Pathogenesis and management of fracture-related infection

Phage therapy: A novel approach to combat drug-resistant pathogens

Antibiotic-resistant infections, such as those caused by the overuse of antibiotics, have greatly strained healthcare systems. Among them, drug-resistant bacteria ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) are typical and common. Enterococcus faecalis and Escherichia coli are of equal concern. These pathogens often have higher pathogenicity than the same strains, and resistance has reduced treatment options, so new treatment options are needed to address these pathogens. This review analyzes recent studies related to phage therapy for the treatment of bacterial infections in various parts of the human body (e.g., alcoholic liver disease, skin, and soft tissues, respiratory tract, gastrointestinal tract, urinary system, etc.), to better understand the potential role of phage therapy as a non-antibiotic strategy for the treatment of infections caused by drug-resistant bacteria. In addition, this review introduces a series of products related to phage therapy and points out potential research directions for phage therapy in clinical applications. This paper elucidates the basic mechanism of human infection by some drug-resistant bacteria and the therapeutic effect of phage therapy against drug-resistant bacteria. It popularizes the understanding of phage therapy and provides a reference for research on its use for drug-resistant bacterial infections.

Masquelet technique combined with a lantern-mimicking frame system for treatment of a 28-cm infected bone defect: a case report

Introduction

Treatment of large bone defects resulting from acute injury or infection remains challenging. The Masquelet technique is a two-stage procedure for treating bone defects caused by bone tumor resection, infection, or trauma. There are currently no reports of successful repair of ≥28 cm bone defects using the Masquelet technique.

Case presentation

We describe the case of a 55-year-old man with postoperative infection of a femoral fracture and a 28-cm infected bone defect formed after multiple debridement procedures. The Masquelet technique, when coupled with a Lantern-Mimicking Frame System (LMFS), achieved favorable clinical results. The patient could walk normally without crutches 14 months postoperatively and did not experience pain in daily life.

Conclusions

This was the longest bone defect in a single limb currently reported to had been cured in the literature. The Masquelet technique coupled with LMFS achieved favorable clinical results for the treatment of a 28-cm infected bone defect. For extremely large bone defects in a single limb, the length of the defect was not an absolute limiting condition for the indications of Masquelet technique.

A case report of implanted bone displacement after abscess formation

RATIONALE

Implanted bone is a commonly used filling material for bone defects, participating in the formation of new bone. Complications associated with implanted bone include nonunion, infection, etc. Few cases of implanted bone displacement through gravitational abscesses have been reported in the literature. This article aims to improve clinicians' recognition of this phenomenon and discuss preventive measures and treatment strategies for implant-associated infections.

PATIENT CONCERNS

A 7-year-old female patient was admitted to the hospital due to recurrent purulent fluid discharge from the incision site for 3 months following a right hip surgery 4 months ago. Wound secretion culture revealed a methicillin-resistant Staphylococcus aureus infection. The imaging before the first debridement in the external hospital showed that there were 2 high-density shadows around the right femoral greater trochanter, which were implanted bone.

DIAGNOSES

Implant-related infection and chronic osteomyelitis.

INTERVENTIONS

The implant and inflammatory lesions were removed through multiple surgeries and anti-infection treatment.

OUTCOMES

After 6 months of follow-up, there was no sign of infection in the wound.

LESSONS

It is rare-reported that implanted bone displacement is caused by factors such as abscess formation. Treatment and understanding of implanted bone around the greater trochanter of the right femur is important. Early recognition and surgical removal of displaced implanted bone play a crucial role in infection control and disease prognosis.

Emerging Concepts for the Treatment of Biofilm-Associated Bone and Joint Infections with IV Fosfomycin: A Literature Review

Due to the involvement of biofilms in the pathogenesis of bone and joint infections (BJI), the treatment of these infections is often challenging, especially when multidrug- or extensively drug-resistant (MDR/XDR) pathogens are involved. Intravenous fosfomycin (FOS) is a phosphoenolpyruvate analogue with a unique mode of action and broad-spectrum activity against both Gram-positive (GP) and Gram-negative (GN) pathogens. It is used in various severe and deep-seated infections, including BJIs. This review article focuses on preclinical and clinical data surrounding the use of FOS for biofilm-related BJIs. Data from several in vitro and animal models of infection demonstrated that FOS, especially in combination with other antibiotics, is effective against biofilms of (methicillin-resistant) Staphylococcus spp., (vancomycin-resistant) Enterococcus spp., carbapenem-resistant and extended-spectrum beta-lactamase-producing Enterobacterales, and MDR Pseudomonas aeruginosa. Data from clinical studies, mostly retrospective observational studies and case reports/case series, revealed that FOS was typically used in combination with other antibiotics for the treatment of various BJI, including acute and chronic osteomyelitis, prosthetic joint infections, and fracture-related infections, in adult and pediatric patients. Success rates often exceeded 80%. FOS exhibits good and fast penetration into bone tissue and is generally well tolerated, with only a few adverse drug reactions, such as gastrointestinal disorders and electrolyte imbalances. Collectively, the data indicate that FOS is a valuable option as part of combination regimens for the treatment of BJIs caused by both GP and GN bacteria.

Animal Models of Orthopedic Implant-Associated Infections and Revisions

Orthopedic implant-associated infections such as prosthetic joint infections (PJIs) lead to devastating complications for patients and impose significant financial burdens on the healthcare systems. Although the primary orthopedic implant associated infection rate is relatively low (0.3-9%), the reinfection rate after implant revisions can be as high as 20% to 40%. To evaluate novel therapeutic strategies for preventing and treating infections associated with primary and revision implants, it is essential to develop appropriate animal models that closely emulate clinical realities. Here we discuss existing animal models developed for orthopedic implant revision surgeries including small animal models in rats and mice, and larger animal models in rabbits, sheep, and mini-pigs. While larger animal models offer the advantage of more closely mimicking human surgical procedures, implant dimensions, and infection treatment protocols, rodent models are more cost-effective and better suited for screening experimental prophylaxes and therapeutics. Existing animal revision models have focused on primary infections established by Staphylococcal aureus (S. aureus) and revisions involving both one-stage and two-stage procedures. Further development of smaller animal implant revision models that implement more clinically relevant surgical procedures and recapitulate polymicrobial infections could facilitate the discovery and more rigorous evaluation of novel implant coating prophylaxes and therapeutics for reducing reinfection rates following implant revisions.

Is there a cardiovascular risk associated with the use of fluoroquinolones for the treatment of osteoarticular infections? Analysis of a retrospective cohort of 817 patients from a surgical and infectious disease referral center (CRIOAC)

INTRODUCTION

Bone joint infection is a rare but serious complication, the treatment of which most often requires intervention combined with prolonged high-dose antibiotic therapy. Fluoroquinolones are among the standard antibiotics for the treatment of these infections, particularly in combination with rifampicin for staphylococcal infections and as monotherapy for Gram-negative bacilli infections. However, recent studies, confirmed by several meta-analyses, have highlighted an increased cardiovascular risk such as aortic aneurysm and mitro-aortic regurgitation occurring early following fluoroquinolone use, leading to recommendations for caution from health agencies. These meta-analyses are often based on limited series with numerous indication biases (variable treatment durations) and low doses. We therefore conducted a single-center, single-prescriber, real-life study of a continuous series of osteo-articular infections. The objectives were to determine the rate of cardiovascular events (aortic aneurysm, mitro-aortic regurgitation) at 60 days, the mortality rate at 60 days, and at the final follow-up.

HYPOTHESIS

Our hypothesis was that despite long-term, high-dose treatments, there was no increased cardiovascular risk in patients treated for osteo-articular infections with fluoroquinolones.

MATERIALS AND METHODS

Between 2017 and 2019, 817 patients were treated at the CRIOAC (Referral Center for Complex Osteo-Articular Infections) Lille-Tourcoing (332/817 patients received treatment with fluoroquinolones). This retrospective cohort study assessed the onset or worsening of cardiovascular events (such as aortic aneurysms and mitro-aortic regurgitation) and death at 2 months using a propensity score.

