State-of-the-art diagnosis and surgical treatment of acute peri-prosthetic joint infection following primary total hip arthroplasty

Current updates in MSK infection imaging: A narrative review

This article presents a comprehensive overview of the diagnostic utility of existing imaging techniques including radiography, computed tomography, ultrasonography, magnetic resonance imaging (MRI), and radionuclide imaging in the context of the most common orthopaedic or musculoskeletal infections. It also includes illustrative images showcasing significant findings in various musculoskeletal infections including osteomyelitis, cellulitis, septic arthritis, necrotising infections and peri-prosthetic joint infections and their associated complications.

Articulating Hip Spacers with a Constrained Acetabular Liner: Effect of Acetabular Bone Loss and Cementation Quality

Articulating hip spacers for periprosthetic joint infection (PJI) offer numerous advantages over static spacers such as improved patient mobilization, hip functionality, and soft tissue tension. Our study aimed to determine complication rates of a functional articulating spacer using a constrained liner to determine the role of acetabular cementation mantle and bone loss on the need for second-stage surgery. A retrospective review of 103 patients was performed and demographic information, spacer components and longevity, spacer-related complications, reinfection rates, and grade of bone loss and acetabular cement mantle quality were determined. There was no significant difference in spacer-related complications or reinfection rate between PJI and native hip infections. 33 of 103 patients (32.0%) elected to retain their spacers. Between patients who retained their initial spacer and those who underwent reimplantation surgery, there was not a significant difference in cement mantle grade (p = 0.52) or degree of bone loss (p = 0.78). Functional articulating antibiotic spacers with cemented constrained acetabular liners demonstrate promising early results in the treatment of periprosthetic and native hip infections. The rate of dislocation events was low. Further efforts to improve cement fixation may help decrease the need for second-stage reimplantation surgery.

Influence of Addition of Antibiotics on Chemical and Surface Properties of Sol-Gel Coatings

Infection is one of the most common causes that leads to joint prosthesis failure. In the present work, biodegradable sol-gel coatings were investigated as a promising controlled release of antibiotics for the local prevention of infection in joint prostheses. Accordingly, a sol-gel formulation was designed to be tested as a carrier for 8 different individually loaded antimicrobials. Sols were prepared from a mixture of MAPTMS and TMOS silanes, tris(tri-methylsilyl)phosphite, and the corresponding antimicrobial. In order to study the cross-linking and surface of the coatings, a battery of examinations (Fourier-transform infrared spectroscopy, solid-state ²⁹Si-NMR spectroscopy, thermogravimetric analysis, SEM, EDS, AFM, and water contact angle, thickness, and roughness measurements) were conducted on the formulations loaded with Cefoxitin and Linezolid. A formulation loaded with both antibiotics was also explored. Results showed that the coatings had a microscale roughness attributed to the accumulation of antibiotics and organophosphites in the surface protrusions and that the existence of chemical bonds between antibiotics and the siloxane network was not evidenced.

The use of an antibacterial implant in the treatment of periprosthetic infection in an HIV-positive patient

Background: The frequency of occurrence of infectious complications after hip arthroplasty in HIV-infected patients is extremely high. Revision arthroplasty for periprosthetic infection is the leader (64%) among the causes of early revision interventions. The search for ways to increase the efficiency of the sanitizing stage of treatment due to antibacterial coatings of the endoprosthesis components continues.

Objective: Demonstration of a clinical case of treatment of periprosthetic infection in an HIV-positive patient using a spacer and a femoral component of a hip joint endoprosthesis coated with linear Sp1 carbon chains and silver. 123 months after hip arthroplasty for stage 3 dysplastic coxarthrosis in HIV-positive patient of 42 years old developed an instability of the acetabular component with the growth of Staphylococcus aureus in punctates. A revision was performed with the removal of the endoprosthesis and the installation of an articulating spacer with the addition of antibiotics. 12 weeks later, a recurrence of periprosthetic infection occurred, and Enterococcus faecalis was detected in punctates. During re-endoprosthetics, there was an installation of an articulating spacer covered with a two-dimensionally ordered linear-chain carbon doped with silver, based on the Zimmer CPT femoral component and bone cement with antibiotics addition. After 3 months, the second stage of revision arthroplasty was performed with implantation of an individual acetabular component and a femoral component coated with two-dimensionally ordered linear-chain carbon doped with silver.

