Treatment Of Periprosthetic Joint Infection Research Articles

New bone cements with Pluronic®F127 for prophylaxis and treatment of periprosthetic joint infections

In line with the increase in orthopedic prosthetic surgeries, there has been a significant rise in periprosthetic joint infections (PJI) due to Methicillin-Resistant Staphylococcus Aureus (MRSA) bacteria. In case of infection, antibiotic-added spacers are temporarily placed into the periprosthetic region. With the release of antibiotics usually failing to work in fighting off infection, recent studies have centered around developing more effective approaches. New polymethylmethacrylate (PMMA) cement mixtures were prepared for this study with Pluronic®F127, bicarbonate, and citric acid addition. Optimal solutions were searched by monitoring vancomycin release on consecutive days with HPLC in in-vitro. The strengths of the samples were measured via four-point bending tests. Compared to conventional PMMA, strength values were observed to have improved by about 20% with 1.0 g of Pluronic®F127. According to HPLC studies, the highest increase for the area under the curve value was obtained for Pluronic®F127 doped mixture with a value of about 20%. It is understood from SEM and BET studies that addition of Pluronic®F127 helps increase porosity. The present study concludes that the optimum concentration of Pluronic®F127 could improve the strength and drug-releasing capacity of the spacer by increasing its porosity.

Total Femur Antibiotic Spacers: Effective Salvage for Complex Periprosthetic Joint Infections

BackgroundA simultaneous periprosthetic joint infection (PJI) of an ipsilateral hip and knee arthroplasty is a challenging complication of lower extremity reconstructive surgery. We evaluated the use of total femur antibiotic-impregnated polymethylmethacrylate (PMMA) bone cement spacers in the staged treatment of such limb-threatening PJIs. MethodsThirteen patients were treated with a total femur antibiotic spacer. The mean age at the time of spacer placement was 65 years. Nine patients had polymicrobial PJIs. All spacers incorporated vancomycin (3.0 g/40 g PMMA) and gentamicin (3.6 g/40 g PMMA), while 8 also included amphotericin (150 mg/40 g PMMA). Eleven spacers were biarticular. Twelve spacers were implanted through one longitudinal incision, while 8 of 12 reimplantations occurred through 2 smaller, separate hip and knee incisions. Mean follow-up after reimplantation was 3 years. ResultsTwelve (92%) patients underwent reimplantation of a total femur prosthesis at a mean of 26 weeks. One patient died of medical complications 41 days after spacer placement. At latest follow-up, 3 patients had experienced PJI recurrence managed with irrigation and debridement. One required acetabular component revision for instability. All 12 reimplanted patients retained the total femur prosthesis with no amputations. Eleven (91%) were ambulatory, and 7 (58%) remained on suppressive antibiotics. ConclusionTotal femur antibiotic spacers are a viable, but technically demanding, limb-salvage option for complex PJIs involving the ipsilateral hip and knee. In the largest series to date, there were no amputations and 75% of reimplanted patients remained infection-free. Radical debridement, antimicrobial diversity, prolonged spacer retention, and limiting recurrent soft tissue violation are potential tenets of success. Level of EvidenceIV.

Restoration of the hip geometry after two-stage exchange with intermediate resection arthroplasty for periprosthetic joint infection

Two-stage exchange with intermediate resection arthroplasty (RA) is a well-established surgical procedure in the treatment of chronic periprosthetic joint infection (PJI), whereby a higher failure rate of final hip geometry restoration due to tissue contraction is controversially discussed. The aim was to evaluate radiographic changes of hip geometry parameters during PJI treatment and to determine the impact of the intermediate RA on the final joint restoration after reimplantation of a total hip arthroplasty (reTHA). Radiographic parameters (leg length (LL), femoral offset (FO), horizontal/vertical acetabular center of rotation distance (h/vCORD)) of 47 patients (mean age: 64.1 years) were measured on standard radiographs of the pelvis and compared between four different stages during PJI treatment (pre-replacement status (preTHA), primary total hip arthroplasty (pTHA), RA and reTHA). The RA duration (mean: 10.9 months) and the number of reoperations during this period (mean: n = 2.0) as well as their impact on hip geometry restoration were evaluated. Between preTHA and pTHA/reTHA an equivalent restoration was measured regarding the FO (p < 0.001/p < 0.001) and hCORD (p = 0.016/p < 0.001), but not regarding the LL and vCORD. In contrast, analysis revealed no influence of RA and an equivalent reconstruction of LL (p = 0.003), FO (p < 0.001), v/hCORD (p = 0.039/p = 0.035) at reTHA compared to pTHA. Furthermore, RA duration (p = 0.053) and the number of reoperations after RA (p = 0.134) had no impact on radiographic hip geometry restoration. The two-stage exchange with intermediate RA does not alter the preexisting hip joint parameters, whereby a good restoration of the final hip geometry, independent of the duration or the number of reoperations, can be achieved.