RESULTS

After propensity score weighting, there was no significant difference in the risk of aortic aneurysm and mitro-aortic regurgitation at 60 days (Odds ratio (OR) 0.921 [0.317; 2.673], p = 0.879) or in the risk of death at 60 days (OR 1.252 [0.502; 3.118]; p = 0.630). There was also no significant difference in the risk of death at last follow-up after propensity score weighting (OR 1.011 [0.646; 1.582], p = 0.962).

DISCUSSION

The results of this study suggest that the use of fluoroquinolones in patients treated for osteoarticular infections does not pose a significant increased risk of aortic aneurysm, mitro-aortic regurgitation, or death within two months. We believe it is reasonable to continue prescribing fluoroquinolones for osteoarticular infections while maintaining surveillance for these events.

LEVEL OF EVIDENCE

III; case-control study with propensity score.

Management strategies and outcomes for fracture-related infection of patellar fractures

INTRODUCTION

Fracture-related infection (FRI) poses a substantial challenge in orthopaedic trauma surgery, potentially leading to permanent functional impairment or necessitating amputation in patients who are expected to recover fully. Data on the incidence, pathogen detection rates, outcomes, and optimal management strategies for patellar FRI are limited. Therefore, this study aimed to identify the most common pathogens associated with patellar fixation-related infections, evaluate the functional outcome associated with FRI of the patella, and develop a management algorithm for addressing these severe complications.

METHODS

This retrospective review analyzed a prospectively maintained database to identify all patients with FRI of the patella treated at our institution between January 2015 and August 2023. Data on demographics, fracture characteristics, surgical details, and outcomes were collected. Descriptive statistical analyses were performed using SPSS software.

RESULTS

Over the 9-year period, 32 cases of patellar fractures complicated by infection following surgical treatment were identified, with complete follow-up data available (mean age, 56.5 ± 15.8 years). Infection occurred in 13 patients within 2 weeks of fixation and in 19 patients between 2 and 10 weeks postoperatively. Following debridement, nine patients retained their original fixation, eight underwent hardware removal, and 15 underwent hardware replacement. Seven patients developed septic arthritis and were managed with arthroscopic knee lavage. Metagenomic next-generation sequencing demonstrated a sensitivity of 93.8 % (30/32), which was significantly higher than that of traditional microbiological culture (53.1 %; P < 0.01). All surgical incisions achieved primary healing within 2 weeks post-closure with no recurrence of infection, skin necrosis, osteomyelitis, or nonunion. At the final follow-up, all fractures had united, with the Böstman patellar fracture functional scores ranging from 24 to 29, resulting in a 100 % excellent/good rate.

CONCLUSIONS

Comprehensive and multidisciplinary management approaches can achieve successful bone union and favourable long-term outcomes in patients with patellar FRI. However, further validation through large-scale studies is necessary to confirm these findings.

Fracture-Related Infections

Fracture-related infections are challenging complications in orthopedic care, marked by infection at fracture or surgical sites, often involving biofilm-associated pathogens. They result in significant morbidity, prolonged hospitalizations, and high health care costs. Diagnosis integrates clinical, laboratory, and imaging findings, while treatment combines surgical debridement, implant management, and targeted antimicrobial therapy. Common pathogens include Staphylococcus aureus and Staphylococcus epidermidis, with culture-negative cases requiring advanced diagnostics. A multidisciplinary approach is critical to optimizing outcomes, addressing complications, and reducing the socioeconomic impact of these infections. Advances in treatment strategies continue to improve survival and quality of life for affected patients.

Clinical application of combined CRP and PCT detection in diagnosing and prognosing fracture-related infections

Objective

To investigate the clinical significance of combined procalcitonin (PCT) and C-reactive protein (CRP) testing in the diagnosis of fracture-related infections (FRIs).

Methods

A retrospective analysis was performed on 252 patients with bone infections admitted between January 2018 and September 2024. CRP and PCT levels were measured in all patients both at diagnosis and postoperatively. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of combined CRP and PCT for diagnosing FRIs were calculated. Based on clinical follow-up data, patients were divided into low-level and high-level groups according to the changes in CRP and PCT levels, and clinical outcomes, including length of hospital stay and infection control, were analyzed.

Results

The postoperative levels of CRP and PCT in the infection group were significantly higher than in the control group (P < 0.05). The sensitivity, specificity, PPV, and NPV of combined CRP and PCT detection were 90.48%, 96.83%, 96.61%, and 91.04%, respectively. Patients in the high CRP and PCT group had a significantly longer hospital stay compared to the low-level group, and infection control rates were lower. Combined CRP and PCT detection was more effective in diagnosing and predicting clinical outcomes.

Conclusion

Combined detection of CRP and PCT has high clinical application value in the diagnosis and prognosis evaluation of fracture-related infections, providing more accurate guidance, particularly in predicting recovery and infection control.

Identification of clinical risk factors and optimal inflammatory marker cutoffs for the diagnosis of septic nonunion at time of presentation

PURPOSE

The diagnosis of septic nonunion is difficult due to the risk of occult presentation. The purpose of this study is to identify risk factors for infection prior to nonunion surgery.

METHODS

This retrospective cohort study was completed at a single tertiary referral level one trauma center. Patients were included if they had surgery to repair a nonunion of the femur, tibia, or humerus after operative initial management. Predictors for septic nonunion were determined based on clinical, laboratory, and radiographic findings.

RESULTS

122 Patients met inclusion criteria. 28 Patients (23.0%) were diagnosed with septic nonunion. Clinical risk factors for septic nonunion diagnosis on multivariate regression included nonunion surgery performed at an outside hospital prior to referral (p = 0.003) and early infection requiring debridement within 60 days of initial injury (p = 0.01). Ideal inflammatory marker cutoffs based on ROC curves included WBC > 8.1 × 109/L (p = 0.001) and CRP > 14.1 mg/L (p = 0.001).

CONCLUSION

This study demonstrates additional clinical risk factors and re-defines cutoff values for laboratory biomarkers as predictors for diagnosis of septic nonunion. These data may help providers better identify cases of septic nonunion prior to nonunion surgery.

Microbiota shifts in fracture-related infections and pathogenic transitions identified by 16S rDNA sequencing

Fracture-related infection (FRI) is a major challenge in orthopaedic trauma. Understanding of the microbial shift with respect to the initial contamination to infection phase is crucial. This study was to examine the wound microbiota associated with FRI in a prospective cohort study of 155 patients with Gustilo-Anderson Type II, IIIA or IIIB open fractures. Tissue samples were systematically collected from all patients during initial surgical debridement. Out of these, patients who developed infection (FRI group, n = 28) had a second tissue sampling during re-debridement. Conversely, patients who achieved normal healing and subsequently received definitive open reduction and internal fixation served as control (NH group, n = 24). Marked differences between all groups were revealed in the 16S rDNA analysis of microbial communities. The species richness was higher in the Pre-FRI group, but bacterial diversity declined significantly in the FRI group after infection onset. In the Pre-FRI and Pre-NH groups, Firmicutes were the dominating phylum, while in the FRI and NH groups, Proteobacteria and Actinobacteria appeared more prevalent, respectively. In Pre-FRI notably abundant Bacillus and Staphylococcus and in FRI, the most pathogens were Enterobacter and Pseudomonas. The NH group maintained balanced microbial diversity. These findings suggest that declining microbiota diversity and shifts towards dominant pathogens in open fracture patients may serve as early indicators of infection risk, with Bacillus potentially emerging as a predictive biomarker for FRI susceptibility.

