The epidemiology of fracture-related infections in Germany

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.

Fracture-related infection blood-based biomarkers: Diagnostic strategies

Fracture-related infections are significant postoperative complications that carry substantial patient burden and additional healthcare costs. Despite their impact on outcome, early diagnosis of these infections remains challenging due to current available tests lacking acceptable diagnostic parameters. This review compiles existing information on blood-based biomarkers that have been evaluated as early diagnostic tools and highlights the challenges in their reliability. To begin to overcome these challenges new avenues of biomarker discovery utilizing "omics" technologies and novel analytical methods are being investigated in recent years. It appears that, despite their complexity, these newer approaches may be the future in biomarker discovery for fracture-related infection diagnosis.

Is there a role for suppression of infection in managing fracture-related infection following intra-medullary nailing?

BACKGROUND

The management of fracture-related infection has undergone radical progress following the development of international guidelines. However, there is limited consideration to the realities of healthcare in low-resource environments due to a lack of available evidence in the literature from these settings. Initial antimicrobial suppression to support fracture union is frequently used in low- and middle-income countries despite the lack of published clinical evidence to support its practice. This study aimed to evaluate the outcomes following initial antimicrobial suppression to support fracture union in the management of fracture-related infection.

METHODS

A retrospective review of consecutive patients treated with initial antimicrobial suppression to support fracture healing followed by definitive eradication surgery to manage fracture-related infections following intramedullary fixation was performed. Indications for this approach were; a soft tissue envelope not requiring reconstructive surgery, radiographic evidence of stable fixation with adequate alignment, and progression towards fracture union.

RESULTS

This approach was associated with successful treatment in 51/55 (93 %) patients. Fracture union was achieved in 52/55 (95 %) patients with antimicrobial suppression alone. Remission of infection was achieved in 54/55 (98 %) patients following definitive infection eradication surgery. Following antibiotic suppression, 6/46 (13 %) pathogens isolated from intra-operative samples demonstrated multi-drug resistance.

CONCLUSION

Initial antimicrobial suppression to support fracture healing followed by definitive infection eradication surgery was associated with successful treatment in 93 % of patients. The likelihood of remission of infection increases when eradication surgery is performed in a healed bone. This approach was not associated with an increased risk of developing multi-drug-resistant infections compared to contemporary bone infection cohorts in the published literature.

LEVEL OF EVIDENCE

IV.

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.

Acute prophylactic antibiotic nailing of open femoral shaft fractures for prevention of fracture-related infection

Background

Open, grossly contaminated femoral shaft fractures pose a significant threat for fracture-related infection. Traditional treatment for these injuries consists of irrigation and debridement with temporizing external fixation placement and staged conversion to definitive fixation.

Methods

We describe a protocol for acute antibiotic cement nailing of open femoral shaft fractures as an infection prophylaxis modality in fractures with a high risk of infection and present three cases.

Results

Three patients presented with open femoral shaft fractures with large soft tissue defects and gross contamination and were successfully treated with acute retrograde antibiotic nailing and external fixation with later conversion to definitive metallic nailing. They did not develop infection and had acceptable postoperative function and fracture alignment.

Conclusion

This technique of early infection prophylaxis after open femoral shaft fracture is reproducible, pragmatic, and cost-effective.

Time to Positivity in Blood Culture Bottles Inoculated with Sonication Fluid from Fracture-Related Infections

The timely and accurate identification of causative agents is crucial for effectively managing fracture-related infections (FRIs). Among various diagnostic methods, the "time to positivity" (TTP) of cultures has emerged as a valuable predictive factor in infectious diseases. While sonication of implants and inoculation of blood culture bottles with sonication fluid have enhanced sensitivity, data on the TTP of this microbiological technique remain limited. Therefore, patients with ICM criteria for confirmed FRI treated at our institution between March 2019 and March 2023 were retrospectively identified and their microbiological records were analyzed. The primary outcome parameter was TTP for different microorganism species cultured in a liquid culture collected from patients with confirmed FRI. A total of 155 sonication fluid samples from 126 patients (average age 57.0 ± 17.4 years, 68.3% males) was analyzed. Positive bacterial detection was observed in 78.7% (122/155) of the liquid culture pairs infused with sonication fluid. Staphylococcus aureus was the most prevalent organism (42.6%). Streptococcus species exhibited the fastest TTP (median 11.9 h), followed by Staphylococcus aureus (median 12.1 h) and Gram-negative bacteria (median 12.5 h), all of which had a 100% detection rate within 48 h after inoculation. Since all Gram-negative pathogens yielded positive culture results within 24 h, it could be discussed if empirical antibiotic therapy could be de-escalated early and limited towards the Gram-positive germ spectrum if no Gram-negative pathogens are detected up to this time point in the context of antibiotic stewardship.

Implant retention in a rabbit model of fracture-related infection

Aims

Fracture-related infection (FRI) is commonly classified based on the time of onset of symptoms. Early infections (< two weeks) are treated with debridement, antibiotics, and implant retention (DAIR). For late infections (> ten weeks), guidelines recommend implant removal due to tolerant biofilms. For delayed infections (two to ten weeks), recommendations are unclear. In this study we compared infection clearance and bone healing in early and delayed FRI treated with DAIR in a rabbit model.

Methods

Staphylococcus aureus was inoculated into a humeral osteotomy in 17 rabbits after plate osteosynthesis. Infection developed for one week (early group, n = 6) or four weeks (delayed group, n = 6) before DAIR (systemic antibiotics: two weeks, nafcillin + rifampin; four weeks, levofloxacin + rifampin). A control group (n = 5) received revision surgery after four weeks without antibiotics. Bacteriology of humerus, soft-tissue, and implants was performed seven weeks after revision surgery. Bone healing was assessed using a modified radiological union scale in tibial fractures (mRUST).

Results

Greater bacterial burden in the early group compared to the delayed and control groups at revision surgery indicates a retraction of the infection from one to four weeks. Infection was cleared in all animals in the early and delayed groups at euthanasia, but not in the control group. Osteotomies healed in the early group, but bone healing was significantly compromised in the delayed and control groups.

