Management of bone infections in adults: the surgeon's and microbiologist's perspectives

Emerging 2D Nanomaterials-Integrated Hydrogels: Advancements in Designing Theragenerative Materials for Bone Regeneration and Disease Therapy

This review highlights recent advancements in the synthesis, processing, properties, and applications of 2D-material integrated hydrogels, with a focus on their performance in bone-related applications. Various synthesis methods and types of 2D nanomaterials, including graphene, graphene oxide, transition metal dichalcogenides, black phosphorus, and MXene are discussed, along with strategies for their incorporation into hydrogel matrices. These composite hydrogels exhibit tunable mechanical properties, high surface area, strong near-infrared (NIR) photon absorption and controlled release capabilities, making them suitable for a range of regeneration and therapeutic applications. In cancer therapy, 2D-material-based hydrogels show promise for photothermal and photodynamic therapies, and drug delivery (chemotherapy). The photothermal properties of these materials enable selective tumor ablation upon NIR irradiation, while their high drug-loading capacity facilitates targeted and controlled release of chemotherapeutic agents. Additionally, 2D-materials -infused hydrogels exhibit potent antibacterial activity, making them effective against multidrug-resistant infections and disruption of biofilm generated on implant surface. Moreover, their synergistic therapy approach combines multiple treatment modalities such as photothermal, chemo, and immunotherapy to enhance therapeutic outcomes. In bio-imaging, these materials serve as versatile contrast agents and imaging probes, enabling their real-time monitoring during tumor imaging. Furthermore, in bone regeneration, most 2D-materials incorporated hydrogels promote osteogenesis and tissue regeneration, offering potential solutions for bone defects repair. Overall, the integration of 2D materials into hydrogels presents a promising platform for developing multifunctional theragenerative biomaterials.

Latent Chronic Osteomyelitis Presenting Decades After Initial Trauma: A Case Report and Literature Review

Osteomyelitis is an inflammatory bone process secondary to infection, and often presents as a chronic, recurrent illness, posing diagnostic and treatment challenges. It is frequently the result of previous inadequate treatment or undiagnosed acute infection. Clinical suspicion, thorough evaluation, laboratory studies, and advanced imaging modalities such as magnetic resonance imaging (MRI) and computed tomography (CT) play crucial roles in diagnosis. Treatment typically entails a combination of antibiotics and surgical debridement to eliminate infection and facilitate bone healing. In this report, we present a rare case involving a 64-year-old male who presented with new-onset pain in the right femur decades after experiencing a complicated femur fracture and forearm crush injury. Imaging studies revealed evidence of chronic osteomyelitis, leading to a diagnosis of latent infection. The patient underwent a comprehensive evaluation, including clinical examination, imaging studies, laboratory tests, and bone biopsy, confirming the diagnosis. This case of latent osteomyelitis highlights the clinical presentation, diagnostic modalities, and treatment strategies employed in managing this challenging condition.

Muscle versus Fascia Free Tissue Transfer for Treatment of Chronic Osteomyelitis in the Comorbid Population

BACKGROUND

 In patients with chronic lower extremity (LE) wounds, chronic osteomyelitis confers additional complexity to achieving adequate treatment. Previous reviews demonstrate increased rates of osteomyelitis recurrence in patients who receive muscle flaps compared with fasciocutaneous flaps for LE limb salvage; however, these studies were not limited to atraumatic populations who receive exclusively free flaps. Thus, this study compared rates of recurrence in chronic osteomyelitis patients undergoing LE reconstruction with fasciocutaneous versus muscle free flaps.

METHODS

 Patients undergoing free tissue transfer (FTT) between July 2011 and July 2021 were retrospectively reviewed. Patients were stratified into fasciocutaneous and muscle free flap groups. Primary outcomes included osteomyelitis recurrence, flap complications, limb salvage, and ambulatory status.

RESULTS

 Forty-eight patients with pathologic diagnosis of chronic osteomyelitis of the wound bed were identified, of which 58.3% received fasciocutaneous (n = 28) and 41.7% received muscle flaps (n = 20). The most common comorbidities included diabetes mellitus (n = 29, 60.4%), peripheral neuropathy (n = 27, 56.3%) and peripheral vascular disease (n = 24, 50.0%). Methicillin-resistant or methicillin -sensitive Staphylococcus aureus were the most common pathogen in 18.7% (n = 9) of procedures. The majority of patients underwent a median of three debridements followed by negative pressure wound therapy prior to receiving FTT. At a median follow-up of 16.6 months, the limb salvage and ambulatory rates were 79.2 (n = 38) and 83.3% (n = 40), respectively. The overall rate of microsurgical flap success was 93.8% (n = 45). Osteomyelitis recurred in 25% of patients (n = 12) at a median duration of 4.0 months. There were no significant differences in rates of osteomyelitis recurrence, flap complications, limb salvage, ambulation, and mortality. On multivariate analysis, flap composition remained a nonsignificant predictor of osteomyelitis recurrence (odds ratio: 0.975, p = 0.973).

CONCLUSION

 This study demonstrates that flap composition may not influence recurrence of osteomyelitis following free flap reconstruction of chronic LE wounds, suggesting that optimal flap selection should be based on wound characteristics and patient goals.

Long-Term Outcomes Following Single-Stage Reamed Intramedullary Exchange Nailing in Apparently Aseptic Femoral Shaft Nonunion with Unsuspected Proof of Bacteria

Background: The aim of this study was to evaluate detection rates and risk factors for unsuspected proof of bacteria, as well as clinical and radiologic outcomes following femoral shaft nonunion without clinical signs of infection treated by a single-stage surgical revision procedure including reamed intramedullary exchange nailing. Methods: A retrospective cohort study was performed in a European level I trauma center between January 2015 and December 2022. Fifty-eight patients were included who underwent reamed intramedullary exchange nailing as a single-step procedure for surgical revision of posttraumatic diaphyseal femoral nonunion without any indications of infection in medical history and without clinical signs of local infection. Clinical details of the patients were analyzed and functional and radiologic long-term outcomes were determined. Results: In all patients, with and without proof of bacteria osseous, healing could be observed. The physical component summary of the SF-12 demonstrated significantly better results at least one year after the final surgical revision in case of a negative bacterial culture during exchange nailing. Conclusions: Clinical long-term outcomes demonstrated a trend towards better results following femoral shaft nonunion revision if there was no evidence for the presence of low-grade infected nonunion. In this case, a single-stage surgical procedure may be recommended.

Repair of Infected Bone Defects with Hydrogel Materials

Infected bone defects represent a common clinical condition involving bone tissue, often necessitating surgical intervention and antibiotic therapy. However, conventional treatment methods face obstacles such as antibiotic resistance and susceptibility to postoperative infections. Hydrogels show great potential for application in the field of tissue engineering due to their advantageous biocompatibility, unique mechanical properties, exceptional processability, and degradability. Recent interest has surged in employing hydrogels as a novel therapeutic intervention for infected bone repair. This article aims to comprehensively review the existing literature on the anti-microbial and osteogenic approaches utilized by hydrogels in repairing infected bones, encompassing their fabrication techniques, biocompatibility, antimicrobial efficacy, and biological activities. Additionally, the potential opportunities and obstacles in their practical implementation will be explored. Lastly, the limitations presently encountered and the prospective avenues for further investigation in the realm of hydrogel materials for the management of infected bone defects will be deliberated. This review provides a theoretical foundation and advanced design strategies for the application of hydrogel materials in the treatment of infected bone defects.

Recent Progress in antibacterial hydrogel coatings for targeting biofilm to prevent orthopedic implant-associated infections

The application of orthopedic implants for bone tissue reconstruction and functional restoration is crucial for patients with severe bone fractures and defects. However, the abiotic nature of orthopedic implants allows bacterial adhesion and colonization, leading to the formation of bacterial biofilms on the implant surface. This can result in implant failure and severe complications such as osteomyelitis and septic arthritis. The emergence of antibiotic-resistant bacteria and the limited efficacy of drugs against biofilms have increased the risk of orthopedic implant-associated infections (OIAI), necessitating the development of alternative therapeutics. In this regard, antibacterial hydrogels based on bacteria repelling, contact killing, drug delivery, or external assistance strategies have been extensively investigated for coating orthopedic implants through surface modification, offering a promising approach to target biofilm formation and prevent OIAI. This review provides an overview of recent advancements in the application of antibacterial hydrogel coatings for preventing OIAI by targeting biofilm formation. The topics covered include: (1) the mechanisms underlying OIAI occurrence and the role of biofilms in exacerbating OIAI development; (2) current strategies to impart anti-biofilm properties to hydrogel coatings and the mechanisms involved in treating OIAI. This article aims to summarize the progress in antibacterial hydrogel coatings for OIAI prevention, providing valuable insights and facilitating the development of prognostic markers for the design of effective antibacterial orthopedic implants.