External Validation Demonstrates Limited Clinical Utility of a Preoperative Prognostic Calculator for Periprosthetic Joint Infection

BackgroundPreoperative calculation of treatment failure risk in patients undergoing surgery for periprosthetic joint infection (PJI) is imperative to allow for medical optimization and targeted prevention. A preoperative prognostic model for PJI treatment failure was previously developed, and this study sought to externally validate the model. MethodsA retrospective review was performed of 380 PJIs treated at two institutions. The model was used to calculate the risk of treatment failure, and receiver operating characteristic curves were generated to calculate the area under the curve (AUC) for each institution. ResultsWhen applying this model to institution 1, an AUC of 0.795 (95% confidence interval [CI]: 0.693-0.897) was found, whereas institution 2 had an AUC of 0.592 (95% CI: 0.502-0.683). Comparing all institutions in which the model had been applied to, we found institution 2 represented a significantly sicker population and different infection profile. ConclusionIn this cohort study, we externally validated the prior published model for institution 1. However, institution 2 had a decreased AUC using the prior model and represented a sicker and less homogenous cohort compared with institution 1. When matching for chronicity of the infection, the AUC of the model was not affected. This study highlights the impact of comorbidities and their distributions on PJI prognosis and brings to question the clinical utility of the algorithm which requires further external validation.

39800 Immune Checkpoint Blockade during Periprosthetic Joint Infection

ABSTRACT IMPACT: If immune checkpoint blockade increases bacterial clearance with or without antibiotics in vitro, clinical application would be almost immediate and dramatic creating a seismic shift in the current therapeutic paradigm of periprosthetic joint infection. OBJECTIVES/GOALS: Periprosthetic joint infection (PJI) is a major cause of failure after joint replacement. Currently, the treatment of PJI relies on removing biofilm contaminated implants. Some of the bacteria within biofilm undergo a phenotypic shift becoming small colony variants (SCVs). SCVs induce local immunosuppression through PD-1/L1 signaling. METHODS/STUDY POPULATION: We will infect cultured human macrophages and bone marrow aspirate with stable Staphylococcus aureus SVCs and treat with anti-PD-1 or anti-PD-L1 monoclonal antibodies with and without antibiotics (e.g., gentamycin, cefazolin, vancomycin, rifampicin) and assess the residual bacterial viability. We will utilize multiplexed ion beam imaging to quantify PD-1/L1 expression in human tissue from patients with a chronic PJI and compare those to patients undergoing an aseptic revision. Patients with a chronic PJI are likely to have increased expression of PD-1/L1 as their tissue samples are prospectively screened. RESULTS/ANTICIPATED RESULTS: SCVs reduce the phagocytic activity of macrophages and can survive intracellularly. SCVs also induce anti-inflammatory M2-macrophage polarization and recruit a heterogeneous group of immature monocytes and granulocytes called myeloid-derived suppressor cells (MDSC) to the periprosthetic microenvironment. M2-macrophages and MDSCs then produce an immunosuppressive cytokine milieu characterized by increased IL-10 and decreased TNF-α. Clinically isolated SCVs up-regulate the expression of PD-L1 and PD-L2 on the surface of macrophages, representing a mechanism by which SCVs induce host immunosuppression and survive immune clearance. Our preliminary data show PD-L1 expression during septic PJI, but not in aseptic revisions. DISCUSSION/SIGNIFICANCE OF FINDINGS: If immune checkpoint blockade is shown to increase bacterial clearance with or without antibiotics, host immunomodulation would represent a novel class of therapeutic adjuvants to assist surgical debridement and antibiotic administration that could be superimposed on existing treatment algorithms to improve PJI related outcomes.

