The use of erythromycin and colistin-loaded cement in total knee arthroplasty does not reduce the incidence of infection: a prospective randomized study in 3000 knees

Enhancing PMMA Cements With Manually Added Antimicrobial Agents

Periprosthetic joint infection (PJI) is an infrequent yet severe complication. A fundamental aspect of PJI treatment involves the use of polymethylmethacrylate (PMMA) cement augmented with antibiotics. For therapeutic application, it is often necessary to manually mix antibiotics with commercially produced PMMA cements. However, the potential issues arising from this manual admixing have not been thoroughly documented. This study aims to elucidate the impact of additional homogenization through dry mixing of a polymer-active substance blend on the quality of manually mixed PMMA cement. In this laboratory-based investigation, four cement samples were prepared using various methods for the manual incorporation and homogenization of the antibiotic vancomycin. The reference controls were Copal G + V and Copal G + C pro (Heraeus Medical GmbH, Wehrheim, Germany), representing commercially available PMMA cements and a closed mixing system. The samples were analyzed for mechanical, microbiological, and microscopic properties. The mechanical and microbiological analyses revealed no statistically significant differences between the manually mixed samples and the references. However, microscopic examination of the mixing cartridges' inner surfaces indicated scratching and signs of abrasion during the mixing process. The manual incorporation of antibiotics into PMMA cement should be limited to specific indications, with a preference for using commercially available mixtures whenever possible.

Effectiveness of Local Antibiotics for Infection Prevention in Primary Joint Arthroplasty: A Systematic Review and Meta-Analysis

Background/Objectives: To evaluate the effectiveness of local antibiotic prophylaxis (e.g., powder, bone cement, intraosseous injection) in reducing periprosthetic joint infections (PJI) and deep wound infections in adults undergoing primary joint replacement surgery. Methods: A comprehensive search of PubMed, EMBASE, and the Cochrane Library was conducted from inception to 7 September 2024, including randomized controlled trials (RCTs) and cohort studies without language restrictions. Quality assessment was performed using the Cochrane Risk of Bias (RoB) 2.0 for RCTs and the Newcastle-Ottawa Scale (NOS) for cohort studies. Infection rates were extracted and analyzed using risk ratios (RR) or odds ratios (OR) in a random-effects model with Review Manager (RevMan) 5.4. Sensitivity analysis and meta-regression were also performed to validate the study results and possible risk factors. Results: Twelve RCTs and 21 cohort studies were included in the review. Vancomycin powder in the cohort studies demonstrated statistical significance (OR = 0.47, 95% confidence interval (CI): 0.36-0.61, I2 = 0%), in contrast to the results in the RCTs (RR = 0.37, 95% CI: 0.06-2.47, I2 = 49%). Sensitivity analyses confirmed the robustness and statistical significance of these findings. Both the control and treatment groups primarily cultured Gram-positive pathogens, including in the overall data and specifically for vancomycin powder. The evidence for the use of intraosseous injection (RR of RCTs not estimable, I2 not applicable; OR of cohorts = 0.12, 95% CI: 0.02-0.63, I2 = 0%) and bone cement (RR of RCTs = 0.40, 95% CI: 0.14-1.17, I2 = 56%; OR of cohorts = 1.88, 95% CI: 1.25-2.82, I2 not applicable) was inconclusive. Smoking was identified as an important risk factor for post-operative infection. Further research, including more robust trials and cohort studies, is needed to confirm these findings. Conclusions: Local administration of vancomycin powder appears effective in preventing deep wound infection after arthroplasty.

Antibiotic-loaded bone cement is associated with a reduction of the risk of revision of total knee arthroplasty: Analysis of the Catalan Arthroplasty Register

PURPOSE

The purpose of this study was to analyse the impact on peri-prosthetic joint infection (PJI) rate and prosthetic survival using antibiotic-loaded bone cement (ALBC) versus plain cement during total knee arthroplasty (TKA).

METHODS

A retrospective cohort study was conducted. The main data source was the Catalan Arthroplasty Register (RACat). TKAs with surgery date between 1 January 2011 and 31 December 2020 were analysed and followed up until 31 December 2023. The main variable of interest was the type of cement (ALBC vs. plain cement), and several endpoints (septic revision, aseptic revision, and all-cause revision) were considered. The analysed outcomes were revision rates, survival rates and risk factors' hazard ratios (HR).

RESULTS

A total of 22,781 TKAs were analysed, 13,125 (57.6%) of them with plain cement and 9656 (42.4%) with ALBC. The septic revision rate was lower in the ALBC group after 3 months of follow-up (0.52% vs. 0.78%, p value = 0.04). Prosthetic survival with respect to the aseptic revision endpoint was also higher for the ALBC group during the whole follow-up period (~158 months). Regarding risk factors for infection, ALBC showed a protective effect, HR: 0.53 (0.44, 0.63), while sex (being male) and the analysed comorbidities increased the risk.

CONCLUSIONS

ALBC is associated with a reduction in both the septic revision and the aseptic revision rate after TKA, and thus with higher prosthetic survival.

LEVEL OF EVIDENCE

Level III, Therapeutic, retrospective.

Number of Doses of Systemic Antibiotic Prophylaxis May Be Reduced in Cemented Primary Knee Arthroplasty Irrespective of Use of Antibiotic in the Cement: A Multiregistry-Based Meta-Analysis

Background

The use of systemic antibiotic prophylaxis (SAP) and antibiotic-loaded bone cement (ALBC) is the accepted practice to reduce the risk of periprosthetic joint infection (PJI) in primary total knee arthroplasty (pTKA). However, practice varies internationally. This study's primary aim was to compare the risk of PJI revision after pTKA with ALBC + SAP vs. plain bone cement (PBC) + SAP, and the secondary aim was to assess whether the risk of PJI revision varies with the number of SAP doses.

Methods

Cohort of 289,926 pTKAs for osteoarthritis from arthroplasty registries in Denmark, New Zealand, Norway, Romania, and United States registered from 2010 to 2020. One-year revision for PJI following pTKA with ALBC + SAP vs. PBC + SAP, and single vs. multiple SAP doses was compared. We computed cumulative percent revision (1 minus Kaplan-Meier) using distributed analysis method and adjusted hazard rate ratios (HRRs) using Cox regression analyses within each registry. Advanced distributed meta-analysis was performed to summarize HRRs from all countries.

Results

Among all pTKAs, 64.4% were performed with ALBC + SAP. Each registry reported a 1-year cumulative percent revision for PJI of <1.00% for both pTKAs with ALBC + SAP (0.34%-0.80%) and with PBC + SAP (0.54%-0.69%). The distributed meta-analysis showed HRR = 1.21; (95% confidence interval [CI], 0.79-1.87) for ALBC + SAP compared with PBC + SAP. Similar risk of PJI revision was observed between pTKAs with ALBC + single vs. multiple doses of SAP: 2 doses (0.95; 95% CI, 0.68-1.33), 3 doses (1.09; 95% CI, 0.64-1.87), and 4 doses (1.23; 95% CI, 0.69-2.21). Comparable results were found for the PBC + SAP group except for higher risk of PJI revision with 4 doses of SAP (2.74; 95% CI, 1.11-6.75).

Conclusions

ALBC and PBC entailed similar risk of PJI revision when patients received SAP in pTKA, regardless of number of SAP doses. ALBC or PBC used in combination with SAP in pTKAs, with one single preoperative dose of SAP may be sufficient without compromising the patient safety.

Level of evidence

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

In Vivo Intra-Articular Antibiotic Concentrations at 24 Hours After TKA Fall Below the Minimum Inhibitory Concentration for Most Bacteria: A Randomized Study of Commercially Available Bone Cement

BACKGROUND

The use of antibiotic-loaded bone cement (ALBC) to help reduce the risk of infection after primary total knee arthroplasty (TKA) is controversial. There is a paucity of in vivo data on the elution characteristics of ALBC. We aimed to determine whether the antibiotic concentrations of 2 commercially available ALBCs met the minimum inhibitory concentration (MIC) and minimum biofilm eradication concentration (MBEC) for common infecting organisms.

METHODS

Forty-five patients undergoing TKA were randomized to receive 1 of the following: bone cement without antibiotic (the negative control; n = 5), a commercially available formulation containing 1 g of tobramycin (n = 20), or a commercially available formulation containing 0.5 g of gentamicin (n = 20). Intra-articular drains were placed, and fluid was collected at 4 and 24 hours postoperatively. An automated immunoassay measuring antibiotic concentration was performed, and the results were compared against published MIC and MBEC thresholds.

RESULTS

The ALBC treatment groups were predominantly of White (65%) or Black (32.5%) race and were 57.5% female and 42.4% male. The mean age (and standard deviation) was 72.6 ± 7.2 years in the gentamicin group and 67.6 ± 7.4 years in the tobramycin group. The mean antibiotic concentration in the tobramycin group was 55.1 ± 37.7 μg/mL at 4 hours and 19.5 ± 13.0 μg/mL at 24 hours, and the mean concentration in the gentamicin group was 38.4 ± 25.4 μg/mL at 4 hours and 17.7 ± 15.4 μg/mL at 24 hours. Time and antibiotic concentration had a negative linear correlation coefficient (r = -0.501). Most of the reference MIC levels were reached at 4 hours. However, at 24 hours, a considerable percentage of patients had concentrations below the MIC for many common pathogens, including Staphylococcus epidermidis (gentamicin: 65% to 100% of patients; tobramycin: 50% to 85%), methicillin-sensitive Staphylococcus aureus (gentamicin: 5% to 90%; tobramycin: 5% to 50%), methicillin-resistant S . aureus (gentamicin: 5% to 65%; tobramycin: 50%), Streptococcus species (gentamicin: 10% to 100%), and Cutibacterium acnes (gentamicin: 10% to 65%; tobramycin: 100%). The aforementioned ranges reflect variation in the MIC among different strains of each organism. Gentamicin concentrations reached MBEC threshold values at 4 hours only for the least virulent strains of S . aureus and Escherichia coli. Tobramycin concentrations did not reach the MBEC threshold for any of the bacteria at either time point.

CONCLUSIONS

The elution of antibiotics from commercially available ALBC decreased rapidly following TKA, and only at 4 hours postoperatively did the mean antibiotic concentrations exceed the MIC for most of the pathogens. Use of commercially available ALBC may not provide substantial antimicrobial coverage following TKA.

LEVEL OF EVIDENCE

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

A systematic review and meta-analysis of antibiotic-loaded bone cement for prevention of deep surgical site infections following primary total joint replacement

BACKGROUND

The use of antibiotic-loaded bone cement (ALBC) as a mean for preventing deep surgical site infections (SSI) after total joint replacement is controversial. Therefore, we have conducted a meta-analysis to evaluate the prophylactic effect of ALBC for SSI prevention in patients undergoing arthroplasty. This study was conducted to revise treatment guidelines for MRSA infections in Japan.

