median: 98%; SD: 4%; 95% CI: 95.9%-97.4%; RMSD: 3.7%).

Antibiotic Prophylaxis for Genitourinary Procedures in Patients with Artificial Joint Replacement and Artificial Heart Valves

Prosthetic joint infection (PJI) and prosthetic valve endocarditis (PVE) are uncommon but serious complications. According to current best practice statements, prior to a genitourinary procedure, patients with prosthetic joints should receive antibiotic prophylaxis if they are within 2 years of arthroplasty, if they are high risk for infection due to their individual comorbidities, or if the procedure poses a high risk for bacteremia. Patients with prosthetic valves should not receive antibiotic prophylaxis for the sole purpose of prevention of endocarditis. Enterococcus species are the uropathogens most often associated with PJI and PVE. Antibiotic selection should take into account local resistance patterns.

Metabolic Syndrome and Morbid Obesity are Not Risk Factors for Revision Surgery in Patients Undergoing Hip and Knee Arthroplasty

BACKGROUND

The effect of metabolic syndrome (MetS) on the risk of revision after hip and knee arthroplasty is debated. The aim of our study was to investigate the risk of short-term (minimum 2.7 years) revision due to periprosthetic joint infection (PJI) after hip and knee arthroplasty. Secondly, we aimed to investigate the risk of revision due to any cause and mortality.

METHODS

During May 2017 to November 2019, a cohort of 2,901 patients undergoing a total of 3,024 hip and knee arthroplasties was established. In the cohort, 62.1% met the criteria for MetS. Data from national registries and a local database were used to determine the presence of MetS and revision surgeries, with a follow-up of at least two years and eight months. Cox regression was applied to the present hazard ratio (HR), associated 95% confidence intervals, and P values. Survival analyses were presented in a Kaplan-Meier plot.

RESULTS

The risk of PJI (HR 1.6 (0.5 to 4.9), P = .380), any revision (HR 0.8 (0.4 to 1.3), P = .295), and death (HR 1.3 (0.8 to 2.1), P = .282) was not increased in patients suffering from MetS compared with patients who did not have MetS. There was no PJI in patients not having MetS and receiving a knee arthroplasty. The risk of death was increased in the MetS group receiving a knee arthroplasty (HR 2.7 (1.3 to 5.9), P = .010), but not different from the MetS group receiving a hip arthroplasty. There was no elevated risk of PJI when analyzing morbid obesity (body mass index over 40), men, or diabetes as the exposures.

CONCLUSIONS

Patients suffering from MetS do not have an increased risk of revision caused by PJI. In general, performing hip and knee arthroplasty in patients suffering from MetS is without increased risk of revision surgery.

Association Between Periprosthetic Joint Infection and Mortality Following Primary Total Hip Arthroplasty

BACKGROUND

Periprosthetic joint infection (PJI) remains a dreaded and unpredictable complication after total hip arthroplasty (THA). In addition to causing substantial morbidity, PJI may contribute to long-term mortality risk. Our objective was to determine the long-term mortality risk associated with PJI following THA.

METHODS

This population-based, retrospective cohort study included adult patients (≥18 years old) in Ontario, Canada, who underwent their first primary elective THA for arthritis between April 1, 2002, and March 31, 2021. The primary outcome was death within 10 years after the index THA. Mortality was compared between propensity-score-matched groups (PJI within 1 year after surgery versus no PJI within 1 year after surgery) with use of survival analyses. Patients who died within 1 year after surgery were excluded to avoid immortal time bias.

RESULTS

A total of 175,432 patients (95,883 [54.7%] women) with a mean age (and standard deviation) of 67 ± 11.4 years underwent primary THA during the study period. Of these, 868 patients (0.49%) underwent surgery for a PJI of the replaced joint within 1 year after the index procedure. After matching, patients with a PJI within the first year had a significantly higher 10-year mortality rate than their counterparts (11.4% [94 of 827 patients] versus 2.2% [18 of 827 patients]; absolute risk difference, 9.19% [95% confidence interval (CI), 6.81% to 11.6%]; hazard ratio, 5.49 [95% CI, 3.32 to 9.09]).

CONCLUSIONS

PJI within 1 year after surgery is associated with over a fivefold increased risk of mortality within 10 years. The findings of this study underscore the importance of prioritizing efforts related to the prevention, diagnosis, and treatment of PJIs.

LEVEL OF EVIDENCE

Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

No shortening of the patellar tendon during two-stage total knee arthroplasty revision using articulating spacers

BACKGROUND

Surgical techniques in two-stage revision total knee arthroplasty (rTKA) include the use of articulating spacers and static spacers. Shortening of the patellar tendon could be a reason for inferior functional outcomes in two-stage septic rTKA . The aim of this study was to determine if articulating spacers also have negative effects on the extensor mechanism in rTKA.

METHODS

This retrospective study includes 65 consecutive patients (23 women, 42 men, age 71.3 ± 1.2; range, 51.2-88.6 years) undergoing septic two-stage rTKA using an articulating spacer between 2014 and 2021 in a single orthopedic center. For all patients, calibrated true lateral radiographs before total knee arthroplasty (TKA) explantation (T0), directly after TKA explantation (T1), shortly before TKA reimplantation (T2) and 6-8 days after TKA reimplantation (T3) were used to calculate the modified Insall Salvati ratio (mISR).

RESULTS

Overall, the mISR decreased significantly immediately after explantation (T0 vs. T1, p = 0.002) from 1.43 ± 0.03 to 1.36 ± 0.03 and remained stable until T2 (1.37 ± 0.02, p = 0.74). Following TKA reimplantation, the mISR increased again to 1.43 ± 0.03 (T3). There were no significant differences between T0 and T3 (p = 0.88). Six out of 65 patients (9%) experienced patellar tendon shortening > 10% at T3.

CONCLUSIONS

Septic two-stage revision TKA using an articulating spacer does not lead to patellar tendon shortening in the majority of cases. This study suggests that one reason for the improved range of motion after reimplantation may be the use of articulating spacers compared to static spacers.

Patient-Related Predictors of Treatment Failure After Two-Stage Total Hip Arthroplasty Revision for Periprosthetic Joint Infection: A Systematic Review and Meta-Analysis

BACKGROUND

Periprosthetic joint infection (PJI) treatment has high failure rates even after 2-stage revision. Risk factors for treatment failure (TF) after staged revision for PJI are not well defined, nor is it well established how they correlate with the risks of developing an index PJI. Identifying modifiable risk factors may allow preoperative optimization, while identifying nonmodifiable risk factors can influence surgical options or advise against further surgery. We performed a systematic review and meta-analysis to better define predictors of TF in 2-stage revision for PJI.