Conclusion: 4 months after the operation the patient returned to work, 12 months later the functional results were satisfactory. The use of components coated with two-dimensionally ordered linear-chain carbon doped with silver in an HIV-positive patient with recurrent periprosthetic infection made it possible to stop the infectious process, improve limb function and the quality of life.

The use of an antibacterial implant in the treatment of periprosthetic infection in an HIV-positive patient

Background: The frequency of occurrence of infectious complications after hip arthroplasty in HIV-infected patients is extremely high. Revision arthroplasty for periprosthetic infection is the leader (64%) among the causes of early revision interventions. The search for ways to increase the efficiency of the sanitizing stage of treatment due to antibacterial coatings of the endoprosthesis components continues.

Objective: Demonstration of a clinical case of treatment of periprosthetic infection in an HIV-positive patient using a spacer and a femoral component of a hip joint endoprosthesis coated with linear Sp1 carbon chains and silver. 123 months after hip arthroplasty for stage 3 dysplastic coxarthrosis in HIV-positive patient of 42 years old developed an instability of the acetabular component with the growth of Staphylococcus aureus in punctates. A revision was performed with the removal of the endoprosthesis and the installation of an articulating spacer with the addition of antibiotics. 12 weeks later, a recurrence of periprosthetic infection occurred, and Enterococcus faecalis was detected in punctates. During re-endoprosthetics, there was an installation of an articulating spacer covered with a two-dimensionally ordered linear-chain carbon doped with silver, based on the Zimmer CPT femoral component and bone cement with antibiotics addition. After 3 months, the second stage of revision arthroplasty was performed with implantation of an individual acetabular component and a femoral component coated with two-dimensionally ordered linear-chain carbon doped with silver.

Conclusion: 4 months after the operation the patient returned to work, 12 months later the functional results were satisfactory. The use of components coated with two-dimensionally ordered linear-chain carbon doped with silver in an HIV-positive patient with recurrent periprosthetic infection made it possible to stop the infectious process, improve limb function and the quality of life.

[Experimental study of silkworm larvae plasma colorimetry based on immune cascade reaction in accurate diagnosis of periprosthetic joint infection]

OBJECTIVE

To investigate the diagnostic efficacy of silkworm larvae plasma (SLP) colorimetry in the accurate diagnosis of periprosthetic joint infection (PJI).

METHODS

Ninety healthy male New Zealand white rabbits were used for knee arthroplasty with Swanson prosthesis. Then they were randomly divided into 3 groups according to different pathogenic bacteria: group A ( Staphylococcus aureus group), group B ( Staphylococcus epidermidis group) and group C ( Escherichia coli group), with 30 rats in each group. The PJI model was prepared by knee injection with 1 mL of pathogenic bacteria of different concentrations. Samples were taken before inoculation and at 7, 14, and 21 days after inoculation, and based on the 2018 PJI Philadelphia International Consensus diagnostic criteria, the success rate of modeling among 3 groups of experimental animals was determined. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic efficiency of SLP colorimetry were calculated.

RESULTS

At 21 days after inoculation, 26, 18, and 23 rabbits in groups A, B, and C were diagnosed as infection, respectively. The success rates of modeling were 86.7%, 60.0%, and 76.7%, respectively, showing no significant difference among the 3 groups ( χ ²=5.724, P=0.073). The results of PJI colorimetry showed that 1 false-positive animal (specificity 75.0%) appeared in group A at 7 days, and the specificity of SLP increased to 100.0% over time (on 14 and 21 days); on 14 and 21 days, another animal appeared false-negative results (sensitivity decreased from 100.0% to 96.2%). One false-positive animal appeared in group B at 7 days (specificity 91.7%), the specificity returned to 100.0% over time; 1 and 4 false-negative animals appeared at 14 and 21 days, respectively (sensitivity 94.4% and 83.3%, respectively). In group C, two false-positive animals (specificity 71.4%) were found at 7 days, and then returned to 100.0%. The diagnostic efficiency of groups A and C was very high at 21 days (96.7% and 100.0%), even for the low virulence Staphylococcus epidermidis in group B, the diagnostic efficiency could be maintained at 90.0% (21 days), and the overall diagnostic efficiency was very good (95.6%).