METHODS

PubMed (Medline), Scopus, Embase, Web of Science and Cochrane library were searched for relevant articles comparing preventive effect of ALBC for patients undergoing primary total joint arthroplasty by August 2022. Primary outcome was the incidence of deep SSI. Subgroup analyses by type of surgery (total hip (THA) or knee (TKA) arthroplasty) and by causative pathogen (methicillin-resistant Staphylococcus aureus (MRSA)) were performed.

RESULTS

Of the 3379 studies identified for screening, six studies involving 5745 patients were included. The use of ALBC significantly reduced the incidence of deep SSI in overall patients (risk ratio [RR] 0.60, 95% confidential interval [CI] 0.39-0.92), but the evidence level was very low. There was no significant preventive effect for ALBC compared with non-ALBC in both THA and TKA (THA, RR 0.52, 95% CI 0.23-1.16; TKA, RR 0.64, 95% CI 0.38-1.06), and for preventing MRSA-SSI (RR 0.27, 95% CI 0.03-2.41).

CONCLUSIONS

Although the overall preventive effect of ALBC was significant, the evidence level was very low. Thus, the routine use of ALBC as a mean to prevent SSI in arthroplasty may not be suggested.

The Use of Erythromycin and Colistin Cement in Total Knee Arthroplasty Does Not Reduce the Incidence of Infection: A Randomized Study in 2,893 Knees With a 9-year Average Follow-Up

BACKGROUND

One of the most severe complications of primary total knee arthroplasty (TKA) is prosthetic joint infection. Currently, the use of antibiotic-loaded cement for the prevention of infection is still controversial. The aim of the present study was to evaluate if the use of antibiotic-loaded cement reduces the infection rate in primary TKA in long-term follow-up (more than 5 years average follow-up).

METHODS

This study is the follow-up extension of a prospective randomized study, with 2,893 cemented TKA performed between 2005 and 2010 at our institution. There were 2 different cohorts depending on which bone cement was used: without antibiotics (control group) or those loaded with erythromycin and colistin (study group). All patients received the same systemic prophylactic antibiotics. The patients were followed for a minimum of twelve months. The diagnosis of prosthetic joint infection was done according to Zimmerli criteria.

RESULTS

In 1,452 patients, the prosthetic components were fixed using bone cement without antibiotics, whereas in 1,441 patients, bone cement was loaded with erythromycin and colistin. Both groups were comparable in terms of all the possible risk factors studied. We found a total of 53 deep infections, with a mean rate of 1.8%. There were no differences between the groups as to whether bone cement with or without antibiotics had been used (P = .58). The average duration of follow-up was 8.7 years. In terms of prosthetic revision due to aseptic loosening, there were no differences between groups (P = .32), with 33 revision arthroplasties in the control group and 37 in the study group. Moreover, we analyzed the erythromycin resistance rate, with no differences between both groups (P = .6).

CONCLUSIONS

The use of erythromycin and colistin-loaded bone cement in TKA did not lead to a decrease in the rate of infection in long-term follow-up, a finding that suggests that its use would not be indicated in the general population.

Effects of Vancomycin/Tobramycin-Doped Ceramic Composite (Polyvinyl Alcohol Composite-Vancomycin/Tobramycin-Polymeric Dicalcium Phosphate Dihydrate) in a Rat Femur Model Implanted With Contaminated Porous Titanium Cylinders

BACKGROUND

Periprosthetic joint infection (PJI) remains common and problematic. We hypothesized that using a bioceramic that provided rapid release of the antibiotics (vancomycin [VAN] or VAN and tobramycin [VAN and TOB]) from a polyvinyl-alcohol-composite (PVA) combined with a delayed and sustained antibiotic release from polymeric-dicalcium-phosphate-dihydrate (PDCPD) ceramic would inhibit S. aureus-associated implant infections.

METHODS

A total of 50 male Sprague Dawley rats were randomly divided into 5 groups-I: negative control; II: bacteria only; III: bacteria + saline wash; IV: bacteria + PVA-VAN-PDCPD, and V: bacteria + PVA-VAN-TOB-PDCPD. A porous titanium (Ti) implant was press-fit into the rat knee. S. aureus-containing broth was added into the joint space creating a PJI. After 1 week, the joints from groups III to V were washed with saline and the fluid collected for bacterial quantification. This was followed by saline irrigation treatment (groups III to V) and application of the antibiotic-loaded PVA-PDCPD bioceramic (groups IV and V). On day 21, joint fluid was collected, and the implants harvested for bacterial quantification.

RESULTS

No bacteria were isolated from the negative control (group I). The positive control (group II) was positive on both days 7 and 21. Bacteria were still present on day 21 in the fluid and implant in group III. Groups (IV and V) showed a decrease in the bacterial burden in the fluid and implant on day 21. There were significant differences in bacteria levels in the collected wash fluid and on the implant at day 21 between the saline wash (group III) and treatment groups (IV and V).

CONCLUSIONS

In this animal model of acute periprosthetic infection, treatment with PVA-VAN-PDCPD and PVA-VAN/TOB-PDCPD reduced bacterial load in the infected joint and the infected Ti implant. Application of PVA-VAN-PDCPD and/or PVA-VAN/TOB-PDCPD after saline irrigation could be used as an addition to the treatment of PJI.

Therapeutic Efficacy of an Erythromycin-Loaded Coaxial Nanofiber Coating in a Rat Model of S. aureus-Induced Periprosthetic Joint Infection

Implant surface nanofiber (NF) coatings represent an alternative way to prevent/treat periprosthetic joint infection (PJI) via local drug release. We developed and characterized a coaxial erythromycin (EM)-doped PLGA/PCL-PVA NF coating. The purpose of this study was to determine the efficacy of EM-NF coatings (EM0, no EM, EM100 (100 mg/mL), and EM1000 (1000 mg/mL) wt/wt) in a rat PJI model. A strong bond of the EM-NF coating to the surface of titanium (Ti) pins was confirmed by in vitro mechanical testing. Micro-computed tomography (mCT) analysis showed that both EM100 and EM1000 NF effectively reduced periprosthetic osteolysis compared to EM0 at 8 and 16 weeks after implantation. Histology showed that EM100 and EM1000 coatings effectively controlled infection and enhanced periprosthetic new bone formation. The bone implant contact (BIC) of EM100 (35.08%) was higher than negative controls and EM0 (3.43% and 0%, respectively). The bone area fraction occupancy (BAFO) of EM100 (0.63 mm2) was greater than controls and EM0 (0.390 mm2 and 0.0 mm2, respectively). The BAFO of EM100 was higher than that of EM1000 (0.3 mm2). These findings may provide a basis for a new implant surface fabrication strategy aimed at reducing the risks of defective osseointegration and PJI.

The effect of different preventive strategies during total joint arthroplasty on periprosthetic joint infection: a network meta-analysis

BACKGROUND

Periprosthetic joint infection after total joint arthroplasty has a large incidence, and it may often require two or more stages of revision, placing an additional burden on clinicians and patients. The purpose of this network meta-analysis is to evaluate the effect of four different preventive strategies during total joint arthroplasty on the prevention of periprosthetic joint infection.

METHODS

The study protocol was registered at PROSPERO (CRD: 42,023,448,868), and the literature search databases included Web of Science, PubMed, OVID Cochrane Central Register of Controlled Trials, OVID EMBASE, and OVID MEDLINE (R) ALL that met the requirements. The network meta-analysis included randomized controlled trials, retrospective cohort studies and prospective cohort studies with the outcome of periprosthetic joint infection. The gemtc R package was applied to perform the network meta-analysis to evaluate the relative results of different preventive strategies.

RESULTS

This network meta-analysis study included a total of 38 articles with 4 preventive strategies and negative controls. No improvement was observed in antibiotic-loaded bone cement compared with negative controls. Chlorhexidine showed the highest probability of delivering the best preventive effect, and povidone iodine had the second highest probability. Although vancomycin ranked after chlorhexidine and povidone iodine, it still showed a significant difference compared with negative controls. In addition, the incidence after applying chlorhexidine was significantly lower than that after applying negative controls and vancomycin. In the heterogeneity test between direct and indirect evidence, there was no apparent heterogeneity between them.

CONCLUSION

The study indicated that chlorhexidine, povidone iodine and vancomycin showed significant efficacy in preventing periprosthetic joint infection after total joint arthroplasty, while antibiotic-loaded bone cement did not. Therefore, more high-quality randomized controlled trials are needed to verify the results above.

Periprosthetic Joint Infection After Total Knee Arthroplasty With or Without Antibiotic Bone Cement

Importance

Despite increased use of antibiotic-loaded bone cement (ALBC) in joint arthroplasty over recent decades, current evidence for prophylactic use of ALBC to reduce risk of periprosthetic joint infection (PJI) is insufficient.

Objective

To compare the rate of revision attributed to PJI following primary total knee arthroplasty (TKA) using ALBC vs plain bone cement.

Design, Setting, and Participants

This international cohort study used data from 14 national or regional joint arthroplasty registries in Australia, Denmark, Finland, Germany, Italy, New Zealand, Norway, Romania, Sweden, Switzerland, the Netherlands, the UK, and the US. The study included primary TKAs for osteoarthritis registered from January 1, 2010, to December 31, 2020, and followed-up until December 31, 2021. Data analysis was performed from April to September 2023.

Exposure

Primary TKA with ALBC vs plain bone cement.

Main Outcomes and Measures

The primary outcome was risk of 1-year revision for PJI. Using a distributed data network analysis method, data were harmonized, and a cumulative revision rate was calculated (1 - Kaplan-Meier), and Cox regression analyses were performed within the 10 registries using both cement types. A meta-analysis was then performed to combine all aggregated data and evaluate the risk of 1-year revision for PJI and all causes.

Results

Among 2 168 924 TKAs included, 93% were performed with ALBC. Most TKAs were performed in female patients (59.5%) and patients aged 65 to 74 years (39.9%), fully cemented (92.2%), and in the 2015 to 2020 period (62.5%). All participating registries reported a cumulative 1-year revision rate for PJI of less than 1% following primary TKA with ALBC (range, 0.21%-0.80%) and with plain bone cement (range, 0.23%-0.70%). The meta-analyses based on adjusted Cox regression for 1 917 190 TKAs showed no statistically significant difference at 1 year in risk of revision for PJI (hazard rate ratio, 1.16; 95% CI, 0.89-1.52) or for all causes (hazard rate ratio, 1.12; 95% CI, 0.89-1.40) among TKAs performed with ALBC vs plain bone cement.

Conclusions and Relevance

In this study, the risk of revision for PJI was similar between ALBC and plain bone cement following primary TKA. Any additional costs of ALBC and its relative value in reducing revision risk should be considered in the context of the overall health care delivery system.