METHODS

The PubMed, Embase, and Scopus databases were searched from their inception in December 1976 to April 15, 2023. Studies comparing patient-related variables between patients successfully treated who had 2-staged revision total hip arthroplasty (THA) and patients with persistent infections were included. Studies were screened, and 2 independent reviewers extracted data, while a third resolved discrepancies. Meta-analysis was performed on these data. There were 10,052 unique studies screened, and 21 studies met the inclusion criteria for data extraction.

RESULTS

There was good-quality evidence that obesity, liver cirrhosis, and previous failed revisions for PJI are nonmodifiable risk factors, while intravenous drug use (IVDU) and smoking are modifiable risk factors for TF after 2-stage revision for hip PJI. Reoperation between revision stages was also significantly associated with an increased risk of TF. Interestingly, other risk factors for an index PJI including male gender, American Society of Anesthesiology score, diabetes mellitus, and inflammatory arthropathy did not predict TF. Evidence on Charlson Comorbidity Index was limited.

CONCLUSIONS

Patients with a smoking history, obesity, IVDU, previous failed revision for PJI, reoperation between stages, and liver cirrhosis are more likely to experience TF after 2-stage revision THA for PJI. Modifiable risk factors include smoking and IVDU and these patients should be referred to services for cessation as early as possible before 2-stage revision THA.

Obesity and Primary Total Hip Arthroplasty: The Absolute versus Relative Risk of Periprosthetic Joint Infection at 15 Years

BACKGROUND

To make an informed decision about total hip arthroplasty (THA), surgeons and patients need to understand the absolute and relative risks of periprosthetic joint infection (PJI). We sought to evaluate the long-term risk of PJI following primary THA stratified by body mass index (BMI) and PJI-related risk factors.

METHODS

We identified 21,550 primary THAs performed from 2000 to 2021 at a single institution. Patients were stratified as having 0, 1, or ≥ 2 PJI risk factors (diabetes, chronic kidney disease, nonprimary osteoarthritis, immunosuppression, or active smoking) and into BMI categories. The 15-year cumulative risk of PJI was evaluated by BMI and PJI risk factors.

RESULTS

For the entire cohort, the 15-year absolute risk of PJI was 2%. For patients who did not have PJI risk factors, the absolute risk of PJI at 15 years was 1% in normal weight, 2% in class III obesity, and 4% in class IV obesity. Patients who had class III and IV obesity had a 3-times and 9-times higher relative risk of PJI, respectively (P = .03, P < .001). Among patients who had ≥ 2 PJI risk factors, the absolute risk of PJI at 15 years was 2% in normal weight, 4% in class III obesity, and 18% in class IV obesity.

CONCLUSIONS

Healthy patients who had class III and IV obesity had a 3-times and 9-times increased risk of PJI at 15 years relative to normal weight patients. However, the absolute risk of PJI at 15 years was 2 and 4%, respectively. Given emerging data questioning whether BMI modification decreases PJI risk, surgeons and patients must consider both a 3-times to 9-times increased relative risk of PJI and a 2 to 4% absolute risk of PJI at 15 years for healthy patients who had a BMI ≥ 40.

LEVEL OF EVIDENCE

IV.

Multiplex cytokine analysis for the identification of novel potential synovial fluid biomarkers for periprosthetic joint infections

INTRODUCTION

Periprosthetic joint infections (PJIs) are a devastating complication of total hip (THA) and knee (TKA) arthroplasty. The use of novel techniques like multiplex cytokine analysis could contribute immensely to the identification of potential novel biomarkers.

PATIENTS AND METHODS

This is a single-centre study of patients that were treated with revision TKA, THA or hemiarthroplasty. Serum's white blood cells (WBCs), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) and synovial fluid's WBCs, percentage of polymorphonuclear neutrophils (%PMNs) and CRP were measured. Proteomic analysis targeting the secreted cytokines in synovial fluid was conducted using a 73-plex assay panel. The results were statistically compared between the septic and aseptic cases and ROC analysis to establish the area under the curve (AUC), sensitivity and specificity of each biomarker.

RESULTS

The study included 30 patients (18 revision THA cases; 3 conversion of hemiarthroplasty to THA and 9 revision TKA cases); 14 cases were considered infected, 1 likely infected and 15 not infected. The results showed statistically significant differences (p < 0.05) between infected and not infected cases in serum's ESR, CRP and synovial fluid's%PMNs, growth-regulated oncogene alpha (GROA), interleukin-8, interleukin-5, S100-A8/calprotectin and resistin (RETN) with AUCs of 0.75, 0.72, 0.95, 0.75, 0.72, 0.95, 0.83, 0.73, 0.75, 0.81 and 0.76 respectively.

CONCLUSIONS

In the present study, serum ESR and CRP as well as synovial %PMNs, GROA, IL-8, IL-5, calprotectin and RETN protein levels were identified as potential biomarkers. Further studies are needed to further investigate their diagnostic utility and optimal cut-off values.

The Utility of the Social Vulnerability Index as a Proxy for Social Disparities Following Total Knee Arthroplasty

BACKGROUND

In 2021, alternative payment models accounted for 40% of traditional Medicare reimbursements. As such, we sought to examine health disparities through a standardized categorization of social disparity using the social vulnerability index (SVI). We examined (1) risk factors for SVI ≥ 0.50, (2) incidences of complications, and (3) risk factors for total complications between patients who have SVI < 0.50 and SVI ≥ 0.50 who had a total knee arthroplasty (TKA).

METHODS

Patients who underwent TKA between January 1, 2022 and December 31, 2022 were identified in the state of Maryland. A total of 4,952 patients who had complete social determinants of health data were included. Patients were divided into 2 cohorts according to SVI: < 0.50 (n = 2,431) and ≥ 0.50 (n = 2,521) based on the national mean SVI of 0.50. The SVI identifies communities that may need support caused by external stresses on human health based on 4 themed scores: socioeconomic status, household composition and disability, minority status and language, and housing and transportation. The SVI theme of household composition and disability encompassed patients aged 65 years and more, patients aged 17 years and less, civilians who have a disability, single-parent households, and English language deficiencies. The higher the SVI, the more social vulnerability or resources are needed to thrive in a geographic area.

