Imaging modalities demonstrate moderate and heterogeneous diagnostic accuracy for periprosthetic joint infection: A systematic review and meta‐analysis
Abstract Purpose The diagnostic accuracy of imaging modalities in periprosthetic joint infections (PJIs) remains uncertain. This study assessed and compared the performance of different imaging techniques for diagnosing PJI. Methods A systematic review and meta‐analysis of studies published in PubMed and Embase (1 January 2000 to 1 March 2024) was conducted. Eligible studies included adults (≥18 years), applied a valid reference standard for PJI diagnosis, and provided sufficient data to construct 2 × 2 contingency tables. Imaging modalities included white blood cell scintigraphy (WBCS), FDG‐PET/CT, antigranulocyte scintigraphy (AGS), bone scintigraphy (BS), magnetic resonance imaging (MRI), computed tomography (CT) and related combinations. Risk of bias was assessed using the QUADAS‐2 tool. A bivariate random‐effects model estimated pooled diagnostic odds ratios, sensitivities, and specificities with 95% confidence intervals (CIs). Results Forty studies (1263 PJI cases, 4700 controls) were included. Pooled sensitivity and specificity were as follows: WBCS‐SPECT/CT: 87.1% (95% CI, 31.7–99.0) and 94.1% (95% CI, 87.5–97.3); WBCS‐BMS: 79.7% (95% CI, 58.3–91.7) and 94.2% (95% CI, 91.0–96.3); WBCS: 88.1% (95% CI, 73.8–95.1) and 80.0% (95% CI, 62.2–90.7); FDG‐PET (±PET/CT): 88.1% (95% CI, 79.9–93.2) and 87.2% (95% CI, 76.3–93.5); BS‐WBCS: 59.5% (95% CI, 43.2–73.9) and 96.6% (95% CI, 92.2–98.6); BS: 89.3% (95% CI, 80.9–94.2) and 74.1% (95% CI, 59.0–85.0); AGS: 89.1% (95% CI, 76.8–95.3) and 73.0% (95% CI, 63.1–81.0). No eligible studies were identified for MRI or CT. Substantial heterogeneity was observed. Conclusion Diagnostic performance varied substantially, and no modality consistently demonstrated superior accuracy. WBCS showed the most stable results, particularly when combined with BS or BMS. Given the heterogeneity and variability in specificity, imaging should complement comprehensive diagnostic evaluation rather than be used in isolation. Level of Evidence 2a–3a, systematic review and meta‐analysis of retrospective cohort and case‐control studies.
Microbial next generation DNA sequencing of aspirated synovial fluid shows concordance with ICM criteria biomarkers for diagnosing periprosthetic joint infection in hip and knee arthroplasty
Background The diagnosis of periprosthetic joint infection (PJI) is facilitated by consensus identification of synovial biomarkers, which may be aided by targeted microbial next generation sequencing (NGS) of synovial fluid. The primary objective of the study was to evaluate NGS performance across 3 years to ICM 2018 minor criteria for PJI. Methods Synovial fluid specimens submitted from 2020–2022 by outpatient surgical clinics to MicroGenDX for matched synovial biomarker and NGS analysis were selected for retrospective analysis. Synovial biomarkers tested included C-reactive protein (CRP), white blood cell (WBC) count, and polymorphonuclear (PMN) leukocyte percentage. Synovial fluid analysis compared NGS microbial positivity with positive incidence of PJI determined by scoring of synovial biomarkers using ICM 2018 minor criteria for infection. Results The overall sensitivity, specificity, and accuracy of NGS to ICM diagnosed PJI across 2,011 specimens was 76.4% [95% CI, 0.723–0.801], 92.3% [0.91–0.94], and 88.7% [0.87–0.90], respectively. When comparing the diagnostic performance of NGS and individual biomarkers to infection, NGS was more specific to PJI than synovial CRP (specificity = 0.894, 95% CI: 0.88–0.91), but not PMN or WBC. NGS was positive in 7.7% of ICM negative samples. NGS positive: ICM negative samples were associated with significantly elevated synovial PMN ( p = 0.001) and WBC ( p < 0.0001) compared to NGS negative: ICM negative samples. Across all samples, NGS positivity was associated with significantly elevated results for all tested biomarkers ( p < 0.0001). Eight bacterial species dominated the composition in 68% of samples, whereas 46 different microbes were dominant in the remaining third. Conclusion Microbial targeted NGS positivity was concordant with ICM minor criteria for PJI and should be considered a useful tool for diagnosis. There is a low risk of false positive detections comparable to ICM biomarkers. Elevated biomarkers in NGS positive: ICM negative samples may indicate infection occurring that is poorly captured by the three measured synovial biomarkers. Uncommon species are collectively common to PJI and NGS is uniquely positioned to detect such species as they are frequently missed by conventional microbiological testing, including culture and quantitative PCR. These results suggest formal diagnostic schemes would benefit from the addition of NGS as a diagnostic criterion.