Effectiveness of antibiotic-loaded bone cement in total joint arthroplasty at a tertiary medical center: A retrospective cohort study

Background

Data regarding the effectiveness of antibiotic-loaded bone cement (ALBC) in preventing prosthetic joint infections (PJI) after total joint arthroplasty (TJA) is inconsistent. The objective of this study was to evaluate if the routine use of ALBC influenced the risk of revision surgery due to PJI.

Methods

This is a retrospective cohort study performed between January 2018 and September 2020. Adult patients aged ≥ 18 years who underwent TJA (knee or hip) and received either ALBC or plain cement (PC) were included. The outcome of this study was the rate of revision due to PJI. Multivariate analysis using logistic regression was used to identify factors that may be associated with increased risk of PJI, using STATA 15.1 (StataCorp LP, College Station, Texas, USA).

Results

A total of 844 patients were screened and 319 patients were included. There were 247 patients in ALBC group and 72 patients in the PC group. Only vancomycin powder was used in all ALBC cases, with a 2 g dose in 50% of the cases (dose ranged between 1 g and 8 g). The status of the prosthetic joint was assessed and recorded up to 2 years of the TJA. Overall, the difference in the rates of PJI between the two groups after primary arthroplasty was not statistically significant (5.6% vs 1.4%; p = 0.173; OR, 4.2; 95% CI, 0.5-33).

Conclusion

ALBC was not associated with a reduction in PJI rates after primary TJA. More research is needed to further evaluate the effectiveness of ALBC in preventing PJI.

The use of antibiotic-loaded bone cement and systemic antibiotic prophylactic use in 2,971,357 primary total knee arthroplasties from 2010 to 2020: an international register-based observational study among countries in Africa, Europe, North America, and Oceania

BACKGROUND AND PURPOSE

Antibiotic-loaded bone cement (ALBC) and systemic antibiotic prophylaxis (SAP) have been used to reduce periprosthetic joint infection (PJI) rates. We investigated the use of ALBC and SAP in primary total knee arthroplasty (TKA).

PATIENTS AND METHODS

This observational study is based on 2,971,357 primary TKAs reported in 2010-2020 to national/regional joint arthroplasty registries in Australia, Denmark, Finland, Germany, Italy, the Netherlands, New Zealand, Norway, Romania, South Africa, Sweden, Switzerland, the UK, and the USA. Aggregate-level data on trends and types of bone cement, antibiotic agents, and doses and duration of SAP used was extracted from participating registries.

RESULTS

ALBC was used in 77% of the TKAs with variation ranging from 100% in Norway to 31% in the USA. Palacos R+G was the most common (62%) ALBC type used. The primary antibiotic used in ALBC was gentamicin (94%). Use of ALBC in combination with SAP was common practice (77%). Cefazolin was the most common (32%) SAP agent. The doses and duration of SAP used varied from one single preoperative dosage as standard practice in Bolzano, Italy (98%) to 1-day 4 doses in Norway (83% of the 40,709 TKAs reported to the Norwegian arthroplasty register).

CONCLUSION

The proportion of ALBC usage in primary TKA varies internationally, with gentamicin being the most common antibiotic. ALBC in combination with SAP was common practice, with cefazolin the most common SAP agent. The type of ALBC and type, dose, and duration of SAP varied among participating countries.

Antimicrobials in polymethylmethacrylate: from prevention to prosthetic joint infection treatment: basic principles and risk of resistance

BACKGROUND

Excellent revisions about antibiotic-loaded bone cement (ALBC) have been recently published. In the present article, we review the principles and limitations of local antibiotic delivery in the context of recent advances in the pathogenesis of prosthetic joint infections (PJI), with particular attention paid to the potential association between ALBC and antimicrobial resistance.

MAIN BODY

Recalcitrance of PJI is related to the ability of pathogens to adapt to particular environments present in bone tissue and protect themselves from host immunity in different ways. Accordingly, delivery of high local antimicrobial concentrations using ALBC is needed. Most relevant clinical data showing the efficacy of ALBC for PJI prophylaxis and treatment are reviewed, and we dissected the limitations on the basis of the recent findings from animal models and suggested that aminoglycosides, in particular, could not be the best option. One of the major concerns associated with ALBC is the emergence of resistance because of theoretical prolonged exposure to low antibiotic concentrations. We summarize the mechanisms for the selection of resistant microorganisms, and we critically reviewed the evidence from animal models and clinical data from observational and registry studies and concluded that there is no evidence to support this association.

CONCLUSION

While waiting for better evidence from well-designed clinical trials, ALBC shows a beneficial effect as a prophylaxis in arthroplasty, and to avoid the colonization of spacers used for two-stage revision in patients with PJI. Experimental models and clinical evidence suggest the need to achieve high local antimicrobial concentrations to obtain the highest prophylactic and therapeutic effect. The current evidence does not support the risk of increasing resistance with use of ALBC. In the future, it is necessary to evaluate new carriers and different antimicrobials to improve clinical outcomes.

Rheumatoid Arthritis-Linked Artificial Joint Infections Leading to Amputations

Rheumatoid arthritis (RA) is a common autoimmune condition that can rarely cause more serious complications, such as permanent joint damage or infection, and may pose a significant additional risk during certain routine procedures. One major consequence of RA is that it can lead to serious and permanent joint damage requiring arthroplasty. Additionally, RA is a known cause of infection, with orthopedic prosthetic joint infections (PJIs) being documented. We explore one such serious case of a patient with long-term RA and a left knee joint replacement who presented to the emergency room with a serious PJI. History revealed that he repeatedly was affected by infections and had an extensive and severe clinical course, including nine revision surgeries. After a physical examination, imaging was performed, which further supported the diagnosis of joint infection. Considering the extensive number of attempts to salvage the joint, clinicians decided an above-knee amputation was necessary. This case highlights the fact that RA both increases the need for orthopedic arthroplasties and the risk of complications from these procedures, complicating clinical decision-making for physicians. Additionally, this patient had other underlying medical conditions and social habits that may have contributed to his severe clinical course, and we hope to explore these, discuss possible methods of modifying them, and assist clinicians in not only better treating similar patients but also emphasizing the importance of further developing standardized predictive algorithms and scoring tools.

Infection after total joint replacement of the hip and knee: research programme including the INFORM RCT

Background

People with severe osteoarthritis, other joint conditions or injury may have joint replacement to reduce pain and disability. In the UK in 2019, over 200,000 hip and knee replacements were performed. About 1 in 100 replacements becomes infected, and most people with infected replacements require further surgery.

Objectives

To investigate why some patients are predisposed to joint infections and how this affects patients and the NHS, and to evaluate treatments.

Design

Systematic reviews, joint registry analyses, qualitative interviews, a randomised controlled trial, health economic analyses and a discrete choice questionnaire.

Setting

Our studies are relevant to the NHS, to the Swedish health system and internationally.

Participants

People with prosthetic joint infection after hip or knee replacement and surgeons.

Interventions

Revision of hip prosthetic joint infection with a single- or two-stage procedure.

Main outcome measures

Long-term patient-reported outcomes and reinfection. Cost-effectiveness of revision strategies over 18 months from two perspectives: health-care provider and Personal Social Services, and societal.

Data sources

National Joint Registry; literature databases; published cohort studies; interviews with 67 patients and 35 surgeons; a patient discrete choice questionnaire; and the INFORM (INFection ORthopaedic Management) randomised trial.

Review methods

Systematic reviews of studies reporting risk factors, diagnosis, treatment outcomes and cost comparisons. Individual patient data meta-analysis.

Results

In registry analyses, about 0.62% and 0.75% of patients with hip and knee replacement, respectively, had joint infection requiring surgery. Rates were four times greater after aseptic revision. The costs of inpatient and day-case admissions in people with hip prosthetic joint infection were about five times higher than those in people with no infection, an additional cost of > £30,000. People described devastating effects of hip and knee prosthetic joint infection and treatment. In the treatment of hip prosthetic joint infection, a two-stage procedure with or without a cement spacer had a greater negative impact on patient well-being than a single- or two-stage procedure with a custom-made articulating spacer. Surgeons described the significant emotional impact of hip and knee prosthetic joint infection and the importance of a supportive multidisciplinary team. In systematic reviews and registry analyses, the risk factors for hip and knee prosthetic joint infection included male sex, diagnoses other than osteoarthritis, high body mass index, poor physical status, diabetes, dementia and liver disease. Evidence linking health-care setting and surgeon experience with prosthetic joint infection was inconsistent. Uncemented fixation, posterior approach and ceramic bearings were associated with lower infection risk after hip replacement. In our systematic review, synovial fluid alpha-defensin and leucocyte esterase showed high diagnostic accuracy for prosthetic joint infection. Systematic reviews and individual patient data meta-analysis showed similar reinfection outcomes in patients with hip or knee prosthetic joint infection treated with single- and two-stage revision. In registry analysis, there was a higher rate of early rerevision after single-stage revision for hip prosthetic joint infection, but, overall, 40% fewer operations are required as part of a single-stage procedure than as part of a two-stage procedure. The treatment of hip or knee prosthetic joint infection with early debridement and implant retention may be effective in > 60% of cases. In the INFORM randomised controlled trial, 140 patients with hip prosthetic joint infection were randomised to single- or two-stage revision. Eighteen months after randomisation, pain, function and stiffness were similar between the randomised groups (p = 0.98), and there were no differences in reinfection rates. Patient outcomes improved earlier in the single-stage than in the two-stage group. Participants randomised to a single-stage procedure had lower costs (mean difference –£10,055, 95% confidence interval –£19,568 to –£542) and higher quality-adjusted life-years (mean difference 0.06, 95% confidence interval –0.07 to 0.18) than those randomised to a two-stage procedure. Single-stage was the more cost-effective option, with an incremental net monetary benefit at a threshold of £20,000 per quality-adjusted life-year of £11,167 (95% confidence interval £638 to £21,696). In a discrete choice questionnaire completed by 57 patients 18 months after surgery to treat hip prosthetic joint infection, the most valued characteristics in decisions about revision were the ability to engage in valued activities and a quick return to normal activity.

Limitations

Some research was specific to people with hip prosthetic joint infection. Study populations in meta-analyses and registry analyses may have been selected for joint replacement and specific treatments. The INFORM trial was not powered to study reinfection and was limited to 18 months’ follow-up. The qualitative study subgroups were small.

Conclusions

We identified risk factors, diagnostic biomarkers, effective treatments and patient preferences for the treatment of hip and knee prosthetic joint infection. The risk factors include male sex, diagnoses other than osteoarthritis, specific comorbidities and surgical factors. Synovial fluid alpha-defensin and leucocyte esterase showed high diagnostic accuracy. Infection is devastating for patients and surgeons, both of whom describe the need for support during treatment. Debridement and implant retention is effective, particularly if performed early. For infected hip replacements, single- and two-stage revision appear equally efficacious, but single-stage has better early results, is cost-effective at 18-month follow-up and is increasingly used. Patients prefer treatments that allow full functional return within 3–9 months.