RESULTS

When controlling for risk factors and patient comorbidities, the theme of household composition and disability (odds ratio 2.0, 95% confidence interval 1.1 to 5.0, P = .03) was the only independent risk factor for total complications. Patients who had an SVI ≥0.50 were more likely to be women (65.8% versus 61.0%, P < .001), Black (34.4% versus 12.9%, P < .001), and have a median household income < $87,999 (21.3% versus 10.2%, P < .001) in comparison to the patients who had an SVI < 0.50, respectively.

CONCLUSIONS

The SVI theme of household composition and disability, encompassing patients aged 65 years and more, patients aged 17 years and less, civilians who have a disability, single-parent households, and English language deficiencies, were independent risk factors for total complications following TKA. Together, these findings offer opportunities for interventions with selected patients to address social disparities.

Similar Efficacy and Lower Cost Associated With Ceftazidime Compared to Tobramycin Coupled With Vancomycin in Antibiotic Spacers in the Treatment of Periprosthetic Joint Infection

BACKGROUND

Vancomycin and tobramycin have traditionally been used in antibiotic spacers. In 2020, our institution replaced tobramycin with ceftazidime. We hypothesized that the use of ceftazidime/vancomycin (CV) in antibiotic spacers would not lead to an increase in treatment failure compared to tobramycin/vancomycin (TV).

METHODS

From 2014 to 2022, we identified 243 patients who underwent a stage I revision for periprosthetic joint infection. The primary outcome was a recurrent infection requiring antibiotic spacer exchange. We were adequately powered to detect a 10% difference in recurrent infection. Patients who had a prior failed stage I or two-stage revision for infection, acute kidney injury prior to surgery, or end-stage renal disease were excluded. Given no other changes to our spacer constructs, we estimated cost differences attributable to the antibiotic change. Chi-square and t-tests were used to compare the two groups. Multivariable logistic regressions were utilized for the outcomes.

RESULTS

The combination of TV was used in 127 patients; CV was used in 116 patients. Within one year of stage I, 9.8% of the TV group had a recurrence of infection versus 7.8% of the CV group (P = .60). By final follow-up, results were similar (12.6 versus 8.6%, respectively, P = .32). Adjusting for potential risk factors did not alter the results. Cost savings for ceftazidime versus tobramycin are estimated to be $68,550 per one hundred patients treated.

CONCLUSIONS

Replacing tobramycin with ceftazidime in antibiotic spacers yielded similar periprosthetic joint infection eradication success at a lower cost. While larger studies are warranted to confirm these efficacy and cost-saving results, our data justifies the continued investigation and use of ceftazidime as an alternative to tobramycin in antibiotic spacers.

Neighborhood socioeconomic disadvantages associated with increased rates of revisions, readmissions, and complications after total joint arthroplasty

INTRODUCTION

Low socioeconomic status based on neighborhood of residence has been suggested to be associated with poor outcomes after total joint arthroplasty (TJA). The area deprivation index (ADI) is a scale that ranks (zero to 100) neighborhoods by increasing socioeconomic disadvantage and accounts for median income, housing type, and family structure. We sought to examine the potential differences between high (national median ADI = 47) and low ADI among TJA recipients at a single institution. Specifically, we assessed: (1) 30-day emergency department visits/readmissions; (2) 90-day and 1-year revisions; as well as (3) medical and surgical complications.

METHODS

A consecutive series of primary TJAs from September 21, 2015, through December 29, 2021, at a tertiary healthcare system were reviewed. A total of 3,024 patients who had complete ADI data were included. Patients were divided into groups below the national median ADI of 47 (n = 1,896) and above (n = 1,128). Multivariable regressions to determine independent risk factors accounting for ADI, race, age, sex, American Society of Anesthesiologists Classification grade, body mass index, diabetes, congestive heart failure (CHF), chronic obstructive pulmonary disease, hypertension, chronic kidney disease, alcohol abuse, substance abuse, and tobacco use. The primary outcomes of interest include evaluation of the independent association of ADI with total postoperative complications (at 30 days, 90 days, and 1 year) after adjusting for multiple relevant cofactors.

RESULTS

After adjusting for multiple relevant cofactors, at 90 days, ADI > 47 (OR, 1.36, 95% CI 1.00-1.83, P = 0.04), men versus women (OR, 0.73, 95% CI 0.54-0.99, P = 0.039), and CHF (OR, 1.90, 95% CI 1.18-3.06, P = 0.009) were independently associated with increased total complications. The ADI was not associated with increased total complications at 30 days or 1-year (All P > 0.05).

CONCLUSION

Our findings of higher complications of the ADI > 47 cohort at 90 days, reaffirm the complex relationship between ADI, patient demographics, and additional socioeconomic parameters that may influence postoperative outcomes and complications after TJA. This study utilizing ADI demonstrates potential areas of intervention and further investigation for assessing arthroplasty outcomes.

Higher Onset of Periprosthetic Joint Infections in Patients With Teeth Compared to Those Without Teeth

INTRODUCTION

Bacteria can enter the bloodstream through simple actions such as brushing teeth, flossing, and even chewing food, increasing the chance of hematogenous seeding of prosthetic joints. Antibiotics before dental work in patients with orthopedic hardware is a topic of debate because of concerns for antibiotic resistance. Patients with dentures theoretically avoid this risk due to the lack of teeth and their maintenance. Most periprosthetic joint infections (PJIs) that occur in the first six months after surgery are due to wound infection, whereas late PJIs are more commonly caused by hematogenous seeding.

MATERIALS AND METHODS

Charts from patients who received primary total joint arthroplasty were interrogated for the condition of their teeth at the time of operation. If the patient had a PJI, the time from surgery and the organism responsible were noted. Multivariate linear regressions were performed for statistical analysis to compare rates of dental status, infection, comorbidities, and demographics.

RESULTS

From the 1,500 charts reviewed, patients with teeth and edentulous had similar rates of comorbidities. PJI patients had higher rates of chronic kidney disease than patients who did not have the infection. The overall rate of infections in patients with teeth was 2.14%, close to the national average. The rate of infection in patients without teeth was 0.78%. Patients with teeth have a higher rate of infection one month or longer from surgery than edentulous patients.

CONCLUSIONS

There was an increased infection rate in patients with teeth at six months and greater since the primary total joint arthroplasty. The organisms responsible for many of the PJIs are commonly found in the mouth of humans. Having teeth is a potential risk factor for late PJI.

