The management of osteomyelitis in the adult

Single versus two-stage management of long-bone chronic osteomyelitis in adults: a systematic review and meta-analysis

BACKGROUND

Chronic osteomyelitis is a debilitating bone infection, characterized by a persistent infection over months to years, poses diagnostic and therapeutic challenges due to its insidious nature and potential for severe bone and soft tissue destruction. This systematic review and meta-analysis aims to review the literature on the treatment of chronic osteomyelitis in long bones and assess cure rates in single versus two-stage surgery.

METHODS

Following the PRISMA guidelines and registered with PROSPERO (ID: CRD42021231237), this review included studies that reported on the management of chronic osteomyelitis in long bones using either a planned one-stage or two-stage surgical approach in adult patients. Databases searched included Medline, Embase, Web of Science, CINAHL, HMIC, and AMED, using keywords related to osteomyelitis, long bones, and surgical management. Eligibility criteria focused on adults with chronic osteomyelitis in long bones, with outcomes reported after a minimum follow-up of 12 months. The meta-analysis utilized the random-effects model to pool cure rates.

RESULTS

The analysis included 42 studies with a total of 1605 patients. The overall pooled cure rate was 91% (CI 95%) with no significant difference observed between single-stage and two-stage surgeries (X2 = 0.76, P > 0.05). Complications were reported in 26.6% of cases in single-stage procedures and 27.6% in two-stage procedures, with prolonged wound drainage noted as a common issue. Dead space management techniques varied across studies, with antibiotic-loaded calcium sulphate beads used in 30.4% of cases.

CONCLUSION

This meta-analysis reveals no significant difference in cure rates between single and two-stage surgical treatments for chronic osteomyelitis in long bones, supporting the efficacy of both approaches. The current treatment strategy should include a combination of debridement, dead space management using local and systematic antibiotics and soft tissue reconstruction if necessary.

Histograms of computed tomography values in differential diagnosis of benign and malignant osteogenic lesions

BACKGROUND

The use of histogram analysis of computed tomography (CT) values is a potential method for differentiating between benign osteoblastic lesions (BOLs) and malignant osteoblastic lesions (MOLs).

PURPOSE

To explore the diagnostic efficacy of histogram analysis in accurately distinguishing between BOLs and MOLs based on CT values.

MATERIAL AND METHODS

A total of 25 BOLs and 25 MOLs, which were confirmed through pathology or imaging follow-up, were included in this study. FireVoxel software was used to process the lesions and obtain various histogram parameters, including mean value, standard deviation, variance, coefficient of variation, skewness, kurtosis, entropy value, and percentiles ranging from 1st to 99th. Statistical tests, such as two independent-sample t-tests and the Mann-Whitney U test with Bonferroni correction, were employed to compare the differences in histogram parameters between BOLs and MOLs. A receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic efficacy of each parameter.

RESULTS

Significant differences were observed in several histogram parameters between BOLs and MOLs, including the mean value, coefficient of variation, skewness, and various percentiles. Notably, the 25th percentile demonstrated the highest diagnostic efficacy, as indicated by the largest area under the curve in the ROC curve analysis.

CONCLUSION

Histogram analysis of CT values provides valuable diagnostic information for accurately differentiating between BOLs and MOLs. Among the different parameters, the 25th percentile parameter proves to be the most effective in this discrimination process.

Can jaw bone healed from chronic sclerosing osteomyelitis be considered healthy when planning dental implants? Case report with 20-year follow-up

Introduction and importance

Extraction of mandibular third molars can lead to complications such as chronic sclerosing osteomyelitis (CSO), an inflammatory bone marrow disease that tends to progress. CSO involves the cortical plates and often the periosteal tissues and is caused by a variety of microorganisms, including Corynebacterium spp. The treatment of chronic osteomyelitis (CO) and CSO remains challenging, as there is no universal treatment protocol. This case report investigated whether jaw bone that has healed from chronic sclerosing osteomyelitis can be considered healthy bone when planning dental implants.

Case presentation

A 21-year-old Caucasian woman developed CO and CSO after third molar surgery.

Clinical discussion

A combination of alveolar ridge bone resection, extraction of teeth 47-32, and long-term specific antibiotic therapy against Corynebacterium spp. was administered. An attempt at preprosthetic alveolar ridge reconstruction with an anterior superior iliac crest bone graft resulted in graft failure and the patient refused further harvesting procedures. Implantation in the intraforaminal zone also resulted in the loss of two implants after loading. Finally, inferior alveolar nerve transposition resulted in the successful reimplantation of two implants, which were fully functional almost 11 years later.

Conclusion

This case report presents the treatment history of this patient. With a longitudinal observation period of greater than 20 years, the results of this case demonstrate the successful treatment of bone with CO, CSO, and Corynebacterium spp. infection. Following the removal of infected bone, radical debridement, and long-term antibiotic therapy, bone health was restored.

