Musculoskeletal Infection in Orthopaedic Trauma: Assessment of the 2018 International Consensus Meeting on Musculoskeletal Infection

Fracture-related infections (FRIs) are among the most common complications following fracture fixation, and they have a huge economic and functional impact on patients. Because consensus guidelines with respect to prevention, diagnosis, and treatment of this major complication are scarce, delegates from different countries gathered in Philadelphia in July 2018 as part of the Second International Consensus Meeting (ICM) on Musculoskeletal Infection. This paper summarizes the discussion and recommendations from that consensus meeting, using the Delphi technique, with a focus on FRIs. A standardized definition that was based on diagnostic criteria was endorsed, which will hopefully improve reporting and research on FRIs in the future. Furthermore, this paper provides a grade of evidence (strong, moderate, limited, or consensus) for strategies and practices that prevent and treat infection. The grade of evidence is based on the quality of evidence as utilized by the American Academy of Orthopaedic Surgeons. The guidelines presented herein focus not only on the appropriate use of antibiotics, but also on practices for the timing of fracture fixation, soft-tissue coverage, and bone defect and hardware management. We hope that this summary as well as the full document by the International Consensus Group are utilized by those who are charged with musculoskeletal care internationally to optimize their management strategies for the prevention and treatment of FRIs.

Diagnosing Fracture-Related Infection: Current Concepts and Recommendations

Fracture-related infection (FRI) is a severe complication after bone injury and can pose a serious diagnostic challenge. Overall, there is a limited amount of scientific evidence regarding diagnostic criteria for FRI. For this reason, the AO Foundation and the European Bone and Joint Infection Society proposed a consensus definition for FRI to standardize the diagnostic criteria and improve the quality of patient care and applicability of future studies regarding this condition. The aim of this article was to summarize the available evidence and provide recommendations for the diagnosis of FRI. For this purpose, the FRI consensus definition will be discussed together with a proposal for an update based on the available evidence relating to the diagnostic value of clinical parameters, serum inflammatory markers, imaging modalities, tissue and sonication fluid sampling, molecular biology techniques, and histopathological examination. Second, recommendations on microbiology specimen sampling and laboratory operating procedures relevant to FRI will be provided. LEVEL OF EVIDENCE:: Diagnostic Level V. See Instructions for Authors for a complete description of levels of evidence.

Recommendations for Systemic Antimicrobial Therapy in Fracture-Related Infection: A Consensus From an International Expert Group

Fracture-related infection (FRI) is a major complication in musculoskeletal trauma and one of the leading causes of morbidity. Standardization of general treatment strategies for FRI has been poor. One of the reasons is the heterogeneity in this patient population, including various anatomical locations, multiple fracture patterns, different degrees of soft-tissue injury, and different patient conditions. This variability makes treatment complex and hard to standardize. As these infections are biofilm-related, surgery remains the cornerstone of treatment, and this entails multiple key aspects (eg, fracture fixation, tissue sampling, debridement, and soft-tissue management). Another important aspect, which is sometimes less familiar to the orthopaedic trauma surgeon, is systemic antimicrobial therapy. The aim of this article is to summarize the available evidence and provide recommendations for systemic antimicrobial therapy with respect to FRI, based on the most recent literature combined with expert opinion. LEVEL OF EVIDENCE:: Therapeutic Level V. See Instructions for Authors for a complete description of levels of evidence.

Bacteriophage Application for Difficult-to-treat Musculoskeletal Infections: Development of a Standardized Multidisciplinary Treatment Protocol

Bacteriophage therapy has recently attracted increased interest, particularly in difficult-to-treat infections. Although it is not a novel concept, standardized treatment guidelines are currently lacking. We present the first steps towards the establishment of a "multidisciplinary phage task force" (MPTF) and a standardized treatment pathway, based on our experience of four patients with severe musculoskeletal infections. After review of their medical history and current clinical status, a multidisciplinary team found four patients with musculoskeletal infections eligible for bacteriophage therapy within the scope of Article 37 of the Declaration of Helsinki. Treatment protocols were set up in collaboration with phage scientists and specialists. Based on the isolated pathogens, phage cocktails were selected and applied intraoperatively. A draining system allowed postoperative administration for a maximum of 10 days, 3 times per day. All patients received concomitant antibiotics and their clinical status was followed daily during phage therapy. No severe side-effects related to the phage application protocol were noted. After a single course of phage therapy with concomitant antibiotics, no recurrence of infection with the causative strains occurred, with follow-up periods ranging from 8 to 16 months. This study presents the successful outcome of bacteriophage therapy using a standardized treatment pathway for patients with severe musculoskeletal infection. A multidisciplinary team approach in the form of an MPTF is paramount in this process.