Conclusion

The duration of the infection from one to four weeks does not impact the success of infection clearance in this model. Bone healing, however, is impaired as the duration of the infection increases.

[Importance of local antibiotics in the prophylaxis and treatment of fracture-associated infections]

BACKGROUND

Fracture-associated infections (FRI) are a severe complication that lead to higher morbidity and high costs for the healthcare system. An effective prophylaxis and treatment of FRI are therefore of great interest.

OBJECTIVE

The aim of this review is to summarize the available evidence on the use of local antibiotics for the prophylaxis and treatment of FRI.

MATERIAL AND METHODS

A thorough search and a narrative synthesis of the available literature were performed. Their depiction is supplemented by an illustrative presentation of a case report.

RESULTS

A robust consensus definition of FRI has existed since 2018. The current use of local antibiotics for the prophylaxis and treatment of FRI in Germany is heterogeneous. There is no consensus on local antibiotic treatment of FRI. The available literature shows an advantage for the additive local antibiotic treatment of open fractures. In closed fractures there is a tendency towards an advantage especially in the presence of further risk factors (long duration of external fixation, higher degree of closed tissue damage, compartment syndrome). According to analogous data from the field of endoprosthetics, additive local antibiotic treatment could also be advantageous under closed soft tissue conditions. The evidence is insufficient to enable the recommendation for a specific antibiotic or a specific mode of application. Local and systemic adverse reactions are frequently discussed in the literature but their incidence is low.

CONCLUSION

Overall, additive local antibiotic treatment is to be recommended for open fractures and in closed fractures in the presence of other risk factors. Local and systemic adverse reactions as well as the development of antibiotic resistance must be weighed up in individual cases.

Fracture-Related Infection-Epidemiology, Etiology, Diagnosis, Prevention, and Treatment

BACKGROUND

Fracture-related infection (FRI) is a challenge to physicians and other workers in health care. In 2018, there were 7253 listed cases of FRI in Germany, corresponding to an incidence of 10.7 cases per 100 000 persons per year.

METHODS

This review is based on pertinent publications retrieved from a search in PubMed with the search terms "fracture," "infection," "guideline," and "consensus." Aside from the primary literature, international guidelines and consensus recommendations were evaluated as well.

RESULTS

FRI arise mainly from bacterial contamination of the fracture site. Staphylococcus aureus is the most commonly detected pathogen. The treatment is based on surgery and antibiotics and should be agreed upon by an interdisciplinary team; it is often difficult because of biofilm formation. Treatment options include implant-preserving procedures and single-stage, two-stage, or multi-stage implant replacement. Treatment failure occurs in 10.3% to 21.4% of cases. The available evidence on the efficacy of various treatment approaches is derived mainly from retrospective cohort studies (level III evidence). Therefore, periprosthetic joint infections and FRI are often discussed together.

CONCLUSION

FRI presents an increasing challenge. Preventive measures should be optimized, and the treatment should always be decided upon by an interdisciplinary team. Only low-level evidence is available to date to guide diagnostic and treatment decisions. High-quality studies are therefore needed to help us meet this challenge more effectively.

A population-based epidemiological and health economic analysis of fracture-related infection

Aims

The aim of this study was to perform the first population-based description of the epidemiological and health economic burden of fracture-related infection (FRI).

Methods

This is a retrospective cohort study of operatively managed orthopaedic trauma patients from 1 January 2007 to 31 December 2016, performed in Queensland, Australia. Record linkage was used to develop a person-centric, population-based dataset incorporating routinely collected administrative, clinical, and health economic information. The FRI group consisted of patients with International Classification of Disease 10th Revision diagnosis codes for deep infection associated with an implanted device within two years following surgery, while all others were deemed not infected. Demographic and clinical variables, as well as healthcare utilization costs, were compared.

Results

There were 111,402 patients operatively managed for orthopaedic trauma, with 2,775 of these (2.5%) complicated by FRI. The development of FRI had a statistically significant association with older age, male sex, residing in rural/remote areas, Aboriginal or Torres Strait Islander background, lower socioeconomic status, road traffic accident, work-related injuries, open fractures, anatomical region (lower limb, spine, pelvis), high injury severity, requiring soft-tissue coverage, and medical comorbidities (univariate analysis). Patients with FRI had an eight-times longer median inpatient length of stay (24 days vs 3 days), and a 2.8-times higher mean estimated inpatient hospitalization cost (AU$56,565 vs AU$19,773) compared with uninfected patients. The total estimated inpatient cost of the FRI cohort to the healthcare system was AU$156.9 million over the ten-year period.

Conclusion

The results of this study advocate for improvements in trauma care and infection management, address social determinants of health, and highlight the upside potential to improve prevention and treatment strategies.

Treatment of Fracture-Related Infection after Pelvic Fracture

BACKGROUND

The management of pelvic fractures is a significant challenge. Surgical site infection can result in the need for revision surgery, cause functional impairment, and lead to a prolonged length of stay and increased treatment costs. Although reports on fracture-related infection (FRI) after pelvic fracture fixation are sparsely reported in the literature, it is a serious complication. This study analysed patients with FRIs after pelvic fracture regarding patient characteristics, treatment strategies, and an evaluation of risk factors for FRI.

METHODS

In this retrospective single-centre study, FRI was diagnosed based on clinical symptoms of infection and a positive culture of a bacterial infection. Depending on the severity and acuteness of the infection, osseous stabilization was restored either via implant retention (stable implant, no osteolysis), exchange (loose implant or bony defect), or external fixation (recurrence of infection after prior implant retaining revision). Healing of infection was defined as no sign of recurring infection upon clinical, radiological, and laboratory examination in the last follow-up visit.

RESULTS

The FRI rate in our patient population was 7.5% (24/316). In 8/24 patients, the FRI occurred within the first three weeks after initial surgery (early) and 16/24 presented with a late onset of symptoms of FRI. A strategy of debridement, antibiotics, and implant retention (DAIR) was successful in 9/24 patients with FRI after pelvic fracture. A total of 10 patients required an exchange of osteo-synthetic implants, whereof three were exchanged to an external fixator. In five patients, we removed the implant because the fracture had already consolidated at the time of revision for infection. A total of 17/24 patients had a poly-microbial infection after a pelvic fracture and 3/24 patients died from post-traumatic multi-organ failure within the first 6 months after trauma. There were no cases of persistent infection within the remaining 21 patients.