A meta-analysis of the effectiveness of antibacterial bone cement in the treatment of diabetic foot skin wound infections

A meta-analysis research was implemented to appraise the effect of antibiotic bone cement (ABC) in treating infected diabetic foot wounds (IDFWs). Inclusive literature research till April 2023 was done and 1237 interconnected researches were revised. The 15 selected researches enclosed 895 IDFWs persons were in the utilized researchers' starting point, 449 of them were utilizing ABC, and 446 were in the control group. Odds ratio and 95% confidence intervals were utilized to appraise the consequence of ABC in treating IDFWs by the contentious approach and a fixed or random model. ABC had significantly lower wound healing time (MD, -9.83; 95% CI, -12.45--7.20, p < 0.001), and time to bacterial conversion of the wound (MD, -7.30; 95% CI, -10.38--4.32, p < 0.001) compared to control in IDFWs persons. However, caution needs to be taken when interacting with its values since there was a low sample size of most of the chosen research found for the comparisons in the meta-analysis.

Gentamicincoated tibial nail is an effective prevention method for fracture-related infections in open tibial fractures

Fracture-related infection (FRI) is a common complication following open tibia fracture (OTF), especially in patients with high-energy trauma or comorbidities. The use of gentamicin-coated nail (GCN) has been proposed as a local adjuvant to prevent FRI in high-risk patients.

HYPOTHESIS

The incidence of FRI is expected to be lower in OTF treated with a GCN, alongside with no detrimental effects on fracture healing time.

OBJECTIVES

This study aimed to evaluate the effectiveness of GCNs as a definitive fixation method and prophylaxis for FRI in OTFs. Secondary outcomes included non-union rates and time to healing.

METHODS

The study design was a mixed cohort, including a prospective group of patients treated with GCN (Expert Tibial Nail PROtect™, Depuy Synthes, Johnson&Johnson Company Inc, New Jersey, USA) and a retrospectively evaluated group treated with non-gentamicin-coated nail (NGCN). Patients with at least 12 months of follow-up were included. The treatment protocol consisted of timely administration of antibiotics, surgical debridement, and early soft-tissue coverage. Exclusion criteria included protocol infringement, traumatic amputation, and loss of follow-up. Statistical analysis was performed using Stata v14.0, with a significance level of p < 0.05.

RESULTS

The study included 243 patients, 104 in GCN group and 139 NGCN group. External Fixator use was higher in the NGCN group, but this did not significantly affect the FRI rate. GCN use was associated with a significantly lower incidence of FRI (2.88% GCN group vs. 15.83% NGCN group, OR 0.16, p < 0.01). Furthermore, GCN use was found to be a protective factor against tibial non-union (OR 0.41, p = 0.03). There were no adverse effects attributed to locally administered gentamycin. The NGCN cohort had a higher incidence of polytrauma, although the difference was not statistically significant. A longer time to heal as well as more FRI and Non-union according to the progression in Gustilo-Anderson classification was observed in the GCN group.

CONCLUSION

Our findings suggest that GCN is an effective prophylactic method to reduce the risk of FRI in open tibial fractures at 12-month follow-up, as well as, probably derived from this protective effect, leading to lower fracture consolidation times when compared with cases treated without GCN.

Antibiotic-laden bone cement for diabetic foot infected wounds: A systematic review and meta-analysis

Objective

A large body of literature has demonstrated the significant efficacy of antibiotic bone cement in treating infected diabetic foot wounds, but there is less corresponding evidence-based medical evidence. Therefore, this article provides a meta-analysis of the effectiveness of antibiotic bone cement in treating infected diabetic foot wounds to provide a reference basis for clinical treatment.

Methods

PubMed, Embase, Cochrane library, Scoup, China Knowledge Network (CNKI), Wanfang database, and the ClinicalTrials.gov were searched, and the search time was from the establishment of the database to October 2022, and two investigators independently. Two investigators independently screened eligible studies, evaluated the quality of the literature using the Cochrane Evaluation Manual, and performed statistical analysis of the data using RevMan 5.3 software.

Results

A total of nine randomized controlled studies (n=532) were included and, compared with the control group, antibiotic bone cement treatment reduced the time to wound healing (MD=-7.30 95% CI [-10.38, -4.23]), length of hospital stay (MD=-6.32, 95% CI [-10.15, -2.48]), time to bacterial conversion of the wound (MD=-5.15, 95% CI [-7.15,-2.19]), and the number of procedures (MD=-2.35, 95% CI [-3.68, -1.02]).

Conclusion

Antibiotic bone cement has significant advantages over traditional treatment of diabetic foot wound infection and is worthy of clinical promotion and application.

Systematic review registration

PROSPERO identifier, CDR 362293.

Analysis of the epidemiological status, microbiology, treatment methods and financial burden of hematogenous osteomyelitis based on 259 patients in Northwest China

Background

The incidence of hematogenous osteomyelitis is on the rise, and the prognosis is poor. There has been no large-scale epidemiological analysis of hematogenous osteomyelitis in the world, and the treatment method is still controversial.

Methods

A retrospective case study method was used to collect and analyze clinical data obtained from patients with hematogenous osteomyelitis in a tertiary hospital in Northwest China from January 1, 2011, to December 31, 2020. The aim of this study was to investigate the epidemiological status, microbiological characteristics, treatment and financial burden of hematogenous osteomyelitis in Northwest China to explore the therapeutic effects of different treatment methods, elucidate the epidemiological characteristics of hematogenous osteomyelitis and to provide a basis for the choice of treatment.

Results

We included 259 patients with hematogenous osteomyelitis, including 96 patients with acute hematogenous osteomyelitis and 163 patients with chronic hematogenous osteomyelitis. The cause of the disease was not obvious in most patients, the sex ratio of males to females was 1.98, and the three most common infected sites were the tibia, femur and phalanx. Regarding preoperative serum inflammatory markers, the rate of positivity for ESR was the highest at 67.58%. Among pathogenic microorganisms, Staphylococcus aureus was the most common. Regarding the financial burden, the median total cost per patient was 25,754 RMB, and medications accounted for the largest proportion of the main costs.

Conclusions

The most common pathogen associated with HO infection was MSSA. Oxacillin has good PK and PD and is recommended as the first-line drug. Some blood-borne bone infections may lead to complications, such as pulmonary infection through bacteremia, which requires early detection to avoid a missed diagnosis. Regarding surgical intervention, debridement plus absorbable calcium sulfate bone cement and calcium sulfate calcium phosphate bone cement exclusion have achieved good therapeutic effects, but they are worthy of further in-depth research. Regarding the financial burden, the median total cost per patient was 25,754 RMB. The financial burden of blood-borne osteomyelitis was lower than that of traumatic osteomyelitis. Among the main costs, drugs accounted for the largest proportion.

Long-term outcomes of lower limb post-traumatic osteomyelitis

PURPOSE

Whilst recurrence and amputation rates in post-traumatic osteomyelitis (PTOM) are described, limb specific functional outcomes are not, leading to a knowledge gap when counselling patients prior to management. We aim to investigate the patient reported outcomes (PROMS) of this patient group to provide reference for discussions with patients prior to embarking on treatment.

METHODS

Single institution cross-sectional retrospective study of all patients presenting with PTOM of the tibia/femur over a 7-year period. Alongside recurrence and amputation rates, patient reported outcomes were recorded including the lower extremity functional scale (LEFS), EQ-5D-3L and EQ-VAS.

RESULTS

Seventy-two patients (59 male; median age 46 years) were identified. Treatment was principle-based and included debridement (with Reamer-Irrigator-Aspirator (RIA) in 31/72), local antibiotics (52/72), soft tissue reconstruction (21/72) and systemic antibiotic therapy in all cases. PROMS were collected in 84% of all eligible patients at a median of 112-month post-treatment. Twelve patients experienced recurrence, whilst nine underwent amputation. The median LEFS was 60, the EQ-5D-3L index score was 0.760, and the EQ-VAS was 80. These scores are substantially lower than those seen in the general population (77, 0.856 and 82.2, respectively). LEFS was significantly higher, where RIA was utilised (69.6 vs 52.8; p = 0.02), and in those classified as BACH uncomplicated (74.4 vs 58.4; p = 0.02). EQ-5D-3L was also higher when RIA was utilised (0.883 vs 0.604; p = 0.04), with no difference in EQ-VAS scores.