CONCLUSION

SLP colorimetry has high sensitivity, specificity, and diagnostic efficiency in the diagnosis of PJI, which is a potential diagnostic method.

SdrG gene activated joint surface membrane protein PTPRJ to induce periprosthetic joint infection after total hip arthroplasty

WHAT IS KNOWN AND OBJECTIVE

Up to now, no study focused on the role of SdrG in PJI after THA. To explore the mechanism of periprosthetic joint infection (PJI) after total hip arthroplasty (THA).

METHODS

Joint fluid and blood were collected from patients with PJI after THA, aseptic loosening of the joints or bacterial infection after traumatic fractures of the extremities alone. The expression of SdrG in the 3 groups was determined by agarose gel electrophoresis. The expression of protein tyrosine phosphatase receptor J (PTPRJ) was measured by immunohistochemistry method. The platelet adhesion rate was determined by biochemical analysis. The content of D-dimer, CRP and ESR in blood was determined by latex agglutination method. Multiple linear correlation analysis was used to analyse the correlation between PJI and the expression of PTPRJ protein, platelet adhesion rate, D-dimer content, CRP and ESR.

RESULTS AND DISCUSSION

The expression of SdrG and PTPRJ in PJI group was markedly increased compared to the other 2 groups. The platelet adhesion rate in PJI group was markedly larger compared to aseptic loosening and simple wound infection group, and the rate in simple wound infection group was larger than aseptic loosening group. The level of D-dimer, CRP and ESR in PJI group was higher than that of the other groups. The expression of PTPRJ protein, D-dimer content, CRP and ESR was all closely related to PJI, while platelet adhesion rate had no correlation with PJI.

WHAT IS NEW AND CONCLUSION

SDRG gene around joint prosthesis was over-expressed, which activated joint surface membrane protein PTPRJ and then induced platelet aggregation to reduce joint function.

Management strategies for prosthetic joint infection: long-term infection control rates, overall survival rates, functional and quality of life outcomes

DAIR (debridement, antibiotics, and implant retention), one-stage and two-stage revision surgery are the most common management strategies for prosthetic joint infection (PJI) management. Our knowledge concerning their efficacy is based on short to medium-term low-quality studies.

Most studies report infection recurrence rates or infection-free time intervals. However, long-term survival rates of the infection-free joints, functional and quality of life outcome data are of paramount importance.

DAIR, one-stage and two-stage revision strategies are not unique surgical techniques, presenting several variables. Infection control rates for the above strategies vary from 75% to 90%, but comparisons are difficult because different indications and patient selection criteria are used in each strategy.

Recent outcome data show that DAIR and one-stage revision in selected patients (based on host, bacteriological, soft tissue and type of infection criteria) may present improved functional and quality of life outcomes and reduced costs for health systems as compared to those of two-stage revision.

It is expected that health system administrators and providers will apply pressure on surgeons and departments towards the wider use of DAIR and one-stage revision strategies. It is the orthopaedic surgeon’s responsibility to conduct quality studies in order to fully clarify the indications and outcomes of the different revision strategies.

Cite this article: EFORT Open Rev 2021;6:727-734. DOI: 10.1302/2058-5241.6.210008

Analysis of Culture Positive First and Second Stage Procedures in Periprosthetic Knee and Hip Joint Infections

BACKGROUND

A positive microbiological result at reimplantation may lead to a failed 2-stage revision arthroplasty in the treatment of periprosthetic joint infections. Little is known about changes in microbiological spectrum and resistance pattern between culture positive first and second stage procedures in revision knee and hip arthroplasty.

METHODS

Between January 2011 and December 2019, we performed 327 two-stage revision arthroplasties on 312 patients. There were 37 of 312 (11.9%) patients (20 hips/17 knees) who had a positive microbiological culture during the first and second stage procedure. We analyzed the microbiological spectrum, antimicrobial resistance pattern, and clinical outcome of culture positive first and second stage procedures as well as subsequent re-revisions.