Etiology and antimicrobial resistance patterns in chronic osteomyelitis of the tibia: an 11-year clinical experience

PURPOSE

To analyze changes in tendency of etiology and of antimicrobial resistance patterns to most common local and systemic antibiotics in chronic osteomyelitis of the tibia (COM-T) in a Level I trauma center over an 11-year period.

METHODS

A retrospective review including all patients with COM-T who were surgically treated from January 2009 to December 2019. Patients were divided into two period groups: 2009-2014 and 2015-2019. Microbiologic etiology was analyzed. Bacterial resistance patterns evaluation was based on the Magiorakos et al. classification, including proportions of multidrug-resistant organisms (MDROs, acquired non-susceptibility to at least one agent in three or more antimicrobial categories), extensively drug-resistant (XDR) and pan drug-resistant (PDR) organisms encountered.

RESULTS

A total of 173 episodes of COM-T were identified. Monomicrobial infections represented 47.4% of all cases, while 28.3% had polymicrobial infections. Negative deep-bone cultures were identified in 24.3% of the patients. The most commonly isolated microorganisms were coagulase-negative Staphylococci (24.5%) and S. aureus (20.5%). No differences were found when comparing Gram-positive infections between periods (58.3% for 2009-2014 vs. 46.7% for 2015-2019; p = 0.10). Findings were similar for Gram-negative infections (37% vs. 33.7%; p = 0.62), although more polymicrobial infections were detected (24.7% vs. 33.3%, respectively; p = 0.359). MDROs were involved in 15% of the cases, with an upward trend when comparing both periods (12.8% vs. 23.6%; p = 0.07). The most-used combination of local antibiotics-glycopeptide (vancomycin) plus aminoglycoside (gentamicin or tobramycin)-was met with low rates of resistance in the most frequently isolated microorganisms.

CONCLUSION

According to the results of the present study, rates of Gram-positive and Gram-negative infections remained consistent during the two study periods, but with an upward trend in MDRO and polymicrobial infections detected. The local combination of a glycopeptide plus an aminoglycoside was effective in treating the most frequently isolated microorganisms.

Metal-organic framework-based advanced therapeutic tools for antimicrobial applications

The escalating concern over conventional antibiotic resistance has emphasized the urgency in developing innovative antimicrobial agents. In recent times, metal-organic frameworks (MOFs) have garnered significant attention within the realm of antimicrobial research due to their multifaceted antimicrobial attributes, including the sustained release of intrinsic or exogenous antimicrobial components, chemodynamically catalyzed generation of reactive oxygen species (ROS), and formation of photogenerated ROS. This comprehensive review provides a thorough overview of the synthetic approaches employed in the production of MOF-based materials, elucidating their underlying antimicrobial mechanisms in depth. The focal point lies in elucidating the research advancements across various antimicrobial modalities, encompassing intrinsic component release system, extraneous component release system, auto-catalytical system, and energy conversion system. Additionally, the progress of MOF-based antimicrobial materials in addressing wound infections, osteomyelitis, and periodontitis is meticulously elucidated, culminating in a summary of the challenges and potential opportunities inherent within the realm of antimicrobial applications for MOF-based materials. STATEMENT OF SIGNIFICANCE: Growing concerns about conventional antibiotic resistance emphasized the need for alternative antimicrobial solutions. Metal-organic frameworks (MOFs) have gained significant attention in antimicrobial research due to their diverse attributes like sustained antimicrobial components release, catalytic generation of reactive oxygen species (ROS), and photogenerated ROS. This review covers MOF synthesis and their antimicrobial mechanisms. It explores advancements in intrinsic and extraneous component release, auto-catalysis, and energy conversion systems. The paper also discusses MOF-based materials' progress in addressing wound infections, osteomyelitis, and periodontitis, along with existing challenges and opportunities. Given the lack of related reviews, our findings hold promise for future MOF applications in antibacterial research, making it relevant to your journal's readership.

Necrotizing external otitis: diagnostic clues in the emergency department

PURPOSE

The assessment of necrotizing external otitis requires a high index of suspicion by the attending physician. The purpose of the study is to determine the accuracy of parameters available at the Emergency Department for the diagnosis of this pathology.

METHODS

Retrospective diagnostic accuracy study. Patients consulting at the Emergency Department for longstanding ear swelling, severe otalgia, and failure to respond to topical treatment were included. Otoscopy, physical examination, CT appearance, and analytical results were tested for the diagnosis of necrotizing external otitis, using nuclear imaging as gold standard. Sensitivity, specificity, likelihood ratios and ROC curves were calculated.

RESULTS

24 patients were included; 13 cases were necrotizing external otitis, and 11 cases were other external ear pathologies. Erythrocyte sedimentation rate and C-reactive protein levels were significantly associated with necrotizing external otitis (AUC 0.92 p < 0.001, and 0.8 p < 0.001). Positive likelihood ratios were 10.15 for values of erythrocyte sedimentation rate over 26 mm/h, and 8.25 for C-reactive protein levels over 10 mg/L. Negative likelihood ratios were 0.08 and 0.28, respectively. These results were significant. The rest of clinical and radiological parameters were less accurate.