CONCLUSIONS

Patients with PTOM report functional outcomes below that of the general population, even when in remission. Improved outcomes were associated with uncomplicated disease and the use of RIA.

Bone regeneration after marginal bone resection in two-stage treatment of chronic long bone infection - a combined histopathological and clinical pilot study

INTRODUCTION

In chronic bone infection, marginal bone resection avoids large and difficult to reconstruct bone defects. However, there is still a lack of knowledge on bone regeneration during chronic bone infection and bone healing capability after marginal bone resection. Therefore, the purpose of this study was to investigate the clinical and histopathological outcomes after marginal bone resection in chronic long bone infection. We hypothesized that there is a regenerative bone healing potential after marginal bone resection that results in an acceptable clinical outcome and improved pathohistological bone healing parameters during treatment.

MATERIALS AND METHODS

Nine patients were treated for chronic bone infections in a two-stage manner with marginal bone resection of the infected area and the placement of an antibiotic-loaded polymethyl methacrylate (PMMA) spacer at stage one followed by bone reconstruction at stage two combined with systemic antibiotic therapy. Comparable bone samples were harvested at the border region between vital and necrotic bone area during stage one and the identical location during stage two. Control bone samples were harvested from five healthy patients without bone infection. Clinical outcome in terms of infection eradication and bone consolidation were assessed. The phenotypic changes of osteocyte and morphological changes of lacunar-canalicular network were investigated by histological and immunohistochemical staining between the two observation periods. Furthermore, expression levels of major bone formation and resorption markers were investigated by immunohistochemical and tartrate-resistant acid phosphatase (TRAP) staining.

RESULTS

The clinical results with a follow-up of 12.9 months showed that eight of nine patients (88.9%) achieved bone consolidation after a planned two-stage procedure of marginal resection of necrotic bone and consecutive reconstruction. In four of the nine patients (44.4%), additional marginal debridements after stage two had to be performed. After marginal resection at stage one, the improved bone formation ability at stage two was demonstrated by significantly lower percentage of empty lacunae, significantly more mature osteocytes and higher BMP-2 positive cell density, whereas decreased resorption was indicated by significantly lower osteoclast density and RANKL/OPG ratio. In patients requiring additional debridement compared to patients without additional debridements, a significantly higher percentage of empty lacunae was found at stage one.

CONCLUSION

Marginal bone resection combined with local and systemic antibiotic therapy is a feasible treatment option to avoid large bone defects as bone from the marginal resection area seems to have good regenerative potential. Despite a high revision rate of 44.4%, this technique avoids large bone resection and revisions can be done by further marginal debridements.

A major trauma centre experience with gentamicin-coated tibial intramedullary nails (ETN PROtect™) in acute primary open fracture fixation and complex revision surgery

PURPOSE

Fracture-related infections (FRI) following intramedullary nailing for tibial shaft fractures remain challenging to treat with associated high patient morbidity and health care costs. Recently, antibiotic-coated nails have been introduced as a strategy to reduce implant related infection rates in high-risk patients. We present the largest single-centre case series on ETN PROtect® outcomes reporting on fracture union, infection rates and treatment complications.

METHODS

Fifty-six adult patients underwent surgery with ETN PROtect® between 01/09/17 and 31/12/20. Indications consisted of acute open fractures and complex revision cases (previous FRI, non-union surgery and re-fracture) with a mean of three prior surgical interventions. We report on patient demographics, union rates and deep infection. Minimum follow-up was one year.

RESULTS

One (1.8%) patient developed a deep surgical infection and associated non-union requiring further surgery. In addition, we identified three cases (5.4%) of aseptic non-union following facture treatment with ETN PROtect®. Of the five patients who underwent staged complex revision surgery for established FRI with ETN PROtect®, all had treatment failure with ongoing symptoms of deep infection requiring implant removal and further treatment.

CONCLUSION

Use of the ETN PROtect® nail in high-risk patients (open fractures and those initially treated with external fixation) and in those patients with aseptic non-unions, demonstrates promising outcomes in the prevention of implant-related infection. In our limited series we have failed to observe any benefit over uncoated nails, when used in treating cases of previously established FRI/osteomyelitis and would therefore advise caution in their use, especially in view of the high cost.

Chronic Osteomyelitis of the Jaw: Pivotal Role of Microbiological Investigation and Multidisciplinary Management—A Case Report

A 15-year-old girl with a history of recurrent painful orofacial swelling was diagnosed on the basis of clinical findings, histopathological examination and imaging modalities as having primary chronic osteomyelitis of the jaw. Initial microbiological samples were performed but were inconclusive. She received multiple empirical antibiotic therapies and NSAIDs for 3 years without complete remission. Only MALDI-TOF (Matrix-Assisted Laser Desorption/Ionization–Time Of Flight) analysis after additional multiple microbiological bone samples with adequate techniques yielded the final diagnosis of bacterial chronic osteomyelitis of the jaw. Its management requires a multidisciplinary approach, involving oral and maxillofacial surgeons, infectiologists and microbiologists, to limit treatment failure. Antibiotic therapy without surgery for 6 months achieved the complete radiographic resolution of the CBCT (Cone Beam Computed Tomography) and the normalization of laboratory tests. After 2 years of follow-up, no relapse had been reported. Modern microbiological investigation and sampling techniques are critical for the accurate diagnosis and management of osteomyelitis of the jaw, especially in unusual and clinically misleading forms of this infection.

Bone and Joint Infections: The Role of Imaging in Tailoring Diagnosis to Improve Patients' Care

Imaging is needed for the diagnosis of bone and joint infections, determining the severity and extent of disease, planning biopsy, and monitoring the response to treatment. Some radiological features are pathognomonic of bone and joint infections for each modality used. However, imaging diagnosis of these infections is challenging because of several overlaps with non-infectious etiologies. Interventional radiology is generally needed to verify the diagnosis and to identify the microorganism involved in the infectious process through imaging-guided biopsy. This narrative review aims to summarize the radiological features of the commonest orthopedic infections, the indications and the limits of different modalities in the diagnostic strategy as well as to outline recent findings that may facilitate diagnosis.

Impact of Healthcare-Associated Infections Connected to Medical Devices-An Update

Healthcare-associated infections (HAIs) are caused by nosocomial pathogens. HAIs have an immense impact not only on developing countries but also on highly developed parts of world. They are predominantly device-associated infections that are caused by the planktonic form of microorganisms as well as those organized in biofilms. This review elucidates the impact of HAIs, focusing on device-associated infections such as central line-associated bloodstream infection including catheter infection, catheter-associated urinary tract infection, ventilator-associated pneumonia, and surgical site infections. The most relevant microorganisms are mentioned in terms of their frequency of infection on medical devices. Standard care bundles, conventional therapy, and novel approaches against device-associated infections are briefly mentioned as well. This review concisely summarizes relevant and up-to-date information on HAIs and HAI-associated microorganisms and also provides a description of several useful approaches for tackling HAIs.

The role of low-grade infection in the pathogenesis of apparently aseptic tibial shaft nonunion

PURPOSE

Aim of this study was to determine the rate of low-grade infection in patients with primarily as aseptic categorized tibial shaft nonunion and lack of clinical signs of infection.

METHODS

In a retrospective study between 2006 and 2013, all patients who underwent revision surgery for treatment of tibial shaft nonunion without clinical evidence of infection were assessed. Bacterial cultures harvested during nonunion revision, C-reactive protein (CRP) and/or white blood cell (WBC) values at hospital admission, outcome, and epidemiological data were analyzed.