Update on Focal Infection Management: A Czech Interdisciplinary Consensus

BACKGROUND

The focal infection theory has been used to explain several chronic systemic diseases in the past. Systemic diseases were thought to be caused by focal infections, such as caries and periodontal diseases, and dentists were held responsible for these diseases due to the spread of oral infections. As knowledge of the interrelationship between oral microorganisms and the host immune response has evolved over the last few decades, the focal infection theory has been modified in various ways. The relationship between oral and systemic health appears to be more complex than that suggested by the classical theory of focal infections. Indeed, the contribution of the oral microbiota to some systemic diseases is gaining acceptance, as there are strong associations between periodontal disease and atherosclerotic vascular disease, diabetes, and hospital-associated pneumonia, amongst others. As many jurisdictions have various protocols for managing this oral-systemic axis of disease, we sought to provide a consensus on this notion with the help of a multidisciplinary team from the Czech Republic.

METHODS

A multidisciplinary team comprising physicians/surgeons in the specialities of dentistry, ear-nose and throat (ENT), cardiology, orthopaedics, oncology, and diabetology were quetioned with regard to their conceptual understanding of the focal infection theory particularly in relation to the oral-systemic axis. The team also established a protocol to determine the strength of these associations and to plan the therapeutic steps needed to treat focal odontogenic infections whenever possible.

RESULTS

Scoring algorithms were devised for odontogenic inflammatory diseases and systemic risks, and standardised procedures were developed for general use.

CONCLUSIONS

The designed algorithm of the oral-systemic axis will be helpful for all health care workers in guiding their patient management protocol.

Delayed Diagnosis of Mycobacteriumbovisbacillus Calmette-Guérin Periprosthetic Joint Infection Following Total Knee Arthroplasty

Periprosthetic joint infection (PJI) can present challenges in diagnosis and treatment, particularly in the setting of atypical causative organisms such as fungi and mycobacteria. Herein, we present a case and provide a review of the diagnosis and treatment of an unusual PJI caused by bacillus Calmette-Guérin, administered during the treatment of bladder cancer 3 years prior to total knee arthroplasty and subsequent PJI. Although the patient's history of bladder cancer was known, neither his Bacillus Calmette-Guérin treatment nor its potential for distant site spread that could lead to PJI were appreciated, leading to a prolonged diagnostic evaluation and treatment course.

Outcomes After Pseudomonas Prosthetic Joint Infections

BACKGROUND

Pseudomonas species are a less common but devastating pathogen family in prosthetic joint infections (PJIs). Despite advancements in management, Pseudomonas PJIs remain particularly difficult to treat because of limited antibiotic options and robust biofilm formation. This study aimed to evaluate Pseudomonas PJI outcomes at a single institution and review outcomes reported in the current literature.

METHODS

All hip or knee PJIs at a single institution with positive Pseudomonas culture were evaluated. Forty-two patients (24 hips, 18 knees) meeting inclusion criteria were identified. The primary outcome of interest was infection clearance at 1 year after surgical treatment, defined as reassuring aspirate without ongoing antibiotic treatment. Monomicrobial and polymicrobial infections were analyzed separately. A focused literature review of infection clearance after Pseudomonas PJIs was performed.

RESULTS

One-year infection clearance was 58% (n = 11/19) for monomicrobial PJIs and 35% (n = 8/23) for polymicrobial PJIs. Among monomicrobial infections, the treatment success was 63% for patients treated with DAIR and 55% for patients treated with two-stage exchange. Monotherapy with an oral or intravenous antipseudomonal agent (minimum 6 weeks) displayed the lowest 1-year clearance of 50% (n = 6/12). Resistance to antipseudomonal agents was present in 16% (n = 3/19), and two of eight patients with monomicrobial and polymicrobial PJIs developed resistance to antipseudomonal therapy in a subsequent Pseudomonas PJI. Polymicrobial infections (55%) were more common with a mortality rate of 44% (n = 10/23) at a median follow-up of 3.6 years.

CONCLUSION

Pseudomonas infections often present as polymicrobial PJIs but are difficult to eradicate in either polymicrobial or monomicrobial setting. A review of the current literature on Pseudomonas PJI reveals favorable infection clearance rates (63 to 80%) after DAIR while infection clearance rates (33 to 83%) vary widely after two-stage revision.

Diagnostic value of procalcitonin in patients with periprosthetic joint infection: a diagnostic meta-analysis

Background

The success rate of periprosthetic joint infection (PJI) treatment is still low. Early diagnosis is the key to successful treatment. Therefore, it is necessary to find a biomarker with high sensitivity and specificity. The diagnostic value of serum procalcitonin (PCT) for PJI was systematically evaluated to provide the theoretical basis for clinical diagnosis and treatment in this study.

Methods

We searched the Web of Science, Embase, Cochrane Library, and PubMed for studies that evaluated the diagnostic value of serum PCT for PJI (from the inception of each database until September 2020). Two authors independently screened the literature according to the inclusion and exclusion criteria. The quality of each selected literature was evaluated by using the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2) tool. RevMan 5.3 software was used for the quality evaluation. The sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were merged by using Meta-DiSc 1.4 software. The area under the curve (AUC) and Q index were calculated after the summary receiver operating characteristic (SROC) was generated. We also performed subgroup analysis.

Results

A total of 621 patients were enrolled in the nine studies. The pooled sensitivity of serum PCT for PJI diagnosis was 0.441 [95% confidence interval (CI), 0.384-0.500], the pooled specificity was 0.852 (95% CI, 0.811-0.888), the pooled PLR was 2.271 (95% CI, 1.808-2.853), the pooled NLR was 0.713 (95% CI, 0.646-0.786), and the pooled DOR was 5.756 (95% CI, 3.673-9.026). The area under SROC (the pooled AUC) was 0.76 (0.72-0.79). Q index was 0.6948.

Conclusion

This study showed that PCT detection of PJI had poor diagnostic accuracy. Hence, the serum PCT is not suitable as a serum marker for PJI diagnosis.

The Utility of the Area Deprivation Index in Assessing Complications After Total Joint Arthroplasty

Background

Vulnerable populations, including patients from a lower socioeconomic status, are at an increased risk for infection, revision surgery, mortality, and complications after total joint arthroplasty (TJA). An effective metric to quantify and compare these populations has not yet been established in the literature. The Area Deprivation Index (ADI) provides a composite area-based indicator of socioeconomic disadvantage consisting of 17 U.S. Census indicators, based on education, employment, housing quality, and poverty. We assessed patient risk factor profiles and performed multivariable regressions of total complications at 30 days, 90 days, and 1 year.