Two-Stage Reimplantation of a Prosthetic Hip Infection: Systematic Review of Long-Term Reinfection and Pathogen Outcomes

BackgroundAlthough two-stage exchange for chronic periprosthetic hip infections remains an effective option for infection eradication, long-term outcome reporting remains scarce. Compiling outcomes data for this standard of care is necessary to characterize long-term reinfection risk and identify bacteria associated with reinfection. The purpose of our study was to perform a systematic review to determine the long-term risk of reinfection after two-stage reimplantation. The second purpose was to identify the proportion of reinfections caused by the same or different organism(s) relative to the index infection. MethodsWe performed a systematic review of two-stage reimplantation randomized control trials, cohort studies, and case series for the treatment of periprosthetic joint infections, yielding 320 unique citations for abstract review, of which 138 were reviewed in full. We collected reinfection data including the timing of reinfection after successful reimplantation and the bacteria identified at reinfection. Meeting inclusion criteria were 28 studies with 2047 patients and 2055 hips that completed both reimplantation stages with just seven studies having greater than 24 month follow-up. ResultsStudies with longer average follow-up reported significantly higher all-time reinfection rates (P = .042). Among studies with at least 5 years of follow-up, the risk of reinfection was 10.25% (8.21-12.47). Among studies with minimum follow-up of at least 24 months, the 24-month rate of reinfection was 4.58% (2.17-7.66), which increased to 7.34% (4.44-10.82) by final follow-up. Only 12 studies reported index and recurrent pathogen data. In those studies, 3.00% (1.19-5.38) of all hips which completed both reimplantation stages were reinfected by a new pathogen, and 1.70% (0.52-3.35) of patients became reinfected by recurrent pathogens. ConclusionWhile the majority of two stage reimplantation literature follows patients for two years, there is significant risk of reinfection into the long term. Further studies with detailed outcomes and long-term follow-up are needed to identify factors associated with late infections.

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

BackgroundA 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. MethodsBetween 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. ResultsRe-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. ConclusionChanges 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.

Effectiveness of topical adjuvants in reducing biofilm formation on orthopedic implants: an invitro analysis.

The treatment of periprosthetic joint infection is complicated by the presence of residual biofilm, which resists eradication owing to bacterial adherence to orthopedic implants. The purpose of this study was to compare Bactisure (Zimmer Biomet, Warsaw, IN, USA), povidone-iodine (Betadine), and chlorhexidine gluconate solution (Irrisept; Irrimax, Gainesville, FL, USA) in reducing biofilm formation of Staphylococcus aureus, Staphylococcus epidermidis, and Cutibacterium acnes inoculated on cobalt-chrome, titanium, and stainless steel disks, representing metals commonly used for shoulder arthroplasty. The hypothesis was that there would be no significant difference in biofilm reduction among the 3 topical adjuvants. Strains of S aureus (ATCC 35556), S epidermidis (ATCC 35984), and C acnes (LMG 16711) were grown on cobalt-chrome, titanium, and stainless steel disks. For each strain, the disks were divided into 4 groups: (1) control, (2) povidone-iodine (Betadine), (3) chlorhexidine gluconate (Irrisept), and (4) Bactisure. Bacteria were grown on 5% sheep blood agar plates. Biofilm eradication was quantified using adenosine triphosphate bioluminescence and compared with controls 48 and 72 hours after implementation of the topical adjuvant. At 72 hours after implementation of the topical adjuvant, a statistically significant reduction in colony-forming units was observed for all topical adjuvants across all tested metals, as compared with their respective control. With respect to the topical adjuvants themselves, Bactisure more consistently demonstrated the most significant reduction in colony-forming units across all bacteria when the tested medium was adjusted for, with the exception of S aureus, which showed similar results to Betadine at 72 hours. By use of commonly encountered topical adjuvants on S aureus-, S epidermidis-, and C acnes-inoculated disks of various implant metals, a significant reduction in biofilm production was observed. Bactisure, a recent Food and Drug Administration-approved topical adjuvant, demonstrated the overall greatest efficacy of the agents studied.