RESULTS

In 88 patients with tibial shaft nonunion without any clinical signs of infection, bacterial samples remained negative in 51 patients. In 37 patients, microbiological diagnostic studies after long-term culturing demonstrated positive bacterial cultures whereas after short-term culturing for 2 days only 17 positive cultures were observed. In 12 cases a mixed culture with 2.3 different bacteria on average was detected. Among patients with negative bacterial cultures bone healing was achieved after 13.2 months. Nonunion with positive bacterial cultures required 19 (range 2-42) months until osseous healing (p = 0.009). Furthermore, nonunion with positive bacterial cultures require statistically more surgical revisions to achieve healing (2.9 ± 0.5 vs. 1.3 ± 0.1 additional procedure; (p = 0.003). Hematological studies carried out before surgical intervention did not demonstrate significant differences in CRP values (negative vs. positive cultures: 0.3 (range 0.3-2.8) mg/dl vs. 0.5 (range 0.3-5.7) mg/dl (p = 0.181) and in WBC values (negative vs. positive cultures: 7.4 (range 3.5-11.9) /nl vs. 7.3 (range 3.7-11.1) /nl (p = 0.723). Limitations of this study may include the varying amount of the at least four samples for microbiological diagnostics as well as the circumstance that for diagnosing low-grade infection swabs and tissue samples were included in this evaluation as being equivalent.

CONCLUSION

The pathogenesis of nonunion may originate from low-grade infection even in patients without clinical signs of infection. In addition, nonunion with positive bacterial cultures require statistically more surgical revisions to achieve healing. Therefore, during any revision surgery, multiple bacterial samples are intended to be harvested for long-term culturing. Particularly, in tibial shaft nonunion following Gustilo-Anderson type III open fractures, low-grade infection should be suspected.

TRIAL REGISTRATION NUMBER

DRKS00014657.

DATE OF REGISTRATION

04/26/2018 retrospectively registered.

Antibiotic cement plate composite structure internal fixation after debridement of bone infection

An internal fixation composite structure of antibiotic cement plates was created. The aim of this study was to analyse the infection control effect of this structure when applied to treat a bone infection. We retrospectively analysed patients with bone infection admitted to our hospital between January 2013 and June 2019. After debridement, an antibiotic cement plate composite structure was used to fill and stabilize the defects. The treatment effect was evaluated at six months after surgery, and the infection control rate, factors associated with the recurrence of infection, and complications were analysed. If the patients had bone defects, the defect was repaired after infection control, and the infection control rate of all of the patients was re-evaluated at 12 months after surgery. A total of 548 patients were treated with this technique, including 418 men and 130 women. The infection sites included 309 tibias, 207 femurs, 16 radii and ulnae, 13 humeri, and 3 clavicles. After at least 6 months of follow-up, 92 patients (16.79%) had an infection recurrence and needed further treatment. The recurrence rate of the tibia was higher than that of the femur (P = 0.025). Eighty-nine out of 92 patients who relapsed underwent a second debridement with the same method, and the infection control rate after the second debridement was 94.71%. Complications included 8 cases of epidermal necrosis around the incision, 6 cases of internal fixation failure, and 30 cases of lower limb swelling. By the follow-up time of 12 months, another 6 patients had experienced recurrence of infection, and 4 cases were controlled after debridement. Finally, among all 548 cases, 7 patients remained persistently infected, and 6 underwent amputation. The infection control rate was 97.6% at the 1-year follow-up. The clinical efficacy of this new antibiotic cement plate composite structure for internal fixation after debridement of bone infection is stable and reliable.

Construction of Antimicrobial Material-Loaded Porous Tricalcium Phosphate Beads for Treatment of Bone Infections

Due to low success rates of antibiotic therapy in most osteomyelitis diseases, continuous efforts have been made to fabricate local delivery systems with high antimicrobial effects. Here, we reported a kind of ε-polylysine(PL)/Ag-loaded porous tricalcium phosphate (TCP) bead instead of antibiotics as local delivery systems for the treatment of Staphylococcus aureus-caused osteomyelitis. Such local delivery systems were prepared by the fabrication of porous TCP beads at first and then the loading of Ag and PL in turn into porous TCP beads via in situ Ag-doping and layer-by-layer methods. In vitro experiments demonstrated that the release of PL and Ag was controllable. Especially, the release dosage of Ag could be controlled to be less than 0.05 ppm 28 days later. The surface coating of PL improved the cytocompatibility and antibacterial activity of local delivery systems. In vivo experiments demonstrated that the Ag/PL-loaded porous TCP beads displayed strong antibacterial activity and good osteoconductivity, and the combination of Ag and PL was better than the use of single antibacterial materials to treat S. aureus-caused osteomyelitis. The implantation of Ag into the infected marrow had low toxicity because Ag has been integrated into the TCP grains, which could be absorbed in marrow. Therefore, the Ag/PL-loaded porous TCP beads presented potential for treating osteomyelitis, especially sequestrum-debrided osteomyelitis.

Management of surgical site infection post-open reduction and internal fixation for tibial plateau fractures

AIMS

In contrast to operations performed for other fractures, there is a high incidence rate of surgical site infection (SSI) post-open reduction and internal fixation (ORIF) done for tibial plateau fractures (TPFs). This study investigates the effect of induced membrane technique combined with internal fixation for managing SSI in TPF patients who underwent ORIF.

METHODS

From April 2013 to May 2017, 46 consecutive patients with SSI post-ORIF for TPFs were managed in our centre with an induced membrane technique. Of these, 35 patients were included for this study, with data analyzed in a retrospective manner.

RESULTS

All participants were monitored for a mean of 36 months (24 to 62). None were subjected to amputations. A total of 21 patients underwent two-stage surgeries (Group A), with 14 patients who did not receive second-stage surgery (Group B). Group A did not experience infection recurrence, and no implant or cement spacer loosening was noted in Group B for at least 24 months of follow-up. No significant difference was noted in the Lower Extremity Functional Scale (LEFS) and the Hospital for Special Surgery Knee Score (HSS) between the two groups. The clinical healing time was significantly shorter in Group B (p＜0.001). Those with longer duration of infection had poorer functional status (p＜0.001).

CONCLUSION

Management of SSI post-ORIF for TPF with induced membrane technique combined with internal fixation represents a feasible mode of treatment with satisfactory outcomes in terms of infection control and functional recovery. Cite this article: Bone Joint Res 2021;10(7):380-387.

Biofilm and its implications postfracture fixation: All I need to know

Biofilm represents an organized multicellular community of bacteria having a complex 3D structure, formed by bacterial cells and their self-produced extracellular matrix. It usually attaches to any foreign body or fixation implant. It acts as a physical protective barrier of the bacteria from the penetration of antibodies, bacteriophages, granulocytes and biocides, antiseptics, and antibiotics. Biofilm-related infections will increase in the near future. This group of surgical site infections is the most difficult to diagnose, to suppress, to eradicate, and in general to manage. Multispecialty teams involved in all stages of care are an effective way to improve results and save resources and time for the benefit of patients and the health system. Significant steps have occurred recently in the prevention and development of clever tools that we can employ in this everlasting fight with the bacteria. Herein, we attempt to describe the nature and role of the "biofilm" to the specific clinical setting of surgical site infections in the field of orthopaedic trauma surgery.

Ilizarov bone transport using an intramedullary cable transportation system in the treatment of tibial bone defects

INTRODUCTION

Segmental tibia defects remain challenging for orthopedic surgeons to treat. The aim of this study was to demonstrate bone-related and functional outcomes after treatment of complex tibial bone defects using Ilizarov bone transport with a modified intramedullary cable transportation system (CTS).

PATIENTS AND METHODS

We conducted a single-center, retrospective study including all 42 patients treated for tibial bone loss via Ilizarov bone transport with CTS between 2005 and 2018. Bone-related and functional results were evaluated according to the Association for the Study and Application of Methods of Ilizarov (ASAMI) scoring system. Complication and failure rates were determined by the patients' medical files.

RESULTS

Patients had a mean age of 45.5 ± 15.1 years. The mean bone defect size was 7.7 ± 3.4 cm, the average nonunion scoring system (NUSS) score was 59 ± 9.5 points, and the mean follow-up was 40.8 ± 24.4 months (range, 13-139 months). Complete bone and soft tissue healing occurred in 32/42 patients (76.2%). These patients had excellent (10), good (17), fair (2), and poor (3) results based on the ASAMI functional score. Regarding bone stock, 19 patients had excellent, 10 good, and 3 fair results. In total, 37 minor complications and 62 major complications occurred during the study. In 7 patients, bone and soft tissue healing occurred after CTS failure with either an induced membrane technique or classic bone transport; 3 patients underwent lower leg amputation. Patients with treatment failure were significantly older (57.6 vs. 41.8 years; p = 0.003). Charlson score and treatment failure had a positive correlation (Spearman's rho 0.43; p = 0.004).