CONCLUSIONS

Although poly-microbial infection is common in FRI after pelvic fracture, the recurrence rate of infection is relatively low. A complex pelvic trauma with significant soft tissue injury is a risk factor for recurrent infection and multiple revisions. A strategy of DAIR can be successful in patients with a stable implant. In cases with recurrent infection or an unstable fracture site, the exchange of implants should be considered.

[Antibiotic use for prophylaxis and empirical therapy of fracture-related infections in Germany : A survey of 44 hospitals]

BACKGROUND

Antibiotics play an important role in the prophylaxis and treatment of infections in orthopedic trauma surgery; however, there seems to be remarkable differences in the clinical antibiotic practice between hospitals, particularly for open fractures and for the empirical therapy of fracture-related infections (FRI).

METHODS

Therefore, we intended to evaluate the current clinical praxis in university and workers' compensation hospitals in Germany with a questionnaire on prophylaxis and empirical treatment of FRI. The results were compared with the resistance profile of 86 FRI patients in order to analyze the hypothetical effectiveness of the empirical treatment.

RESULTS

A total of 44 hospitals (62.0%) responded. A homogeneous antibiotic prophylaxis (95.5% of all hospitals) with cephalosporins was reported for perioperative prophylaxis of internal fixation of closed fractures. For open fractures, eight different monotherapy and combination treatment concepts were reported. In empirical treatment of FRI, 12 different therapeutic concepts were reported, including aminopenicillins/beta lactamase inhibitors (BLI) (31.8%), cephalosporins (31.8%), and ampicillin/sulbactam + vancomycin (9.1%). In terms of the hypothetical effectiveness of these antibiotic regimes, low sensitivity rates of 65.1% and 74.4% for cephalosporins and aminopenicillins/BLI, respectively, were found. For the combination vancomycin + meropenem, the highest hypothetical sensitivity (91.9%) was detected.

DISCUSSION

Based on the existing, institution-specific pathogen spectrum, the combination therapy including meropenem and vancomycin seems to be of value but should be restricted to patients with multiple revision procedures or a septic course of infection in order to prevent the selection of highly resistant pathogens.

The antibiotic bead pouch - a useful technique for temporary soft tissue coverage, infection prevention and therapy in trauma surgery

Soft tissue defects resulting from trauma and musculoskeletal infections can complicate surgical treatment. Appropriate temporary coverage of these defects is essential to achieve the best outcomes for necessary plastic soft tissue defect reconstruction. The antibiotic bead pouch technique is a reasonable surgical approach for managing temporary soft tissue defects following adequate surgical debridement. This technique involves the use of small diameter antibiotic-loaded bone cement beads to fill the dead space created by debridement. By applying antibiotics to the bone cement and covering the beads with an artificial skin graft, high local dosages of antibiotics can be achieved, resulting in the creation of a sterile wound that offers the best starting position for soft tissue and bone defect reconstruction. This narrative review describes the rationale for using this technique, including its advantages and disadvantages, as well as pearls and pitfalls associated with its use in daily practice. In addition, the article provides a comprehensive overview of the literature that has been published since the technique was introduced in surgical practice.

Hydrogel Delivery of DNase I and Liposomal Vancomycin to Eradicate Fracture-related Methicillin-resistant Staphylococcus aureus Infection and Support Osteoporotic Fracture Healing

Fracture-related infection (FRI) is a devastating complication in orthopedic surgery. A recent study showed that FRI causes more severe infection and further delays healing in osteoporotic bone. Moreover, bacterial biofilm formed on implants cannot be eradicated by systemic antibiotics, warranting novel treatments. Here, we developed a DNase I and Vancomycin hydrogel delivery vehicle to eradicate Methicillin-resistant Staphylococcus aureus (MRSA) infection in vivo. Vancomycin was encapsulated in liposomes, and DNase I and Vancomycin/liposomal-Vancomycin was loaded on thermosensitive hydrogel. In vitro drug release test showed a burst release of DNase I (77.2%) within 72 hours and sustained release of Vancomycin (82.6%) up to day 14. The in vivo efficacy was evaluated in a clinically relevant ovariectomy (OVX) induced osteoporotic metaphyseal fracture model with MRSA infection, and a total of 120 Sprague Dawley rats were used. In the OVX with infection group, biofilm development caused a drastic inflammatory response, trabecular bone destruction, and non-union. In the DNase I and Vancomycin co-delivery hydrogel group (OVX-Inf-DVG), bacteria on bone and implant were eradicated. X-ray and micro-CT showed preservation of trabecular bone and bone union. HE staining showed the absence of inflammatory necrosis, and fracture healing was restored. The local elevation of TNF-α and IL-6 and increased number of osteoclasts were prevented in the OVX-Inf-DVG group. Our findings suggest that dual release of DNase I and Vancomycin initially followed by Vancomycin only later up to 14 days effectively eliminates MRSA infection, prevents biofilm development and provides a sterile environment to promote fracture healing in osteoporotic bone with FRI. STATEMENT OF SIGNIFICANCE: The biofilm formation on the implant is difficult to eradicate, causing recurrent infection and non-union in fracture-related infection (FRI). Here we developed a hydrogel therapy with high in vivo efficacy to eliminate MRSA biofilm infection in a clinically-relevant FRI model in osteoporotic bone. By loading DNase I and vancomycin/liposomal-vancomycin on thermosensitive poly-(DL-lactic acidco-glycolic acid) (PLGA)-polyethylene glycol (PEG)-PLGA hydrogel, a dual release of DNase I and Vancomycin was achieved whilst preserving enzyme activity. In this model, the progressive development of infection caused a drastic inflammatory response, osteoclastogenesis, trabecular bone destruction, and non-union of fracture. These pathological changes were successfully prevented by the dual delivery of DNase I and vancomycin. Our findings provide a promising strategy for FRI in osteoporotic bone.