RESULTS

Re-revision was necessary in 40.5% (15/37) of patients with culture positive first and second stage procedure at a median follow-up of 3.5 years. We found microbiological changes in 83.8% (31/37) of patients between the first and second stage and in 88.9% (8/9) between the second stage and subsequent culture positive re-revision. Polymicrobial infections were found in 21.6% (8/37) of first and in 16.2% (6/37) of second stage procedures. In 27% (10/37) of patients, microorganisms persisted between the first and second stage procedure. The antimicrobial resistance pattern changed in 60% of persistent microorganisms between the first and second stage procedure.

CONCLUSION

Changes in microbiological spectrum and resistance pattern are common between culture positive first and second stage procedures as well as subsequent re-revisions. This has to be considered in the antimicrobial treatment of periprosthetic joint infections.

Time-dependent efficacy of combination of silver-containing hydroxyapatite coating and vancomycin on methicillin-resistant Staphylococcus aureus biofilm formation in vitro

OBJECTIVE

We developed a silver-containing hydroxyapatite (Ag-HA) coating to prevent periprosthetic joint infection (PJI). Methicillin-resistant Staphylococcus aureus (MRSA) is the main PJI-causing bacteria. Previously, we had reported the combined effect of Ag-HA coating and vancomycin (VCM) on MRSA biofilm formation 24 h after MRSA inoculation. In this study, we investigated the time-dependent efficacy of Ag-HA coating and VCM on MRSA biofilm formation on Ti discs in vitro by three-dimensional confocal laser scanning microscopic analysis.

RESULTS

For the Ti VCM and HA VCM groups, the total biofilm volumes per area at 96 h after MRSA inoculation were significantly larger than those at 48 h after MRSA inoculation, respectively (p < 0.001). In contrast, for the Ag-HA VCM group, the total biofilm volume per area at 96 h was significantly smaller than that at 48 h (p < 0.0001). Moreover, 96 h after MRSA inoculation, the total biofilm volume per area of the Ag-HA VCM groups was significantly smaller than those of the Ti VCM and HA VCM groups (p < 0.0001). Thus, the combination of Ag-HA and VCM might be useful for the prevention of MRSA-associated PJI.

Dair approach in 7 infected total hip arthroplasties: our experience and current concepts of the literature

INTRODUCTION

Periprosthetic joint infection (PJI) is one of the most challenging complications following total hip arthroplasty. In early infection, within four to twelve weeks from surgery, debridement, antibiotics and implant retention (DAIR) can be the initial treatment. The aim of this study is to report our case series and review current concepts reported in the literature about this topic.

MATERIALS AND METHODS

This was an observational cohort study that included 7 patients managed with DAIR for PJI following primary total hip replacement (THR) between 2014 and 2020. Inclusion criteria were a primary THR, direct anterior or lateral approach, DAIR procedure, and PJI. Exclusion criteria were a PJI following a revision total hip replacement or hemiarthroplasty, posterolateral approach, 1-stage revision, 2-stage revision, and Girdlestone procedure without prior DAIR. For each patient demographic characteristics, laboratory values, microorganisms involved, antibiotic therapy and outcome at one-year follow-up were registered.

RESULTS

The mean duration between THR and DAIR was 19 days. In all cases only one DAIR procedure was performed. Most infections were caused by Staphylococcus aureus (4 cases) [one methicillin resistant (MRSA)]. The other infections were caused by Streptococcus agalactiae, Staphylococcus coagulase negative and Escherichia coli. At the final follow-up, the procedure was considered as successful in 6 out of 7 patients (85%). The one with unsuccessful outcome underwent to a two-stage revision.

DISCUSSION

Our results were comparable with those of a recent systematic review of the literature. Factors that have been postulated to influence the outcome of DAIR in the management of PJIs include the timing and numbers of debridement, the exchange of components, the responsible microorganism and the duration of antibiotic treatment. In conclusion, the outcomes following DAIR are better as the indications are refined and risk factors identified. PJI prevention remains the key but the current literature still lacks well documented and effective PJI prevention protocols. (www.actabiomedica.it).

Debridement, Antibiotics, and Implant Retention with the Direct Anterior Approach for Acute Periprosthetic Joint Infection Following Primary THA

Background:

Periprosthetic joint infection (PJI) is a devastating complication following total hip replacement. The direct anterior approach for total hip replacement is becoming increasingly popular. However, little is known about the success rate of treatment with debridement, antibiotics, and implant retention (DAIR) using the direct anterior approach. The aim of this study was to analyze the effectiveness of DAIR using this approach and identify patient and surgical factors that influence the results.