Use of antibiotic-impregnated hydroxyapatite for infection following total knee arthroplasty

Objectives Antibiotic-impregnated hydroxyapatite (HA) is an emerging drug delivery system for the treatment of periprosthetic joint infection (PJI) of the knee. The aim of this study was to evaluate the clinical results of this treatment in patients with PJI following total knee arthroplasty (TKA). Methods Participants comprised 14 consecutive patients with PJI of the knee who were scheduled to undergo two-stage knee revision. In the first stage, all components were removed with thorough debridement, and antibiotic-impregnated HA was inserted in the bone and joint space. In the second stage, revision TKA was performed after the eradication of infection. The mean period from the removal of all components and treatment with antibiotic-impregnated HA to revision TKA was 3.4 months. Clinical and radiographic evaluations were performed after a mean follow-up of 6.1 years following revision TKA. Predictors of reinfection were evaluated. Results Eleven patients had no recurrent infection, whereas 3 patients showed recurrent infection. Knee Society knee score and function score, as well as flexion angles, improved significantly postoperatively. No knees showed osteolysis or loosening after revision TKA. The present study identified no predictors of reinfection. Conclusion Antibiotic-impregnated HA could be effective in treating knee PJI.

Randomized Trial of Static and Articulating Spacers for Treatment of the Infected Total Hip Arthroplasty

BackgroundThe purpose of this randomized clinical trial is to compare perioperative and postoperative variables between static and articulating spacers for the treatment of chronic periprosthetic joint infection (PJI) complicating total hip arthroplasty (THA). MethodsFifty-two patients undergoing resection arthroplasty as part of a 2-stage exchange for PJI at 3 centers were randomized to either a static (n = 23) or articulating spacer (n = 29). The primary endpoint was operative time of the second-stage reimplantation and power analysis determined that 22 patients per cohort were necessary to detect a 20-minute difference. Seven patients were lost to follow-up, 4 were never reimplanted, and one died before discharge after reimplantation. Forty patients were followed for a mean 3.2 years (range 2.0-7.1). ResultsThere were no differences in operative time at second-stage reimplantation (143 minutes static vs 145 minutes articulating, P = .499). Length of hospital stay was longer in the static cohort after stage 1 (8.6 vs 5.4 days, P = .006) and stage 2 (6.3 vs 3.6 days, P < .001). Although it did not reach statistical significance with the numbers available for study, nearly twice as many patients in the static cohort were discharged to an extended care facility after stage 1 (65% vs 30%, P = .056). ConclusionThis randomized trial demonstrated that the outcomes of static and articulating spacers are similar in the treatment of THA PJI undergoing 2-stage exchange arthroplasty. The significantly longer length of hospital stay associated with the use of static spacers may have important economic implications for the health care system.

Comparing the Efficacy of Articulating Spacer Constructs for Knee Periprosthetic Joint Infection Eradication: All-Cement vs Real-Component Spacers

BackgroundThe most common treatment for periprosthetic joint infection (PJI) after total knee arthroplasty (TKA) is a 2-stage revision. Few studies have compared different articulating spacer constructs. This study compares the outcomes of real-component and all-cement articulating spacers for TKA PJI treatment. MethodsThis retrospective observational study examined the arthroplasty database at 3 academic hospitals for articulating spacers placed for TKA PJIs between April 2011 and August 2020. Patients were categorized as receiving a real-component or an all-cement articulating spacer. Data on demographics, surgical information, and outcomes were collected. ResultsOne-hundred sixty-four spacers were identified: 72 all-cement and 92 real-component spacers. Patients who received real-component spacers were older (67 ± 10 vs 63 ± 12 years; P = .04) and more likely to be former smokers (50.0% vs 28.6%; P = .02). Real-component spacers had greater range of motion (ROM) after Stage 1 (84° ± 28° vs 58° ± 28°; P < .01) and shorter hospital stays after Stage 1 (5.8 ± 4.3 vs 8.4 ± 6.8 days; P < .01). There was no difference in time to reimplantation, change in ROM from pre-Stage 1 to most recent follow-up, or reinfection. Real-component spacers had shorter hospital stays (3.3 ± 1.7 vs 5.4 ± 4.9 days; P < .01) and operative times during Stage 2 (162.2 ± 47.5 vs 188.0 ± 66.0 minutes; P = .01). ConclusionReal-component spacers had improved ROM after Stage 1 and lower blood loss, shorter operative time, and shorter hospital stays after Stage 2 compared to all-cement articulating spacers. The 2 spacer constructs had the same ultimate change in ROM and no difference in reinfection rates, indicating that both articulating spacer types may be safe and effective options for 2-stage revision TKA. Level of EvidenceIII, retrospective observational analysis.