Wound alpha defensin levels are significantly higher in patients with fracture related infection: A pilot, prospective cohort study

BACKGROUND

In absence of frank purulence, wound cultures represent 'gold-standard' for diagnosis of fracture related infection (FRI). However, these are time-intensive, and may be falsely negative, necessitating the need for accurate and rapid biomarker-based diagnosis. We conducted this study to determine the accuracy of 3 wound-based biomarkers for the diagnosis of FRI.

METHODS

This was a prospective cohort study on adult patients who underwent an operative procedure for an upper or lower limb fracture. Wound fluid levels of alpha-defensin (AD), neutrophil elastase (NE) and IL-6 were evaluated on post-operative day 2, and patients were followed up for one month. Patients were categorized as cases (FRI) or controls (no FRI), on the basis of the consensus definition of FRI. Univariate analysis, along with receiver operating characteristic (ROC) analysis was performed.

RESULTS

48 patients were included. AD levels showed a 2.6-fold elevation in cases (n = 26, Median = 23.74 µg/ml) as compared to controls (n = 22, Median = 8.78 µg/ml). The area under the curve for this variable was 0.71 (95% Confidence Intervals = 0.56 - 0.86). The levels of NE and IL-6 were not significantly different between cases and controls.

CONCLUSION

Wound AD levels are significantly elevated in patients with FRI. However, these results need to be validated in a larger cohort of patients before it can be used as a biomarker of FRI.

Antibiotic-Loaded Coatings to Reduce Fracture-Related Infections: Retrospective Case Series of Patients with Increased Infectious Risk

Local antibiotic delivery strategies have been increasingly employed for the prevention of fracture-related infections (FRIs). The aim of this study is to evaluate the efficacy and safety of antibiotic-coated implants in the prevention of FRIs after surgical treatment in patients with increased infectious risk. A retrospective observational study has been conducted on patients with upper and lower limb fractures treated with internal fixation or prosthetic replacements, using a gentamicin coated nail (CN) and/or antibiotic-loaded hydrogel applied to the implant of choice (ALH). The study included 37 patients (20 M, 17 F), with a mean age of 63 years. The mean estimated preoperative infectious risk score was 6.4%. ALH was used in 27 cases, tibial CNs were implanted in 4 cases, and both were employed in 6 cases. The antibiotics used locally were gentamicin in 72.97% of cases (27 patients) and a combination of gentamicin + vancomycin in 27.03% of cases (10 patients). Mean follow-up was 32 months. Only one case (2.94%) showed onset of FRI at 5 months after surgery. Local antibiotic prophylaxis by coating resulted in a reduction in the incidence FRI, as compared to the estimated preoperative risk. The use of ALH allows for the choice of antibiotic; however, the application of antibiotics seems more nonuniform when applied to a nail.

Multidisciplinary Treatment of Fracture-Related Infection Has a Positive Impact on Clinical Outcome-A Retrospective Case Control Study at a Tertiary Referral Center

OBJECTIVES

Fracture-related infection (FRI) is a major complication in orthopedic and trauma surgery. The management and choice of treatment can be difficult depending on multiple factors. Therefore, we implemented a weekly multidisciplinary team discussion to determine diagnostic and treatment strategies in FRI patients and aimed to analyze its effect on clinical outcomes.

METHODS

Clinical outcomes of FRI patients treated before and after implementation of a structured multidisciplinary treatment (MDT) approach with a weekly case discussion were compared at a follow-up of 12 months.

RESULTS

In total, n = 117 were eligible for enrolment, whereby n = 58 patients (72.4% male, mean age 56.7 ± 16.8 years) constituted the MDT group and n = 59 patients (72.9% male, mean age 55.0 ± 16.5 years) the control group. In the MDT group more cases were treated with local antibiotics (67.2% vs. 27.1%, p < 0.001) and significant less amputations (3.4% vs. 6.8%, p = 0.014), as well as less revision surgeries (1.5 ± 1.2 (0-5) vs. 2.2 ± 1.2 (0-7), p = 0.048) were performed. A trend towards less debridement, antibiotics and implant retention (DAIR) procedures, lower rates of recurrence of infection and less treatment failures in the MDT group was observable, even though not statistically significant.

CONCLUSION

An MDT approach providing a patient tailored treatment concept in the treatment of FRI patients appears to be beneficial for the affected patients. Quality and efficacy of implemented MDT meetings should further be evaluated to provide sufficient evidence to further implement this valuable tool in clinical practice and decision making.

Vancomycin-nanofunctionalized peptide-enriched silk fibroin to prevent methicillin-resistant Staphylococcus epidermidis-induced femoral nonunions in rats

Introduction

Implant-related infections and infected fractures are significant burdens in orthopedics. Staphylococcus epidermidis is one of the main causes of bone infections related to biofilm formation upon implants. Current antibiotic prophylaxis/therapy is often inadequate to prevent biofilm formation and results in antibiotic resistance. The development of bioactive materials combining antimicrobial and osteoconductive properties offers great potential for the eradication of microorganisms and for the enhancement of bone deposition in the presence of infections. The purpose of this study is to prevent the development of methicillin-resistant S. epidermidis (MRSE)-infected nonunion in a rat model.

Methods

To this end, a recently developed in our laboratories bioactive material consisting of antibiotic-loaded nanoparticles based on carboxylic acid functionalized hyperbranched aliphatic polyester (CHAP) that are integrated into peptide-enriched silk fibroin sponges with osteoconductive properties (AFN-PSF) was employed, whose biocompatibility and microbiological tests provided proof of its potential for the treatment of both orthopedic and dental infections. In particular, non-critical femoral fractures fixed with plates and screws were performed in Wistar rats, which were then randomly divided into three groups: 1) the sham control (no infection, no treatment); 2) the control group, infected with MRSE and treated with peptide-enriched silk fibroin sponges incorporating non-drug-loaded functionalized nanoparticles (PSF); 3) the treated group, infected with MRSE and treated with peptide-enriched silk fibroin sponges incorporating vancomycin-loaded functionalized nanoparticles (AFN-PSF). After 8 weeks, bone healing and osteomyelitis were clinically assessed and evaluated by micro-CT, microbiological and histological analyses.