One-Stage Versus Two-Stage Exchange Arthroplasty for Periprosthetic Joint Infection
Background: A 2-stage approach is most commonly used to treat periprosthetic joint infection (PJI). Some successful studies of the 1-stage approach were underpowered, lacked a 2-stage comparative group, and excluded patients with draining sinuses, comorbidities, and/or antibiotic-resistant organisms. Given the morbidity and expense associated with 2-stage treatment, we conducted a prospective, multicenter, randomized trial to compare the results of 1- and 2-stage PJI treatment, specifically including patients with draining sinuses, comorbidities, and resistant organisms. Methods: Patients presenting for surgical treatment of a chronic PJI with a known organism following primary total hip or knee arthroplasty were included (with infection defined by Musculoskeletal Infection Society [MSIS] criteria). Patients with prior revision, culture-negative infection, or fungal infection, or who were immunosuppressed or had soft-tissue involvement precluding wound closure, were excluded. Patients were classified according to the McPherson host staging system. Clinical success was defined as (1) no clinical failure or reinfection with the same or new organism; (2) no reoperation for PJI; and (3) no PJI-related death. A double-instrument setup was used for all patients, as were similar irrigation and antibiotic protocols. A total of 323 patients (166 one-stage; 157 two-stage) were randomized. Groups were similar with respect to demographics and host classification. After excluding patients who died or were lost to follow-up, 258 of the 323 patients had 2-year follow-up (135 one-stage and 123 two-stage). The rate of patient loss to follow-up was similar between the treatment groups. Results: Sixteen patients in the 1-stage group and 9 patients in the 2-stage group died prior to 2-year follow-up. Overall, the 2-year success rate of 1-stage treatment was 97% (131 of 135), while the success of 2-stage treatment was 91% (112 of 123) (p = 0.04). Compared with the 2-stage group, the 1-stage group had 3-times the odds of overall success in a regression analysis (unadjusted odds ratio = 3.22 [95% confidence interval = 1.0 to 10.38]). After adjusting for specific variables (McPherson host grade, resistant organism, and draining sinuses), 1-stage treatment also had 3-times the odds of success. Conclusions: The results of this prospective randomized trial indicated that 1-stage treatment (97% success) was statistically noninferior to 2-stage treatment (91% success) when treating chronic PJI following primary total hip or knee arthroplasty, provided the protocols described here are explicitly followed. Extrapolation to other patient cohorts and clinical situations should be avoided. Level of Evidence: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.
2025 International Consensus Meeting on Musculoskeletal Infection: Summary From the Biofilm Workgroup on Biofilm Formation, Persistence, and Host‐Environment Interactions
ABSTRACT Musculoskeletal infection (MSKI) remains a major problem after trauma and elective orthopedic surgery. Chronic MSKI is related to the formation of biofilm, which impairs diagnosis and effective treatments. Therefore, to understand and communicate global standards and best practices, the 2025 International Consensus Meeting (ICM) on MSKI created a Biofilm Section to address crucial aspects of biofilm biology pertaining to its mechanisms of drug resistance and immune evasion, and potential approaches to overcome them. This featured a 2‐year process, with final voting and discussion on May 8–10, 2025, in Istanbul, Turkey. This Consensus Article is the effort of the Biofilm Basic Mechanisms Workgroup, which interpreted the results on ICM questions related to (1) the infectious microenvironment; (2) appropriate inocula in preclinical research; (3) biofilm behavior in infected tissues; and (4) synergy within biofilms and with other comorbidities. Collectively, we find that this field has the necessary research tools to discover the pathophysiology of orthopedic implant‐associated biofilm development and maturation, perform clinically relevant studies in animal models, and elucidate mechanisms that allow opportunistic infections in compromised tissues and patients with other health issues.
OPTIMIZING PERIPROSTHETIC JOINT INFECTION DIAGNOSTICS: THE IMPACT OF INTRAOPERATIVE DIRECT SONICATION ON TIME TO POSITIVITY
AimThis study aimed to evaluate the impact of intraoperative direct sonication on the yield of traditional culture and the time to positivity (TTP) of cultures obtained for periprosthetic joint infection (PJI), thereby assessing its potential to improve diagnostic efficiency and reduce contamination risk.MethodA prospective cohort study was conducted at a tertiary care center, involving 190 patients undergoing revision surgery for PJI from August 2021 to January 2024. Patients were included based on the 2018 International Consensus Meeting definition of PJI. The study utilized a novel sonication protocol, which involved direct intraoperative sonication of the implant and tissue, followed by incubation in a BACT/ALERT 3D system. The primary outcomes measured were the number and percentage of positive culture samples, identified microorganisms, and the TTP of each culture. Statistical analysis was performed using R software, with various tests applied to assess the significance of findings.ResultsThe study included 510 positive cultures from 190 patients, demonstrating that sonication significantly improved the positivity rate for both tissue and prosthesis specimens (p < 0.05). The median TTP for all samples was 3.13 days, with sonicated samples showing a significantly shorter TTP compared to non-sonicated samples (p < 0.05). Specifically, the shortest median TTP was observed in prosthesis post-sonication samples. Furthermore, the study found that Gram-positive organisms had a shorter TTP than gram-negative organisms, and specific microorganisms like Staphylococcus aureus and MRSE showed the fastest TTP. The analysis also revealed higher positivity rates in chronic PJIs compared to acute PJIs for sonicated tissue samples.ConclusionsThe study demonstrates that intraoperative direct sonication combined with the BACT/ALERT 3D system can significantly enhance the diagnostic yield of cultures and reduce the TTP for common PJI pathogens. This novel technique not only improves pathogen detection, facilitating the tailoring of antibiotic therapy, but also potentially reduces the risk of contamination associated with sonication. These findings suggest that direct intraoperative sonication could be a valuable addition to the current diagnostic protocols for PJI, contributing to more effective management and treatment of this complex condition. Further research is necessary to explore the clinical significance of TTP and its correlation with patient outcomes in PJI.