Progress in Prevention, Diagnosis, and Treatment of Periprosthetic Joint Infection.

Periprosthetic joint infection (PJI) after joint replacement surgery is a severe complication associated with high morbidity and increased treatment costs. More than 25% of joint implant failures are attributed to PJI. PJI diagnosis and treatment methods have substantially improved in recent years. However, the prevalence of PJI remains high, primarily due to the increased prevalences of obesity, diabetes, and other underlying conditions. Moreover, increasing elderly prefers to total joint replacement surgery. However, due to frailty and comorbidities, most are at increased risk of infectious arthritis and artificial joint infection (PJI). Therefore, PJI management for the elderly requires multilevel and multiangle intervention. In this review, we summarize the risk factors and diagnostic methods currently available for PJI and discuss the current PJI prevention and treatment interventions, especially the management in older adults.

One-stage revision is as effective as two-stage revision for chronic culture-negative periprosthetic joint infection after total hip and knee arthroplasty.

Removal of infected components and culture-directed antibiotics are important for the successful treatment of chronic periprosthetic joint infection (PJI). However, as many as 27% of chronic PJI patients yield negative culture results. Although culture negativity has been thought of as a contraindication to one-stage revision, data supporting this assertion are limited. The aim of our study was to report on the clinical outcomes for one-stage and two-stage exchange arthroplasty performed in patients with chronic culture-negative PJI. A total of 105 consecutive patients who underwent revision arthroplasty for chronic culture-negative PJI were retrospectively evaluated. One-stage revision arthroplasty was performed in 30 patients, while 75 patients underwent two-stage exchange, with a minimum of one year's follow-up. Reinfection, re-revision for septic and aseptic reasons, amputation, readmission, mortality, and length of stay were compared between the two treatment strategies. The patient demographic characteristics did not differ significantly between the groups. At a mean follow-up of 4.2 years, the treatment failure for reinfection for one-stage and two-stage revision was five (16.7%) and 15 patients (20.0%) (p = 0.691), and for septic re-revision was four (13.3%) and 11 patients (14.7%) (p = 0.863), respectively. No significant differences were observed between one-stage and two-stage revision for 30- 60- and 90-day readmissions (10.0% vs 8.0%; p = 0.714; 16.7% vs 9.3%; p = 0.325; and 26.7% vs 10.7%; p = 0.074), one-year mortality (3.3% vs 4.0%; p > 0.999), and amputation (3.3% vs 1.3%; p = 0.496). In this non-randomized study, one-stage revision arthroplasty demonstrated similar outcomes including reinfection, re-revision, and readmission rates for the treatment of chronic culture-negative PJI after TKA and THA compared to two-stage revision. This suggests culture negativity may not be a contraindication to one-stage revision arthroplasty for chronic culture-negative PJI in selected patients. Cite this article: Bone Joint J2021;103-B(3):515-521.

The Double DAIR: A 2-Stage Debridement with Prosthesis-Retention Protocol for Acute Periprosthetic Joint Infections.