Segmental Bone Loss of the Clavicle due to Fracture-Related Infection: A Multidisciplinary Challenge

As the surgical treatment of clavicular fractures is increasingly utilized in orthopedics, the number of related complications rises as well. We present a case of segmental bone loss of the clavicle due to fracture-related infection. Treatment was based on a multidisciplinary team approach, which was important for a successful outcome.

Preclinical in vivo models of fracture-related infection: a systematic review and critical appraisal

A fracture-related infection (FRI) is an important complication that can lead to an increase in morbidity, mortality and economic costs. Preclinical in vivo models are critical in the evaluation of novel prevention and treatment strategies, yet it is important that these studies recapitulate the features of an FRI that make it such a clinical challenge. The aim of this systematic review was to survey the available preclinical models of FRIs and assess which of the key FRI-specific parameters are incorporated in these models. A comprehensive search was performed on July 1st 2017 in PubMed, Embase and Web of Science. Overall, 75 preclinical studies were identified, 97.3 % (n = 73) of which use Staphylococcus aureus as the causative microorganism. The most common mode for creation of bone instability is an osteotomy (n = 30; 40 %), followed by the creation of a defect (n = 26; 34.7 %). An actual fracture is created in only 19 studies (25.3 %). 12 (16 %) of the models include a time gap between bacterial inoculation and fixation to mimic the time-to-treatment in clinical open fracture scenarios. This systematic review reveals that animal models used in translational research on prevention and treatment of FRIs rarely incorporate all key clinical features in one model and that there is an over-representation of S. aureus in comparison to actual clinical epidemiology. To improve the relevance of these studies, existing preclinical models should be adapted or new models developed that better recapitulate the clinical condition of FRI.

The implementation of a clinical pathway enhancing early surgery for geriatric hip fractures: how to maintain a success story?

BACKGROUND

Timing of surgery in geriatric hip fracture treatment remains controversial. Early surgery is acknowledged as a quality indicator and NICE guidelines recommend surgery within 0-48 h from admission. In 2014 we implemented the indicator of early surgery in our institution, enhancing operative treatment within the next calendar day. We aimed to evaluate the implementation, define the room for improvement and provide strategies to maintain the quality indicator.

METHODS

Clinical outcome of 744 patients (January 2011-December 2013) before early surgery was implemented, compared to 817 patients (June 2014-May 2017) after implementation of early surgery with a follow-up of 6 months. Data-analysis was done by Pearson's Chi-square test and Mann-Whitney U test.

RESULTS

Early surgery was achieved in 47.6% and 85.7% in the preimplementation and postimplementation group, respectively (P < 0.001). Both 30 days and 6 months mortality were similar (6.0% vs. 5.4%, P = 0.573 and 18.7% vs. 16.9%, P = 0.355, preimplementation vs. postimplementation, respectively). Early surgery resulted in a significantly shorter total length-of-stay (14 vs. 12 days, P < 0.001, preimplementation vs. postimplementation, respectively). Early surgery did not reduce the readmission rate.

CONCLUSIONS

The indicator of early surgery has been successfully implemented. Early surgery resulted in a significantly shorter LOS. No significant reduction in 30 days and 6 months mortality, and 90 days readmission was observed. To maintain early surgery, continuous engagement and monitoring is required by all shareholders involved and if necessary, adjustment of the clinical route is appropriate.

Is open acute Achilles tendon rupture repair still justified? A single center experience and critical appraisal of the literature

INTRODUCTION

Acute Achilles tendon ruptures are injuries with multiple treatment strategies with possibly far reaching consequences. Open repair is associated with a high complication rate, whereas percutaneous techniques are associated with higher re-rupture rates. The goal of this study was to evaluate the clinical outcome and economic burden of open surgical repair and define a medically and economically sound treatment protocol for acute Achilles tendon ruptures.