Fracture-Related Infections in the Foot and Ankle

Fracture-related infection (FRI) poses significant challenges in the management of foot and ankle fractures, potentially leading to functional impairment and heightened health care expenses. This review addresses the diagnosis, risk factors, and management strategies for FRI. Surgical management involves multidisciplinary collaboration, emphasizing debridement, antimicrobial therapy, and implant removal when indicated. Specific considerations for limited soft tissue coverage, tenuous blood supply, and fracture type in the foot and the ankle underscore the importance of tailored approaches to optimize outcomes and reduce complications in FRI management.

Combining antibacterial and wound healing features: Xanthan gum/guar gum 3D-printed scaffold tuned with hydroxypropyl-β-cyclodextrin/thymol and Zn2

Biofilm formation on biological and material surfaces represents a heavy health and economic burden for both patient and society. To contrast this phenomenon, medical devices combining antibacterial and pro-wound healing abilities are a promising strategy. In the present work, Xanthan gum/Guar gum (XG/GG)-based scaffolds were tuned with thymol and Zn2+ to obtain wound dressings that combine antibacterial and antibiofilm properties and favour the healing process. The tuning process preserved the 3D extrusion-based printability of the XG/GG ink. Scaffolds swelling profile was assessed in PBS pH 7.4, and the resistance to compressive forces was studied using a texturometer. The scaffolds microarchitectures were analyzed by SEM, while ATR-FTIR spotlighted the chemical modifications of the customized materials. Thymol and Zn2+ release was analyzed in biologically relevant media, showing a burst release in the first hours. The antibacterial properties were confirmed against S. aureus, P. aeruginosa, and S. epidermidis by isothermal microcalorimetry and biofilm viable cell counting. Incorporation of hydroxypropyl-β-cyclodextrin (HPβCD) improved thymol loading (7- and 14-times higher thymol content) and enhanced the antimicrobial and antioxidant performances of the dressing, while the presence of Zn2+ strongly potentiated the antimicrobial activity, showing a potent antibiofilm response in both Gram-positive and Gram-negative strains of clinical concern. The thymol and Zn2+ combination led to a reduction of 99.95 %, 99.99 %, and 98.26 %, of biofilm formation against S. aureus, P. aeruginosa, and S. epidermidis, respectively. Furthermore, the scaffolds demonstrated good hemocompatibility, cytocompatibility, tissue integration and pro-angiogenic features in an in ovo CAM model.

Timing in orthopaedic surgery - Rethinking traditional myths with a critical perspective

PURPOSE

Standard operating procedures aim to achieve a standardized and assumedly high-quality therapy. However, in orthopaedic surgery, the aspect of temporal urgency is often based on surgical tradition and experience. At a time of evidence-based medicine, it is necessary to question these temporal guidelines. The following review will therefore address the most important temporal guidelines in orthopaedic surgery and discuss their practical relevance and potential need for optimization.

METHODS

The systematic review features a literature review by database search in "PubMed" (https://pubmed.ncbi.nlm.nih.gov) for time to surgery in terms of (1) "proximal femoral fractures", (2) "femoral neck fractures", (3) "proximal humeral fractures", (4) "ligament and tendon injuries", (5) "spinal cord injuries", (6) "open fractures" and (7) "fracture-related infections". For every diagnosis, hypotheses on timing were set up and checked for evidence.

RESULTS

There is solid clinical evidence supporting the initiation of treatment within 24 h for specific conditions like the surgical treatment of proximal femur fractures and prompt decompression of spinal cord injuries. However, for other scenarios such as the 6-hour rule for open fractures, joint-preserving femoral neck fractures, timing of ligament injuries, humeral head fractures and fracture-related infections there is currently no reliable evidence to guide prompt surgical treatment.

CONCLUSION

Based on the current data, resource-adapted surgical planning seems reasonable. Further research in these areas is necessary to determine the best timing of treatment and address existing doubts.

Irrigation of the intramedullary channel improves outcome of DAIR in a sheep model

The management of fracture-related infection (FRI) with Debridement, Antibiotics, Irrigation, and Implant Retention (DAIR) is an appealing option, but its suitability is restricted to a relatively narrow proportion of patients. This study aimed to create a large animal model of DAIR after FRI and to evaluate outcomes after early (2 weeks) and delayed (5 weeks) DAIR. Additionally, intramedullary lavage (IML) of the intramedullary canal (IMC) is introduced as a novel technique to remove infected tissue. Our findings showed that DAIR failed to resolve infections in both early and delayed groups, whilst IML significantly reduced bacterial counts, leading to culture-negative results in the soft tissue and bone marrow. IML did not compromise long-term bone healing as revealed by an implant load sensor on the plate. In conclusion, DAIR was successfully achieved in a new large animal model with minimal losses. The IML method improves treatment efficacy, potentially broadening the range of patients suitable for DAIR.

Fracture-related infections of the lower extremity - Analysis of costs and their drivers

OBJECTIVES

Fracture-related infection (FRI) is a feared complication in orthopaedic trauma surgery. They are associated with multiple surgical interventions and prolonged antibiotic treatment duration, and hence, increased costs. The objective of this study was to assess the costs of FRI treatment in a Tertiary Swiss Trauma Center and to identify the variables associated with increased costs.

PATIENTS AND METHODS

In this retrospective cohort study, 116 patients with an FRI treated in a Swiss tertiary center between 01/2012 and 12/2019 were included. Clinical data and the costs of each hospital stay were evaluated. Predefined variables were categorized as modifiable and non-modifiable factors and examined for their influence on costs and hospital length of stay (LOS) in univariable and multivariable analyses.

RESULTS

The median cost per patient was 39,219 [interquartile range (IQR) 22,657 to 68,588] CHF. The median LOS was 21 [IQR 14 to 36] days. Most patients were male (67%) with a median age of 58 years [40-70]. The median duration of IV antibiotic use was 16 [9-27] days. Costs related to hospitalization (nursing and physiotherapy) accounted for the highest expenses with a relative share of 49%, whereas surgical procedures had a minor impact on the total cost with a relative share of 19%. In the univariable analysis, significant drivers of both costs and LOS were the number of FRI surgeries, the use of negative pressure wound therapy, duration of IV antibiotic treatment, and cases with a change of surgical strategy. After adjustment for patient and treatment factors, duration of IV antibiotics and change of surgical strategy were associated with higher costs.

CONCLUSIONS

This study illustrates the financial burden of FRI in a DRG system and identifies potential drivers for these costs. Since repeated surgeries or unplanned surgical revisions are drivers of costs, optimal pre-operative planning and coordination between the involved disciplines is key to minimize costs. Management in multidisciplinary teams that are specialized in the treatment of these complex and cost-intensive patients may therefore reduce the financial burden.

Marginal bone resection and immediate internal fixation in multidrug resistant chronic septic nonunions of lower limb long bones: a case series

PURPOSE

This study aimed to evaluate the efficacy of a combined treatment approach integrating extensive debridement, immediate internal fixation, and the Masquelet technique for the management of infected nonunion of long bones in the lower limbs caused by multidrug-resistant (MDR) and extensively drug-resistant (XDR) bacteria.

METHODS

This retrospective case series was conducted at the Imam Khomeini Hospital Complex, Tehran, Iran, a tertiary-level academic referral centre. The study documented consecutive cases of patients presenting with infected nonunion of the tibia or femur, with a positive culture for MDR or XDR bacteria, treated between January 2019 and December 2022. Inclusion criteria were adults with a confirmed diagnosis of infected nonunion due to MDR or XDR bacteria, with exclusion criteria including patients with unrelated infections or allergies to the components of the treatment regimen. The primary outcomes measured were infection resolution and bone healing.

RESULTS

The study cohort comprised 16 patients, predominantly male (87.5%) with an average age of 38.5 years. Methicillin-resistant Staphylococcus aureus (MRSA) was identified as the causative agent in 31.25% of the infections. Patients were followed for a period ranging from 12 to 26 months. The treatment protocol was uniformly applied across all cases. Successful bone union was observed in the majority of patients within 140 to 240 days following grafting. However, there were two instances where amputation was necessitated due to the failure to eradicate the infection. Complications arose in three cases during the follow-up period: two required re-debridement due to a recurrence of the infection, and one was subjected to bone transport owing to persistent nonunion. Notably, all cases that either failed or encountered complications were smokers.