Future work

For people with infection, develop information, counselling, peer support and care pathways. Develop supportive care and information for patients and health-care professionals to enable the early recognition of infections. Compare alternative and new treatment strategies in hip and knee prosthetic joint infection. Assess diagnostic methods and establish NHS diagnostic criteria.

Study registration

The INFORM randomised controlled trial is registered as ISRCTN10956306. All systematic reviews were registered in PROSPERO (as CRD42017069526, CRD42015023485, CRD42018106503, CRD42018114592, CRD42015023704, CRD42017057513, CRD42015016559, CRD42015017327 and CRD42015016664).

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 10, No. 10. See the NIHR Journals Library website for further project information.

Comprehensive meta-analysis of antibiotic-impregnated bone cement versus plain bone cement in primary total knee arthroplasty for preventing periprosthetic joint infection

PURPOSE

Antibiotic-loaded bone cement (ALBC) was usually used to prevent periprosthetic joint infection (PJI) in primary total knee arthroplasty (PTKA), but whether to use ALBC or plain bone cement in PTKA remains unclear. We aimed to compare the occurrence rate of PJI using two different cements, and to investigate the efficacy of different antibiotic types and doses administered in preventing surgical site infection (SSI) with ALBC.

METHODS

The availability of ALBC for preventing PJI was evaluated by using a systematic review and meta-analysis referring to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Existing articles until December 2021 involving PTKA patients with both ALBC and plain bone cement cohorts were scanned by searching "total knee arthroplasty", "antibiotic-loaded cement", "antibiotic prophylaxis", "antibiotic-impregnated cement" and "antibiotic-laden cement" in the database of PubMed/MEDLINE, Embase, Web of Science and the Cochrane Library. Subgroup analysis included the effectiveness of different antibiotic types and doses in preventing SSI with ALBC. The modified Jadad scale was employed to score the qualities of included articles.

RESULTS

Eleven quantitative studies were enrolled, including 34,159 knees undergoing PTKA. The meta-analysis results demonstrated that the use of prophylactic ALBC could significantly reduce the prevalence of deep incisional SSI after PTKA, whereas there was no significant reduction in the rate of superficial incisional SSI. Moreover, gentamicin-loaded cement was effective in preventing deep incisional SSI, and the use of high-dose ALBC significantly reduced the rate of deep incisional SSI after PTKA. Besides, no significant adverse reactions and complications were stated during the use of ALBC in PTKA.

CONCLUSION

The preventive application of ALBC during PTKA could reduce the rates of deep PJI. Furthermore, bone cement containing gentamicin and high-dose ALBC could even better prevent deep infection after PTKA. However, the existing related articles are mostly single-center and retrospective studies, and further high-quality ones are needed for confirmation.

Risk Factors for Periprosthetic Joint Infection after Primary Total Knee Arthroplasty

Periprosthetic joint infection (PJI) is a major adverse event of primary total knee arthroplasty (TKA) from the patient's perspective, and it is also costly for health care systems. In 2010, the reported incidence of PJI in the first 2 years after TKA was 1.55%, with an incidence of 0.46% between the second and tenth year. In 2022, it has been published that 1.41% of individuals require revision TKA for PJI. The following risk factors have been related to an increased risk of PJI: male sex, younger age, type II diabetes, obesity class II, hypertension, hypoalbuminemia, preoperative nutritional status as indicated by prognostic nutritional index (PNI) and body mass index, rheumatoid arthritis, post-traumatic osteoarthritis, intra-articular injections prior to TKA, previous multi-ligament knee surgery, previous steroid therapy, current tobacco use, procedure type (bilateral), length of stay over 35 days, patellar resurfacing, prolonged operative time, use of blood transfusions, higher glucose variability in the postoperative phase, and discharge to convalescent care. Other reported independent risk factors for PJI (in diminishing order of importance) are congestive heart failure, chronic pulmonary illness, preoperative anemia, depression, renal illness, pulmonary circulation disorders, psychoses, metastatic tumor, peripheral vascular illness, and valvular illness. Preoperative intravenous tranexamic acid has been reported to diminish the risk of delayed PJI. Knowing the risk factors for PJI after TKA, especially those that are avoidable or controllable, is critical to minimizing (ideally preventing) this complication. These risk factors are outlined in this article.

Effectiveness of antibiotics loaded bone cement in primary total knee arthroplasty: A systematic review and meta-analysis

INTRODUCTION

The application of antibiotics loaded bone cement (ALBC) in the revision of failed total knee arthroplasty (TKA) has been widely accepted to reduce risk of peri-prosthetic infection. However, the prophylactic use of ALBC in primary TKA remains controversial. This study was aimed to identify the prophylactic effect on peri-prosthetic infection and safety of ALBC in primary TKA.

HYPOTHESIS

The application of ALBC could reduce the risk of peri-prosthetic infection in primary TKA.

MATERIALS AND METHODS

Electronic platforms including PubMed, EMBASE, and CENTRAL were retrieved to identify studies comparing outcomes of prophylactic ALBC and plain cement in primary TKA. For outcomes reported as dichotomous variable and continuous variable, risk ratio (RR) and weighted mean difference (WMD) as well as their 95% confidence intervals (95% CI) were selected as the effect sizes for pooling. While for those outcomes reported the adjusted effect sizes such as odds ratio (OR, derived from multivariate logistic regression), and hazard ratio (HR, derived from multivariate COX proportional hazard model), the reported effect sizes were selected for pooling.

RESULTS

A total of 17 studies with 2,074,844 patients (1,093,920 in ALBC group and 980,924 in plain cement group) were eligible for final inclusion. No significant difference was found between ALBC and plain cement groups both for the unadjusted (RR=1.02, 95% CI: 0.86∼1.21, p=0.832) and adjusted (OR=0.94, 95% CI: 0.76∼1.17, p=0.596) peri-prosthetic infection rate. ALBC application was related to significantly increased length of hospital stay (WMD=0.13, 95% CI: 0.10∼0.17, p<0.001). There was no significance on the difference of operation related adverse events between two groups (RR=1.31, 95% CI: 0.68∼2.52, p=0.420). Significantly increased risks of acute renal failure and readmission, and temporarily increased ototoxicity in ALBC group were reported in one of the primary study.

DISCUSSION

There is no sufficient evidence supporting decreased peri-prosthetic infection rate with ALBC application in primary TKA. What's more, it must be taken into consideration about the safety and added cost of additional impregnated antibiotics.

LEVEL OF EVIDENCE

III; meta-analysis.

Pharmacological thromboprophylaxis as a risk factor for early periprosthetic joint infection following primary total joint arthroplasty

Venous thromboembolism (VTE) prophylaxis has been suggested for patients who underwent total join arthroplasty (TJA). However, the morbidity of surgical site complications (SSC) and periprosthetic joint infection (PJI) has not been well evaluated. We aimed to evaluate the impact of VTE prophylaxis on the risk of early postoperative SSC and PJI in a Taiwanese population. We retrospectively reviewed 7511 patients who underwent primary TJA performed by a single surgeon from 2010 through 2019. We evaluated the rates of SSC and PJI in the early postoperative period (30-day, 90-day) as well as 1-year reoperations. Multivariate regression analysis was used to identify possible risk factors associated with SSC and PJI, including age, sex, WHO classification of weight status, smoking, diabetes mellitus (DM), rheumatoid arthritis(RA), Charlson comorbidity index (CCI), history of VTE, presence of varicose veins, total knee or hip arthroplasty procedure, unilateral or bilateral procedure, or receiving VTE prophylaxis or blood transfusion. The overall 90-day rates of SSC and PJI were 1.1% (N = 80) and 0.2% (N = 16). VTE prophylaxis was a risk factor for 90-day readmission for SSC (aOR: 1.753, 95% CI 1.081-2.842), 90-day readmission for PJI (aOR: 3.267, 95% CI 1.026-10.402) and all 90-day PJI events (aOR: 3.222, 95% CI 1.200-8.656). Other risk factors included DM, underweight, obesity, bilateral TJA procedure, younger age, male sex and RA. Pharmacological thromboprophylaxis appears to be a modifiable risk factor for SSC and PJI in the early postoperative period. The increased infection risk should be carefully weighed in patients who received pharmacological VTE prophylaxis.

Diagnosing Periprosthetic Joint Infection: a Scoping Review

PURPOSE OF REVIEW

The goal of this review is to provide an up to date understanding of the utility and limitations of the current tests utilized in the diagnosis of periprosthetic joint infection (PJI) in total knee and hip arthroplasty.

RECENT FINDINGS

Despite the growth in literature surrounding PJI diagnosis, there remains challenges in establishing a diagnosis of PJI. A combination of clinical, serum, and synovial tests and microbiologic and histologic examinations can yield a diagnosis in the majority of cases. Novel molecular and imaging studies may be beneficial for indeterminant cases. A number of emerging diagnostic tests have been proposed and may be incorporated into diagnostic algorithms in the future. Recently proposed stepwise diagnostic algorithms have shown high sensitivity and specificity. The diagnosis of PJI remains challenging due to a lack of tests that can definitively rule out infection. Diagnosis and investigations should occur in a stepwise fashion. There has been a plethora of new diagnostic tests introduced in attempts to improve the accuracy of diagnostic algorithms. The definition and algorithms for the diagnoses of PJI will continue to evolve as new techniques and tests are introduced.

Osteoblastic differentiation and bactericidal activity are enhanced by erythromycin released from PCL/PLGA-PVA coaxial nanofibers

Prosthesis with antibiotic-eluting nanofibrous (NF) coating represents coating alternative to prevent periprosthetic joint infection (PJI). In this study, four formulas of erythromycin (EM)-embedded both in core and sheath components of coaxial PCL/PLGA-PVA NF coatings were developed: EM 0 (no EM), EM 100 (100 μg/mL), EM500 (500 μg/mL) and EM1000 (1000 μg/mL). EM doping altered the physicochemical and structural properties of NFs to some extent, including the increase of NF porosity and surface wettability. A sustained EM release from EM-NFs for >4 weeks was observed. Eluents collected from EM-NFs showed strong zone of inhibition (ZOI) to Staphylococcus aureus growth and the sizes of ZOI positively related to the amount of EM released. EM-NFs were nontoxic to rat bone marrow stem cells (rBMSCs). Cell growth was significantly enhanced when comparing rBMSCs cultured on EM-NFs (EM0 and EM 100) to those cultured on NF-free control. Cell differentiation (ALP activity) was notably enhanced by EM100, compared to control and EM0. Eluents from EM-NFs on rBMSCs were also investigated. The presence of 10% EM-NF eluents inhibited the growth of rBMSCs, which was proportional to the amount of EM doped. The ALP activity was notably enhanced by eluents from EM-NFs with the highest activity in EM100 compared to control and EM0. Our data indicate that EM-doped PCL/PLGA-PVA coaxial NF coatings have a great potential to be applied as a new implant coating matrices. Further in vivo testing in animal models is currently planned that should represent the first step in predicting the clinical outcomes of EM-eluting NF coating approach.