METHODS

Between June 2012 and December 2016 one hundred and five patients with an acute Achilles tendon rupture, treated in an open surgical manner, were studied retrospectively. All demographic, clinical and hospital-related costs were retrieved from the electronic patient database. ATRS questionnaires were sent to assess the functional outcome. A response rate of 70.5% was achieved.

RESULTS

We recorded a complication rate of 40%, respectively sural nerve hypoesthesia (14.3%), delayed wound healing (28.6%), infection (20.9%) and re-rupture (4.8%). Surgical resident, as primary operating surgeon was associated with a higher complication rate (p = 0.042). Overall, a median functional ATRS score of 17 (IQR 6.5-39.5) was recorded. Infection was associated with significantly higher total healthcare costs per patient as compared to re-rupture (€17,435 vs. €4,537, p = 0.013). The total cost for surgical debridement (n = 6) was approximately 5-times higher than for re-rupture (n = 5), €108,382 vs. €22,272. The median ATRS score for surgical debridement after infection and re-rupture did not differ significantly from the overall ATRS score, respectively 32 (IQR 21-63) and 28 (IQR 15-28). Nevertheless, a difference of 10 points is considered clinically relevant.

CONCLUSION

The overall functional outcome of open repair of Achilles tendon ruptures is rather good, however associated with a high complication rate, mainly due to wound problems and infection. Although several risk factors were identified, only the operating surgeon is modifiable. Considering the high total costs for surgical debridement in the context of infection compared to re-rupture surgery, despite equal functional outcome,we decided to change clinical practice to reduce the complication rate and healthcare costs. The outcome and precise costs for percutaneous repair will be addressed.

Accuracy of Tissue and Sonication Fluid Sampling for the Diagnosis of Fracture-Related Infection: A Systematic Review and Critical Appraisal

Introduction: Intraoperatively obtained peri-implant tissue cultures remain the standard for diagnosis of fracture-related infection (FRI), although culture-negative cases may complicate treatment decisions. This paper reviews the evidence on sonication fluid and tissue sampling for the diagnosis of FRI.

Methods: A comprehensive search in Pubmed, Embase and Web-of-Science was carried out on April 5, 2018, to identify diagnostic validation studies regarding sonication fluid and tissue sampling for FRI.

Results: Out of 2624 studies, nine fulfilled the predefined inclusion criteria. Five studies focused on sonication fluid culture, two on PCR and two on histopathology. One additional histopathology study was found after screening of reference lists. There is limited evidence that sonication fluid culture may be a useful adjunct to conventional tissue culture, but no strong evidence that it is superior or can replace tissue culture. Regarding molecular techniques and histopathology the evidence is even less clear. Overall, studies had variable 'gold standard' criteria for comparison and poorly reported culture methods.

Conclusions: Scientific evidence on sonication fluid and tissue sampling, including culture, molecular techniques and histopathology for the diagnosis of FRI is scarce. It is imperative that laboratory protocols become standardized and uniform diagnostic criteria, as recently published in a consensus definition, be implemented.

The effect of local antibiotic prophylaxis when treating open limb fractures: A systematic review and meta-analysis

Objectives

As well as debridement and irrigation, soft-tissue coverage, and osseous stabilization, systemic antibiotic prophylaxis is considered the benchmark in the management of open fractures and considerably reduces the risk of subsequent fracture-related infections (FRI). The direct application of antibiotics in the surgical field (local antibiotics) has been used for decades as additional prophylaxis in open fractures, although definitive evidence confirming a beneficial effect is scarce. The purpose of the present study was to review the clinical evidence regarding the effect of prophylactic application of local antibiotics in open limb fractures.

Methods

A comprehensive literature search was performed in PubMed, Web of Science, and Embase. Cohort studies investigating the effect of additional local antibiotic prophylaxis compared with systemic prophylaxis alone in the management of open fractures were included and the data were pooled in a meta-analysis.

Results

In total, eight studies which included 2738 patients were eligible for quantitative synthesis. The effect of antibiotic-loaded poly(methyl methacrylate) beads was investigated by six of these studies, and two studies evaluated the effect of local antibiotics applied without a carrier. Meta-analysis showed a significantly lower infection rate when local antibiotics were applied (4.6%; 91/1986) than in the control group receiving standard systemic prophylaxis alone (16.5%; 124/752) (p < 0.001) (odds ratio 0.30; 95% confidence interval 0.22 to 0.40).