Debridement and implant retention (DAIR) has variable success as a treatment for acute periprosthetic joint infection (PJI), with generally poor outcomes reported in the literature1. Because of the unacceptably high failure rate of DAIR, we implemented a 2-stage debridement protocol that includes the use of high-dose antibiotic beads between stages for the treatment of acute PJI. In 2 previous studies, with an average follow-up of 3.5 years in each study, we reported overall infection-control rates of 87% and 90%2,3. Following exposure of the joint, cultures are obtained, and all modular components are removed, scrubbed, and soaked in an antiseptic solution. A thorough irrigation and debridement with complete synovectomy is performed, followed by temporary reinsertion of the original modular parts. High-dose antibiotic cement beads are inserted into the joint, and the joint is closed. Approximately 5 to 6 days later, a second debridement is performed, the beads are removed, and the new modular, sterile components are implanted. The patient is placed on a course of intravenous and, later, oral antibiotics, in addition to a standard postoperative rehabilitation protocol. Long-term suppressive antibiotic therapy.One-stage DAIR.One-stage exchange arthroplasty.Two-stage exchange arthroplasty.Resection arthroplasty.Amputation. The treatment of acute PJI has historically consisted of a single irrigation and debridement, with exchange of modular parts and retention of the components, followed by intravenous antibiotic therapy. Despite having lower rates of patient morbidity compared with a 2-stage exchange arthroplasty, this more traditional procedure also has a higher rate of failure, with reported rates as high as 60% to 84%4-12. The utility of component retention continues to be a topic of debate13. Alternatives to component retention include both 1- and 2-stage exchange procedures. Although these modalities offer potentially higher rates of infection control, they are associated with substantial patient morbidity, particularly in patients with well-fixed implants14-16. Furthermore, exchange procedures may result in substantial iatrogenic bone loss, which can be problematic in revision total joint arthroplasty procedures, in which bone stock may already be limited. The double-DAIR protocol offers infection-control rates that are comparable with those of component-exchange procedures, but with the lower patient morbidity associated with component-retention procedures. Furthermore, the double-DAIR procedure provides the added benefit of retaining important bone stock. The success rate for the double-DAIR procedure has been reproducible, with infection-control rates of 87% and 90% reported in 2 studies from a single cohort at our institution2,3. These rates represent a substantial improvement compared with a single irrigation and debridement1, and are on par with those reported for 2-stage exchange arthroplasty procedures17-21. The infection-control rates of the double-DAIR procedure did not significantly vary depending on whether infection occurred following a total knee or total hip arthroplasty. However, not surprisingly, patients who underwent debridement following a revision procedure had a lower rate of success (77.1% successful infection control) compared with patients debrided following a primary procedure (93.8% successful infection control). We could not demonstrate an association with organism and success or failure of treatment.Although not significant, there was a trend toward an association between the time from symptom onset to initial treatment and infection control (p = 0.07)2. Patients with successful infection control underwent the initial debridement an average of 6.2 days after symptom onset, compared with 10.7 days in patients in whom treatment had failed. Several other studies have demonstrated that successful infection control is associated with earlier initial irrigation and debridement22-27. We strongly support that, in the setting of confirmed acute PJI, prompt initiation of treatment optimizes the chances for successful infection control. Thorough debridement is key to successful infection control of infection.Antibiotic-loaded bone cement has repeatedly been demonstrated to be safe, and we recommend its use28-31.Extended oral antibiotics following debridement with component retention can increase infection-free survivorship32.

Comparison of outcomes between static spacers versus articulating spacers in the setting of revision periprosthetic knee infections: a systematic review

Background: Two-stage exchange arthroplasty is the standard of care treatment for periprosthetic joint infection (PJI) of knee in the United States. This procedure involves implantation of antibiotic-loaded spacer in order to eradicate the infection prior to reimplantation of the prosthesis. While traditionally static spacer was used in interim period between explantation and reimplantation, articulating spacer has become the spacer of choice recently. The purpose of this review is to describe differences in surgical techniques, and clinical outcomes (complications, reinfections) between static and articulating spacers.

Successful Two-Stage Exchange Arthroplasty for Periprosthetic Infection Following Total Knee Arthroplasty: The Impact of Timing on Eradication of Infection.