Incidence and Predictors of Prosthetic Joint Infection Following Primary Total Knee Arthroplasty: A 15-Year Population-Based Cohort Study

BACKGROUND

One of the most devastating complications of total knee arthroplasty (TKA) is periprosthetic joint infection (PJI). Although many complications associated with TKA have decreased over time, the trends associated with PJI are less clear. Thus, the purpose of this study is to determine the incidence and risk factors for PJI after primary TKA.

METHODS

We performed a population-based cohort study using linked administrative databases in Ontario, Canada. We used a Cox proportional hazards model to analyze the effect of surgical factors and patient factors on the risk of developing PJI.

RESULTS

In total, 129,613 patients aged 50+ received a primary TKA for osteoarthritis from 2002 to 2016 in Ontario, Canada. In total, 1.41% of patients underwent revision surgery for PJI. When accounting for censoring, the cumulative incidence for PJI was 0.51% (95% confidence interval 0.46-0.55) at 1 year, 1.12% (1.05-1.18) at 5 years, 1.49% (1.41-1.57) at 10 years, and 1.65% (1.55-1.75) at 15 years. The multivariable model revealed that male gender, younger age, type II diabetes, post-traumatic arthritis, patellar resurfacing, and discharge to convalescent care were associated with increased risk of PJI.

CONCLUSION

The risk of PJI following TKA has decreased in small but steady increments over the past 15 years. Most PJIs are diagnosed within the first 2 years postoperatively, though a small group do continue to occur after 10 years. Overall, while the incidence of PJI has decreased slightly over the past 15 years, it remains among the most concerning complications of TKA and continued efforts aimed at further reducing its occurrence are needed.

Properties of erythromycin-loaded polymeric dicalcium phosphate dehydrate bone graft substitute

A self-setting, injectable polymeric dicalcium phosphate dehydrate bone graft substitute that is mechanically strong and has excellent cohesion was developed. We assessed the performance of erythromycin-loaded polymeric dicalcium phosphate dehydrate cement. Its properties include drug release, growth inhibition against Staphylococcus aureus and biocompatibility with osteoblastic MC3T3 cells. The impact of erythromycin loading on cement injectability, setting time, and mechanical strength were also evaluated. A sustained, low burst release of erythromycin was observed. Eluents collected from erythromycin-loaded cement showed a considerable zone of inhibition for up to 28 days. Direct contact of erythromycin-loaded cement discs with agar plate showed a similarly sizable zone of inhibition for up to 22 days. Degraded ceramic residues had strong zones of inhibition as well. While the erythromycin-loaded cement was injectable, a notable delay of the setting time was observed (49.2 ± 6.8 min) as compared with control (drug-free cement, 12.2 ± 2.6 min). A slight increase in compressive strength (60.83 ± 6.28 MPa) was observed in erythromycin-loaded cement as compared with control (59.41 ± 6.48 MPa). Erythromycin-loaded cement was biocompatible although reduced cell growth was observed in the presence of the cement eluent. We propose that the bactericidal efficacy of erythromycin-loaded cement was caused by the combined effects of erythromycin released and exposed on the contact surface of degrading ceramics. Our data may elucidate the future application of polymeric dicalcium phosphate dehydrate bone graft substitute for the treatment of orthopedic infections and opportunities to use other antibiotics and applications considering its comparable handling and mechanical strength to poly (methyl methacrylate) cements.

Fragility Index as a Measure of Randomized Clinical Trial Quality in Adult Reconstruction: A Systematic Review

Background

The Fragility Index (FI) and Reverse Fragility Index are powerful tools to supplement the P value in evaluation of randomized clinical trial (RCT) outcomes. These metrics are defined as the number of patients needed to change the significance level of an outcome. The purpose of this study was to calculate these metrics for published RCTs in total joint arthroplasty (TJA).

Methods

We performed a systematic review of RCTs in TJA over the last decade. For each study, we calculated the FI (for statistically significant outcomes) or Reverse Fragility Index (for nonstatistically significant outcomes) for all dichotomous, categorical outcomes. We also used the Pearson correlation coefficient to evaluate publication-level variables.

Results

We included 104 studies with 473 outcomes; 92 were significant, and 381 were nonstatistically significant. The median FI was 6 overall and 4 and 7 for significant and nonsignificant outcomes, respectively. There was a positive correlation between FI and sample size (R = 0.14, P = .002) and between FI and P values (R = 0.197, P = .000012).

Conclusions

This study is the largest evaluation of FI in orthopedics literature to date. We found a median FI that was comparable to or higher than FIs calculated in other orthopedic subspecialties. Although the mean and median FIs were greater than the 2 recommended by the American Academy of Orthopaedic Surgeons Clinical Practice Guidelines to demonstrate strong evidence, a large percentage of studies have an FI < 2. This suggests that the TJA literature is on par or slightly better than other subspecialties, but improvements must be made.

Level of Evidence

Level I; Systematic Review.

The use of 2-octyl cyanoacrylate as an adjuvant to wound closure in total knee arthroplasty

PURPOSE

The efficacy of the use of 2-octyl cyanoacrylate (OCA) as an adjuvant to wound closure in preventing wound complications after total knee arthroplasty (TKA) is rarely reported. This study was aimed to determine whether the use of OCA as a supplement to conventional wound closure reduces the incidence of wound complications following TKA.

PATIENTS AND METHODS

This retrospective study reviewed 1106 consecutive patients who underwent TKA for symptomatic end-stage osteoarthritis (OA) between 2012 and 2017. The first 562 patients who did not receive OCA were grouped into the Control group, and the subsequent 544 patients who received OCA as an adjuvant to wound closure were grouped into the OCA group. All patients were followed up for at least 2 years. The main outcome was the development of operative site complications, including aseptic and infectious complications. Aseptic wound complications were wound leakage, hematoma, wound dehiscence and delayed wound healing, and infectious complication was mainly referred to the superficial infection.

RESULTS

No significant difference with regard to hematoma was observed between groups (3.0% vs. 3.7%, P = 0.617, φ = - 0.02). The incidences were significantly higher in the Control group versus the OCA group in regard to wound leakage (9.4% vs. 2.0%, P = 0.000, φ = 0.16), wound dehiscence (5.7% vs. 1.3%, P = 0.000, φ = 0.12), delayed wound healing (4.4% vs. 1.5%, P = 0.004, φ = 0.09) and superficial infection (2.0% vs. 0.4%, P = 0.022, φ = 0.07). No serious adverse events (AEs) occurred.

CONCLUSIONS

The present study showed that the addition of OCA reduced the incidence of wound leakage, wound dehiscence, delayed wound healing and superficial infection after TKA compared to conventional wound closure. Based on the outcomes above, we decide to use OCA routinely for wound closure after TKA.

LEVEL OF EVIDENCE

III, retrospective, cohort study.

Antibiotic-Loaded Bone Cement in Prevention of Periprosthetic Joint Infections in Primary Total Knee Arthroplasty: A Register-based Multicentre Randomised Controlled Non-inferiority Trial (ALBA trial)

INTRODUCTION

The current evidence on the efficacy of antibiotic-loaded bone cement (ALBC) in reducing the risk of periprosthetic joint infections (PJI) after primary joint reconstruction is insufficient. In several European countries, the use of ALBC is routine practice unlike in the USA where ALBC use is not approved in low-risk patients. Therefore, we designed a double-blinded pragmatic multicentre register-based randomised controlled non-inferiority trial to investigate the effects of ALBC compared with plain bone cement in primary total knee arthroplasty (TKA).

METHODS AND ANALYSIS

A minimum of 9,172 patients undergoing full-cemented primary TKA will be recruited and equally randomised into the ALBC group and the plain bone cement group. This trial will be conducted in Norwegian hospitals that routinely perform cemented primary TKA. The primary outcome will be risk of revision surgery due to PJI at 1-year of follow-up. Secondary outcomes will be: risk of revision due to any reason including aseptic loosening at 1, 6, 10 and 20 years of follow-up; patient-related outcome measures like function, pain, satisfaction and health-related quality of life at 1, 6 and 10 years of follow-up; risk of changes in the microbial pattern and resistance profiles of organisms cultured in subsequent revisions at 1, 6, 10 and 20 years of follow-up; cost-effectiveness of routine ALBC versus plain bone cement use in primary TKA. We will use 1:1 randomisation with random permuted blocks and stratify by participating hospitals to randomise patients to receive ALBC or plain bone cement. Inclusion, randomisation and follow-up will be through the Norwegian Arthroplasty Register.

ETHICS AND DISSEMINATION

The trial was approved by the Western Norway Regional Committees on Medical and Health Research Ethics (reference number: 2019/751/REK vest) on 21 June 2019. The findings of this trial will be disseminated through peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

NCT04135170.

The effect of antibiotic-loaded bone cement on risk of revision following hip and knee arthroplasty

AIMS

This study aimed to compare the effect of antibiotic-loaded bone cement (ALBC) versus plain bone cement (PBC) on revision rates for periprosthetic joint infection (PJI) and all-cause revisions following primary elective total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

MEDLINE, Embase, Web of Science, and Cochrane databases were systematically searched for studies comparing ALBC versus PBC, reporting on revision rates for PJI or all-cause revision following primary elective THA or TKA. A random-effects meta-analysis was performed. The study was registered in the International Prospective Register of Systematic Reviews (PROSPERO ID CRD42018107691).

RESULTS

Nine studies and one registry report were identified, enabling the inclusion of 371,977 THA and 671,246 TKA. Pooled analysis for THA demonstrated ALBC was protective against revision for PJI compared with PBC (relative risk (RR) 0.66, 95% confidence interval (CI) 0.56 to 0.77; p < 0.001), however, no differences were seen for all-cause revision rate (RR 0.62, 95% CI 0.35 to 1.09; p = 0.100). For TKA, there were no significant differences in revision rates for PJI or all causes between ALBC and PBC (RR 0.92, 95% CI 0.59 to 1.45; p = 0.730, and RR 0.73, 95% CI 0.53 to 1.02; p = 0.060, respectively).

CONCLUSION

ALBC demonstrated a protective effect against revision for PJI compared with PBC in THA with no difference in all-cause revisions. No differences in revision rates for PJI and all-cause revision between ALBC and PBC for TKA were observed. Cite this article: Bone Joint J 2021;103-B(1):7-15.

Systematic Review and Meta-Analysis of Tobacco Use as a Risk Factor for Prosthetic Joint Infection After Total Hip Replacement

Background

A prosthetic joint infection (PJI) is one of the possible complications after total hip arthroplasty (THA). Several studies, but not all, have reported smoking as a risk factor of PJIs in orthopaedic surgery. This study summarizes the most recent evidence using a systematic review of whether tobacco use (not only tobacco smoking) is a risk factor in developing PJIs, specifically after THA.