Methods

A prospectively collected database of 3,024 patients who underwent primary elective total knee arthroplasty or total hip arthroplasty performed by 3 fellowship-trained orthopaedic surgeons from January 1, 2015, through December 31, 2021, at a tertiary health-care center was analyzed. Patients were divided into quintiles (ADI ≤20 [n = 555], ADI 21 to 40 [n = 1,001], ADI 41 to 60 [n = 694], ADI 61 to 80 [n = 396], and ADI 81 to 100 [n = 378]) and into groups based on the national median ADI, ≤47 (n = 1,896) and >47 (n = 1,128).

Results

Higher quintiles had significantly more females (p = 0.002) and higher incidences of diabetes (p < 0.001), congestive heart failure (p < 0.001), chronic obstructive pulmonary disease (p < 0.001), hypertension (p < 0.001), substance abuse (p < 0.001), and tobacco use (p < 0.001). When accounting for several confounding variables, all ADI quintiles were not associated with increased total complications at 30 days, but age (p = 0.023), female sex (p = 0.019), congestive heart failure (p = 0.032), chronic obstructive pulmonary disease (p = 0.001), hypertension (p = 0.003), and chronic kidney disease (p = 0.010) were associated. At 90 days, ADI > 47 (p = 0.040), female sex (p = 0.035), and congestive heart failure (p = 0.001) were associated with increased total complications.

Conclusions

Balancing intrinsic factors, such as patient demographic characteristics, and extrinsic factors, such as social determinants of health, may minimize postoperative complications following TJA. The ADI is one tool that can account for several extrinsic factors, and can thus serve as a starting point to improving patient education and management in the setting of TJA.

Level of Evidence

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Extracellular Proteins Isolated from L. acidophilus as an Osteomicrobiological Therapeutic Agent to Reduce Pathogenic Biofilm Formation, Regulate Chronic Inflammation, and Augment Bone Formation In Vitro

Periprosthetic joint infection (PJI) is a challenging complication that can occur following joint replacement surgery. Efficacious strategies to prevent and treat PJI and its recurrence remain elusive. Commensal bacteria within the gut convey beneficial effects through a defense strategy named "colonization resistance" thereby preventing pathogenic infection along the intestinal surface. This blueprint may be applicable to PJI. The aim is to investigate Lactobacillus acidophilus spp. and their isolated extracellular-derived proteins (LaEPs) on PJI-relevant Staphylococcus aureus, methicillin-resistant S. aureus, and Escherichia coli planktonic growth and biofilm formation in vitro. The effect of LaEPs on cultured macrophages and osteogenic, and adipogenic human bone marrow-derived mesenchymal stem cell differentiation is analyzed. Data show electrostatically-induced probiotic-pathogen species co-aggregation and pathogenic growth inhibition together with LaEP-induced biofilm prevention. LaEPs prime macrophages for enhanced microbial phagocytosis via cathepsin K, reduce lipopolysaccharide-induced DNA damage and receptor activator nuclear factor-kappa B ligand expression, and promote a reparative M2 macrophage morphology under chronic inflammatory conditions. LaEPs also significantly augment bone deposition while abating adipogenesis thus holding promise as a potential multimodal therapeutic strategy. Proteomic analyses highlight high abundance of lysyl endopeptidase, and urocanate reductase. Further, in vivo analyses are warranted to elucidate their role in the prevention and treatment of PJIs.

The Impact of Preoperative Weight Loss Timing on Surgical Outcomes in Total Hip Arthroplasty

BACKGROUND

Elevated body mass index (BMI) increases surgical complications post-total hip arthroplasty (THA). However, the effects of rapid weight loss pre-THA remain unclear. This study evaluated patients who had initial BMIs between 40 and 50, and then achieved a BMI under 35 at various intervals before their THA. Comparisons were made with consistent obese and nonobese groups to understand potential complications.

METHODS

Using a national database, we categorized THA patients based on initial BMI and weight loss timing before the surgery. These were contrasted with those maintaining a steady BMI of 20 to 30 or 40 to 50. We monitored outcomes like periprosthetic joint infections (PJI), surgical site infections (SSI), and noninfectious revisions for 2 years postsurgery, incorporating demographic considerations. Statistical analyses utilized Chi-square tests for categorical outcomes and Student's t-tests for continuous variables.

RESULTS

Among patients who had a BMI of 45 to 50, weight loss 3 to 9 months presurgery increased PJI risks at 90 days (Odds Ratios [OR]: 2.15 to 5.22, P < .001). However, weight loss a year before the surgery lowered the PJI risk (OR: 0.14 to 0.27, P < .005). Constantly obese patients faced heightened PJI risks 1 to 2 years postsurgery (OR: 1.64 to 1.95, P < .015). Regarding SSI, risks increased with weight loss 3 to 9 months before surgery, but decreased when weight loss occurred a year earlier. In the BMI 40 to 45 group, weight loss 3 to 6 months presurgery showed higher PJI and SSI at 90 days (P < .001), with obese participants consistently at greater risk.

CONCLUSIONS

While high BMI poses THA risks, weight loss timing plays a crucial role in postoperative complications. Weight loss closer to the surgery (0 to 9 months) can heighten risks, but shedding weight a year in advance seems beneficial. Conversely, initiating weight loss approximately a year before surgery offers potential protective effects against postoperative issues. This highlights the importance of strategic weight management guidance for patients considering THA, ensuring optimal surgical results and reducing potential adverse outcomes.

Preparation and characterizations of antibacterial iodine-containing coatings on pure Ti

Iodine-containing coatings were prepared on pure Ti surfaces via electrochemical deposition to enhance their antibacterial properties. The factors influencing iodine content were analyzed using an orthogonal experiment. The electrochemically deposited samples were characterized using scanning electron microscopy with energy dispersive spectroscopy and X-ray photoelectron spectroscopy, and their antibacterial properties and cytotoxicity were evaluated. The results showed that changing the deposition time is an effective way to control the iodine content. The iodine content, coating thickness, and adhesion of the samples increased with deposition time. Iodine in the coatings mainly exists in three forms, which are I2, I3-, and pentavalent iodine. For samples with iodine-containing coatings, the antibacterial ratios against E. coli and S. aureus were greater than 90% and increased with increasing iodine content. Although the samples with iodine-containing coatings showed some inhibition of the proliferation of MC3T3-E1 cells, the cell viabilities were all higher than 80%, suggesting that iodine-containing coatings are biosafe.