CONCLUSION

Bone transport using both intramedullary CTS and Ilizarov ring fixation is viable for treating patients with bone loss of the tibia and complex infection or soft tissue conditions. However, a high number of complications and surgical revisions are associated with the treatment of this severe clinical entity and should be taken into account.

Bioactive glass in the treatment of chronic osteomyelitis-a valid option?

Chronic osteomyelitis continues to represent a challenge both for patients and the treating physician, especially in the presence of multiple germs. We performed a literature review assessing the current role of the indications of bioactive glass. We included studies about patients with chronic osteomyelitis that were treated with S53P4. A literature review of Medline via PubMed was performed. After the exclusion of case reports, 7 studies were included in the narrative review. Recurrence of infection was defined as the main outcome parameter. Six of 7 studies were retrospective, or case studies with a relatively small sample size (total patient number N = 274). The overall recurrence rate was 10.6%. Studies that compared the outcome of the treatment with S53P4 versus antibiotic-loaded polymethyl methacrylate (PMMA) revealed no significant difference. The data reviewed indicate that in cases of multiple bacteria and resistance to antibiotic treatment, bioglass may be a valuable treatment alternative to other forms of spacers (e.g., PMMA). This statement is limited by the fact that the number of described cases is very low. Therefore, a definitive statement of its effectiveness cannot be made at this point.

Deep infection following reconstruction of pelvic fractures: prevalence, characteristics, and predisposing risk factors

Purpose

To identify the incidence, risk factors, and treatment course of patients who developed deep infection following fixation of pelvic fractures.

Methods

Over a period of 8 years patients who underwent pelvic reconstruction in our institution and developed postoperative infection were included. Exclusion criteria were pathological fractures and infections that were not secondary to post-traumatic reconstruction. The mean time of follow-up was 43.6 months (33–144). For comparison purposes, we randomly selected patients that underwent pelvic fracture fixation from our database (control group). A logistic regression was fitted to patient characteristics including age, sex, ISS, and diabetic status.

Results

Out of 858 patients, 18 (2.1%) (12 males), with a mean age of 41 (18–73) met the inclusion criteria. The control group consisted of 82 patients with a mean age of 41 years (18–72). The mean ISS was 27.7 and 17.6 in the infection and control group, respectively. The mean time from pelvic reconstruction to the diagnosis of infection was 20 days (7–80). The median number of trips to theatre was 3 (1–16). Methicillin-resistant Staphylococcus aureus (MRSA) was the most frequently isolated organism in the years prior to 2012. Eradication was achieved in 93% of the patients. The most important risk factors for deep infection were ISS (OR 1.08, 1.03–1.13), posterior sacral approach (OR 17.03, 1.49–194.40), and diabetes (OR 36.85, 3.54–383.70).

Conclusion

In this retrospective case–control study, deep infection following pelvic trauma was rare. A number of patient-, injury- and surgery-related factors have shown strong correlation with this serious complication.

The AMANDUS Project PART II-Advanced Microperfusion Assessed Non-Union Diagnostics with Contrast-Enhanced Ultrasound (CEUS): A Reliable Diagnostic Tool for the Management and Pre-operative Detection of Infected Upper-Limb Non-unions

The management of upper-limb non-unions can be challenging, especially when infection is existent. Thus, pre-operative detection of infection plays a relevant role in non-union treatment. This study investigated in a large cohort the diagnostic potential of contrast-enhanced ultrasound (CEUS) as stand-alone method for differentiating between aseptic and infected upper-limb non-unions. Osseous perfusion of 50 upper-extremity non-unions (radius/ulna, n = 20; humerus, n = 22; clavicle, n = 8) was prospectively assessed with CEUS before revision surgery. The perfusion was quantified via time-intensity curves and peak enhancement (in arbitrary units). Significant perfusion differences between aseptic and infected non-unions could be detected (peak enhancement, p < 0.001). The sensitivity and specificity for the detection of infected upper-limb non-unions were 80% and 94.3% (cutoff peak enhancement: 130.8 arbitrary units). CEUS reliably differentiates between aseptic and infected upper-limb non-unions. Consequently, CEUS should be integrated into the daily diagnostic routine algorithm to plan non-union revision surgery more precisely as a single- or multi-step procedure.

Garre’s Osteomyelitis of the Mandible: Report of 2 Cases

BACKGROUND: Garre’s osteomyelitis is a rare type of chronic osteomyelitis that mainly affects children and young adults. This disease is commonly associated with an odontogenic infection resulting from dental caries. CASE REPORTS: This article describes two case reports of young boys with Garre’s osteomyelitis of mandible caused by odontogenic infection. RESULTS: The cases were managed by extraction followed by antibiotics and the healing was achieved uneventfully.

Multidisciplinary management of the bone and joint infection complicating treatment of an open fracture of the lower limb

Bone and joint infections (BJI) of the lower limb can cause functional sequelae and in some cases have an impact on patient's life prognostic. One of the main objectives of multidisciplinary consultation team meetings (MTM) in the treatment of bone and joint infections is to provide an appropriate medical-surgical care, pooling skills of different organ specialists: infectious disease physicians, microbiologists, orthopedic surgeons and plastic surgeons. Treatment is based on aggressive debridement, bone stabilization, adequate antibiotic therapy, long-term coverage of the loss of skin substance and close clinical monitoring. The authors present their multidisciplinary diagnostic and therapeutic approaches to BJI complicating an open fracture at a referent center in the management of complex bone and joint infections.

[Masquelet technique combined with flap transplantation for infectious bone and soft tissue defects of lower leg]

Objective

To investigate the effectiveness of Masquelet technique combined with flap transplantation in treatment of infectious bone and soft tissue defects of the lower leg.

Methods

Between January 2013 and January 2017, 35 cases of infectious bone and soft tissue defects of lower leg were treated with Masquelet technique combined with flap transplantation. There were 21 males and 14 females, with an average of 31.5 years (mean, 25-55 years). All patients were tibial fractures caused by trauma and the infections occurred after debridement or internal fixation. The time from injury to admission was 1 to 6 months, with an average of 3.2 months. Defect located at the proximal leg in 11 cases, the middle leg in 11 cases, and the distal leg in 13 cases. The length of tibia defect after debridement ranged from 5.6 to 11.2 cm, with an average of 7.1 cm. The size of soft tissue defect ranged from 14.2 cm×6.9 cm to 17.3 cm×8.7 cm. Bacterial culture of purulent secretion of wound was positive in 18 cases. After debridement, the bone cement was used to fill the bone defect and the flap transplantation was used to repair the wound. The bone cement was taken out at 8 to 12 weeks after the one-stage operation, and the bone defect was repaired with autogenous iliac bone or combined with artificial bone.

Results

Three cases had necrosis at the distal edge of the flap after one-stage operation, and survived after dressing change. The other flaps survived successfully, and the wounds healed by first intention. All incisions healed by first intention after two-stage operation. All patients were followed up 24-32 months, with an average of 27 months. The color of the flap was similar to that of the surrounding normal tissue, and its texture was good. X-ray reexamination showed that all bone defects healed after 6-8 months, with an average of 6.7 months. At 9 months after two-stage operation, according to the revised Edwards tibial fracture evaluation standard, 19 cases were excellent, 14 cases were good, and 2 cases were poor, the excellent and good rate was 94.3%. The American Orthopedic Ankle Association (AOFAS) score was 60-98, with an average of 81.3. And 21 cases were excellent, 11 were good, and 3 were fair, with an excellent and good rate of 91.4%.

Conclusion

Masquelet technique combined with flap transplantation is an effective treatment for infectious bone and soft tissue defects of lower leg.

Imaging and Laboratory Workup for Hand Infections

Hand infections can lead to significant morbidity if not treated promptly. Most of these infections, such as abscesses, tenosynovitis, cellulitis, and necrotizing fasciitis, can be diagnosed clinically. Laboratory values, such as white blood cell count, erythrocyte sedimentation rate, C-reactive protein, and recently, procalcitonin and interleukin-6, are helpful in supporting the diagnosis and trending disease progression. Radiographs should be obtained in all cases of infection. Ultrasound is a dynamic study that can provide quick evaluation of deeper structures but is operator dependent. Computed tomographic and MRI studies are useful for evaluating deep space or bony infections and preoperative surgical planning.