CONCLUSIONS

In this integrated approach, high rates of infection resolution and bone healing were achieved, suggesting this method as a viable option for these complex cases.

Epidemiology and Outcomes of Infected Non-Unions: An Observational Study at an Infectious Disease Referral Centre

Objectives: The main aim of this study was to describe the epidemiology of infected non-unions (INUs) managed at an Infectious Disease (ID) referral centre and to investigate the factors associated with treatment failure. Methods: This was an observational retrospective study on adult patients with INUs managed between 2012 and 2018 at the ID Unit of the IRCCS Azienda Ospedaliero-Universitaria di Bologna, an Italian ID referral centre for bone and joint infections. Patients were observed for at least 24 months. Those who achieved clinical success were compared with those who experienced clinical failure; to identify factors associated with treatment failure, we performed a univariate and multivariate logistic regression analysis. Results: Overall, 78 patients were included. A total of 57/78 (73%) were males; their median age was 43 (IQR 34-56) years; their median Charlson index was 0 (IQR 0-2); 32/78 (41%) reported a history of an open fracture; the non-union most frequently involved the leg. Polymicrobial infection was found in 23/78 cases (29%); the most common microorganisms were coagulase-negative staphylococci (n = 47) and Staphylococcus aureus (n = 35). At 24-month follow-up from index surgery, 16/78 patients had experienced clinical failure: 13 (16.6%) presented with persistence of local signs of infection and 3 (3.8%) had undergone amputation. Logistic regression analysis of risk factors for clinical failure identified body mass index (BMI) (aOR 1.15; 95% CI 1.03-1.28, p = 0.01) and MRSA infection (aOR 5.35; 95% CI 1.06-26.92, p = 0.04) as factors associated with clinical failure. Conclusions: Given that a standardized management of antibiotic therapy is initiated by an expert ID consultant team, BMI and MRSA infection are associated with worse outcomes among patients with INUs.

Fracture-Related Infection Diagnostic Tools in the Upper Extremity: A Scoping Review

Fracture-related infection (FRI) is a serious orthopaedic complication and its diagnosis, particularly in the upper extremity, is difficult and poorly defined in current literature. An international consensus definition of FRI was published in 2018, and our scoping review aims to investigate FRI diagnostic tools reported in the primary literature and their biostatistical utility. A review of articles generated from the PubMed/NCBI search term "fracture-related infection" was undertaken using PRISMA methodology. The included studies were published from January 2018 to June 2022 and referred to FRI diagnosis in the upper extremity. Of 224 returned studies, 32 articles were selected for further review after fellowship-trained senior author assessment. Of these, 16 had quantitative and reportable data regarding the diagnosis of upper extremity FRI. The most common diagnostic methods reported were CRP (8 studies), WBC (7), and ESR (5), consistent with 1 of the six suggestive criteria from the consensus definition. Meta-analysis was performed. Primary literature regarding the diagnosis of upper extremity fracture-related infections is sparse and variable despite FRI's diagnostic and therapeutic complexity. Recent literature does not reflect the proposed criteria of the 2018 consensus definition; further primary research is needed to validate these criteria and their accuracy and utility Level of Evidence: 3b.

Development and validation of a preclinical canine model for early onset fracture-related infections

Fracture-related infections (FRIs) are a challenging complication in orthopaedics. Standard of care management for FRIs typically involves prolonged antibiotic therapies, irrigation and debridement (I&D) of the fracture site, and retention of fracture-fixation implants with or without exchange. Unfortunately, this treatment regimen is associated with treatment failure rates of up to 38 %, such that improved preventive and therapeutic interventions are needed. To test and develop these interventions, clinically relevant preclinical animal models are required. The purpose of this study was to develop and validate a canine model for early onset (<2 weeks) FRI that replicates its clinical, radiographic, bacteriologic, and histologic features. In this model, bilateral proximal fibular 1-cm ostectomies were created to mimic an open fracture, which was then stabilized using a plate and screws pre-incubated in methicillin-resistant Staphylococcus aureus (MRSA). After 7 days, I&D was performed and twice-daily systemic antibiotics were administered until the 17-day endpoint. This model consistently resulted in clinical signs of local infection, compromised wound healing, radiographic evidence for delayed bone healing and implant loosening, and implant-associated biofilm formation. Importantly, MRSA was isolated from deep tissue cultures in all dogs, and histological assessments detected bacteria and bacterial biofilms associated with all fracture-fixation implants at the study endpoint. These clinical, radiographic, bacteriologic, and histologic outcomes in conjunction with the capabilities for standard of care interventions, such as antibiotic treatment and I&D, verify that this preclinical canine model for early onset FRI effectively replicated the pathology associated with this commonly encountered complication of orthopaedic trauma.

The DAIR-procedure in fracture-related infection-When and how

This narrative review discusses treatment strategies and key considerations guiding decisions in the surgical management of fracture-related infections (FRI). Treatment options primarily revolve around two approaches: debridement antibiotics and implant retention (DAIR), or implant exchange, either in a one or multiple-stage strategy. Several considerations, including time since infection onset, implant type, stability, causative pathogens, host physiology, and soft tissue conditions, inform the choice of surgical intervention for FRI. Current literature supports the preference for a DAIR approach in cases with a short duration of ongoing symptoms, a stable implant with satisfactory fracture reduction, and a viable soft tissue envelope. Conversely, one- or multiple-stage implant exchange is deemed beneficial in instances of compromised local and systemic host physiology, mature biofilm, difficult-to-treat pathogens, intramedullary implants, and cases involving reinfections or failed DAIR procedures. Notably, these recommendations draw parallels from periprosthetic joint infection treatment strategies, constrained by the limited availability of randomized controlled trials comparing these options specifically in acute FRI. In conclusion, future perspectives call for extensive investigations into biofilm maturation and the impact of time on treatment outcomes. Additionally, there is a need for a standardized classification system for FRI to enhance the comparability of treatment outcomes in FRI management.

Phage therapy: A primer for orthopaedic trauma surgeons

Phage therapy (PT) continues to attract interest in the fight against fracture-related infection (FRI), particularly for recurring infections that have not been resolved using conventional therapeutic approaches. The journey PT has taken from early clinical application in the pre-antibiotic era to its recent reintroduction to western clinical practice has been accelerated by the increased prevalence of multi-drug resistant (MDR) pathogens in the clinic. This review will present PT's potential as a precise, adaptable, and effective treatment modality, with a focus on patient and phage selection, as well as the various administration protocols currently applied to patients. The challenges for PT, for example the most optimal application technique and dosing, are also discussed and underscore the importance of personalized approaches and the urgent need for more robust clinical evidence. Future perspectives, including phage engineering and innovative delivery systems will be discussed, as they may broaden the applicability of PT to a point where it may become a standard rather than an option of last resort for orthopedic infection management.

Effect of mechanical stability of osteosynthesis on infection rates: Timing of temporary and definitive fixation

Fracture related infection (FRI) remains one of the most challenging complications of orthopaedic trauma surgery. Several factors contribute to FRI development but, among those, particularly interesting from the orthopaedic surgeon's perspective is the contribution of mechanical stability and timing of fracture fixation. These are indeed crucial factors both in prevention and treatment of FRI and are directly influenced by the surgeon's work. While the role of stability has been studied and discussed, the pathophysiological process regulating such role and how this influences surgeon's treatment decision making is still debated. The same applies to the ideal timing of temporary or definitive fixation which varies according to the clinical scenario considered. In the present narrative review, we described the influence of mechanical stability on both FRI pathophysiology and on the decision making of FRI treatment. In addition, we analysed the impact of the timing of fracture fixation on the risk of FRI development particularly in those clinical scenarios where it has been shown to be specifically relevant, such as fractures affecting segments with poor soft tissue envelope, open fractures, damage control orthopaedics, and the need for soft tissue coverage.