Peripheral nerve block anesthesia/analgesia for patients undergoing primary hip and knee arthroplasty: recommendations from the International Consensus on Anesthesia-Related Outcomes after Surgery (ICAROS) group based on a systematic review and meta-analys
Background Evidence-based international expert consensus regarding the impact of peripheral nerve block (PNB) use in total hip/knee arthroplasty surgery. Methods A systematic review and meta-analysis: randomized controlled and observational studies investigating the impact of PNB utilization on major complications, including mortality, cardiac, pulmonary, gastrointestinal, renal, thromboembolic, neurologic, infectious, and bleeding complications. Medline, PubMed, Embase, and Cochrane Library including Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, were queried from 1946 to August 4, 2020. The Grading of Recommendations Assessment, Development, and Evaluation approach was used to assess evidence quality and for the development of recommendations. Results Analysis of 122 studies revealed that PNB use (compared with no use) was associated with lower ORs for (OR with 95% CIs) for numerous complications (total hip and knee arthroplasties (THA/TKA), respectively): cognitive dysfunction (OR 0.30, 95% CI 0.17 to 0.53/OR 0.52, 95% CI 0.34 to 0.80), respiratory failure (OR 0.36, 95% CI 0.17 to 0.74/OR 0.37, 95% CI 0.18 to 0.75), cardiac complications (OR 0.84, 95% CI 0.76 to 0.93/OR 0.83, 95% CI 0.79 to 0.86), surgical site infections (OR 0.55 95% CI 0.47 to 0.64/OR 0.86 95% CI 0.80 to 0.91), thromboembolism (OR 0.74, 95% CI 0.58 to 0.96/OR 0.90, 95% CI 0.84 to 0.96) and blood transfusion (OR 0.84, 95% CI 0.83 to 0.86/OR 0.91, 95% CI 0.90 to 0.92). Conclusions Based on the current body of evidence, the consensus group recommends PNB use in THA/TKA for improved outcomes. Recommendation: PNB use is recommended for patients undergoing THA and TKA except when contraindications preclude their use. Furthermore, the alignment of provider skills and practice location resources needs to be ensured. Evidence level: moderate; recommendation: strong.
Definition of Successful Infection Management and Guidelines for Reporting of Outcomes After Surgical Treatment of Periprosthetic Joint Infection
ABSTRACT Musculoskeletal infections (MSKI) remain the bane of orthopedic surgery, and result in grievous illness and inordinate costs that threaten healthcare systems. As prevention, diagnosis, and treatment has remained largely unchanged over the last 50 years, a 2nd International Consensus Meeting on Musculoskeletal Infection (ICM 2018, https://icmphilly.com ) was completed. Questions pertaining to all areas of MSKI were extensively researched to prepare recommendations, which were discussed and voted on by the delegates using the Delphi methodology. The questions, including the General Assembly (GA) results, have been published ( GA questions ). However, as critical outcomes include: (i) incidence and cost data that substantiate the problems, and (ii) establishment of research priorities; an ICM 2018 research workgroup (RW) was assembled to accomplish these tasks. Here, we present the result of the RW consensus on the current and projected incidence of infection, and the costs per patient, for all orthopedic subspecialties, which range from 0.1% to 30%, and $17,000 to $150,000. The RW also identified the most important research questions. The Delphi methodology was utilized to initially derive four objective criteria to define a subset of the 164 GA questions that are high priority for future research. Thirty‐eight questions (23% of all GA questions) achieved the requisite > 70% agreement vote, and are highlighted in this Consensus article within six thematic categories: acute versus chronic infection, host immunity, antibiotics, diagnosis, research caveats, and modifiable factors. Finally, the RW emphasizes that without appropriate funding to address these high priority research questions, a 3rd ICM on MSKI to address similar issues at greater cost is inevitable.
A Trans-Atlantic Perspective on Stagnation in Clinical Translation of Antimicrobial Strategies for the Control of Biomaterial-Implant-Associated Infection