Methods:

Seventy-four patients (75 hips) in whom DAIR had been performed were identified from the records of the weekly multidisciplinary infection meeting and the laboratory information management systems. In 4% (3 hips), modular components were exchanged. To consider competing risks (death), we used competing risk models.

Results:

The competing risk analysis showed a successful outcome after DAIR of 82% at 4 years of follow-up; this rate was 89% at 4 years follow-up when excluding patients managed with gentamicin beads. The sensitivity analysis revealed that obesity (body mass index [BMI] of ≥30 kg/m²), use of gentamicin beads, and an erythrocyte sedimentation rate (ESR) of >40 mm/hr increased the risk of failure.

Conclusions:

DAIR using the direct anterior approach without the routine exchange of modular components offers a success rate that is comparable with other approaches for eradicating acute PJI following primary hip arthroplasty.

Level of Evidence:

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

Prosthetic joint infections: clinical management, diagnosis, and treatment

PURPOSE OF REVIEW

Prosthetic joint infections (PJIs) represent one of the most disastrous complications in prosthetic surgery, requiring long hospitalization, prolonged antimicrobial treatment and repeated surgical interventions. No gold standard test to formulate diagnosis exist. A combination of high index of suspicion, physical examination, microbiological and biohumoral investigations is required. Therapeutical approach should be based on a multidisciplinary team. In our center, a two-stage approach is preferred. As regards the choice of the empirical antibiotic backbone, individual risk factors for multiple-drug resistant (MDR) pathogens should be considered. Several studies enhance the possibility to shorten the length of antibiotic couses.

RECENT FINDINGS

Some interesting improvements have been made in the setting of PJIs management. As regards diagnosis, novel biomarkers and nuclear imaging are acquiring more importance. Molecular biology techniques also offer the possibility to formulate rapid microbiological identification. The pattern of PJIs is evolving towards higher rates of MDR causes. During the last decade, a number of new antibiotic molecules with activity against MDRs have been approved. Some of them are also available either in oral formulation or as long-acting compounds, offering the opportunity for early patient's discharge, with expected healthcare costs saving.

SUMMARY

Management of PJIs still represents a major threat for clinicians. Improvements in surgical techniques and antibiotic pipeline promise to revolutionize the approach in next years. Despite data from our experience confirm the efficacy of shorter antibiotic courses and the value of new molecules, randomized clinical trials are lacking. More data are needed in order to modify the routine clinical practice.

Loosening of total knee arthroplasty - always aseptic?

PURPOSE

When revision surgery is needed in total knee arthroplasty (TKA) the most frequent reasons are aseptic loosening (AL) and periprosthetic joint infection (PJI). However preoperative distinction between AL and PJI remains challenging. Aim of this study is to determine the incidence of PJI in patients with suspected AL after TKA and to evaluate a diagnostic algorithm for reliable differential diagnosis.

METHODS

In this study a total of 149 symptomatic patients with radiographic signs of prosthetic loosening and suspected AL were included. Preoperatively all patients underwent a standardized diagnostic algorithm. For each patient demographics, as well as the results of laboratory and microbiological testing were collected from the medical records.

RESULTS

Of the included patients 117 (78.5%) were diagnosed with AL and 32 (21.5%) with PJI. The latency period from primary arthroplasty to the presentation with symptomatic implant loosening was significantly shorter for PJI compared to AL (p < 0.05). The initial CRP values were significantly higher in patients with PJI compared to patients with AL (p < 0.05). Elevated count of white blood cells or percentage of neutrophils within the synovial fluid support the diagnosis of PJI. The sensitivity of synovial cell count (CC) count for PJI in patients with radiographic signs of loosening was 0.84 (CI 0.81-0.87) with a specificity of 0.96 (CI 0.92-0.98). The single best measure for the diagnosis of PJI was synovial fluid cultures with a specificity of 1, however this measure provides poor sensitivity.

CONCLUSION

Patients with radiographic signs of loosening in TKA need thorough diagnostics. Information about primary TKA, serological testing, and results of joint aspiration can rule out a PJI in most cases.