Real-World Use of Oritavancin for the Treatment of Osteomyelitis

Osteomyelitis is a difficult-to-treat disease that can require both surgical debridement and a prolonged course of antimicrobial therapy. Current standard of care for the antimicrobial treatment of osteomyelitis is fraught with multiple challenges and limitations. Patients typically require the insertion of an indwelling catheter for single or multiple daily intravenous antibiotic infusions for up to 6 weeks. Currently, there are treatment guidelines for only vertebral osteomyelitis, indicating the complexity of the condition. Oritavancin is a long-acting, second-generation lipoglycopeptide, administered intravenously once per week, which has potential to be a useful alternative in the treatment of osteomyelitis. This article reviews occurrence and outcomes of off-label oritavancin use for treatment of osteomyelitis as described in case reports. Analysis included 23 patients treated for osteomyelitis with single- or multiple-dose oritavancin. Overall, clinical cure or improvement was achieved in 87% of patients, and adverse events were mild and reported in only two patients. Clinical efficacy was demonstrated in 81.8% of methicillin-resistant Staphylococcus aureus (MRSA), 71.4% of methicillin-sensitive S. aureus (MSSA), 50% of vancomycin-resistant Enterococcus (VRE), and in the single case of Streptococcus pyogenes. Oritavancin has shown efficacy against Gram-positive pathogens in osteomyelitis, and offers a possible outpatient treatment option for osteomyelitis patients. Future studies are needed to determine dosing frequency in osteomyelitis patients.

Antibiotic treatment regimens for bone infection after debridement: a study of 902 cases

BACKGROUND

Our aim was to investigate the clinical efficacy and complications of antibiotic treatment regimens for patients with bone infection.

METHODS

We retrospectively analysed patients with bone infection admitted to our hospital between March 2013 and October 2018. After surgical debridement was performed, the patients were divided into three groups: IV group (intravenous antibiotics for 2 weeks); oral group (intravenous antibiotics for 2 weeks followed by oral antibiotics for 4 weeks); and rifampicin group (intravenous antibiotics for 2 weeks followed by oral antibiotics plus rifampicin for 4 weeks). The infection control rate and complications were compared among the three groups.

RESULTS

A total of 902 patients were enrolled. The infection sites included 509 tibias, 228 femurs, 32 humeri, 23 radii and ulnae, 40 calcanei, and 47 miscellaneous sites, as well as 23 multiple-site infections. After at least 6 months of follow-up, 148 (16.4%) patients had an infection recurrence. The recurrence rate of the IV group was 17.9%, which was not significantly higher than the recurrence rates of the oral group (10.1%) and rifampicin group (10.5%), P = 0.051. The incidence of abnormal alanine aminotransferase (ALT) levels in the IV group was 15.1%, which was lower than that in the oral group (18.0%) and rifampicin group (27.4%), P = 0.026. The rates of proteinuria in the three groups were 3.2, 4.5, and 9.3%, respectively, P = 0.020.

CONCLUSIONS

After debridement of bone infection, short-term antibiotic treatment regimens might offer similar rates of infection eradication while avoiding the risk of renal and hepatic damage associated with prolonged antibiotic use.

THE LEVEL OF CLINICAL RELEVANCE

Stage III.

Acute and chronic infection: Is there a gold standard for management of the wound and bone defect?

Acute and chronic infections with bone involvement remain a challenge to manage. They pose a significant burden to the patient, the treating surgeon, and society. Multidisciplinary team involvement is mandatory for a successful outcome. Application of a gold standard approach is not possible due to the high heterogeneous patient population and the variable degree of severity of soft tissue and bone involvement. The mainstay of treatment remains the conversion of a septic environment to an aseptic one with aggressive debridement of the affected soft tissues and bone. Reconstruction of the soft tissue defect can be achieved using modern microsurgical techniques, whereas the induced membrane and distraction osteogenesis (bone transport) are currently the 2 most commonly used treatment modalities for bone loss.

The safest approach to deal successfully with this multifaceted clinical pathology is to always follow well-established principles of management and adapt treatment to the personalized needs of the patient.

Management of Infected Bone Defects of the Lower Extremities by Three-Stage Induced Membrane Technique

BACKGROUND Infected bone defects are therapeutic challenges. Although the induced membrane technique has been used for this problem, there is a 3% to 20.7% failure to eradicate infection, and there have been few reports about its use in tuberculous infection. We present our three-stage induced membrane technique (TSIMT) for treating infected bone defects of the lower extremity. MATERIAL AND METHODS Forty-one adult patients with infected bone defects of the lower extremities treated by TSIMT were included in a retrospective case-series study between January 2013 and June 2018. The clinical, imaging and laboratory assessment outcomes were analyzed. RESULTS In the first stage, 3 patients had ankle tuberculous bone defects and 17 patients underwent 2-4 debridements. In the second stage, the average bone defect was 6.0 cm; 1 patient needed an anterolateral thigh flap to cover the wound. In the third stage, 10 patients underwent autograft mixed allograft, and 18 cases used internal fixation. The mean follow-up period was 23.3 months. All patients achieved bone union and clinical eradication of infection. Changes in Lower Extremity Functional Scale (LEFS) scores after 1 year of TSIMT and bone union time are associated with advanced age, longer duration of infected bone defects, active smoking, and external fixation (p<0.05), but are not dependent on bone defect size, debridement times, type of bone graft, or spacer-placing time (p>0.05). CONCLUSIONS TSIMT is effective in treating infected bone defects of the lower extremities. Advanced age, longer duration of infected bone defects, active smoking, and external fixation adversely affect bone union and recovery of infected extremities in a limited time span.

An antibiotic cement-coated locking plate as a temporary fixation for treatment of infected bone defects: a new method of stabilization

Background

The induced membrane technique has achieved good clinical results in the treatment of infected bone defects, and external fixation is the main method, but it causes inconvenience and complications in patients. In this study, our objective was to investigate the outcomes of using an antibiotic cement-coated locking plate as a temporary internal fixation in the first stage of the surgical induced membrane technique for treating extremities with infected bone defects.

Methods

We retrospectively analysed patients with lower extremity infected bone defects in our department between January 2013 and December 2017. All patients were treated with the induced membrane technique. In the first stage, the defects were stabilized with an antibiotic cement-coated locking plate as a temporary fixation after debridement, and polymethyl methacrylate cement was implanted to induce the formation of a membrane. In the second stage, bone grafting rebuilt the bone defects after infection control, and the temporary fixation was changed to a stronger fixation.

Results

A total of 183 patients were enrolled, with an average follow-up duration of 32.0 (12–66) months. There were 154 males and 29 females with an average age of 42.8 (10–68) years. The infection sites included 81 femurs, 100 tibias and 2 fibulas. After the first stage of treatment (infection control), 16 (8.7%) patients had recurrence of infection. In terms of the incidence of complications, 4 patients had poor wound healing, 2 patients had fixation failure and 1 patient had femoral fracture due to a fall. After the second stage of treatment (bone reconstruction), there were 24 (13.1%) recurrences of infection, with a mean time of 9.9 months (range 0.5 to 36). Among them, 18 patients underwent bone grafting after re-debridement, 6 received permanent placement of antibiotic bone cement after debridement and 2 patients refused further treatment and chose amputation. Bone healing was achieved in 175 (95.9%) patients at the last follow-up, and the average time to bone union was 5.4 (4–12) months.

Conclusions

Antibiotic cement-coated locking plates have good clinical effects in the control of bone infection, but attention must be paid to the possible difficulty of skin coverage when applied in calves.

Detection of extremity chronic traumatic osteomyelitis by machine learning based on computed-tomography images: A retrospective study

Despite the availability of a series of tests, detection of chronic traumatic osteomyelitis is still exhausting in clinical practice. We hypothesized that machine learning based on computed-tomography (CT) images would provide better diagnostic performance for extremity traumatic chronic osteomyelitis than the serological biomarker alone. A retrospective study was carried out to collect medical data from patients with extremity traumatic osteomyelitis according to the criteria of musculoskeletal infection society. In each patient, serum levels of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and D-dimer were measured and CT scan of the extremity was conducted 7 days after admission preoperatively. A deep residual network (ResNet) machine learning model was established for recognition of bone lesion on the CT image. A total of 28,718 CT images from 163 adult patients were included. Then, we randomly extracted 80% of all CT images from each patient for training, 10% for validation, and 10% for testing. Our results showed that machine learning (83.4%) outperformed CRP (53.2%), ESR (68.8%), and D-dimer (68.1%) separately in accuracy. Meanwhile, machine learning (88.0%) demonstrated highest sensitivity when compared with CRP (50.6%), ESR (73.0%), and D-dimer (51.7%). Considering the specificity, machine learning (77.0%) is better than CRP (59.4%) and ESR (62.2%), but not D-dimer (83.8%). Our findings indicated that machine learning based on CT images is an effective and promising avenue for detection of chronic traumatic osteomyelitis in the extremity.