The Impact of Obesity on Total Hip Arthroplasty Outcomes When Performed by High-Volume Surgeons-A Propensity Matched Analysis From a High-Volume Urban Center

BACKGROUND

Previous data suggest that obesity does not impact surgical outcomes following total knee arthroplasty performed by high-volume (HV) surgeons. However, this effect has yet to be studied in total hip arthroplasty (THA) patients. This study aimed to evaluate the impact of patient obesity on THA outcomes when surgery is performed by HV surgeons.

METHODS

A retrospective analysis of patients who underwent primary, elective THA between January 2012 and December 2022 with a HV surgeon (top 25% of surgeons by number of annual primary THA) was performed. Patients were stratified by their body mass index (BMI) into 3 cohorts: BMI ≥ 40 (morbidly obese [MO]), 30 ≤ BMI < 40 (obese), and BMI < 30 (nonobese); and 1:1:1 propensity matched based on baseline characteristics. A total of 13,223 patients were evaluated, of which 669 patients were included in the final matched analysis (223 patients per group). The average number of annual THAs performed for HV surgeons was 171 cases.

RESULTS

The MO patients had significantly longer surgical times (P < .001) and hospital lengths of stay (P < .001). Rates of 90-day readmissions (P = .211) and all-cause, septic, and aseptic revisions at the latest follow-up (P = .268, P = .903, and P = .168, respectively) were comparable between groups. In a subanalysis for non-HV surgeons, MO patients had a significantly greater risk of revision (P = .021) and trended toward significantly greater readmissions (P = .056).

CONCLUSIONS

Clinical outcomes and complication rates after THA performed by a HV surgeon are similar regardless of patient obesity status. Patients who have MO may experience improved outcomes and reduced procedural risks if they are referred to HV surgeons.

LEVEL OF EVIDENCE

III.

Non-biofilm-forming Staphylococcus epidermidis planktonic cell supernatant induces alterations in osteoblast biological function

Staphylococcal biofilms significantly contribute to prosthetic joint infection (PJI). However, 40% of S. epidermidis PJI isolates do not produce biofilms, which does not explain the role of biofilms in these cases. We studied whether the supernatant from planktonic S. epidermidis alters osteoblast function. Non-biofilm-forming S. epidermidis supernatants (PJI- clinical isolate, healthy skin isolate (HS), and ATCC12228 reference strain) and biofilm-forming supernatants (PJI+ clinical isolate, ATCC35984 reference strain, and Staphylococcus aureus USA300 reference strain) were included. Osteoblasts stimulated with supernatants from non-biofilm-forming isolates for 3, 7, and 14 days showed significantly reduced cellular DNA content compared with unstimulated osteoblasts, and apoptosis was induced in these osteoblasts. Similar results were obtained for biofilm-forming isolates, but with a greater reduction in DNA content and higher apoptosis. Alkaline phosphatase activity and mineralization were significantly reduced in osteoblasts treated with supernatants from non-biofilm-forming isolates compared to the control at the same time points. However, the supernatants from biofilm-forming isolates had a greater effect than those from non-biofilm-forming isolates. A significant decrease in the expression of ATF4, RUNX2, ALP, SPARC, and BGLAP, and a significant increase in RANK-L expression were observed in osteoblasts treated with both supernatants. These results demonstrate that the supernatants of the S. epidermidis isolate from the PJI- and HS (commensal) with a non-biofilm-forming phenotype alter the function of osteoblasts (apoptosis induction, failure of cell differentiation, activation of osteoblasts, and induction of bone resorption), similar to biofilm-forming isolates (PJI+, ATCC35984, and S. aureus USA300), suggesting that biofilm status contributes to impaired osteoblast function and that the planktonic state can do so independently of biofilm production.

Using Three-Dimensional Printing Technology to Solve Complex Primary Total Hip Arthroplasty Cases: Do We Really Need Custom-Made Guides and Templates? A Critical Systematic Review on the Available Evidence

The burden of osteoarthritis (OA) is around 300 million people affected worldwide, with the hip representing a commonly affected joint. Total hip arthroplasty (THA) has been used with notable success as a definitive treatment to improve pain and function in hip OA patients. The recent advent of new technologies, such as 3D printing, has pushed the application of these new concepts toward applications for the well-known THA. Currently, the evidence on the use of 3D printing to aid complex primary THA cases is still scarce.

METHODS

An extensive literature review was conducted to retrieve all articles centered on the use of 3D printing in the setting of primary THA.

RESULTS

A total of seven studies were included in the present systematic review. Four studies investigated the use of 3D-printed surgical guides to be used during surgery. The remaining three studies investigated the benefit of the use of 3D-printed templates of the pelvis to simulate the surgery.

CONCLUSIONS

The use of 3D printing could be a promising aid to solve difficult primary total hip arthroplasty cases. However, the general enthusiasm in the field is not supported by high-quality studies, hence preventing us from currently recommending its application in everyday practice.

The utilization of US-based large data in arthroplasty research: Bibiliometric analysis of trends and hotspots

Background

The accessibility of digital information has expanded orthopaedic surgery with expanded role of Big Databases. The increasing interest have led to creation of large databases with increasing utilization in retrospective studies. The aim of this study is to identify Big Database research and predict future hotspots.

Methods

Big Database publications between 1982 and 2022 were identified from the Web of Science Core Collection of Clarivate Analytics. Bibliometric indicators were obtained and imported for further analysis with VOSviewer and Bibliometrix to identify previous and ongoing trends within this field.

Results

Bibliometric sourcing identified 811 total articles that was associated with major databases. Twenty-eight countries published manuscript in the field with the United States as the largest contributor. The most relevant institutions were Cleveland Clinic and Harvard University. Mont MA was the most productive and influential author. Co-occurrence visualization and thematic map identified niche and major themes within the literature.

Conclusions

Large Database research continue to show an increasing trend since 2011 with contributions globally. United States institutions and authors are the leading contributors in big database research. This study identifies previous, current, and developing trends within this field for future hotspot development.

Outcomes of Enterobacter cloacae-Associated Periprosthetic Joint Infection Following Hip Arthroplasties

Background

Periprosthetic joint infections (PJIs) represent a serious complication following total hip arthroplasty (THA) and are associated with significant morbidity. While recent data suggest that Enterobacter cloacae is an emerging source of PJI, characteristics and outcomes of E. cloacae-associated infections are rarely described. The study aimed to present and describe the findings and outcomes of E. cloacae-associated PJI in our department.