Methods

Ovid Medline, EMBASE, Scopus, Web of Science, and Cochrane databases were searched from inception to July 2019 to identify case-control studies that examined the PJI risk in tobacco users and tobacco nonusers undergoing THA. Publication bias was also assessed through funnel plots.

Results

Searches identified 2689 articles, and 10 of these, involving a total of 20,640 patients, met the inclusion criteria. The overall odds ratio (pooled odds ratio) to develop either a superficial infection, a deep infection, or an infection requiring revision surgery for tobacco users vs nonusers was 1.54 (95% confidence interval: 1.25-1.91) when a fixed-effect model was used and 1.56 (95% confidence interval: 1.10-2.21) when a random-effect model was used. No publication bias was observed among the identified studies.

Conclusions

The findings of the study indicated that tobacco use is associated with a higher risk of PJIs in patients undergoing THA.

Local antibiotics in primary hip and knee arthroplasty: a systematic review and meta-analysis

BACKGROUND

Infection is a truly devastating complication of total joint arthroplasty, causing most patients to undergo a revision surgery, and to bear significant psychological and financial burden. The purpose of this study is to systematically evaluate the literature to determine the efficacy and complication profile of local antibiotic application in primary total joint arthroplasty.

METHODS

All studies of primary total joint arthroplasty which assessed local antibiotics in any form other than antibiotic-impregnated cement as an intervention were included. Studies that reported at least one outcome related to infection and were available in full text in English were eligible for inclusion. Studies which included both primary and revision cases but did not report the stratified data for each type of surgery and studies on fracture populations were excluded.

RESULTS

A total of 9 studies involving 3,714 cases were included. The pooled deep infection rate was 1.6% in the intervention groups and 3.5% in the control groups. Meta-analysis revealed a RR of 0.53 (95%CI: 0.35-0.79, p = 0.002) with no heterogeneity (I² = 0%) for infection in the intervention groups. Meta-analysis revealed a non-significant reduction in superficial infection rates in the intervention groups; however, there was a significant increase in aseptic wound complications in the intervention groups.

CONCLUSION

Local antibiotic application results in a moderate reduction in deep infection rates in primary total joint arthroplasty, with no significant impact on superficial infection rates. However, local antibiotic application may be associated with a moderate increase in aseptic wound complications.

An Assessment of Randomized Controlled Trial Quality in The Journal of Bone & Joint Surgery: Update from 2001 to 2013

BACKGROUND

The quality of reporting of randomized controlled trials (RCTs) published in The Journal of Bone & Joint Surgery (JBJS) from 1988 to 2000 was previously analyzed. The purpose of this current study was to analyze the quality of reporting of RCTs published in JBJS from 2001 to 2013 to identify trends over time and potential areas of improvement for future clinical trials.

METHODS

A manual search of the JBJS database identified RCTs published between January 2001 and December 2013. Quality assessments, using the Detsky quality-of-reporting index (Detsky score), a modified Cochrane risk-of-bias tool, and abstraction of relevant data identifying predictors of quality, were conducted.

RESULTS

A total of 5,780 publications were identified in JBJS from 2001 to 2013, with 285 RCTs (4.9%), representing an increase from the prior 13-year period. The overall mean transformed Detsky score (and standard error) increased significantly (p < 0.001) from 68.1% ± 1.67% to 76.24% ± 0.72%. The percentage of multicenter RCTs decreased from 67% to 31%. The percentage of positive trials also decreased from 80% to 50.5%, as did the mean sample size (212 to 166). Regression analysis indicated that trials with an epidemiologist as the first author and nonsurgical trials were significantly associated (p = 0.001) with a higher overall trial quality score. The categories of the lowest mean methodology scores were randomization and concealment, eligibility criteria, and reasons for patient exclusion, as identified with the Detsky score, and patient and assessor blinding, as identified with the risk-of-bias assessment.

CONCLUSIONS

The quantity and quality of published RCTs in JBJS have increased in the 2001 to 2013 time period compared with the previous time period. Although these improvements are encouraging, trends to smaller, single-center trials were also observed. To efficiently determine the efficacy of orthopaedic treatments and limit bias, high-quality randomized trials of appropriate sample size and rigorous design are needed.

Antibiotic containing bone cement in prevention of hip and knee prosthetic joint infections: A systematic review and meta-analysis

BACKGROUND

Prosthetic joint infection (PJI) is the most serious total joint arthroplasty (TJA) complication despite several aseptic and antiseptic preventive measures. There is no clear evidence or even consensus, whether antibiotic-loaded bone cement (ALBC) should be used, in addition to systemic short-term routine antibiotic prophylaxis, to reduce the risk of PJI in primary TJA. We aimed to analyze the efficacy of ALBC for prevention of PJI in patients undergoing primary TJA.

METHODS

We searched systematically for randomized controlled trials (RCTs) in PubMed, Scopus, Embase, Web of Science and Cochrane library. Two reviewers independently screened potentially eligible studies according to predefined selection criteria and assessed the risk of bias using a modified version of the Cochrane risk of bias tool. PJI was prespecified as the primary outcome of interest. The meta-analyses were based on risk ratios using random-effects model per default. For the purpose of sensitivity, the corresponding fixed effects model odds ratios were calculated with the use of the Peto method as well. To evaluate a potential difference in effect sizes using different types (subgroups) of antibiotics used in bone cement, and at different follow-up periods, we performed stratified meta-analyses.

RESULTS

Thirty-seven studies were eligible for the systematic review and qualitative synthesis, and 9 trials (6507 total joint arthroplasties) were included in this meta-analysis. Overall ALBC significantly reduced the risk of PJI following primary TJAs (RRs, 0.36; 95% CIs, 0.16 to 0.80; P = 0.01) with a moderate degree of inconsistency (I2 = 47%). Based on stratified meta-analyses the use of gentamicin appeared to have a better effect (P = 0.0005) in the total hip arthroplasty. Pooled data of different antibiotics used in knee arthroplasties showed a significant association of cefuroxime (RRs, 0.08; 95% CIs, 0.01 to 0.63; P = 0.02). Further, ALBCs significantly reduced the PJI at one and two years of follow-up (P = 0.03 and P = 0.005 respectively).

CONCLUSIONS

The evidence suggests that ALBCs are effective in reducing the PJI following primary TJA; i.e. between 20 and 84% reduced risk. However, the clear limitations of the available trial evidence highlight the need for joint-specific confirmatory trials, that will need to be designed as cluster-randomized trials of clinics in countries with well-functioning arthroplasty registries.The translational potential of this article: This meta-analysis highlights the prophylactic potential of ALBCs in lowering the risk of infection following primary hip or knee arthroplasties but emphasizes the need for more recent confirmatory trials.

The Impact of Antibiotic-Loaded Bone Cement on Antibiotic Resistance in Periprosthetic Knee Infections

Backgroud

Antibiotic-loaded bone cement (ALBC) is commonly used in total knee arthroplasty (TKA), especially among high-risk patients. While previous studies have reported on the efficacy of ALBC in reducing the rate of periprosthetic joint infection (PJI), its impact on antibiotic resistance has not been determined. The purpose of this study was to investigate antibiotic resistance among organisms causing PJIs after TKA in which ALBC was utilized.

Methods

A retrospective review from December 1998 through December 2017 identified 36 PJIs that met inclusion criteria. Patients with culture-negative infection and unknown cement type were excluded. Patient characteristics, infecting organism, and antibiotic susceptibilities were recorded. ABLC included an aminoglycoside in all cases.

Results

There was no difference in the type of PJI between the 2 groups. Staphylococcus species was the most commonly isolated, with 9 of 16 cases (56.3%) using non-ALBC and 14 of 20 (65.0%) cases using ALBC. Of those infected with Staphylococcus, there was no significant difference in antibiotic susceptibilities between groups. Overall, there were only 3 cases where the infecting organism was aminoglycoside resistant (standard cement, 1; ALBC, 2).

Conclusions

These results suggest that the use of ALBC does not increase the risk of antibiotic resistance or affect the pattern of infection, even as the use of ALBC continues to increase, particularly among high-risk patients.

Overview of Randomized Controlled Trials in Total Knee Arthroplasty (47,675 Patients): What Have We Learnt?

BACKGROUND

The aim of this study is to provide an overview of randomized controlled trials (RCTs) in primary total knee arthroplasty summarizing the available high-quality evidence.

METHODS

Following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we searched the Cochrane Central Register of Controlled Trials (CENTRAL, 2019, Issue 3), Ovid MEDLINE, and Embase. We excluded nonrandomized trials, trials on unicompartmental knee arthroplasty or revision surgery, systematic reviews, and meta-analyses. Trials that met our inclusion criteria were assessed using a binary outcome measure of whether they reported statistically significant findings. These were then classified according to the intervention groups (surgical approach, tourniquet use, design, etc.).

RESULTS

Four hundred and three RCTs met the inclusion criteria and were included. The total number of patients in those 403 RCTs was 47,675. Only 33 RCTs (8.2%) reported significant differences between the intervention and the control groups. The trials were grouped into surgical approach 34, tourniquet 31, minimally invasive surgery 13, patient specific instrumentation 30, knee design 37, fixation 27, mobile bearing 47, navigation 50, polyethylene 19, technique 27, patella resurfacing 26, drain 19, closure 16, and others 27 RCTs.

CONCLUSION

For the vast majority of patients, a standard conventional total knee arthroplasty with a surgical approach familiar to the surgeon using standard well-established components, with or without tourniquet, without surgical drain leads to satisfactory long-term clinical outcomes.

Antibiotic Cement in Arthroplasty: A Meta-analysis of Randomized Controlled Trials

Introduction Periprosthetic joint infection (PJI) following arthroplasty surgery is a devastating complication. Antibiotic cement has been proposed as a way to reduce PJI rates. The aim of this systematic review and meta-analysis was to review all of the available randomized controlled trial (RCT) evidence on the use of antibiotic cement in arthroplasty. Methods PubMed, MEDLINE, and Embase were searched. All records were screened in triplicate. Eligible RCTs were included. Data regarding study characteristics, patient demographics, and rates of superficial and deep infection were collected. The risk of bias was assessed using the Cochrane Risk of Bias Assessment Tool 2.0. Results Five RCTs were included (n = 4,397). Four studies compared antibiotic cement to plain cement while one study compared high-dose dual-antibiotic (HDDA) cement to low-dose single-antibiotic (LDSA) cement. The mean age of included patients was 76.4 years (range: 68-83). There was no significant difference in superficial infection rates between antibiotic and plain cement (odds ratio (OR): 1.33, 95% Confidence Interval (CI): 0.77-2.30, p = 0.3). There was a large but non-significant reduction in deep infection rates for antibiotic cement (OR: 0.20, 95%CI: 0.03-1.32, p = 0.09). There was a significantly lower rate of infection with HDDA as compared to LDSA (OR: 0.31, 95% CI: 0.09-0.88, p = 0.041). Conclusion The available evidence from RCTs reveals a potential benefit for antibiotic cement in arthroplasty surgery, though this difference is non-significant and highly imprecise. Furthermore, HDDA cement was significantly more effective than LDSA cement. There is a need for large, pragmatic trials on this topic.