Results

The sham group showed no signs of infection and complete bone healing. The PSF group failed to repair the infected fracture, displaying 75% of altered bone healing and severe signs of osteomyelitis. The AFN-PSF treated group reached 70% of fracture healing in the absence of signs of osteomyelitis, such as abscesses in the cortical and intraosseous compartments and bone necrosis with sequestra.

Discussion

AFN-PSF sponges have proven effective in preventing the development of infected nonunion in vivo. The proposed nanotechnology for local administration of antibiotics can have a significant impact on patient health in the case of orthopedic infections.

The management of fracture related infections: What practices can be supported by high-level evidence?

Fracture related infections (FRIs) are a disabling condition causing significant concern within the orthopaedic community. FRIs have a huge societal and economic burden leading to prolonged recovery times and the potential for becoming chronic conditions or being life-threatening. Despite its importance in our field, the surgical community has just recently agreed on a definition which, added to the lack of surgical trials assessing preventive and treatment interventions have limited our understanding and precipitated wide variations in surgeons' practice. This article aims to review the current practices that can be supported with high-quality evidence. Currently, we have a limited body of high-quality evidence on FRI prevention and treatment. A handful of measures have proven effective, such as the use of prophylactic antibiotics, the use of saline and low pressure as the preferred irrigation solution and the safety of delaying initial surgical débridement more than 6 hours without impacting infection rates for open fracture wounds débridement. Future multicentre trials, properly powered, will shed light on current areas of controversy regarding the benefit of different preoperative and perioperative factors for the prevention and treatment of FRIs. Higher quality evidence is needed to guide surgeons to offer an evidence-based approach to prevent FRI occurrence and to treat patients suffering from them.

Microbiology of fracture related infections

Fracture related infection remains a challenging complication that creates a heavy burden for orthopaedic trauma patients, their families, treating physicians and healthcare systems. Even current curative approaches (radical debridement, revision surgery and long-term antibiotics) often result in significant socioeconomic costs and the risk of life-long functional impairment to the patient. The prevalence of osteomyelitis due to trauma and surgical complications does not seem to be diminishing in our society and the emergence of antimicrobial resistance is a major health related concern with global relevance. Despite multi-drug resistant bacteria being on the rise universally, perioperative antibiotic prophylaxis in orthopaedic trauma care has only slightly changed in the last 25 years. Staphylococcus infections remain an increasing global concern, partially due to the resistance mechanisms developed by staphylococci to evade the host immune system and antibiotic treatment, and as such antibiotics are becoming increasingly ineffective. This paper will address fracture related infections in trauma patients, looking at the bacteriology of these infections, its clinical implications and evolving nature.

Antibiotic coated nails: Rationale, development, indications and outcomes

The concept of antibiotic-coated implants, mainly coated intramedullary nails, has become increasingly used for the treatment of fracture related infections. After a long period of hand-made implants, commercially fabricated implants combine several benefits. Antibiotic-coated nails constitute a solid treatment option for unstable diaphyseal infections with fractures or non-unions. They release high concentrations of antibiotics locally, while retaining reduction and providing axial stability. This review aims to provide an overview about the background, the development, the indications, the treatment strategies and the outcomes of antibiotic-coated intramedullary nails.

Epidemiology and outcomes of bone and joint infections in solid organ transplant recipients

Bone and joint infection (BJI) epidemiology and outcomes in solid organ transplant recipients (SOTr) remain largely unknown. We aim to describe BJI in a multi-center cohort of SOTr (Swiss Transplant Cohort Study). All consecutive SOTr with BJI (01.05.2008-31.12.2019) were included. A nested case-control study to identify risk factors for BJI was performed. Among 4482 patients, 61 SOTr with 82 BJI were included, at an incidence of 1.4% (95% CI 1.1-1.7), higher in heart and kidney-pancreas SOTr (Gray's test p < .01). Although BJI were predominately late events (median of 18.5 months post-SOT), most infections occurred during the first year post-transplant in thoracic SOTr. Diabetic foot osteomyelitis was the most frequent infection (38/82, 46.3%), followed by non-vertebral osteomyelitis (26/82, 31.7%). Pathogens included Gram-positive cocci (70/131, 53.4%), Gram-negative bacilli (34/131, 26.0%), and fungi (9/131, 6.9%). BJI predictors included male gender (OR 2.94, 95% CI 1.26-6.89) and diabetes (OR 2.97, 95% CI 1.34-6.56). Treatment failure was observed in 25.9% (21/81) patients and 1-year mortality post-BJI diagnosis was 14.8% (9/61). BJI remain a rare event in SOTr, associated with subtle clinical presentations, high morbidity and relapses, requiring additional studies in the future.

Quality of life after fracture-related infection of the foot

BACKGROUND

Fracture related infection (FRI) of the foot is a serious hazard. Despite successful therapy, the physiological and psychological involvement seems to be high. Therefore, we aim to analyze the impact of an FRI of the foot on the quality of life after successful surgical therapy and infect eradication.

METHODS

In total, 25 patients from two German hospitals treated for FRI of the foot between March 2011 to January 2020 were retrospectively included. Quality of life was assessed by the German Short Form 36 (SF-36) and the EuroQol five-dimension three-level questionnaire (EQ-5D) as well as the ICD-10 based psychological symptom rating (ISR), and compared to a norm obtained from the general population of Germany.

RESULTS

3.0 years (range 0.7-7.9 years) following final surgery after fracture-related infection of the foot, the mean physical health component score (PCS) of the SF-36 was 35.6 ± 12.3, and the mean mental health component score (MCS) of the SF-36 reached a value of 41.3 ± 12.9. Both values were significantly lower than in the general population of Germany (p< .019). The mean scores of the ISR of the cohort crossed the threshold of mild symptom burden in total, as well as for the subscales depression and somatization. The mean EQ-5D VAS rating (62.1 ± 18.6) and the EQ-5D index value (0.66 ± 0.27) were significantly lower in comparison to a score of 72.9 ± 1.0 and 0.88 obtained from an age-matched reference population (p < .01).