Methods

This is a retrospective descriptive study of patients who underwent revision THA for E. cloacae-associated PJI between 2011 and 2020 and has a minimum follow-up of 2 years. Outcomes included organism characteristics as well as clinical outcomes, represented by the number of reoperations needed for PJI eradication and the Musculoskeletal Infection Society (MSIS) outcome reporting tool score. Of 108 revision THAs, 12 patients (11.1%) were diagnosed with E. cloacae-associated PJI.

Results

The majority of cases had a polymicrobial PJI (n=8, 66.7%). Five E. cloacae strains (41.7%) were gentamicin-resistant. Six patients (50.0%) underwent 2 or more revisions, while 3 of them (25.0%) required 4 or more revisions until their PJI was resolved. When utilizing the MSIS outcome score, the first surgical intervention was considered successful (MSIS score tiers 1 and 2) for 5 patients (41.7%) and failed (tiers 3 and 4) for 7 patients (58.3%).

Conclusions

E. cloacae is emerging as a common source of PJI following hip arthroplasty procedures. The findings of our study suggest that this pathogen is primarily of polymicrobial nature and represents high virulence and poor postoperative outcomes, as represented by both an increased number of required revision procedures and high rates of patients with MSIS outcome scores of 3 and 4. When managing patients with E. cloacae-associated PJI, surgeons should consider these characteristics and inform patients regarding predicted outcomes.

Development of droplet digital PCR-based detection of bacterial pathogens in prosthetic joint infection: a preliminary study using a synthesized model plasmid

Periprosthetic joint infection (PJI) can be diagnosed to characterize the microorganisms constituting a biofilm, which is an essential procedure for proper treatment. The gold standard method for detecting and identifying the causative microorganism is culture of microorganisms from patients-derived sample.; however, this method takes a long time and has low sensitivity. To compensate for these limitations, identification methods based on real-time PCR (RT-PCR) have been widely used. However, RT-PCR also has limitations, including low sensitivity and the requirement of a standard curve for quantification. Therefore, to prevent significant proliferation of pathogenic bacteria, it is important to detect a limited number of infectious bacteria during early stages of PJI. In the present study, we developed droplet digital PCR-based detection of bacterial pathogens in PJI. And we evaluated the analytical performance of the assay using a model plasmid, based on the 16S ribosomal DNA sequence of target bacteria commonly found in PJI. We also prepared genomic DNA extracted from E. coli, S. aureus, and S. epidermidis to test whether ddPCR provides better sensitivity and quantification of the target sequences. ddPCR detected 400 attograms of target DNA, which was more than 10 times less than that detected by real-time PCR using synthesized plasmid. In addition, ddPCR detected target regions from genomic DNA of 50 femtograms for E. coli, 70 femtograms for S. epidermidis, and 90 femtograms for S. aureus. The results indicate that ddPCR has the potential to decrease the microbial detection limit and provide precise detection, signifying its effectiveness for early PJI.

Tranexamic acid administration for the prevention of periprosthetic joint infection and surgical site infection: a systematic review and meta-analysis

INTRODUCTION

Tranexamic acid (TXA) has been widely utilized to reduce blood loss and allogeneic transfusions in patients who undergo lower limb arthroplasty. In recent years, there have been several articles reporting the incidence of periprosthetic joint infection (PJI) as a primary outcome of TXA administration, but no meta-analysis has been conducted to date. The present systematic review and meta-analysis evaluated the efficacy of TXA administration in preventing PJI and surgical site infection (SSI).

MATERIALS AND METHODS

Pubmed, CINAHL, and the Cochrane Library bibliographic databases were searched for studies published by May 24, 2022, that evaluated the effects of TXA on PJI and SSI. Two researchers screened the identified studies based on the PRISMA flow diagram. The quality of each randomized clinical trial was assessed using Version 2 of the Cochrane risk-of-bias tool for randomized trials (ROB2.0), and the quality of cohort and case-control studies was assessed by risk of bias for nonrandomized studies (ROBANS-I).

RESULTS

Of the 2259 articles identified from the database search, 31 were screened and selected. Treatment with TXA significantly reduced the incidence of overall infection, including PJI, SSI, and other infections (OR 0.55; 95% CI 0.49-0.62) (P < 0.00001), and that of PJI alone (OR 0.53; 95% CI 0.47-0.59) (P < 0.00001). TXA reduced the incidence of overall infection in patients who underwent total hip arthroplasty (THA; OR 0.51; 95% CI: 0.35-0.75) (P = 0.0005) and total knee arthroplasty (TKA; OR 0.55; 95% CI: 0.43-0.71) (P < 0.00001). Intravenous administration of TXA reduced the incidence of overall infection (OR 0.59; 95% CI 0.47-0.75) (P < 0.0001), whereas topical administration did not.

CONCLUSIONS

Intravenous administration of TXA reduces the incidence of overall infection in patients undergoing both THA and TKA.

LEVEL OF EVIDENCE

Level III.

Race Associated With Increased Complication Rates After Total Knee Arthroplasty

BACKGROUND

Racial and ethnic disparities have been suggested to be associated with poor outcomes after total knee arthroplasty (TKA). While socioeconomic disadvantage has been studied, analyses of race as the primary variable are lacking. Therefore, we examined the potential differences between Black and White TKA recipients. Specifically, we assessed 30-day and 90-day, as well as 1 year: (1) emergency department visits and readmissions; (2) total complications; (3) as well as risk factors for total complications.

METHODS

A consecutive series of 1,641 primary TKAs from January 2015 to December 2021 at a tertiary health care system were reviewed. Patients were stratified according to race, Black (n = 1,003) and White (n = 638). Outcomes of interest were analyzed using bivariate Chi-square and multivariate regressions. Demographic variables such as sex, American Society of Anesthesiologists classification, diabetes, congestive heart failure, chronic pulmonary disease, and socioeconomic status based on Area Deprivation Index were controlled for across all patients.

RESULTS

The unadjusted analyses found that Black patients had an increased likelihood of 30-day emergency department visits and readmissions (P < .001). However, in the adjusted analyses, Black race was demonstrated to be a risk factor for increased total complications at all-time points (P ≤ .0279). Area Deprivation Index was not a risk for cumulative complications at these time points (P ≥ .2455).

CONCLUSION

Black patients undergoing TKA may be at increased risk for complications with more risk factors including higher body mass index, tobacco use, substance abuse, chronic obstructive pulmonary disease, congestive heart failure, hypertension, chronic kidney disease, and diabetes and were thus, "sicker" initially than the White cohort. Surgeons are often treating these patients at the later stages of their diseases when risk factors are less modifiable, which necessitates a shift to early, preventable public health measures. While higher socioeconomic disadvantage has been associated with higher rates of complications, the results of this study suggest that race may play a greater role than previously thought.