Background: Periprosthetic joint infection (PJI) represents a serious complication following total knee arthroplasty. In the setting of chronic infections, the two-staged approach has traditionally been the preferred treatment method. The aim of this study was to determine the optimal period of rest between the first and second stage. Furthermore, we analyzed potentially outcome-relevant parameters, such as general and local conditions and the presence of difficult-to-treat or unidentified microorganisms, with regard to their impact on successful treatment of PJI.Patients and Methods: We performed a retrospective analysis of prospectively collected data for all patients treated for PJI at our institution. Seventy-seven patients who had undergone two-stage revision arthroplasty for PJI of the knee were included into the study. Antibiotic-loaded cement spacers were used for all patients.Results: After a median follow-up time of 24.5 months, infection had reoccurred in 14 (18.7%) patients. A prolonged spacer-retention period of more than 83 days was related to a significantly higher proportion of reinfections. Furthermore, significant compromising local conditions of the prosthetic tissue and surrounding skin, as well as repeated spacer-exchanges between first- and second-stage surgery, negatively influenced the outcome. Neither the patients' age nor gender exerted a significant influence on the outcome regarding reinfection rates for patients' age or gender.Conclusions: We observed the best outcome regarding infection control in patients who had undergone second-stage surgery within 12 weeks after first-stage surgery. Nearly 90% of these patients stayed free from infection until the final follow-up. An increased number of performed spacer-exchanges and a bad local extremity grade also had a negative impact on the outcome.

Blood and synovial fluid calprotectin as biomarkers to diagnose chronic hip and knee periprosthetic joint infections.

Calprotectin (CLP) is produced in neutrophils and monocytes and released into body fluids as a result of inflammation or infection. The aim of this study was to evaluate the utility of blood and synovial CLP in the diagnosis of chronic periprosthetic joint infection (PJI). Blood and synovial fluid samples were collected prospectively from 195 patients undergoing primary or revision hip and knee arthroplasty. Patients were divided into five groups: 1) primary total hip and knee arthroplasty performed due to idiopathic osteoarthritis (OA; n = 60); 2) revision hip and knee arthroplasty performed due to aseptic failure of the implant (AR-TJR; n = 40); 3) patients with a confirmed diagnosis of chronic PJI awaiting surgery (n = 45); 4) patients who have finished the first stage of the PJI treatment with the use of cemented spacer and were qualified for replantation procedure (SR-TJR; n = 25), and 5) patients with rheumatoid arthritis undergoing primary total hip and knee arthroplasty (RA; n = 25). CLP concentrations were measured quantitatively in the blood and synovial fluid using an immunoturbidimetric assay. Additionally, blood and synovial CRP, blood interleukin-6 (IL-6), and ESR were measured, and a leucocyte esterase (LE) strip test was performed. Patients with PJI had higher CLP concentrations than those undergoing aseptic revision in blood (median PJI 2.14 mg/l (interquartile range (IQR) 1.37 to 3.56) vs AR-TJR 0.66 mg/l (IQR 0.3 to 0.83); p < 0.001) and synovial fluid samples (median PJI 20.46 mg/l (IQR 14.3 to 22.36) vs AR-TJR 0.7 mg/l (IQR 0.41 to 0.95); p < 0.001). With a cut-off value of 1.0 mg/l, blood CLP showed a sensitivity, specificity, positive predictive value, and negative predictive value of 93.3%, 87.5%, 89.4%, and 92.1%, respectively. For synovial fluid with a cut-off value of 1.5 mg/l, these were 95.6%, 95%, 95.5%, and 95%, respectively. This small study suggests that synovial and blood CLP are useful markers in chronic PJI diagnosis with similar or higher sensitivity and specificity than routinely used markers such as CRP, ESR, IL-6, and LE. CLP was not useful to differentiate patients with PJI from those with rheumatoid arthritis. Cite this article: Bone Joint J 2021;103-B(1):46-55.

The Impact of Surgical Strategy and Rifampin on Treatment Outcome in Cutibacterium Periprosthetic Joint Infections.