Locally Delivered Antibiotics in Fracture-Related Infection

The prevention and treatment of fracture-related infections (FRIs) pose significant challenges in orthopaedic trauma care, with current practices predominantly relying on systemic antibiotic administration. However, locally delivered antibiotics achieve substantially higher tissue concentrations and minimise systemic side effects. Whilst extensively researched in periprosthetic joint infections (PJIs), the use of local delivery methods is increasingly prevalent in FRI prevention and treatment. Various local delivery methods such as powders, aqueous injections and carriers such as cement, bone graft, bioceramics, polymers and hydrogels have been explored. Biodegradable antibiotic carriers offer a promising alternative to non-absorbable carriers (i.e., cement), which necessitate surgical removal. There is good evidence for the use of local antibiotics in preventing and treating FRI, particularly in high-risk fractures or in treating more severe, resistant infections. Despite theoretical concerns, reports of adverse events in human studies are rare. To enhance our understanding of the safety and efficacy of these methods across various fracture patterns, further prospective randomised controlled trials are warranted. This article describes the current strategies and methodologies for FRI prevention and treatment and reviews the existing evidence base.

Nanoarchitecture-Integrated Hydrogel Boosts Angiogenesis-Osteogenesis-Neurogenesis Tripling for Infected Bone Fracture Healing

Infected fracture healing is a complicated process that includes intricate interactions at the cellular and molecular levels. In addition to angiogenesis and osteogenesis, the significance of neurogenesis in fracture healing has also been recognized in recent years. Here, a nanocomposite hydrogel containing pH-responsive zinc-gallium-humic acids (HAs) nanoparticles is developed. Through the timed release of Zn2+, Ga3+, and HAs, the hydrogel exhibits potent antibacterial effects and promotes angiogenesis, osteogenesis, and neurogenesis. The enhanced neurogenesis further promotes angiogenesis and osteogenesis, forming a mutually supportive angiogenesis-osteogenesis-neurogenesis cycle at the fracture site. The hydrogel achieves rapid infected fracture healing and improves tissue regeneration in mice. This study proposes a comprehensive treatment approach that combines antibacterial effects with the regulation of tissue regeneration to improve infected fracture healing.

Management of Fracture-Related Infection in Conflict Zones: Lessons Learned from Medical Missions to Gaza

Background/Objectives: Fracture-related infections (FRIs) are a significant complication in conflict zones, where limited resources and damaged infrastructure complicate orthopedic care. Methods: This study retrospectively reviews the management of FRIs during medical missions to Gaza from April to July 2024. Results: Among 135 patients treated for war-related fractures, 30% were identified with suspected FRIs, which were primarily following explosive injuries. Contributing factors to the high incidence of infection included malnutrition, poor sanitation, and the scarcity of sterile surgical supplies. The absence of standard infection control measures further complicated treatment. Conclusions: These findings highlight the critical need for a comprehensive approach that incorporates infection prevention, sustainable healthcare planning, and quality assurance tailored to the realities of conflict zones. The study underscores the importance of international support to ensure the availability of essential medical supplies and to develop effective, context-specific strategies for infection management. By applying these insights, healthcare providers can improve patient outcomes and reduce the burden of FRIs in resource-limited settings affected by conflict.

An Andrias davidianus derived composite hydrogel with enhanced antibacterial and bone repair properties for osteomyelitis treatment

Effective antibacterial therapy while accelerating the repair of bone defects is crucial for the treatment of osteomyelitis. Inspired by the protective mechanism of Andrias davidianus, we constructed an antibacterial hydrogel scaffold with excellent rigidity and long-term slow-release activity. While retaining the toughness of the skin secretion of Andrias davidianus (SSAD), the rigidity of the hydrogel material is increased by incorporating hydroxyapatite to meet the demands of bone-defect-filling materials. It also exerted antibacterial effects via the slow-release of vancomycin from local osteomyelitis lesions. Notably, the hydrogel can also carry a high stable recombinant miR-214-3p inhibitor (MSA-anti214). By the delivery of nano vector polyvinylamine, the long-term slow-release of MSA-anti214 is achieved to promote bone repair, making this composite hydrogel a potential SSAD-based osteomyelitis alleviator (SOA). In vitro and vivo results verified that the SOA effectively eliminated Staphylococcus aureus and repaired bone defects, ultimately mitigating the progression of osteomyelitis. This composite hydrogel extends the economic application prospects of A. davidianus and has provided new insights for the treatment of osteomyelitis. The study also explored new insights for the bone filling materials of bone defection and other skeletal system diseases.

Orthopedic revolution: The emerging role of nanotechnology

This review summarizes the latest progress in orthopedic nanotechnology, explores innovative applications of nanofibers in tendon repair, and evaluates the potential of selenium and cerium oxide nanoparticles in osteoarthritis and osteoblast differentiation. This review also describes the emerging applications of injectable hydrogels in cartilage engineering, emphasizing the critical role of interdisciplinary research and highlighting the challenges and future prospects of integrating nanotechnology into orthopedic clinical practice. This comprehensive approach provides a holistic perspective on the transformative impact of nanotechnology in orthopedics, offering valuable insights for future research and clinical applications.

LL-37 and bisphosphonate co-delivery 3D-scaffold with antimicrobial and antiresorptive activities for bone regeneration

This study introduces a novel 3D scaffold for bone regeneration, composed of silk fibroin, chitosan, nano-hydroxyapatite, LL-37 antimicrobial peptide, and pamidronate. The scaffold addresses a critical need in bone tissue engineering by simultaneously combating bone infections and promoting bone growth. LL-37 was incorporated for its broad-spectrum antimicrobial properties, while pamidronate was included to inhibit bone resorption. The scaffold's porous structure, essential for cell infiltration and nutrient diffusion, was achieved through a freeze-drying process. In vitro assessments using SEM and FTIR confirmed the scaffold's morphology and chemical integrity. Antimicrobial efficacy was tested against pathogens of Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa). In vivo studies in a murine model of infectious bone defect revealed the scaffold's effectiveness in reducing inflammation and bacterial load, and promoting bone regeneration. RNA sequencing of treated specimens provided insights into the molecular mechanisms underlying these observations, revealing significant gene expression changes related to bone healing and immune response modulation. The results indicate that the scaffold effectively inhibits bacterial growth and supports bone cell functions, making it a promising candidate for treating infectious bone defects. Future studies should focus on optimizing the release of therapeutic agents and evaluating the scaffold's clinical potential.

Targeting Bacteria-Induced Ferroptosis of Bone Marrow Mesenchymal Stem Cells to Promote the Repair of Infected Bone Defects

The specific mechanisms underlying bacteria-triggered cell death and osteogenic dysfunction in host bone marrow mesenchymal stem cells (BMSCs) remain unclear, posing a significant challenge to the repair of infected bone defects. This study identifies ferroptosis as the predominant cause of BMSCs death in the infected bone microenvironment. Mechanistically, the bacteria-induced activation of the innate immune response in BMSCs leads to upregulation and phosphorylation of interferon regulatory factor 7 (IRF7), thus facilitating IRF7-dependent ferroptosis of BMSCs through the transcriptional upregulation of acyl-coenzyme A synthetase long-chain family member 4 (ACSL4). Moreover, it is found that intervening in ferroptosis can partially rescue cell injuries and osteogenic dysfunction. Based on these findings, a hydrogel composite 3D-printed scaffold is designed with reactive oxygen species (ROS)-responsive release of antibacterial quaternized chitosan and sustained delivery of the ferroptosis inhibitor Ferrostatin-1 (Fer-1), capable of eradicating pathogens and promoting bone regeneration in a rat model of infected bone defects. Together, this study suggests that ferroptosis of BMSCs is a promising therapeutic target for infected bone defect repair.