Conclusion

This meta-analysis suggests a risk reduction in FRI of 11.9% if additional local antibiotics are given prophylactically for open limb fractures. However, due to limited quality, heterogeneity, and considerable risk of bias, the pooling of data from primary studies has to be interpreted with caution.

Cite this article: M. Morgenstern, A. Vallejo, M. A. McNally, T. F. Moriarty, J. Y. Ferguson, S. Nijs, WJ. Metsemakers. Bone Joint Res 2018;7:447–456. The effect of local antibiotic prophylaxis when treating open limb fractures: A systematic review and meta-analysis. DOI: 10.1302/2046-3758.77.BJR-2018-0043.R1

Diagnostic challenges and future perspectives in fracture-related infection

Fracture-related infection (FRI) is one of the most challenging complications in orthopaedic trauma surgery. It has severe consequences for patients and an important socio-economic impact. FRI has distinct properties and needs to be addressed interdisciplinary. Since criteria for the diagnosis of FRI are not standardized, an expert panel recently proposed a definition for FRI. In this review the current diagnostic modalities and an interdisciplinary diagnostic algorithm based on this recently published definition, are presented and future diagnostic techniques discussed. Since to date, there is no single universal diagnostic test available that gives the clinician the definitive diagnosis of FRI, it is mandatory to follow a standardized diagnostic algorithm to correctly diagnose FRI.

Are the current guidelines for surgical delay in hip fractures too rigid? A single center assessment of mortality and economics

PURPOSE

Controversy remains around acceptable surgical delay of acute hip fractures with current guidelines ranging from 24 to 48 h. Increasing healthcare costs force us to consider the economic burden as well. We aimed to evaluate the adjusted effect of surgical delay for hip fracture surgery on early mortality, healthcare costs and readmission rate. We hypothesized that shorter delays resulted in lower early mortality and costs.

METHODS

In this retrospective cohort study 2573 consecutive patients aged ≥50 years were included, who underwent surgery for acute hip fractures between 2009 and 2017. Main endpoints were thirty- and ninety-day mortality, total cost, and readmission rate. Multivariable regression included sex, age and ASA score as covariates.

RESULTS

Thirty-day mortality was 5% (n = 133), ninety-day mortality 12% (n = 304). Average total cost was €11960, dominated by hospitalization (59%) and honoraria (23%). Per 24 h delay, the adjusted odds ratio was 1.07 (95% CI 0.98-1.18) for thirty-day mortality, 1.12 (95% CI 1.04-1.19) for ninety-day mortality, and 0.99 (95% CI = 0.88-1.12) for readmission. Per 24 h delay, costs increased with 7% (95% CI 6-8%). For mortality, delay was a weaker predictor than sex, age, and ASA score. For costs, delay was the strongest predictor. We did not find clear cut-points for surgical delay after which mortality or costs increased abruptly.

CONCLUSIONS

Despite only modest associations with mortality, we observed a steady increase in healthcare costs when delaying surgery. Hence, a more pragmatic approach with surgery as soon as medically and organizationally possible seems justifiable over rigorous implementation of the current guidelines.

Infection after fracture fixation: Current surgical and microbiological concepts

One of the most challenging complications in trauma surgery is infection after fracture fixation (IAFF). IAFF may result in permanent functional loss or even amputation of the affected limb in patients who may otherwise be expected to achieve complete, uneventful healing. Over the past decades, the problem of implant related bone infections has garnered increasing attention both in the clinical as well as preclinical arenas; however this has primarily been focused upon prosthetic joint infection (PJI), rather than on IAFF. Although IAFF shares many similarities with PJI, there are numerous critical differences in many facets including prevention, diagnosis and treatment. Admittedly, extrapolating data from PJI research to IAFF has been of value to the trauma surgeon, but we should also be aware of the unique challenges posed by IAFF that may not be accounted for in the PJI literature. This review summarizes the clinical approaches towards the diagnosis and treatment of IAFF with an emphasis on the unique aspects of fracture care that distinguish IAFF from PJI. Finally, recent developments in anti-infective technologies that may be particularly suitable or applicable for trauma patients in the future will be briefly discussed.