ACR Appropriateness Criteria® Imaging After Total Hip Arthroplasty

This article reviews evidence for performing various imaging studies in patients with total hip prostheses. Routine follow-up is generally performed with radiography. Radiographs are also usually the initial imaging modality for patients with symptoms related to the prosthesis. Following acute injury with pain, noncontrast CT may add information to radiographic examination regarding the presence and location of a fracture, component stability, and bone stock. Image-guided joint aspiration, noncontrast MRI, and white blood cell scan and sulfur colloid scan of the hip, are usually appropriate studies for patients suspected of having periprosthetic infection. For evaluation of component loosening, wear, and/or osteolysis, noncontrast CT or MRI are usually appropriate studies. Noncontrast MRI is usually appropriate for identifying adverse reaction to metal debris related to metal-on-metal articulations. For assessing patients after hip arthroplasty, who have trochanteric pain and nondiagnostic radiographs, ultrasound, or MRI are usually appropriate studies. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Rank-Ordered List of Cost-effective Strategies for Preventing Prosthetic Joint Infection in Total Joint Arthroplasty in an Academic US Hospital

Although the overall rate of prosthetic joint infection (PJI) is low, it remains a major complication associated with total joint arthroplasty (TJA). PJI represents a significant economic burden to the health care system that is projected to increase commensurate with increasing joint replacement volumes. This review provides a rank-ordered list of cost-effective strategies that are performable intraoperatively and have data supporting their efficacy at preventing PJI after TJA. This study may be helpful in assisting surgeons, ambulatory surgery center owners, and hospital acquisition committees to make reasonable and cost-conscious decisions in the face of changing reimbursement. [Orthopedics. 2023;46(6):327-332.].

Design Characteristics and Recruitment Rates for Randomized Trials of Peri-Prosthetic Joint Infection Management: A Systematic Review

Prosthetic joint infections (PJI) present a major management challenge for practicing orthopedic surgeons and infectious disease physicians. There are few high-quality data to inform treatment guidelines. The aim of this systematic review was to report the design characteristics and recruitment rates for randomized controlled trials (RCTs) of PJI management. Trials were considered eligible for inclusion if human participants were randomized to any management intervention for PJI. We searched Medline, PubMed, Embase, Web of Science, Cochrane Database, ANZ Clinical Trials Registry, ClinicalTrials.gov, and the EU Clinical Trials Register until the end of May 2023. The systematic review was registered with PROSPERO (CRD42018112646). We identified 15 published RCTs with a total of 1743 participants with PJI. The median (interquartile range [IQR]) number of successfully recruited participants was 63 (38-140), with 0.28 (0.13-0.96) enrolments per site per month. Only four trials (36.4%) achieved the target recruitment. All RCTs applied different primary endpoints and varying definitions of a 'good' outcome. Despite recent improvements, PJI RCTs are characterized by slow recruitment and heterogeneous endpoint assessments, which preclude synthesis in a standard meta-analytic framework. To inform international guidelines, future PJI trials should be run as multi-country trials at high-recruiting sites.

The Potential Role of Gut Bacteriome Dysbiosis as a Leading Cause of Periprosthetic Infection: A Comprehensive Literature Review

(1) Background: Periprosthetic joint infections (PJIs) represent a small yet important risk when undertaking a joint arthroplasty; they occur in approximately 1-2% of treatments. These infections create a medical and financial burden for patients and healthcare systems. Despite the introduction of recognized best clinical practices during arthroplasty operations, it is not yet possible to further reduce the risk of infection after surgery. The purpose of this review is to raise awareness of the potential role of gut dysbiosis in the development of PJIs and to highlight the potential of the gut bacteriome as a possible target for preventing them. (2) Methods: We compiled all the available data from five databases, examining the effects of gut dysbiosis in human and murine studies, following PRISMA guidelines, for a total of five reviewed studies. (3) Results: One human and one murine study found the Trojan horse theory applicable. Additionally, inflammatory bowel diseases, gut permeability, and oral antibiotic ingestion all appeared to play a role in promoting gut dysbiosis to cause PJIs, according to the other three studies. (4) Conclusions: Gut dysbiosis is linked to an increased risk of PJI.

Higher Rates of Readmission After Acute Total Hip Arthroplasty Versus Open Reduction Internal Fixation for Elderly Acetabular Fractures, a National Study From 2010 to 2019

OBJECTIVES

To evaluate the initial complications and short-term readmissions and reoperations after open reduction internal fixation (ORIF) versus acute total hip arthroplasty (THA) for elderly acetabular fractures.

DESIGN

Retrospective database review.

SETTING

All hospitalizations in the National Readmissions Database and National Inpatient Sample.

PATIENTS/PARTICIPANTS

Patients 60 years of age or older with closed acetabular fractures managed surgically identified from the National Readmissions Database or National Inpatient Sample between 2010 and 2019.

INTERVENTION

Acute THA with or without ORIF.

MAIN OUTCOME MEASUREMENTS

30-, 90-, and 180-day readmissions and reoperations and index hospitalization complications.

RESULTS

An estimated 12,538 surgically managed acetabular fractures in elderly patients occurred nationally between 2010 and 2019, with 10,008 (79.8%) undergoing ORIF and 2529 (20.2%) undergoing THA. Length of stay was 1.7 days shorter ( P < 0.001) and probability of nonhome discharge was reduced (OR 0.68, P = 0.009) for THA patients than for ORIF patients. THA was associated with lower rates of pneumonia (4.6 vs. 9.1%, P < 0.001) and other respiratory complications (10.2 vs. 17.6%) when compared with ORIF. At 30 days, THA patients had higher rates of readmission (13.9 vs. 10.1%, P = 0.007), related readmission (5.4 vs. 1.2%, P < 0.001), readmission for dislocation (3.1 vs. 0.3%, P < 0.001), and reoperations (2.9 vs. 0.9%, P = 0.002). At 180 days, THA patients had higher rates of related readmission (10.1% vs. 3.9%, P < 0.001), readmission for dislocation (5.1% vs. 1.3%, P < 0.001), and readmission for SSI (3.4 vs. 0.8%, P = 0.005).

CONCLUSIONS

Acute THA is associated with lower length of stay and certain index hospitalization complications, but higher rates of readmissions for related reasons and specifically for dislocation.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.