Risk factors for periprosthetic joint infection after total knee arthroplasty

INTRODUCTION

Periprosthetic joint infection (PJI) is the most serious and feared complication in total knee arthroplasty (TKA) and can have catastrophic consequences. The number of total knee arthroplasties is increasing, so infections could also be greater in the future. The aim of this study is to identify the most relevant risk factors associated with infection after a total knee arthroplasty.

METHODS

This is a case-control study of patients who underwent total knee arthroplasty at the University Hospital of Salamanca. We included 66 TKA PJI patients and 66 control TKA patients. Demographic and clinical variables were collected. A descriptive and inferential analysis was performed by logistic regression and attributable risk fraction assessed.

RESULTS

Prolonged operative time (> 90') and tourniquet time (> 60') were the most relevant risk factors described (OR 40.77, AFE 0.97, p > 0.001 and OR 37.14, AFE 0.97, p < 0.001, respectively). The use of non-antibiotic-laded cement (OR 3.62), obesity (BMI > 30, OR 8.86), diabetes (OR 2.33), high ASA grade (III-IV, OR 15.30), and blood transfusion requirement (OR 4.60) were also statistically significant risk factors for TKA PJI.

CONCLUSIONS

Our study provides evidence concerning that operative time, tourniquet time, cement type, diabetes, obesity, ASA grade, and blood transfusion requirement as independently associated risk factors for TKA PJI. Modifiable risk factors were specifically relevant, so we should be able to reduce the infection rate.

The cost-effectiveness of antibiotic-loaded bone cement versus plain bone cement following total and partial knee and hip arthroplasty

Background

Postoperative infection is one of the most prevalent complications following total joint arthroplasty (TJA). As such procedures become more prevalent, it is imperative that we develop new prophylactic methods to prevent the need for revision procedures. In recent years, surgeons have opted to use antibiotic-loaded bone cement (ALBC) rather than plain bone cement (PBC) in primary hip and knee replacements due to its theoretical potential of lowering infection rates. However, the cost-effectiveness of this intervention remains in question.Questions/Purposes: To determine the rate of infection and cost-effectiveness of antibiotic-loaded bone cement as compared to plain bone cement in hip and knee arthroplasty.

Patients and methods

We reviewed 4116 primary hip and knee arthroplasty cases performed between 2016 and 2018 at Morristown Medical Center in New Jersey. Data regarding demographics, complications, and any readmissions due to deep infection were collected retrospectively. During that time period there were a total of 4016 knee cases (423 ALBC, 3593 PBC) and 123 hip cases (63 ALBC, 60 PBC). The average cost for one bag of antibiotic-loaded bone cement and plain bone cement for hip and knee arthroplasty was $336.42 and $72.14, respectively. A statistical analysis was performed using Fisher's exact test; the National Healthcare Safety Network (NHSN) surgical site infection guidelines were used to distinguish between superficial and deep infections.

Results

Ten patients were readmitted due to deep infection, all of whom had undergone total knee arthroplasty. Of those cases, plain bone cement was used for the index procedure in seven instances and antibiotic-loaded cement was used in three. This resulted in an infection rate of 0.19% and 0.62%, respectively, p = 0.103. There was no statistically significant difference in infection rates between the two groups. A total of 778 bags of ALBC were used in 423 knee surgeries, and 98 bags of ALBC were used in 63 hip cases. The total cost for ALBC in TKA and THA procedures was $261,734.76 (778*336.42) and $32,969.16 (98*336.42), respectively. If PBC had been used during all index procedures, it would have resulted in a total savings of $231,509.28.

Conclusions

Antibiotic-loaded cement did not significantly reduce the rate of infection for either knee or hip arthroplasty. Thus, the routine use of antibiotic-loaded cement in primary hip and knee arthroplasty may be an unnecessary financial burden to the healthcare system. A larger sample size and a randomized controlled trial would help confirm our findings and would provide further information on the cost-effectiveness of ALBC cement versus PBC.Significance/Clinical Relevance: In this review of cases performed from 2016 to 2018 there was no statistically significant difference between the rate of infection and the need for revision surgeries for patients treated with ALBC versus PBC. As hospital systems continue to transition towards a bundled payment model, it becomes imperative for providers to reduce any unnecessary costs in order to increase quality and efficiency. We estimate that our hospital system could save nearly $120,000/year by using plain bone cement instead of antibiotic-loaded cement.

Antibiotic-impregnated bone cement for preventing infection in patients receiving primary total hip and knee arthroplasty: A meta-analysis

BACKGROUND

Surgical-site infections after primary total joint arthroplasty (TJA) are a significant issue. Antibiotic-impregnated bone cement (AIBC) has been widely used for the treatment of infected joints, but routine use of AIBC in primary TJA remains controversial. In this systematic review, we evaluated the efficacy of AIBC in reducing surgical-site infections after primary TJA.

METHODS

We systematically searched Pubmed, EMbase, Cochrane Library, CMB, CNKI, and WanFang Data for studies (published until June 1, 2019) evaluating AIBC use in reducing infection rates. Two reviewers independently screened the literature according to inclusion and exclusion criteria, extracted data, and assessed the methodological quality of included studies. Meta-analysis was performed using Review Manager 5.3 software. The registration number is CRD42017078341 in PROSPERO.

RESULTS

In total, 10 studies were included, resulting in a sample size of 13,909 arthroplasty cases. The overall pooled data demonstrated that, compared with systemic antibiotics, AIBC was more effective in decreasing deep infection rates (odds ratio [OR] = 0.35, 95% confidence interval [CI] = 0.14-0.89, P = .030), although there were higher superficial infection rates with AIBC (OR = 1.53, 95% CI = 1.11-2.11, P = .010). Compared to systemic antibiotics alone, AIBC with systemic antibiotics significantly decreased deep infection rates (OR = 0.55, 95% CI = 0.41-0.75, P = .0001) but there was no difference in superficial infection rates (OR = 1.43, 95% CI = 0.81-2.54, P = .220). In the subgroup analysis, both randomized controlled trials and cohort studies had reduced deep infection rates after primary TJA (OR = 0.61, 95% CI = 0.37-0.99, P = .050 and OR = 0.49, 95% CI = 0.34-0.70, P = .0001, respectively). AIBC decreased deep infection rates in both total hip and knee arthroplasty (OR = 0.25, 95% CI = 0.12-0.52, P = .0002 and OR = 0.62, 95% CI = 0.45-0.87, P = .005, respectively). Deep infection rates were significantly decreased by AIBC with gentamicin (OR = 0.31, 95% CI = 0.20-0.49, P < .00001) but unaffected by AIBC with cefuroxime (OR = 0.35, 95% CI = 0.10-1.20, P = .100). Deep infection rates in the AIBC and control groups were similar when laminar airflow was applied to the operating room (OR = 0.90, 95% CI = 0.60-1.35, P = .620); however, without laminar airflow, the efficacy of AIBC in decreasing deep infection rates was significantly higher than that of control group (OR = 0.21, 95% CI = 0.08-0.59, P = .003).

CONCLUSIONS

AIBC may significantly decrease deep infection rates after primary total hip and knee arthroplasty, with or without systemic antibiotics.

Antibiotic-loaded bone cement is associated with a lower risk of revision following primary cemented total knee arthroplasty: an analysis of 731,214 cases using National Joint Registry data

AIMS

Antibiotic-loaded bone cements (ALBCs) may offer early protection against the formation of bacterial biofilm after joint arthroplasty. Use in hip arthroplasty is widely accepted, but there is a lack of evidence in total knee arthroplasty (TKA). The objective of this study was to evaluate the use of ALBC in a large population of TKA patients.

MATERIALS AND METHODS

Data from the National Joint Registry (NJR) of England and Wales were obtained for all primary cemented TKAs between March 2003 and July 2016. Patient, implant, and surgical variables were analyzed. Cox proportional hazards models were used to assess the influence of ALBC on risk of revision. Body mass index (BMI) data were available in a subset of patients.

RESULTS

Of 731 214 TKAs, 15 295 (2.1%) were implanted with plain cement and 715 919 (97.9%) with ALBC. There were 13 391 revisions; 2391 were performed for infection. After adjusting for other variables, ALBC had a significantly lower risk of revision for any cause (hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.77 to 0.93; p < 0.001). ALBC was associated with a lower risk of revision for all aseptic causes (HR 0.85, 95% CI 0.77 to 0.95; p < 0.001) and revisions for infection (HR 0.84, 95% CI 0.67 to 1.01; p = 0.06). The results were similar when BMI was added into the model, and in a subanalysis where surgeons using only ALBC over the entire study period were excluded. Prosthesis survival at ten years for TKAs implanted with ALBC was 96.3% (95% CI 96.3 to 96.4) compared with 95.5% (95% CI 95.0 to 95.9) in those implanted with plain cement. On a population level, where 100 000 TKAs are performed annually, this difference represents 870 fewer revisions at ten years in the ALBC group.

CONCLUSION

After adjusting for a range of variables, ALBC was associated with a significantly lower risk of revision in this registry-based study of an entire nation of primary cemented knee arthroplasties. Using ALBC does not appear to increase midterm implant failure rates. Cite this article: Bone Joint J 2019;101-B:1331-1347.

Implant Engineering in the Age of Biologics

Implants and their technological advances have been a critical component of musculoskeletal care for almost a century. Modern implants are designed to enhance bone ingrowth, promote soft-tissue healing, and prevent infection. Porous metals and short-stem fixation devices have rendered previously unreconstructable bony deficits reconstructable. Stem cells, growth factors, and novel biocompatible compounds have been designed to promote and enhance soft tissue attachment to implants. Antimicrobial modifications have been engineered onto implants to deter bacterial attachment, and innovative surface modifications and eluting technologies may be in our near future. Yet, given the enormous economic pressures in orthopaedics, marketing claims of innovation often exceed scientific accomplishment. Vigilance is thus required in distinguishing transformational discovery from unsubstantiated claims.

Antibiotic-Loaded Polymethylmethacrylate Beads and Spacers in Treatment of Orthopedic Infections and the Role of Biofilm Formation

Polymethylmethacrylate (PMMA) also referred as (acrylic) bone cement is a non-degradable biomaterial that has been used in clinical orthopedic practice for several decades. PMMA can be used in a plain formulation, but is often used in an antibiotic-loaded formulation in (primary and revision) arthroplasty and in treatment of orthopedic infections as prosthetic joint infections (PJI) and chronic osteomyelitis. In treatment of PJIs antibiotic-loaded PMMA is often used as a carrier material for local antibiotic delivery in addition to treatment with systemic antibiotics. In this case, the antibiotic-loaded PMMA is often used as a spacer or as a bead chain. Since the introduction of PMMA as an antibiotic carrier there is a tremendous amount of scientific and clinical papers published, which studied numerous different aspects of antibiotic-loaded PMMA. This paper will review the research regarding basic principles of antibiotic-loaded PMMA as mechanism of action, antibiotic-release capacities, choice of antibiotics and influences on mechanical properties of PMMA. Subsequently, concerns regarding the application of antibiotic-loaded PMMA, biofilm formation, antibiotic resistance and local or systemic toxicity will be discussed. In addition to these subjects, the role of antibiotic loaded PMMA in clinical treatment of PJIs and chronic osteomyelitis is discussed in the final part of this paper.