Biofilm Formation, Antibiotic Resistance, and Infection (BARI): The Triangle of Death

Fracture-related infection (FRI) is a devastating event, directly affecting fracture healing, impairing patient function, prolonging treatment, and increasing healthcare costs. Time plays a decisive role in prognosis, as biofilm maturation leads to the development of antibiotic resistance, potentially contributing to infection chronicity and increasing morbidity and mortality. Research exploring the association between biofilm maturation and antibiotic resistance in orthopaedics primarily addresses aspects related to quality of life and physical function; however, little exists on life-threatening conditions and mortality. Understanding the intrinsic relationship between biofilm maturation, bacterial resistance, and mortality is critical in all fields of medicine. In the herein narrative review, we summarize recent evidence regarding biofilm formation, antibiotic resistance, and infection chronicity (BARI), the three basic components of the "triangle of death" of FRI, and its implications. Preoperative, perioperative, and postoperative prevention strategies to avoid the "triangle of death" of FRI are presented and discussed. Additionally, the importance of the orthopaedic trauma surgeon in understanding new tools to combat infections related to orthopaedic devices is highlighted.

Fracture-related infections after osteosynthesis for hip fracture are associated with higher mortality: A retrospective single-center cohort study

BACKGROUND AND PURPOSE

 Fracture-related infections (FRIs) after osteosynthesis for hip fractures have not been thoroughly investigated. Our primary aim was to assess the association between FRIs and mortality after osteosynthesis for hip fracture. Secondary aims were to investigate the incidence, microbiology, and general epidemiological aspects of these FRIs.

METHODS

 This retrospective single-center study included 1,455 patients > 18 years old with non-pathological hip fractures treated with osteosynthesis between 2015 and 2019. Medical records were reviewed and FRIs were diagnosed based on current consensus criteria. The follow-up period was 2 years. Mortality was estimated using Kaplan-Meier survival analysis. Cox regression analyses were performed to investigate the potential association between FRIs, as a time-dependent variable, and increased mortality.

RESULTS

The median age for the entire cohort was 83 (interquartile range 75-89) years and 69% were females. At the 2-year follow-up mark, the crude mortality rate was 33% in the non-FRI group and 69% (11 of 16 patients) in the FRI group. Cox regression analysis assessing mortality risk revealed a hazard ratio of 3.5 (95% confidence interval [CI] 1.9-6.4) when adjusted for confounders. The incidence of FRI was 1.1% (16 of 1,455 patients). Staphylococcus aureus was the most common pathogen. Most FRI patients (94%) required at least 1 revision and 56% underwent ≥ 2 revision.

CONCLUSION

 We found an association between FRIs after hip fracture osteosynthesis and increased mortality, underscoring the critical need for FRI prevention measures in this frail patient group. The incidence and microbiological findings were consistent with previous studies.

Does Local Aqueous Tobramycin Injection Reduce Open Fracture-Related Infection Rates?

OBJECTIVES

To examine the effect of local aqueous tobramycin injection adjunct to perioperative intravenous (IV) antibiotic prophylaxis in reducing fracture-related infections (FRIs) following reduction and internal fixation of open fractures.

METHODS

DESIGN

Retrospective cohort study.

SETTING

Single academic Level I trauma center.

PATIENTS SELECTION CRITERIA

Patients with open extremity fractures treated with reduction and internal fixation with (intervention group) or without (control group) 80 mg of local aqueous (2 mg/mL) tobramycin injected during closure at the time of definitive fixation were identified from December 2018 to August 2021 based on population-matched demographic and injury characteristics.

OUTCOME MEASURES AND COMPARISONS

The primary outcome was FRI within 6 months of definitive fixation. Secondary outcomes consisted of fracture nonunion and bacterial speciation. Differences in outcomes between the 2 groups were assessed and logistic regression models were created to assess the difference in infection rates between groups, with and without controlling for potential confounding variables, such as sex, fracture location, and Gustilo-Anderson classification.

RESULTS

An analysis of 157 patients was performed with 78 patients in the intervention group and 79 patients in the control group. In the intervention group, 30 (38.5%) patients were women with a mean age of 47.1 years. In the control group, 42 (53.2%) patients were women with a mean age of 46.4 years. The FRI rate was 11.5% in the intervention group compared with 25.3% in the control group ( P = 0.026). After controlling for sex, Gustilo-Anderson classification, and fracture location, the difference in FRI rates between groups remained significantly different ( P = 0.014).

CONCLUSIONS

Local aqueous tobramycin injection at the time of definitive internal fixation of open extremity fractures was associated with a significant reduction in FRI rates when administered as an adjunct to intravenous antibiotics, even after controlling for potential confounding variables.

LEVEL OF EVIDENCE

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

Future directions for early detection of fracture related infections

Introduction

Fracture related infection (FRI) refers to pathogens infecting a fracture site and hence impeding fracture healing. It is a significant complication that carries substantial disease burden and socio-economic costs, but has had limited scientific development. Hence, this paper will review the existing strategies for early detection of FRI, in the form of serum markers, molecular diagnostics and imaging modalities, and further discuss potential future directions for improved detection of FRI.

Existing Strategies for Diagnosis of FRI

The Anti-infection Global Expert Committee (AIGEC) developed a consensus definition for FRI in 2017, which includes confirmatory and suggestive criteria for diagnosis of FRI. Existing strategies for diagnosis include clinical, laboratory, histopathological, microbiological and radiological investigations.

Future Directions for Early Detection of FRI

With increasing recognition of FRI, early detection is crucial for early treatment to be enforced. We have identified potential areas for future development in diagnostics for early detection of FRI, which are discussed in this manuscript. They include inflammatory cytokines, serum calcium levels, platelet count, improved management of histopathological and microbiological specimens, metagenomics, wound biomarkers, gut microbiota analysis, and novel imaging technologies.

Lower Extremity Amputation in Fracture-Related Infection

OBJECTIVES

To analyze demographics, comorbidities, fracture characteristics, presenting characteristics, microbiology, and treatment course of patients with fracture-related infections (FRIs) to determine risk factors leading to amputation.

METHODS

DESIGN

Retrospective cohort.

SETTING

Single Level I Trauma Center (2013-2020).

PATIENT SELECTION CRITERIA

Adults with lower extremity (femur and tibia) FRIs were identified through a review of an institutional database. Inclusion criteria were operatively managed fracture of the femur or tibia with an FRI and adequate documentation present in the electronic medical record. This included patients whose primary injury was managed at this institution and who were referred to this institution after the onset of FRI as long as all characteristics and risk factors assessed in the analysis were documented. Exclusion criteria were infected chronic osteomyelitis from a non-fracture-related pathology and a follow-up of less than 6 months.

OUTCOME MEASURES AND COMPARISONS

Risk factors (demographics, comorbidities, and surgical, injury, and perioperative characteristics) leading to amputation in patients with FRIs were evaluated.

RESULTS

A total of 196 patients were included in this study. The average age of the study group was 44±16 years. Most patients were men (63%) and White (71%). The overall amputation rate was 9.2%. There were significantly higher rates of chronic kidney disease (CKD; P = 0.039), open fractures (P = 0.034), transfusion required during open reduction internal fixation (P = 0.033), Gram-negative infections (P = 0.048), and FRI-related operations (P = 0.001) in the amputation cohort. On multivariate, patients with CKD were 28.8 times more likely to undergo amputation (aOR = 28.8 [2.27 to 366, P = 0.010). A subanalysis of 79 patients with either a methicillin-sensitive Staphylococcus aureus or methicillin-resistant S. aureus (MRSA) infection showed that patients with MRSA were significantly more likely to undergo amputation compared with patients with methicillin-sensitive Staphylococcus aureus (P = 0.031). MRSA was present in all cases of amputation in the Staphylococcal subanalysis.

CONCLUSIONS

Findings from this study highlight CKD as a risk factor of amputation in the tibia and femur with fracture-related infection. In addition, MRSA was present in all cases of Staphylococcal amputation. Identifying patients and infection patterns that carry a higher risk of amputation can assist surgeons in minimizing the burden on these individuals.