Definition of infection after fracture fixation: A systematic review of randomized controlled trials to evaluate current practice

INTRODUCTION

One of the most challenging musculoskeletal complications in modern trauma surgery is infection after fracture fixation (IAFF). Although infections are clinically obvious in many cases, a clear definition of the term IAFF is crucial, not only for the evaluation of published research data but also for the establishment of uniform treatment concepts. The aim of this systematic review was to identify the definitions used in the scientific literature to describe infectious complications after internal fixation of fractures. The hypothesis of this study was that the majority of fracture-related literature do not define IAFF.

MATERIAL AND METHODS

A comprehensive search was performed in Embase, Cochrane, Google Scholar, Medline (OvidSP), PubMed publisher and Web-of-Science for randomized controlled trials (RCTs) on fracture fixation. Data were collected on the definition of infectious complications after fracture fixation used in each study. Study selection was accomplished through two phases. During the first phase, titles and abstracts were reviewed for relevance, and the full texts of relevant articles were obtained. During the second phase, full-text articles were reviewed. All definitions were literally extracted and collected in a database. Then, a classification was designed to rate the quality of the description of IAFF.

RESULTS

A total of 100 RCT's were identified in the search. Of 100 studies, only two (2%) cited a validated definition to describe IAFF. In 28 (28%) RCTs, the authors used a self-designed definition. In the other 70 RCTs, (70%) there was no description of a definition in the Methods section, although all of the articles described infections as an outcome parameter in the Results section.

CONCLUSION

This systematic review shows that IAFF is not defined in a large majority of the fracture-related literature. To our knowledge, this is the first study conducted with the objective to explore this important issue. The lack of a consensus definition remains a problem in current orthopedic trauma research and treatment and this void should be addressed in the near future.

Fracture-related infection: A consensus on definition from an international expert group

Fracture-related infection (FRI) is a common and serious complication in trauma surgery. Accurately estimating the impact of this complication has been hampered by the lack of a clear definition. The absence of a working definition of FRI renders existing studies difficult to evaluate or compare. In order to address this issue, an expert group comprised of a number of scientific and medical organizations has been convened, with the support of the AO Foundation, in order to develop a consensus definition. The process that led to this proposed definition started with a systematic literature review, which revealed that the majority of randomized controlled trials in fracture care do not use a standardized definition of FRI. In response to this conclusion, an international survey on the need for and key components of a definition of FRI was distributed amongst all registered AOTrauma users. Approximately 90% of the more than 2000 surgeons who responded suggested that a definition of FRI is required. As a final step, a consensus meeting was held with an expert panel. The outcome of this process led to a consensus definition of FRI. Two levels of certainty around diagnostic features were defined. Criteria could be confirmatory (infection definitely present) or suggestive. Four confirmatory criteria were defined: Fistula, sinus or wound breakdown; Purulent drainage from the wound or presence of pus during surgery; Phenotypically indistinguishable pathogens identified by culture from at least two separate deep tissue/implant specimens; Presence of microorganisms in deep tissue taken during an operative intervention, as confirmed by histopathological examination. Furthermore, a list of suggestive criteria was defined. These require further investigations in order to look for confirmatory criteria. In the current paper, an overview is provided of the proposed definition and a rationale for each component and decision. The intention of establishing this definition of FRI was to offer clinicians the opportunity to standardize clinical reports and improve the quality of published literature. It is important to note that the proposed definition was not designed to guide treatment of FRI and should be validated by prospective data collection in the future.

International survey among orthopaedic trauma surgeons: Lack of a definition of fracture-related infection

INTRODUCTION

Fracture-related infection (FRI) is one of the most challenging musculoskeletal complications in orthopaedic-trauma surgery. Although the orthopaedic community has developed and adopted a consensus definition of prosthetic joint infections (PJI), it still remains unclear how the trauma surgery community defines FRI in daily clinical practice or in performing clinical research studies. The central aim of this study was to survey the opinions of a global network of trauma surgeons on the definitions and criteria they routinely use, and their opinion on the need for a unified definition of FRI. The secondary aims were to survey their opinion on the utility of currently used definitions that may be at least partially applicable for FRI, and finally their opinion on the important clinical parameters that should be considered as diagnostic criteria for FRI.