CONCLUSION

FRI of the foot represents a major burden for the patient. Physical and mental well-being of affected patients is restricted albeit successful treatment in terms of infect eradication and bone union has been achieved after a mean follow-up of 3.0 years. A patient-centered treatment approach focusing on improvement of quality of life during and after treatment is therefore warranted.

The State of Research in Fracture-Related Infection—A Bibliometric Analysis

Background and Objectives: Fracture-related infection (FRI) is a challenging complication in trauma surgery. A consensus definition of FRI has only recently been published. Therefore, the purpose of this study was to evaluate the state of research related to FRI. Material and Methods: A systemic literature review was conducted on research on FRI published between 2017 and 2020. The Web of Science database was used, and a bibliometric analysis was performed. To provide robust evidence regarding the impact of publications, the behavior of publications in non-traditional dissemination channels was analyzed. For this, the Research Interest Score and the Altmetric Score were combined. The Research Interest Score was calculated from information extracted from ResearchGate, while Altmetric Score includes information from different websites and apps with a significant volume of traffic, such as Twitter. Results: A total of 131 published papers were identified. The most significant contribution came from the United States and European countries. The most relevant articles were published by the journal Injury—International Journal of the Care of the Injured. A positive correlation was observed between the number of citations and Research Interest Scores, whereas the number of citations and Altmetric Score showed no correlation. The social media platform most used by FRI researchers was Twitter. Conclusions: By evaluating the status of publications for FRI between 2017 and 2020, an upward trend in the number of publications was evident. This could be related to the increasing acceptance of the long-needed definition for FRI and the implications it carries for daily clinical practice.

Evaluation of Comorbidities as Risk Factors for Fracture-Related Infection and Periprosthetic Joint Infection in Germany

Introduction: Fracture-related infections (FRI) and periprosthetic joint infections (PJI) represent a major challenge in orthopedic surgery. Incidence of both entities is annually growing. Comorbidities play an important role as an influencing factor for infection and thus, for prevention and treatment strategies. The aims of this study were (1) to analyze the frequency of comorbidities in FRI and PJI patients and (2) to evaluate comorbidities as causative risk factor for PJI and FRI. Methods: This retrospective cohort study analysed all ICD-10 codes, which were coded as secondary diagnosis in all in hospital-treated FRI and PJI in the year 2019 in Germany provided by the Federal Statistical Office of Germany (Destatis). Prevalence of comorbidities was compared with the prevalence in the general population. Results: In the year 2019, 7158 FRIs and 16,174 PJIs were registered in Germany, with 68,304 comorbidities in FRI (mean: 9.5 per case) and 188,684 in PJI (mean: 11.7 per case). Major localization for FRI were infections in the lower leg (55.4%) and forearm (9.2%), while PJI were located mostly at hip (47.4%) and knee joints (45.5%). Mainly arterial hypertension (FRI: n = 3645; 50.9%—PJI: n = 11360; 70.2%), diabetes mellitus type II (FRI: n = 1483; 20.7%—PJI: n = 3999; 24.7%), obesity (FRI: n = 749; 10.5%—PJI: n = 3434; 21.2%) and chronic kidney failure (FRI: n = 877; 12.3%—PJI: n = 3341; 20.7%) were documented. Compared with the general population, an increased risk for PJI and FRI was reported in patients with diabetes mellitus (PJI: 2.988; FRI: 2.339), arterial hypertension (PJI: 5.059; FRI: 2.116) and heart failure (PJI: 6.513; FRI: 3.801). Conclusion: Patients with endocrinological and cardiovascular diseases, in particular associated with the metabolic syndrome, demonstrate an increased risk for orthopedic implant related infections. Based on the present results, further infection prevention and treatment strategies should be evaluated.

The epidemiology and direct healthcare costs of aseptic nonunions in Germany - a descriptive report

Aims

This observational cross-sectional study aimed to answer the following questions: 1) how has nonunion incidence developed from 2009 to 2019 in a nationwide cohort; 2) what is the age and sex distribution of nonunions for distinct anatomical nonunion localizations; and 3) how high were the costs for surgical nonunion treatment in a level 1 trauma centre in Germany?

Methods

Data consisting of annual International Classification of Diseases (ICD)-10 diagnosis codes from German medical institutions from 2009 to 2019, provided by the Federal Statistical Office of Germany (Destatis), were analyzed. Nonunion incidence was calculated for anatomical localization, sex, and age groups. Incidence rate ratios (IRRs) were determined and compared with a two-sample z-test. Diagnosis-related group (DRG)-reimbursement and length of hospital stay were retrospectively retrieved for each anatomical localization, considering 210 patients.

Results

In 2019, a total of 11,840 nonunion cases (17.4/100,000 inhabitants) were treated. In comparison to 2018, the incidence of nonunion increased by 3% (IRR 1.03, 95% confidence interval (CI) 0.53 to 1.99, p = 0.935). The incidence was higher for male cases (IRR female/male: 0.79, 95% CI 0.76 to 0.82, p = 0.484). Most nonunions occurred at the pelvic and hip region (3.6/100,000 inhabitants, 95% CI 3.5 to 3.8), followed by the ankle and foot as well as the hand (2.9/100,000 inhabitants each). Mean estimated DRG reimbursement for in-hospital treatment of nonunions was highest for nonunions at the pelvic and hip region (€8,319 (SD 2,410), p < 0.001).

Conclusion

Despite attempts to improve fracture treatment in recent years, nonunions remain a problem for orthopaedic and trauma surgery, with a stable incidence throughout the last decade.

Cite this article: Bone Joint Res 2022;11(8):541–547.

Epidemiology and Drug Resistance of Fracture-Related Infection of the Long Bones of the Extremities: A Retrospective Study at the Largest Trauma Center in Southwest China

Objective

To describe the demographic characteristics, risk factors, and bacterial resistance of fracture-related infection (FRI) of the long bones of the extremities.

Materials and Methods

This single-center study retrospectively evaluated patients with FRI of the long bones of the extremities at West China Hospital between January 2012 and December 2017, and analyzed the demographic characteristics, risk factors, distribution of pathogenic bacteria, and bacterial drug resistance.