LEVEL OF EVIDENCE

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

Biodegradable implant of magnesium/polylactic acid composite with enhanced antibacterial and anti-inflammatory properties

Addressing fracture-related infections (FRI) and impaired bone healing remains a significant challenge in orthopedics and stomatology. Researchers aim to address this issue by utilizing biodegradable biomaterials, such as magnesium/poly lactic acid (Mg/PLA) composites, to offer antibacterial properties during the degradation of biodegradable implants. Existing Mg/PLA composites often lack sufficient Mg content, hindering their ability to achieve the desired antibacterial effect. Additionally, research on the anti-inflammatory effects of these composites during late-stage degradation is limited. To strengthen mechanical properties, bolster antibacterial efficacy, and enhance anti-inflammatory capabilities during degradation, we incorporated elevated Mg content into PLA to yield Mg/PLA composites. These composites underwent in vitro degradation studies, cellular assays, bacterial tests, and simulation of the PLA degradation microenvironment. 20 wt% and 40 wt% Mg/PLA composites displayed significant antibacterial properties, with three composites exhibiting notable anti-inflammatory effects. In contrast, elevated Mg content detrimentally impacted mechanical properties. The findings suggest that Mg/PLA composites hold promise in augmenting antibacterial and anti-inflammatory attributes within polymers, potentially serving as temporary regenerative materials for treating bone tissue defects complicated by infections.

Mechanisms and Intervention of Prebiotic Foods in Musculoskeletal Health

The review focuses primarily on collating and analyzing the mechanistic research data that discusses the function of prebiotics to halt the frailty of musculoskeletal system. Musculoskeletal diseases (MSDs) are frequently reported to co-occur within their own categories of conditions, such as osteoarthritis, rheumatoid arthritis, gouty arthritis, and psoriatic arthritis owing to their overlapping pathogenesis. Consequently, the same drugs are often used to manage the complications of most types. A few recent studies have addressed the therapeutic functions of gut microbes toward those commonly shared MSD pathway targets. Improving microbial diversity and enriching their population in the gut would promote the regeneration and recovery of the musculoskeletal system. Prebiotics are usually nondigestible substrates that are selectively used or digested by the gut microbes conferring health promotion. The microbial fermentation of prebiotics generates numerous host-beneficial therapeutic molecules. This study inspects the presumptive functions of plant-derived prebiotics for the growth and restoration of intestinal microbiota and the consequent improvement of skeletal health. The review also highlights the discrete functions of prebiotics against inflammation, autoimmunity, infection, physiologic overloading mechanism, and aging-associated loss of metabolism in MSD.

Managing more than bones: the psychological impact of a recurrent fracture-related infection

Aims

Fracture-related infections (FRIs) are a devastating complication of fracture management. However, the impact of FRIs on mental health remains understudied. The aim of this study was a longitudinal evaluation of patients' psychological state, and expectations for recovery comparing patients with recurrent FRI to those with primary FRI.

Methods

A prospective longitudinal study was conducted at a level 1 trauma centre from January 2020 to December 2022. In total, 56 patients treated for FRI were enrolled. The ICD-10 symptom rating (ISR) and an expectation questionnaire were assessed at five timepoints: preoperatively, one month postoperatively, and at three, six, and 12 months.

Results

Recurrent FRI cases consistently exceeded the symptom burden threshold (0.60) in ISR scores at all assessment points. The difference between preoperative-assessed total ISR scores and the 12-month follow-up was not significant in either group, with 0.04 for primary FRI (p = 0.807) and 0.01 for recurrent FRI (p = 0.768). While primary FRI patients showed decreased depression scores post surgery, recurrent FRI cases experienced an increase, reaching a peak at 12 months (1.92 vs 0.94; p < 0.001). Anxiety scores rose for both groups after surgery, notably higher in recurrent FRI cases (1.39 vs 1.02; p < 0.001). Moreover, patients with primary FRI reported lower expectations of returning to normal health at three (1.99 vs 1.11; p < 0.001) and 12 months (2.01 vs 1.33; p = 0.006).

Conclusion

The findings demonstrate the significant psychological burden experienced by individuals undergoing treatment for FRI, which is more severe in recurrent FRI. Understanding the psychological dimensions of recurrent FRIs is crucial for comprehensive patient care, and underscores the importance of integrating psychological support into the treatment paradigm for such cases.

[Non-unions of the upper extremities]

The diagnosis and treatment of non-unions still represents an interdisciplinary challenge. Therefore, prevention, early detection and specific treatment are of great importance. Non-unions of the upper extremities, although less common than that of the lower extremities, requires special attention for successful treatment due to the central role of the shoulder girdle and arm in day to day activities. Successful treatment of non-unions requires a comprehensive evaluation of the patient's medical history, a thorough clinical examination and in particular radiological imaging. In order to effectively treat the pseudarthrosis it is crucial to distinguish between pseudarthroses that are suspected to be due to infections and those that are not. This article presents a treatment algorithm for managing both pseudarthrosis due to infection and pseudarthrosis without infection in the upper extremities.

Enhancing antibacterial properties of titanium implants through a novel Ag-TiO2-OTS nanocomposite coating: a comprehensive study on resist-killing-disintegrate approach

Titanium (Ti) implants are widely used in orthopedic and dental applications due to their excellent biocompatibility and mechanical properties. However, bacterial adhesion and subsequent biofilm formation on implant surfaces pose a significant risk of postoperative infections and complications. Conventional surface modifications often lack long-lasting antibacterial efficacy, necessitating the development of novel coatings with enhanced antimicrobial properties. This study aims to develop a novel Ag-TiO2-OTS (Silver-Titanium dioxide-Octadecyltrichlorosilane, ATO) nanocomposite coating, through a chemical plating method. By employing a 'resist-killing-disintegrate' approach, the coating is designed to inhibit bacterial adhesion effectively, and facilitate pollutant removal with lasting effects. Characterization of the coatings was performed using spectroscopy, electron microscopy, and contact angle analysis. Antibacterial efficacy, quantitatively evaluated against E. coli and S. aureus over 168 h, showed a significant reduction in bacterial adhesion by 76.6% and 66.5% respectively, and bacterial removal rates were up to 83.8% and 73.3% in comparison to uncoated Ti-base material. Additionally, antibacterial assays indicated that the ratio of the Lifshitz-van der Waals apolar component to electron donor surface energy components significantly influences bacterial adhesion and removal, underscoring a tunable parameter for optimizing antibacterial surfaces. Biocompatibility assessments with the L929 cell line revealed that the ATO coatings exhibited excellent biocompatibility, with minimal cytotoxicity and no significant impact on cell proliferation or apoptosis. The ATO coatings provided a multi-functionality surface that not only resists bacterial colonization but also possesses self-cleaning capabilities, thereby marking a substantial advancement in the development of antibacterial coatings for medical implants.

Fracture-Related Infection of a Distal Femur Open Fracture Treated With a Supracutaneous Locking Plate

Fracture-related infection (FRI) is a challenging complication in open fractures. It can cause major disability to patients and a burden to the public health sector. A multidisciplinary approach is required to eradicate infection and improve the quality of life for patients. We present a case of an FRI in an open fracture of the distal femur treated using a supracutaneous locking plate, which is an uncommon technique. This technique yields excellent outcomes in controlling local infection and providing satisfactory stability, especially for a peri-articular distal femur fracture with FRI. Therefore, supracutaneous plating using a locking plate can be considered an alternative option to conventional external fixations in managing FRIs.

Pathogens in FRI - Do bugs matter? - An analysis of FRI studies to assess your enemy

Fracture-related infection (FRI) is a devasting complication for both patients and their treating Orthopaedic surgeon that can lead to loss of limb function or even amputation. The unique and unpredictable features of FRI make its diagnosis and treatment a significant challenge. It has substantial morbidity and financial implications for patients, their families and healthcare providers. In this article, we perform an in-depth and comprehensive review of FRI through recent and seminal literature to highlight evolving definitions, diagnostic and treatment approaches, focusing on common pathogens such as Staphylococcus aureus, polymicrobial infections and multi-drug-resistant organisms (MDRO). Furthermore, multiple resistance mechanisms and adaptations for microbial survival are discussed, as well as modern evidence-based medical and surgical advancements in treatment strategies in combating FRI.