METHODS

An 11-item questionnaire was developed to cover the above-mentioned aims. The questionnaire was administered by SurveyMonkey and was sent via blast email to all registered users of AO Trauma (Davos, Switzerland).

RESULTS

Out of the 26'563 recipients who opened the email, 2'327 (8.8%) completed the questionnaire. Nearly 90% of respondents agreed that a consensus-derived definition for FRI is required and 66% of the surgeons also agreed that PJI and FRI are not equal with respect to diagnosis, treatment and outcome. Furthermore, "positive cultures from microbiology testing", "elevation of CRP", "purulent drainage" and "local clinical signs of infection" were voted the most important diagnostic parameters for FRI.

CONCLUSION

This international survey infers the need for a consensus definition of FRI and provides insight into the clinical parameters seen by an international community of trauma surgeons as being critical for defining FRI.

Economics of open tibial fractures: the pivotal role of length-of-stay and infection

In order to define strategies to curb the continuing increase in healthcare costs, we describe the cost breakdown of open tibial fractures. Twenty-seven clinical and process variables were recorded retrospectively, and five main hospital related cost categories were defined. Three multivariate linear models were fitted to the data. Total healthcare costs of open tibial fractures were almost twice as high compared to closed fractures and mainly existed of hospitalization costs. Length-of-stay (LOS) was found to be the most important variable driving the healthcare costs of open tibial fractures. Deep infection lead to a 6-fold increase of LOS and 5-fold increase in total healthcare costs of open tibial fractures. Therefore, appropriate international consensus guidelines are required to improve not only the patient outcome (infection prevention) but also reduce overall healthcare cost by focusing on reducing the LOS.

Reamer-Irrigator-Aspirator bone graft harvesting for treatment of segmental bone loss: analysis of defect volume as independent risk factor for failure

INTRODUCTION

The management of segmental bone loss poses a significant clinical challenge. The purpose of this study was to conduct a retrospective evaluation of our experience in treating segmental bone loss, using Reamer-Irrigator-Aspirator (RIA)-harvested autologous bone graft.

MATERIALS AND METHODS

Between June 2008 and March 2015, 81 patients were treated with the RIA technique for multiple purposes. Inclusion criteria for this study were skeletal mature patients with segmental bone loss, due to acute trauma or non-union, who were treated with RIA-harvested bone graft. Exclusion criteria were skeletal immaturity, pathological fractures and indications for the RIA system other than bone graft harvesting. The primary outcome parameter was clinical and radiographical bone healing.

RESULTS

During the study period, 72 patients met the inclusion criteria. In total, 39 patients (54.2%) were classified as having clinical and radiographical bone healing. Although univariate analysis could not reveal any significant influence of specific risk factors to predict the outcome, there was a trend towards statistical significance for defect volume. Further analysis indeed revealed that smaller defect volumes (< 8 cm³) had a lower risk of non-union.

CONCLUSIONS

In approximately half of our study population, the use of the RIA technique for autologous bone graft harvesting in cases of segmental bone loss resulted in a successful outcome with bone healing. Defect size seems to be a critical issue regarding the outcome. Although our results are less promising than previously published, the RIA technique has its place in the treatment algorithm of segmental bone defects.

Infection after fracture fixation of the tibia: Analysis of healthcare utilization and related costs

INTRODUCTION

One of the most challenging complications in musculoskeletal trauma surgery is the development of infection after fracture fixation (IAFF). It can delay healing, lead to permanent functional loss, or even amputation of the affected limb. The main goal of this study was to investigate the total healthcare costs and length-of-stay (LOS) related to the surgical treatment of tibia fractures and furthermore identify the subset of clinical variables driving these costs within the Belgian healthcare system. The hypothesis was that deep infection would be the most important driver for total healthcare costs.

PATIENTS AND METHODS

Overall, 358 patients treated operatively for AO/OTA type 41, 42, and 43 tibia fractures between January 1, 2009 and January 1, 2014 were included in this study. A total of 26 clinical and process variables were defined. Calculated costs were limited to hospital care covered by the Belgian healthcare financing system. The five main cost categories studied were: honoraria, materials, hospitalization, day care admission, and pharmaceuticals.

RESULTS

Multivariate analysis showed that deep infection was the most significant characteristic driving total healthcare costs and LOS related to the surgical treatment of tibia fractures. Furthermore, this complication resulted in the highest overall increase in total healthcare costs and LOS. Treatment costs were approximately 6.5-times higher compared to uninfected patients.