Results

Among 9,900 patients, 535 patients (5.4%) were diagnosed with FRI. The most common site of FRI was tibiofibular (298, 55.7%), with 424 cases (79.2%) of open fractures, and 282 cases (52.7%) due to traffic injuries. The 41–50 years age group had the highest incidence of FRI with 157 (29.3%) cases. Overall, 546 strains of 52 types of bacteria were detected in FRI patients, with 105 strains of multidrug-resistant (MDR) bacteria. Methicillin-resistant Staphylococcus aureus (48, 8.8%) and extended-spectrum-β-lactamase Escherichia coli (32, 5.8%) accounted for the largest proportion. Multivariate logistic regression analysis showed that sex (odds ratio [OR] 1.813; 95% confidence interval [CI], 1.071∼3.070; P = 0.027) and fracture type (OR 3.128; 95% CI, 1.683∼5.815; P < 0.001) were independent risk factors for monomicrobial infection (MI). Female sex (OR 4.190; 95% CI, 1.212∼14.486; P = 0.024) was an independent risk factor for polymicrobial infection (PI).

Conclusion

This study clarified the infection rates, changes in the bacterial spectrum, and drug resistance characteristics, and risk factors of FRI of the long bones of the extremities in the largest trauma center in southwest China.

Prevalence of psychological comorbidities in bone infection

OBJECTIVE

Bone infections represent a major complication in orthopedic and trauma surgery. Concomitant psychological disorders can significantly influence treatment outcomes. However, these are often overlooked. Therefore, we aimed to determine the nationwide epidemiology of fracture-related infection (FRI) and osteomyelitis in combination with psychological comorbidities.

METHODS

A dataset provided by the Federal Statistical Office (Destatis) consisting of annual, Germany-wide ICD-10 diagnosis codes from 2009 to 2019 was analysed. Incidences of the codes "T84.6, infection and inflammatory reaction due to internal fixation device" and "M86.-, osteomyelitis" were quantified. Proportions of secondary diagnoses of the chapter F of the ICD-10 were determined.

RESULTS

Incidences were 19.1/100,000 inhabitants for osteomyelitis and 10.5/100,000 inhabitants for FRI. Patients with psychological comorbidities constituted 14.6% of osteomyelitis cases and 26.5% of FRI cases, respectively. Between 2009 through 2019, the proportion of patients with a concomitant "F" diagnoses of the ICD-10 increased by 27.3% for osteomyelitis and by 24.1% for FRI. Most prevalent secondary diagnoses were organic, including symptomatic, mental disorders (F0), affective disorder (F3) and mental and behavioral disorders due to psychoactive substance use (F1), whereby the latter decreased over the years.

CONCLUSION

The implementation of prevention strategies, interdisciplinary approaches and psychological support in orthopaedics and trauma surgery is warranted.

TLC-Ag dressings: a prospective, multicentre study on 728 patients with wounds at risk of or with local infection

OBJECTIVE

This study aimed to evaluate the management of an unselected cohort of patients with wounds at risk of or with clinical signs of local infection, treated with two antimicrobial contact layers impregnated with silver (TLC-Ag healing matrix), under real-life conditions during the COVID-19 pandemic.

METHOD

A large, prospective, multicentre, observational study with two TLC-Ag dressings (UrgoTul Ag/Silver and UrgoTul Ag Lite Border, Laboratoires Urgo, France) was conducted in Germany between May 2020 and May 2021. The main outcomes included a description of the treated patients and their wound management, the changes in wound infection and wound healing outcomes over a maximum period of four weeks of treatment, as well as the overall clinical assessment of the performance, local tolerance and acceptability of dressings.

RESULTS

A total of 728 patients with wounds of various aetiologies and wound infection status were treated with the evaluated dressings in 39 centres for a mean duration of 26±19 days, with an intermediate visit conducted in 712 (97.8%) patients after a mean period of 12±9 days. At the initial visit, it was established that the majority of patients (60.4%) had a wound infection, while the remaining cohort presented first clinical signs of a local wound infection (25.1%) or were at risk of wound infection (13.2%) (unclear status in 1.2%). Throughout the study period, all the parameters of wound infection continuously decreased, resulting at the final visit in a reduction by 78.9% of the prevalence of local wound infections and by 72.0% of the clinical signs of wound infection, the most rapidly diminished clinical sign being wound deterioration. Concurrently, in terms of the healing process, 92.1% of the wounds healed or improved, 3.2% remained unchanged and 1.7% worsened (data missing for 3.0%), and an improvement of the periwound skin was reported in 65.7% of the patients. Overall, the two dressings were 'very well accepted' by the majority of patients, with no uncomfortable feeling at wearing and no pain at dressing removal, and were assessed by the physicians as 'very useful' in the majority of the cases with a 'very good' efficacy in terms of antimicrobial activity and promotion of the wound healing process. Similar results were reported regardless of the wound type treated or of the TLC-Ag dressing evaluated.

CONCLUSION

These results are consistent with previous clinical evidence on TLC-Ag dressings. They support the good efficacy, good tolerability and usefulness of these antimicrobial dressings in the management of patients with wounds at risk or with clinical signs of local infection, in association with appropriate standard of care.

Single stage versus two-stage orthoplastic management of bone infection

INTRODUCTION

Bone infection cases with major soft tissue loss have conventionally been treated with a staged orthoplastic approach, addressing the infection first followed by definitive management to achieve bony stability and soft tissue cover. In the last few decades, specialist centers have advocated for single stage bony stabilization with soft tissue coverage. We aimed to investigate the outcomes of patients that underwent a single stage versus a two-stage orthoplastic intervention.

METHODS

Using an existing 2009-2019 database from a single major trauma centre, we identified all adults with a diagnosis of fracture related infection (FRI) or osteomyelitis (OM). The primary outcome was resolution of infection. Secondary outcomes included time to bony union, amputation, failure of orthopaedic fixation, mortality, and return to theatre.