Influence of Fixation Methods on Prosthetic Joint Infection Following Primary Total Knee Replacement: Meta-Analysis of Observational Cohort and Randomised Intervention Studies

The type of fixation used in primary total knee replacement (TKR) may influence the risk of prosthetic joint infection (PJI). We conducted a systematic review and meta-analysis to assess published evidence linking type of fixation (cemented, uncemented, or hybrid) with the risk of PJI following primary TKR. Randomised controlled trials (RCTs) and observational cohort studies comparing fixation methods and reporting PJI incidence following primary TKR were identified in MEDLINE, Embase, Web of Science, and Cochrane Library up until November 2018. Summary measures were relative risks (RR) with 95% confidence intervals (CIs). We identified 32 eligible articles (24 observational studies and 8 RCTs) involving 1,161,292 TKRs. In pooled analysis of observational studies, uncemented fixation was associated with a decreased overall PJI risk when compared with cemented fixation at 0.76 (0.64–0.89). Comparing antibiotic-loaded cemented fixation with plain cement, there was no significant difference in overall PJI risk at 0.95 (0.69–1.31), but PJI risk was increased in the first 6-month postoperative period to 1.65 (1.12–2.43). Limited data from RCTs showed no differences in PJI risk among the fixation types. Observational evidence suggests uncemented fixation may be associated with lower PJI risk in primary TKR when compared with cemented fixation. In the early postoperative period, antibiotic-loaded cemented fixation may be associated with increased PJI risk when compared with plain cement. This may either reflect appropriate selection of higher risk patients for the development of PJI to cemented and antibiotic-loaded cement or may reflect a lower PJI risk in uncemented TKR due to factors such as shorter operative time.

Does the Use of Antibiotic-Loaded Bone Cement Have an Effect on Deep Infection in Primary Total Knee Arthroplasty Practice?

BACKGROUND

Total knee arthroplasty (TKA) is performed to improve the quality of life by reducing knee arthralgia. One of the most destructive and expensive complications of TKA is deep infection. The primary purpose of this study was to evaluate the effect of using antibiotic-loaded bone cement (ALBC) on the incidence of deep infection after primary TKA.

PATIENTS AND METHODS

A total of 506 patients who underwent primary knee arthroplasty at the Antalya Training and Research Hospital between February 2009 and January 2016 were investigated retrospectively.

RESULTS

The ALBC was used for 85 patients (16.7%), who constituted group 1. Plain bone cement was used for 421 patients (83.2%), who constituted group 2. Deep infection was observed in one patient (1.1%) in group 1 and in six patients (1.4%) in group 2, a difference that is not statistically significant. On average, the deep infection occurred six months after the surgery at the earliest and 19 months at the latest.

CONCLUSION

Use of ALBC did not decrease the incidence of deep infection in TKA. Therefore, we prefer bone cement without any antibiotic.

Routine use of commercial antibiotic-loaded bone cement in primary total joint arthroplasty: a critical analysis of the current evidence

Antibiotic-loaded cement (ABLC) has been widely utilized as an adjuvant treatment for patients with periprosthetic joint infection (PJI) but has also evolved to play a prophylactic role against infection in primary total joint arthroplasties (TJA). Nevertheless, there is currently a paucity of studies that systematically investigated this concept. This review aimed at answering the following questions: (I) Can routine use of ABLC help reduce the current infection rates in primary TJA? (II) What are the risks associated with this approach? And (III) can routine use be justified in primary TJA from an economic standpoint? Multiple databases were queried including PubMed, EMBASE, EBSCO Host, and SCOPUS. Studies published between January 1, 1990 and March 31, 2018 were reviewed. Inclusion criteria were studies reporting: (I) clinical outcomes of routine use of ABLC in primary hip and knee arthroplasty with 2-year minimum follow-up, (II) complications related to the use of ABLC, (III) cost of using ABLC. The final analysis included 24 studies. Data from multiple studies demonstrate contradictory results for infection rates when ABLC is used in all primary procedures with a majority of studies showing similar infection rates between ABLC and plain cement. The main concerns associated with routine use of ABLC are negative effects on the mechanical stability of cement, possible systemic and local toxicity of the absorbed antibiotic, and development of resistant bacterial strains. However, current literature has not clinically validated these concerns. Lastly, with an estimated increase in 117 million dollars with the routine use of ABLC in only 50% of TJAs performed each year, it is difficult to justify the use of ABLC without clear superiority in reducing infection. The use of ABLC has undeniably changed the way orthopaedic surgeons deal with PJI today. However, the large-scale, prophylactic use of ABLC in primary TJAs requires further research and justification.

The Hidden Cost of Commercial Antibiotic-Loaded Bone Cement: A Systematic Review of Clinical Results and Cost Implications Following Total Knee Arthroplasty

BACKGROUND

The purpose of this systematic review is to compare deep prosthetic joint infections (PJIs) between total knee arthroplasty (TKA) patients treated with either antibiotic-loaded bone cement (ALBC) or plain bone cement, and to explore the potential cost implications of commonly used bone cement regimens. We hypothesized that ALBC would not substantially reduce PJIs and would thereby present an unnecessary cost to the healthcare system.

METHODS

Using the PRISMA guidelines, we reviewed articles through May 2017 involving primary TKA patients with both ALBC cohort and plain bone cement cohort. A meta-analysis was performed comparing the prevalence of deep infections between cohorts. A cost comparison for a hypothetical setting with an annual volume of 1000 TKAs was performed to compare 3 commonly used cement regimens: 2 bags of ALBC used during each case, 1 bag of ALBC with 1 bag of plain cement, and 2 bags of plain cement. Pricing at our institution is $215/bag for commercial ALBC and $60/bag for plain cement.

RESULTS

Eight articles were included with a total of 34,664 patients. ALBC did not reduce the PJI (ALBC = 93/8189, 1.1% vs plain = 251/26,475, 0.9%; P = .09). The estimated costs for the 3 bone cement regimens per 1000 primary TKAs were as follows: 2 bags of ALBC = $430,000/y, 1 bag of ALBC +1 bag of plain cement = $275,000/y, and 2 bags of plain cement = $120,000/y.

CONCLUSION

ALBC did not reduce the prevalence of PJI suggesting that ALBC may be an unnecessary cost to the healthcare system. Hospital systems that perform 1000 TKAs/y could save between $155,000 and $310,000/y by switching to plain cement.

Antibiotic-laden Bone Cement in Primary and Revision Hip and Knee Arthroplasty

Antibiotic-laden bone cement (ALBC) has a number of different uses in primary and revision total joint arthroplasty. However, considerable controversy remains regarding how and when it is best used. The prophylactic use of low-dose ALBC in primary cemented total hip arthroplasty is well supported by the literature, conferring both clinical and economic benefits. In contrast, conclusive evidence on the clinical efficacy or economic benefit of the routine use of ALBC in primary total knee arthroplasty remains elusive. Given the currently available evidence, we cannot determine definitively whether the routine use of ALBC in primary total knee arthroplasty is justified, although selective use in patients with a high risk of infection seems warranted. The routine use of ALBC in revision total joint arthroplasty is well accepted, with good supporting evidence in studies of both aseptic and first-stage revision procedures. Although limited clinical evidence exists on the use of ALBC at the time of definitive component reimplantation after septic revision, the rationale for its use is strong.

Reconstructive Science in Orthopedic Oncology

Limb salvage is widely practiced as standard of care in most cases of extremity bone sarcoma. Allograft and endoprosthesis reconstructions are the most widely utilized modalities for the reconstruction of large segment defects, however complication rates remain high. Aseptic loosening and infection remain the most common modes of failure. Implant integration, soft-tissue function, and infection prevention are crucial for implant longevity and function. Macro and micro alterations in implant design are reviewed in this manuscript. Tissue engineering principles using nanoparticles, cell-based, and biological augments have been utilized to develop implant coatings that improve osseointegration and decrease infection. Similar techniques have been used to improve the interaction between soft tissues and implants. Tissue engineered constructs (TEC) used in combination with, or in place of, traditional reconstructive techniques may represent the next major advancement in orthopaedic oncology reconstructive science, although preclinical results have yet to achieve durable translation to the bedside.

Antibiotic-loaded Bone Cement as Prophylaxis in Total Joint Replacement

One of its most serious complications associated with arthroplasty is the development of infections. Although its prevalence is only between 0.5% and 3%, in some cases it can lead to death. Therefore, an important challenge in joint surgery is the prevention of infections when an arthroplasty is performed. The use of antibiotic-loaded cements could be a suitable tool due to numerous advantages. The main advantage of the use of antibiotic loading into bone cement derives directly from antibiotic release in the effect site, allowing achievement of high concentrations at the site of action, and minimal or no systemic toxicity. This route of administration was first described by Buchholz and Engelbrecht. In the case of infection treatment, this is an established method and its good results have been confirmed. However, its role in infection prevention, and, therefore, the use of these systems in clinical practice, has proved controversial because of the uncertainty about the development of possible antibiotic resistance after prolonged exposure time, their effectiveness, the cost of the systems, toxicity and loosening of mechanical properties. This review discusses all these topics, focusing on effectiveness and safety, antibiotic decisions, cement type, mixing method, release kinetics and future perspectives. The final objective is to provide the orthopaedic surgeons the right information in their clinical practice based on current evidence.

Prosthetic Joint Infections: an Update

PURPOSE OF REVIEW

Prosthetic joint infection (PJI) is a rare but serious complication that is frequently misdiagnosed. We aimed to highlight the nuances of PJI diagnosis and antimicrobial therapies and provide clarity in key areas of management.

RECENT FINDINGS

Current research in PJI centers on a potential role for diagnostic biomarkers, molecular techniques, and implant sonication to reduce culture-negativity rates. The optimal duration of antimicrobial therapy remains controversial. A high clinical index of suspicion for PJI combined with data from multiple preoperative and intraoperative tests enables timely diagnosis and treatment. Biomarkers, molecular methods, and implant sonication are currently adjunctive to traditional diagnostic techniques. Shorter courses of antimicrobial therapies as well as the role of chronic suppressive therapy need confirmation by randomized controlled trials. Existing practices for preoperative dental prophylaxis and treatment of asymptomatic bacteriuria warrant revision based on evidence arguing against risk for PJI.