CONCLUSION

This study shows the enormous hospital-related healthcare costs associated with IAFF of the tibia. Treatment costs for patients with deep infection are higher than previously mentioned in the literature. Therefore, future research should focus more on prevention rather than treatment strategies, not only to reduce patient morbidity but also to reduce the socio-economic impact.

Injectable gentamicin-loaded thermo-responsive hyaluronic acid derivative prevents infection in a rabbit model

Despite the use of systemic antibiotic prophylaxis, the surgical fixation of open fractures with osteosynthesis implants is associated with high infection rates. Antibiotic-loaded biomaterials (ALBs) are increasingly used in implant surgeries across medical specialties to deliver high concentrations of antibiotics to the surgical site and reduce the risk of implant-associated infection. ALBs which are either less or not restricted in terms of spatial distribution and which may be applied throughout complex wounds could offer improved protection against infection in open fracture care. A thermo-responsive hyaluronic acid derivative (hyaluronic acid-poly(N-isopropylacrylamide) (HApN)) was prepared by a direct amidation reaction between the tetrabutyl ammonium (TBA) salt of hyaluronic acid and amine-terminated poly(N-isopropylacrylamide) (pN). The degree of grafting, and gelation properties of this gel were characterized, and the composition was loaded with gentamicin. The rheological- and release properties of this gentamicin-loaded HApN composition were tested in vitro and its efficacy in preventing infection was tested in a rabbit model of osteosynthesis contaminated with Staphylococcus aureus. The gentamicin-loaded HApN composition was able to prevent bacterial colonization of the implant site as shown by quantitative bacteriology. This finding was supported by histopathological evaluation of the humeri samples where no bacteria were found in the stained sections. In conclusion, this gentamicin-loaded HApN hydrogel effectively prevents infection in a complex wound, simulating a contaminated fracture treated with plating osteosynthesis.

STATEMENT OF SIGNIFICANCE

Fracture fixation after trauma is associated with high infection rates. Antibiotic loaded biomaterials (ALBs) can provide high local concentrations without systemic side effects. However, the currently available ALBs have limited accessibility to contaminated tissues in open fractures because of predetermined shape. Thus, a novel thermo-responsive hyaluronan based hydrogel with control over gelation temperature is reported. The efficacy of this gentamicin loaded hyaluronan derivative is demonstrated in an in vivo fracture model in the presence of fracture fixation hardware. The bacterial burden is cleared in all of the inoculated rabbits in the presence of the ALB. Thus, the proposed injectable thermo-responsive hyaluronan presents an effective ALB for the prevention of infection.

Orthopaedic device-related infection: current and future interventions for improved prevention and treatment

Orthopaedic and trauma device-related infection (ODRI) remains one of the major complications in modern trauma and orthopaedic surgery.Despite best practice in medical and surgical management, neither prophylaxis nor treatment of ODRI is effective in all cases, leading to infections that negatively impact clinical outcome and significantly increase healthcare expenditure.The following review summarises the microbiological profile of modern ODRI, the impact antibiotic resistance has on treatment outcomes, and some of the principles and weaknesses of the current systemic and local antibiotic delivery strategies.The emerging novel strategies aimed at preventing or treating ODRI will be reviewed. Particular attention will be paid to the potential for clinical impact in the coming decades, when such interventions are likely to be critically important.The review focuses on this problem from an interdisciplinary perspective, including basic science innovations and best practice in infectious disease. Cite this article: Moriarty TF, Kuehl R, Coenye T, et al. Orthopaedic device related infection: current and future interventions for improved prevention and treatment. EFORT Open Rev 2016;1:89-99. DOI: 10.1302/2058-5241.1.000037.

The use of gentamicin-coated nails in complex open tibia fracture and revision cases: A retrospective analysis of a single centre case series and review of the literature

INTRODUCTION

Despite modern advances in fracture care, deep (implant-related) infection remains a problem in the treatment of tibia fractures. There is some evidence that antibiotic-coated implants are beneficial in the prevention of this sometimes devastating complication. In the following study we describe our results using a gentamicin-coated intramedullary tibia nail (Expert Tibia Nail (ETN) PROtect™) for the surgical treatment of complex open tibia fracture and revision cases.