Cutibacterium species are common pathogens in periprosthetic joint infections (PJI). These infections are often treated with β-lactams or clindamycin as monotherapy, or in combination with rifampin. Clinical evidence supporting the value of adding rifampin for treatment of Cutibacterium PJI is lacking. In this multicenter retrospective study, we evaluated patients with Cutibacterium PJI and a minimal follow-up of 12 months. The primary endpoint was clinical success, defined by the absence of infection relapse or new infection. We used Fisher's exact tests and Cox proportional hazards models to analyze the effect of rifampin and other factors on clinical success after PJI. We included 187 patients (72.2% male, median age 67 years) with a median follow-up of 36 months. The surgical intervention was a 2-stage exchange in 95 (50.8%), 1-stage exchange in 51 (27.3%), debridement and implant retention (DAIR) in 34 (18.2%), and explantation without reimplantation in 7 (3.7%) patients. Rifampin was included in the antibiotic regimen in 81 (43.3%) cases. Infection relapse occurred in 28 (15.0%), and new infection in 13 (7.0%) cases. In the time-to-event analysis, DAIR (adjusted hazard ratio [HR] = 2.15, P = .03) and antibiotic treatment over 6 weeks (adjusted HR = 0.29, P = .0002) significantly influenced treatment failure. We observed a tentative evidence for a beneficial effect of adding rifampin to the antibiotic treatment-though not statistically significant for treatment failure (adjusted HR = 0.5, P = .07) and not for relapses (adjusted HR = 0.5, P = .10). We conclude that a rifampin combination is not markedly superior in Cutibacterium PJI, but a dedicated prospective multicenter study is needed.

Direct Inpatient Medical Costs of Operative Treatment of Periprosthetic Hip and Knee Infections Are Twofold Higher Than Those of Aseptic Revisions.

Periprosthetic joint infections (PJIs) following total hip arthroplasty (THA) and total knee arthroplasty (TKA) are associated with substantial morbidity. A better understanding of the costs of PJI treatment can inform prevention, treatment, and reimbursement strategies. The purpose of the present study was to describe direct inpatient medical costs associated with the treatment of hip and knee PJI. At a single tertiary care institution, 176 hips and 266 knees that underwent 2-stage revisions for the treatment of PJI from 2009 to 2015 were compared with 1,611 hips and 1,276 knees that underwent revisions for aseptic indications. In addition, 84 hips and 137 knees that underwent irrigation and debridement (I&D) with partial component exchange were compared with 39 hips and 138 knees that underwent partial component exchange for aseptic indications. Line-item details of services billed during hospitalization were retrieved, and standardized direct medical costs were calculated in 2018 inflation-adjusted dollars. The mean direct medical cost of 2-stage revision THA performed for the treatment of PJI was significantly higher than that of aseptic revision THA ($58,369 compared with $22,846, p < 0.001). Similarly, the cost of 2-stage revision TKA performed for the treatment of PJI was significantly higher than that of aseptic revision TKA ($56,900 compared with $24,630, p < 0.001). Even when the total costs of aseptic revisions were doubled for a representative comparison with 2-stage procedures, the costs of PJI procedures were 15% to 28% higher than those of the doubled costs of aseptic revisions (p < 0.001). The mean direct medical cost of I&D procedures for PJI was about twofold higher than of partial component exchange for aseptic indications. The direct medical costs of operative treatment of PJI following THA and TKA are twofold higher than the costs of similar aseptic revisions. The high economic burden of PJI warrants efforts to reduce the incidence of PJI. Reimbursement schemes should account for the high costs of treating PJI in order to ensure sustainable patient care. Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Periprosthetic Joint Infections - An Overview

Periprosthetic Joint Infections - An Overview Abstract. Diagnostics and treatment of periprosthetic joint infections (PJI) is an interdisciplinary challenge. The key for success in the treatment of PJI is a rapid and adequate diagnostic and treatment in close cooperation between the general practitioner (GP), a specialised orthopaedic surgeon and an infectious disease specialist (ID). Acute PJI mostly occur peri- and early postoperative but can occur also lifelong due to haematogenous / lymphogenic seeding of the germs on the prosthesis. Both situations must be considered as an emergency scenario and patients should be transferred to the operating surgeon or even in a specialised centre for further diagnostics and treatment immediately. An acute infection (either < 4 weeks after implantation or < 3 weeks after the onset of symptoms with haematogenous / lymphogenic seeding) can frequently be cured by debridement, antibiotics and implant retention (DAIR) and should be the favoured approach in this scenario. In chronic PJI an interdisciplinary approach with complete exchange of the implant combined with an elaborated antibiotic therapy is always needed. Optimised and targeted diagnostic as well as an interdisciplinary planning of the treatment are mandatory for curing the infection, therefore patients with chronic PJI should be referred to a specialised centre. Surgery alone without adequate antibiotic therapy will mostly result in failure to cure PJI, same is true for exclusive antibiotic therapy without an adequate surgical procedure.