Pulsed electromagnetic field (PEMF): A potential adjuvant treatment for infected nonunion

Infected nonunion is still a challenge for orthopaedic surgeons. The goal of treatment is to eliminate infection and achieve bone union. Surgery is the only effective method currently. However, it is invasive and the results are still unsatisfactory. Therefore, seeking a noninvasive and effective method to resolve infected nonunion is necessary. Pulsed electromagnetic field (PEMF) has been used for the treatment of nonunion for more than 40 years. PEMF could promote bone formation at tissue, cell and subcellular levels. Furthermore, our study showed that PEMF had bactericidal effect. The hypothesis we proposed herein is that PEMF may be an adjuvant treatment for infected nonunion by controlling infection and inducing bone formation.

Chinese expert consensus on diagnosis and treatment of infection after fracture fixation

Currently, accurate diagnosis and successful treatment of infection after fracture fixation (IAFF) still impose great challenges. According to the onset of infection symptoms after implantation, IAFF is classified as early infection (<2 weeks), delayed infection (2∼10 weeks) and late infection (>10 weeks). Confirmation of IAFF should be supported by histopathological tests of intraoperative specimens which confirm infection, cultures from at least two suspected infection sites which reveal the same pathogen, a definite sinus or fistula which connects directly the bone or the implant, and purulent drainage from the wound or presence of pus during surgery. Diagnosis of IAFF is built on comprehensive assessment of medical history, clinical signs and symptoms of the patient, and imaging and laboratory tests. The gold standard of diagnosis is histopathological tests. Treatment of IAFF consists of radical debridement, adequate irrigation, implant handling, systematic and local antibiotics, reconstruction of osseous and/or soft tissue defects, and functional rehabilitation of an affected limb. Early accurate diagnosis and appropriate treatment of IAFF play a key role in increasing the cure rate, reducing infection recurrence and disability risk, restoring limb function and improving quality of life of the patient.

Getting it right first time: The importance of a structured tissue sampling protocol for diagnosing fracture-related infections

INTRODUCTION

Fracture-related infection (FRI) is an important complication following surgical fracture management. Key to successful treatment is an accurate diagnosis. To this end, microbiological identification remains the gold standard. Although a structured approach towards sampling specimens for microbiology seems logical, there is no consensus on a culture protocol for FRI. The aim of this study is to evaluate the effect of a structured microbiology sampling protocol for fracture-related infections compared to ad-hoc culture sampling.

METHODS

We conducted a pre-/post-implementation cohort study that compared the effects of implementation of a structured FRI sampling protocol. The protocol included strict criteria for sampling and interpretation of tissue cultures for microbiology. All intraoperative samples from suspected or confirmed FRI were compared for culture results. Adherence to the protocol was described for the post-implementation cohort.

RESULTS

In total 101 patients were included, 49 pre-implementation and 52 post-implementation. From these patients 175 intraoperative culture sets were obtained, 96 and 79 pre- and post-implementation respectively. Cultures from the pre-implementation cohort showed significantly more antibiotic use during culture sampling (P =  0.002). The post-implementation cohort showed a tendency more positive culture sets (69% vs. 63%), with a significant difference in open wounds (86% vs. 67%, P =  0.034). In all post-implementation culture sets causative pathogens were cultured more than once per set, in contrast to pre-implementation. Despite stricter tissue sampling and culture interpretation criteria, the number of polymicrobial infections was similar in both cohorts, approximately 29% of all culture sets and 44% of all positive culture sets. Significantly more polymicrobial cultures were found in early infections in the post-implementation cohort (P =  0.048). This indicates a better yield in the new protocol.

CONCLUSION

A standardised protocol for intraoperative sampling for bacterial identification in FRI is superior than an ad-hoc approach. It has a positive effect on both surgeon and microbiologist by increasing awareness about the problem at hand. This resulted in more microbiologically confirmed infections and more certainty when identifying causative pathogens.

Clinical pathologies of bone fracture modelled in zebrafish

Reduced bone quality or mineral density predict susceptibility to fracture and also attenuate subsequent repair. Bone regrowth is also compromised by bacterial infection, which exacerbates fracture site inflammation. Because of the cellular complexity of fracture repair, as well as genetic and environmental influences, there is a need for models that permit visualisation of the fracture repair process under clinically relevant conditions. To characterise the process of fracture repair in zebrafish, we employed a crush fracture of fin rays, coupled with histological and transgenic labelling of cellular responses; the results demonstrate a strong similarity to the phased response in humans. We applied our analysis to a zebrafish model of osteogenesis imperfecta (OI), which shows reduced bone quality, spontaneous fractures and propensity for non-unions. We found deficiencies in the formation of a bone callus during fracture repair in our OI model and showed that clinically employed antiresorptive bisphosphonates can reduce spontaneous fractures in OI fish and also measurably reduce fracture callus remodelling in wild-type fish. The csf1ra mutant, which has reduced osteoclast numbers, also showed reduced callus remodelling. Exposure to excessive bisphosphonate, however, disrupted callus repair. Intriguingly, neutrophils initially colonised the fracture site, but were later completely excluded. However, when fractures were infected with Staphylococcus aureus, neutrophils were retained and compromised repair. This work elevates the zebrafish bone fracture model and indicates its utility in assessing conditions of relevance to an orthopaedic setting with medium throughput.

This article has an associated First Person interview with the first author of the paper.

Summary: The effect of osteogenesis imperfecta, bisphosphonate treatment and bacterial infection on phases of bone fracture repair are determined using a zebrafish fracture model.

The AMANDUS Project-Advanced Microperfusion Assessed Non-Union Diagnostics With Contrast-Enhanced Ultrasound (CEUS) for the Detection of Infected Lower Extremity Non-Unions

The pre-operative determination of infection plays a decisive role in non-union treatment. This study investigated in a large cohort the diagnostic potential of contrast-enhanced ultrasound (CEUS) as stand-alone method for the differentiation between aseptic and infected non-unions. Of 109 patients with lower extremity non-unions (tibia n = 78, femur n = 31) osseous perfusion with CEUS was prospectively assessed before revision surgery. The perfusion was quantified via time-intensity curves and peak enhancement (PE) (arbitrary unit [au]). Significant perfusion differences between aseptic and infected non-unions were evident (PE, p < 0.001). The sensitivity and specificity for the detection of infected tibial and femoral non-unions could be determined with 85.1% and 88.7% (cutoff PE: 81.2 au). CEUS illustrates tibial and femoral non-union perfusion in real time and discriminates reliably between aseptic and infected non-unions. Consequently, when CEUS is integrated into the diagnostic routine algorithm, non-union revision surgery can be planned more accurately as a single or multistep procedure.

Evaluation of the clinical use of the ETN PROtect® in non-union therapy

INTRODUCTION

Non-union of a long bone fracture remains a challenge in orthopaedic and trauma surgery. In the current study, we sought to determine the clinical effectiveness of tibial non-union treatment utilizing an antibiotic-coated intramedullary nail (Expert Tibia Nail (ETN) PROtect®) regarding prevention and treatment of infection and the clinical outcome.

PATIENTS AND METHODS

36 patients suffering from tibial non-unions that were treated with the ETN PROtect® in the course of non-union treatment between February 2010 and March 2015 were included in this clinical observational study. Clinical and radiological examinations were performed preoperatively as well as 4, 6 and 12 weeks and 6 and 12 months postoperatively as part of a standardized follow-up program. Data regarding perioperative complications, weight-bearing capacity, radiological signs of consolidation and subjective health status were assessed at each time point. Laboratory parameters such as C-reactive protein (CRP) and leukocyte count were collected preoperatively in order to assess the patients' risk profile for infection.

RESULTS

Patients had an average of 6.2 previous surgeries and 22 patients (61.1%) had a positive bacterial culture from intraoperatively removed tissue during the first operative treatment. 29 patients (80.6%) achieved full weight-bearing after an average of 7.7 months, furthermore 80.6% of patients achieved osseous consolidation. 3 deep infections occurred, including one amputation. Subjective health status increase based on the SF-12 questionnaire during our follow-up program.