MATERIALS AND METHODS

We describe the outcome of patients treated between January 2012 and September 2013, using a gentamicin-coated intramedullary tibia nail. Treatment indications included acute, Gustilo grade II-III, open tibia fractures or closed tibia fractures with long-term external fixation prior to intramedullary nailing and complex tibia fracture revision cases with a mean of three prior surgical interventions. Outcome parameters in this study were deep infection and nonunion.

RESULTS

In total, 16 consecutive patients with 16 tibia fractures were treated with a gentamicin-coated intramedullary nail. The overall patient population was subdivided into two groups. The first group consisted of 11 patients (68.8%) with acute fractures who were treated with a gentamicin-coated intramedullary nail. The second group consisted of 5 complex revision cases (31.2%). In our patient population no deep infections could be noted after the treatment with a gentamicin-coated tibia nail. Nonunion was diagnosed in 4 patients (25.0%), 1 of these was a revision case.

CONCLUSIONS

Musculoskeletal complications place a cost burden on total healthcare expenditure. Better understanding of the epidemiology and pathogenesis is essential because this can lead to prevention rather than treatment strategies. The purpose of the study was to evaluate a gentamicin-coated tibia nail in the prevention of deep (implant-related) infection. In our patient population no deep infections occurred after placement of the gentamicin-coated nail. Following this study and literature data, antibiotic-coated implants seem a potential option for prevention of deep infection in trauma patients. In the future this statement needs to be confirmed by large randomised clinical trials.

A doxycycline-loaded polymer-lipid encapsulation matrix coating for the prevention of implant-related osteomyelitis due to doxycycline-resistant methicillin-resistant Staphylococcus aureus

Implant-associated bone infections caused by antibiotic-resistant pathogens pose significant clinical challenges to treating physicians. Prophylactic strategies that act against resistant organisms, such as methicillin-resistant Staphylococcus aureus (MRSA), are urgently required. In the present study, we investigated the efficacy of a biodegradable Polymer-Lipid Encapsulation MatriX (PLEX) loaded with the antibiotic doxycycline as a local prophylactic strategy against implant-associated osteomyelitis. Activity was tested against both a doxycycline-susceptible (doxy(S)) methicillin-susceptible S. aureus (MSSA) as well as a doxycycline-resistant (doxy(R)) methicillin-resistant S. aureus (MRSA). In vitro elution studies revealed that 25% of the doxycycline was released from the PLEX-coated implants within the first day, followed by a 3% release per day up to day 28. The released doxycycline was highly effective against doxy(S) MSSA for at least 14days in vitro. A bolus injection of doxycycline mimicking a one day release from the PLEX-coating reduced, but did not eliminate, mouse subcutaneous implant-associated infection (doxy(S) MSSA). In a rabbit intramedullary nail-related infection model, all rabbits receiving a PLEX-doxycycline-coated nail were culture negative in the doxy(S) MSSA-group and the surrounding bone displayed a normal physiological appearance in both histological sections and radiographs. In the doxy(R) MRSA inoculated rabbits, a statistically significant reduction in the number of culture-positive samples was observed for the PLEX-doxycycline-coated group when compared to the animals that had received an uncoated nail, although the reduction in bacterial burden did not reach statistical significance. In conclusion, the PLEX-doxycycline coating on titanium alloy implants provided complete protection against implant-associated MSSA osteomyelitis, and resulted in a significant reduction in the number of culture positive samples when challenged with a doxycycline-resistant MRSA.

Pancreas transplantation: towards minimization of technical graft loss

The objective of the study is to determine whether evolution in surgical techniques results in minimization of technical graft loss after simultaneous pancreas-kidney transplantation (SPKTx). Eighty consecutive patients with insulin-dependent diabetes mellitus and end-stage nephropathy, and who received SPKTx, were studied. Patient, pancreas and kidney survival at 5 years were 89, 84 and 84% respectively. The porto-systemic venous anastomosis laterally to the arterial vessels resulted in exclusion of technical graft loss due to venous thrombosis. The switch from exocrine bladder drainage to enteric drainage lowered significantly the posttransplant surgical morbidity. This series indicates that excellent short- and long-term survival can be obtained after SPKTx and this with a low perioperative surgical morbidity.