RESULTS

A total of 96 patients were included. 71 patients (74%) underwent a single stage procedure; out of which 61 were FRI. 25 patients (26%) underwent a two-stage procedure; out of which 24 were FRI. The average follow up for the single stage and two-stage cohorts was 32.1 and 30.3 months, respectively. Resolution of infection without the need for an amputation was achieved in 67 (94.4%) patients in the single stage cohort and in 23 (92%) patients in the two-stage cohort. When compared to the two-stage group, the single stage cohort had less recurrence of infection (9.9% versus 12%, p = 0.72), lower rates of amputation (8.5% versus 12%, p = 0.69), lower rates of failure of orthopaedic fixation (11.1% versus 13%, p = 0.82), but higher average time to bony union (15.25 months versus 12.35, p = 0.42). The differences were not statistically significant. A total of 37 patients (52.1%) had an unplanned return to theatre in the single stage compared to 12 (48%) in the two-stage cohort. In subgroup analysis of FRI cases, open fractures had a longer time to bony union when compared to closed fractures (19.7 versus 11.6 months, p = 0.01). No mortality was observed in both cohorts.

CONCLUSIONS

The single stage orthoplastic approach to bone infection is effective if planned carefully with clinical outcomes comparable to the two-stage approach. Further research should examine factors associated with unplanned return to theatre and any variation in treatment of bone infection across regions.

What Is the Most Effective Empirical Antibiotic Treatment for Early, Delayed, and Late Fracture-Related Infections?

Antibiotic treatment strategies for fracture-related infections (FRI) are often extrapolated from periprosthetic joint infections (PJI), although, in contrast to PJI, detailed analysis of pathogens and their antibiotic resistance is missing. Therefore, this study aimed to investigate antibiotic susceptibility profiles to identify effective empiric antibiotic treatment for early-, delayed-, and late-onset FRI. Patients treated for FRI from 2013 to 2020 were grouped into early (<2 weeks), delayed (3−10 weeks), and late (>10 weeks) onset of infection. Antibiotic susceptibility profiles were examined with respect to broadly used antibiotics and antibiotic combinations. In total, 117 patients (early n = 19, delayed n = 60, late n = 38) were enrolled. In early-onset FRI, 100.0% efficacy would be achieved by meropenem + vancomycin, gentamicin + vancomycin, co-amoxiclav + glycopeptide, ciprofloxacin + glycopeptide and piperacillin/tazobactam + glycopeptide. For patients with delayed FRI, the highest susceptibility was revealed for meropenem + vancomycin, gentamicin + vancomycin and ciprofloxacin + glycopeptide (96.7%). Meropenem + vancomycin was the most effective empiric antimicrobial in patients with late-onset of infection with 92.1% coverage. No subgroup differences in antibiotic sensitivity profiles were observed except for the combination ciprofloxacin + glycopeptide, which was significantly superior in early FRI (F = 3.304, p = 0.04). Across all subgroups meropenem + vancomycin was the most effective empiric treatment in 95.7% of patients with confirmed susceptibility. Meropenem + vancomycin, gentamicin + vancomycin, co-amoxiclav + glycopeptide are the best therapeutic options for FRI, regardless of the onset of infection. To avoid multidrug resistance, established antibiotic combinations such as co-amoxiclav with a glycopeptide seem to be reasonable as a systemic antibiotic therapy, while vancomycin + gentamicin could be implemented in local antibiotic therapy to reduce adverse events during treatment.

[Fracture-related infections after intramedullary nailing : Diagnostics and treatment]

Intramedullary nailing is the treatment of choice for a large number of fractures requiring surgery. In cases of fracture-related infections (FRI) the treatment of nail infections requires special attention due to the closed situation of the osteosynthesis material in the intramedullary canal. This article gives an overview of the general principles and diagnostic criteria for FRI after nail fixation and discusses the treatment recommendations based on three case examples. In cases of acute implant infections, an implant-retaining procedure is principally possible for both periprosthetic joint infections and FRI; however, after intramedullary nailing the nail should also be exchanged in cases of acute nail infections as a sufficient debridement of the nail is impossible due to its intramedullary location. In chronic FRI after intramedullary nailing a one-stage or two-stage procedure can be followed. In cases of adequate soft tissue coverage, good fracture reduction and an expected bone healing without critical bony substance defects, a one-stage procedure with nail exchange should be preferred. If a chronic infection with soft tissue and bone defects develops after intramedullary nailing, a two-stage procedure analogous to the treatment of osteomyelitis should be considered. In this case a multidisciplinary team approach with specialists in plastic surgery, microbiology and infectious diseases is necessary. The use of local antibiotics and antimicrobial-coated implants is deemed to be advantageous.

The Role of Negative-Pressure Wound Therapy in Patients with Fracture-Related Infection: A Systematic Review and Critical Appraisal

INTRODUCTION

Fracture-related infection (FRI) is a severe musculoskeletal complication in orthopedic trauma surgery, causing challenges in bony and soft tissue management. Currently, negative-pressure wound therapy (NPWT) is often used as temporary coverage for traumatic and surgical wounds, also in cases of FRI. However, controversy exists about the impact of NPWT on the outcome in FRI, specifically on infection recurrence. Therefore, this systematic review qualitatively assesses the literature on the role of NPWT in the management of FRI.

METHODS

A literature search of the PubMed, Embase, and Web of Science database was performed. Studies that reported on infection recurrence related to FRI management combined with NPWT were eligible for inclusion. Quality assessment was done using the PRISMA statement and the Newcastle-Ottawa Quality Assessment Scale.

RESULTS

After screening and quality assessment of 775 unique identified records, eight articles could be included for qualitative synthesis. All eight studies reported on infection recurrence, which ranged from 2.8% to 34.9%. Six studies described wound healing time, varying from two to seven weeks. Four studies took repeated microbial swabs during subsequent vacuum dressing changes. One study reported newly detected pathogens in 23% of the included patients, and three studies did not find new pathogens.

CONCLUSION

This review provides an assessment of current literature on the role of NPWT in the management of soft tissue defects in patients with FRI. Due to the lack of uniformity in included studies, conclusions should be drawn with caution. Currently, there is no clear scientific evidence to support the use of NPWT as definitive treatment in FRI. At this stage, we can only recommend early soft tissue coverage (within days) with a local or free flap. NPWT may be safe for a few days as temporarily soft tissue coverage until definitive soft tissue management could be performed. However, comparative studies between NPWT and early wound closure in FRI patients are needed.