Early Management for Fracture-Related Infection: A Literature Review

Fracture-related infections (FRIs), as shown in the literature, represent one of the main complications of trauma surgery. They are a consequence of an implant-related "biofilm" formation and are a challenge for surgeons, microbiologists, and infectious disease specialists. For a correct diagnosis, careful clinical evaluation, to look for signs/symptoms attributable to an infectious condition, and instrumental examinations, to highlight the site of infection, its extent, and its severity, are both essential. Unfortunately, due to the lack of data in the literature, there is no consensus about guidelines on the diagnosis and treatment of FRIs. The purpose of this study is to present an up-to-date concept evaluation of the diagnostic procedures and treatment options available in the management of fracture-related infections.

The global burden of fracture-related infection: can we do better?

Fracture-related infection is a major complication related to musculoskeletal injuries that not only has important clinical consequences, but also a substantial socioeconomic impact. Although fracture-related infection is one of the oldest disease entities known to mankind, it has only recently been defined and, therefore, its global burden is still largely unknown. In this Personal View, we describe the origin of the term fracture-related infection, present the available data on its global impact, and discuss important aspects regarding its prevention and management that could lead to improved outcomes in both high-resource and low-resource settings. We also highlight the need for health-care systems to be adequately compensated for the high cost of human resources (trained staff) and well-equipped facilities required to adequately care for these complex patients. Our aim is to increase awareness among clinicians and policy makers that fracture-related infection is a disease entity that deserves prioritisation in terms of research, with the goal to standardise treatment and improve patient outcomes on a global scale.

Efficacy of lysostaphin-coated titanium plates on implant-associated MRSA osteitis in minipigs

PURPOSE

The growing incidence of implant-associated infections (IAIs) caused by biofilm-forming Staphylococcus aureus in combination with an increasing resistance to antibiotics requires new therapeutic strategies. Lysostaphin has been shown to eliminate this biofilm. Own studies confirm the effectiveness in a murine model. The current study characterizes the effects of lysostaphin-coated plates in an IAI minipig model.

METHODS

The femur of 30 minipigs was stabilized with a five-hole plate, a bone defect was created, and in 20 cases methicillin-resistant Staphylococcus aureus was applied. Ten animals served as control group. After 14 days, local debridement, lavage, and plate exchange (seven-hole plate) were performed. Ten of the infected minipigs received an uncoated plate and 10 a lysostaphin-coated plate. On day 84, the minipigs were again lavaged, followed by euthanasia. Bacterial load was quantified by colony-forming units (CFU). Immunological response was determined by neutrophils, as well as interleukins. Fracture healing was assessed radiologically.

RESULTS

CFU showed significant difference between infected minipigs with an uncoated plate and minipigs with a lysostaphin-coated plate (p = 0.0411). The infection-related excessive callus formation and calcification was significantly greater in the infected animals with an uncoated plate than in animals with a lysostaphin-coated plate (p = 0.0164/p = 0.0033). The analysis of polymorphonuclear neutrophils and interleukins did not reveal any pioneering findings.

CONCLUSION

This study confirms the minipig model for examining IAI. Furthermore, coating of plates using lysostaphin could be a promising tool in the therapeutic strategies of IAI. Future studies should focus on coating technology of implants and on translation into a clinical model.

Diagnostic Role of Metagenomic Next-Generation Sequencing in Tubercular Orthopedic Implant-Associated Infection

Objective

The diagnosis of tubercular orthopedic implant-associated infection (TB-IAI) is challenging. This study evaluated the value of metagenomic next-generation sequencing (mNGS) for the diagnosis of TB-IAI and developed a standardized diagnostic procedure for TB-IAI.

Methods

The records of all patients with TB-IAI diagnosed and treated at our institution between December 2018 and September 2022 were retrospectively reviewed. Patient demographic characteristics, medical history, laboratory test, microbial culture, histopathology, and mNGS results, and time to diagnosis were recorded. The diagnostic efficiency of mNGS for TB-IAI was assessed by comparing the results and diagnostic time with that of other diagnostic modalities.

Results

Ten patients were included in the analysis, including eight with prosthetic joint infections and two with fracture-related infections. The mNGS positivity rate was 100% (10/10), which was higher than that of TB-antibody (11%, 1/9), real-time quantitative polymerase chain reaction (22%, 2/9), T-SPOT.TB (25%, 2/8), purified protein derivative (50%, 4/8), microbial culture (50%, 5/10), and histopathology (20%, 2/10). mNGS shortened the time to diagnosis of TB-IAI. A standardized diagnostic procedure for TB-IAI was developed based on the findings.

Conclusion

mNGS is useful for the diagnosis of TB-IAI. mNGS is recommended in cases where it is difficult to identify a pathogen using routine diagnostic tests. The standardized diagnostic procedure might improve TB-IAI diagnosis.

Importance

TB-IAI is a rare infection, which occurs after orthopedic surgery and hard to diagnose microbiologically. mNGS is a new detection technique not yet discussed in current literature as a means for TB-IAI diagnostics. Here we describe a cohort of patients with TB-IAI diagnosed by mNGS show high efficiency of mNGS for detection of this pathology and present a clinical algorithm supplementing conventional methods for TB-IAI assessment.

Mismatch Rate of Empirical Antimicrobial Treatment in Fracture-Related Infections

OBJECTIVES

To evaluate the current standard of care regarding empirical antimicrobial therapy in fracture-related infections (FRIs).

METHODS

DESIGN

Retrospective cohort study.

SETTING

Level I Trauma Center.

PATIENT SELECTION CRITERIA

Adult patients treated for FRI with surgical debridement and empirical antibiotics between September 1, 2014, and August 31, 2022. Patients were excluded if less than 5 tissue samples for culture were taken, culture results were negative, or there was an antibiotic-free window of less than 3 days before debridement.

OUTCOME MEASURES AND COMPARISONS

FRI microbial etiology, antimicrobial resistance patterns (standardized antimicrobial panels were tested for each pathogen), the mismatch rate between empirical antimicrobial therapy and antibiotic resistance of causative microorganism(s), and mismatching risk factors.

RESULTS

In total, 75 patients were included [79% (59/75) men, mean age 51 years]. The most prevalent microorganisms were Staphylococcus aureus (52%, 39/75) and Staphylococcus epidermidis (41%, 31/75). The most frequently used empirical antibiotic was clindamycin (59%, 44/75), followed by combinations of gram-positive and gram-negative covering antibiotics (15%, 11/75). The overall mismatch rate was 51% (38/75) [95% confidence interval (CI), 0.39-0.62] and did not differ between extremities [upper: 31% (4/13) (95% CI, 0.09-0.61), lower: 55% (33/60) (95% CI, 0.42-0.68, P = 0.11)]. Mismatching empirical therapy occurred mostly in infections caused by S. epidermidis and gram-negative bacteria. Combination therapy of vancomycin with ceftazidime produced the lowest theoretical mismatch rate (8%, 6/71). Polymicrobial infections were an independent risk factor for mismatching (OR: 8.38, 95% CI, 2.53-27.75, P < 0.001).

CONCLUSIONS

In patients with FRI, a mismatching of empirical antibiotic therapy occurred in half of patients, mainly due to lack of coverage for S. epidermidis , gram-negative bacteria, and polymicrobial infections. Empirical therapy with vancomycin and ceftazidime produced the lowest theoretical mismatch rates. This study showed the need for the consideration of gram-negative coverage in addition to standard broad gram-positive coverage. Future studies should investigate the effect of the proposed empirical therapy on long-term outcomes.

LEVEL OF EVIDENCE

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