CONCLUSION

The results from the current study indicate that the use of the ETN PROtect® in the applied non-union therapy has a high clinical effectiveness regarding osseous consolidation and time to weight bearing. In addition, the use of gentamicin-coated nails in the treatment of tibial non-unions might contribute to both successful treatment of the underlying infection and prevention of perioperative infection. The gentamicin-coated nail may serve as a beneficial adjunct treatment in the applied non-union therapy in addition to all established techniques in the treatment of infected non-unions.

Outcomes of Vacuum Sealing Drainage Treatment Combined with Skin Flap Transplantation and Antibiotic Bone Cement on Chronic Tibia Osteomyelitis: A Case Series Study

BACKGROUND Chronic osteomyelitis is one of the currently refractory diseases. The aim of this study is to discuss the method and curative effects of vacuum sealing drainage (VSD) treatment combined with skin flap transplantation and antibiotic bone cement for chronic tibia osteomyelitis. MATERIAL AND METHODS For this study, 18 cases of open fracture secondary chronic tibia osteomyelitis were selected. After the granulation tissue of the wound surface became fresh and infection was controlled, the wound surface was repaired with a medial head of gastrocnemius transfer flap or a myofascial and cutaneous island pedicle flap with a collateral vessel nourished by the retrograde sural nerve. VSD combined with focus debridement and antibiotic bone cement filling was conducted. After inflammation was completely regulated, elective bone cement extraction, bone grafting, and internal fixation were performed. Within 2 to 3 years of follow-up post-surgery, the satisfaction and recurrence rates were evaluated. The patients' pre-operative and post-operative recovery of limb functions were compared according to the Enneking scoring system. RESULTS The patients did not suffer from osteomyelitis recurrence, with the exception of 1 case that manifested osteomyelitis recurrence and recovered through surgical treatment within the period of follow-up. The satisfaction and recurrence rates of these study cases post-surgery were 94.4% and 5.6%, respectively. The average functional recovery post-surgery was 81.5% of normal function. CONCLUSIONS Vacuum sealing drainage combined with skin flap transplantation and antibiotic bone cement is an effective treatment for chronic tibia osteomyelitis.

The effect of early broad-spectrum versus delayed narrow-spectrum antibiotic therapy on the primary cure rate of acute infection after osteosynthesis

Purpose

Infection near metal implants is a problem that presents challenging treatment dilemmas for physicians. The aim of this study was to analyse the efficacy of two treatment protocols for acute fracture-related infections.

Methods

Seventy-one patients in two level-1 trauma centres in the Netherlands were retrospectively included in this study. These trauma centres had different standardised protocols for acute infection after osteosynthesis: 39 patients were selected from protocol A and 32 from protocol B. Both protocols involve immediate surgical debridement and soft tissue coverage, but differ in antibiotic approach: (A) immediate empirical combination antibiotic therapy with rifampicin, or (B) postponed (1–5 days) targeted antibiotic therapy. The primary outcome of these protocols was success, defined as a fracture healing in the absence of infection. The secondary outcome was antibiotic resistance patterns. Logistic regression was conducted on patients and treatment-related factors in association with primary success.

Results

Primary success was achieved in 72% of protocol A patients, in 47% of those in protocol B (P = 0.033), and with prolongation of treatment success was achieved in 90% and 78% of patients, respectively. Protocol A exhibited a better primary success rate (adjusted OR 3.45, CI 1.13–10.52) when adjusted for age and soft tissue injury. There was no significant difference in antibiotic resistance between the two protocols.

Conclusion

Both protocols yielded high overall success rates. Immediate empirical antibiotics can be used safely without additional bacterial resistance and may contribute to increased success rates.

Chronic Osteomyelitis Revisited: A Case Report

Chronic osteomyelitis treatment is always a challenge to orthopaedic surgeons which requires great dedication and perseverance. We report a successful limb salvage case of a 46-year-old man who suffered from a left tibia chronic osteomyelitis with soft tissue defect. The treatment approach was a thorough wound debridement of devitalized tissues and necrotized bone, commencement of culture-directed antibiotics, reconstruction with vascularized osteomyocutaneous fibula flap, and skeletal stabilization with internal fixation. As compared to below knee amputation, the result we obtained in this case is more promising with regard to mobility and function.

Diagnosis of peripheral bone and prosthetic joint infections: overview on the consensus documents by the EANM, EBJIS, and ESR (with ESCMID endorsement)

OBJECTIVES

Peripheral bone infection (PBI) and prosthetic joint infection (PJI) are two different infectious conditions of the musculoskeletal system. They have in common to be quite challenging to be diagnosed and no clear diagnostic flowchart has been established. Thus, a conjoined initiative on these two topics has been initiated by the European Society of Radiology (ESR), the European Association of Nuclear Medicine (EANM), the European Bone and Joint Infection Society (EBJIS), and the European Society of Clinical Microbiology and Infectious Diseases (ESCMID). The purpose of this work is to provide an overview on the two consensus documents on PBI and PJI that originated by the conjoined work of the ESR, EANM, and EBJIS (with ESCMID endorsement).

METHODS AND RESULTS

After literature search, a list of 18 statements for PBI and 25 statements for PJI were drafted in consensus on the most debated diagnostic challenges on these two topics, with emphasis on imaging.

CONCLUSIONS

Overall, white blood cell scintigraphy and magnetic resonance imaging have individually demonstrated the highest diagnostic performance over other imaging modalities for the diagnosis of PBI and PJI. However, the choice of which advanced diagnostic modality to use first depends on several factors, such as the benefit for the patient, local experience of imaging specialists, costs, and availability. Since robust, comparative studies among most tests do not exist, the proposed flowcharts are based not only on existing literature but also on the opinion of multiple experts involved on these topics.

KEY POINTS

• For peripheral bone infection and prosthetic joint infection, white blood cell and magnetic resonance imaging have individually demonstrated the highest diagnostic performance over other imaging modalities. • Two evidence- and expert-based diagnostic flowcharts involving variable combination of laboratory tests, biopsy methods, and radiological and nuclear medicine imaging modalities are proposed by a multi-society expert panel. • Clinical application of these flowcharts depends on several factors, such as the benefit for the patient, local experience, costs, and availability.

Osteomyelitis Caused by Carbapenemase-Producing Klebsiella Pneumoniae: A Diagnosis to Consider in Patients with Hematologic Malignancies and Stem Cell Transplant Recipients

Case series

Patients: Female, 49 • Female, 47

Final Diagnosis: Osteomyelitis by Klebsiella pneumoniae

Symptoms: Fever

Medication: —

Clinical Procedure: —

Specialty: Hematology

Consensus document for the diagnosis of peripheral bone infection in adults: a joint paper by the EANM, EBJIS, and ESR (with ESCMID endorsement)

INTRODUCTION

In adults with a suspicion of peripheral bone infection, evidence-based guidelines in choosing the most accurate diagnostic strategy are lacking.

AIM AND METHODS

To provide an evidence-based, multidisciplinary consensus document on the diagnostic management of adult patients with PBIs, we performed a systematic review of relevant infectious, microbiological, orthopedic, radiological, and nuclear medicine literature. Delegates from four European societies (European Bone and Joint Infection Society, European Society of Microbiology and Infectious Diseases, European Society or Radiology, and European Association of Nuclear Medicine) defined clinical questions to be addressed, thoroughly reviewed the literature pertinent to each of the questions, and thereby evaluated the diagnostic accuracy of each diagnostic technique. Inclusion of the papers per statement was based on a PICO (Population/problem - Intervention/indicator - Comparator - Outcome) question following the strategy reported by the Oxford Centre for Evidence-based Medicine. For each statement, the level of evidence was graded according to the 2011 review of the Oxford Centre for Evidence-based Medicine. All approved statements were addressed taking into consideration the available diagnostic procedures, patient acceptance, tolerability, complications, and costs in Europe. Finally, a commonly agreed-upon diagnostic flowchart was developed.

The Dilemma of Chronic Recurrent Multifocal Osteomyelitis

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare idiopathic inflammatory disease that affects mainly children and young adults, resulting in significant morbidity especially if not diagnosed early. The clinical signs and symptoms are nonspecific, with a consequential delay in diagnosis. Radiological and histopathological criteria are important for its definition. Two cases of CRMO are reported, highlighting the diagnostic challenge and demonstrating the importance of timely investigations.