CONCLUSIONS

Erythrocyte sedimentation rate and C-reactive protein are useful parameters in the evaluation of a case of longstanding otitis with clinical suspicion of necrotizing external otitis. If any of them is elevated, the probability of suffering this condition is significantly increased. If they are within normal ranges, an alternative diagnosis should be sought.

Progressive chronic calvarial osteomyelitis in rhino-orbital mucormycosis associated with COVID-19

We describe two cases of extensive indolent calvarial osteomyelitis after rhino-orbital-mucormycosis in diabetic patients previously diagnosed with COVID-19. Both patients presented with acute rhino-orbital symptoms about one month after being diagnosed with COVID-19. Treatment with intravenous liposomal Amphotericin B and prompt radical surgical debridement was instituted, but calvarial osteomyelitis ensued and persisted chronically despite maintenance of antifungal therapy and partial debridement of necrotic calvarial bone. The patients were discharged to continue antifungal therapy on a day-hospital regime. After more than 8 months of treatment, they remain with radiological signs of osteomyelitis but with no symptoms or intracranial extension of the infection. Calvarial indolent osteomyelitis secondary to mucormycosis is extremely rare, and little is known regarding its treatment. We believe it can be controlled with medical treatment and partial bony debridement although more studies are necessary to better define therapy.

Systemic lupus erythematosus Association between Osteomyelitis: A two-sample Mendelian randomization study in European population

Background

Systemic lupus erythematosus (SLE) has been correlated with osteomyelitis (OM), yet the underlying causal relationship remains poorly understood. This study aims to investigate the causal association between SLE and OM using Mendelian randomization (MR) analysis.

Methods

Genetic instrumental variables (IVs) correlated with SLE were extracted from a comprehensive genome-wide association study (GWAS) summary database (5201 cases and 9066 controls). OM was considered a SLE phenotype, and summary data from the fast GWA data portal were utilized for the analysis. Eligible IVs were extracted following rigorous quality control measures (P < 5 × 10-8, LD r2>0.001, distance 1 Mb, and F > 10). MR analysis was conducted using the Inverse Variance Weighted (IVW), MR-Egger, and Weighted Median (WM) methods after excluding potential confounders. Cochran's Q was applied for heterogeneity test. Pleiotropy was evaluated through MR-Egger intercept, MR-Pleiotropy Residual Sum and Outlier (MR-PRESSO) method, and Leave-one-SNP-out analysis.

Result

A total of 40 eligible IVs were included for MR analysis. IVW results demonstrated a positive causal association between SLE and OM (P = 0.049, OR = 1.167). Heterogeneity analysis reveal no significant heterogeneity in the IVW analysis (P = 0.5503). Pleiotropy tests, including MR-PRESSO global test and MR-Egger intercept, indicated no evidence of pleiotropy in our findings (P > 0.05). Additionally, the Leave-one-SNP-out analysis showed no substantial deviations when removing individual SNPs, thus supporting the robustness of our results.

Conclusion

This study establishes a genetic causal relationship between SLE and OM, indicating an increased risk of developing OM in individuals with SLE. Therefore, proactive management of SLE is advised to mitigate the risk of developing OM.

Monoclonal Antibody Disrupts Biofilm Structure and Restores Antibiotic Susceptibility in an Orthopedic Implant Infection Model

Bacterial biofilms on orthopedic implants are resistant to the host immune response and to traditional systemic antibiotics. Novel therapies are needed to improve patient outcomes. TRL1068 is a human monoclonal antibody (mAb) against a biofilm anchoring protein. For assessment of this agent in an orthopedic implant infection model, efficacy was measured by reduction in bacterial burden of Staphylococcus aureus, the most common pathogen for prosthetic joint infections (PJI). Systemic treatment with the biofilm disrupting mAb TRL1068 in conjunction with vancomycin eradicated S. aureus from steel pins implanted in the spine for 26 of 27 mice, significantly more than for vancomycin alone. The mechanism of action was elucidated by two microscopy studies. First, TRL1068 was localized to biofilm using a fluorescent antibody tag. Second, a qualitative effect on biofilm structure was observed using scanning electron microscopy (SEM) to examine steel pins that had been treated in vivo. SEM images of implants retrieved from control mice showed abundant three-dimensional biofilms, whereas those from mice treated with TRL1068 did not. Clinical Significance: TRL1068 binds at high affinity to S. aureus biofilms, thereby disrupting the three-dimensional structure and significantly reducing implant CFUs in a well-characterized orthopedic model for which prior tested agents have shown only partial efficacy. TRL1068 represents a promising systemic treatment for orthopedic implant infection.

Predictive Value of Radiographic and Magnetic Resonance Imaging Characteristics on Patient Outcomes in Confirmed Acute Osteomyelitis of the Extremities

OBJECTIVE

The aim of this study was to determine whether imaging characteristics on plain radiography, magnetic resonance imaging (MRI), and diffusion-weighted imaging are predictive of patient outcomes in cases of confirmed osteomyelitis (OM).

MATERIALS AND METHODS

In this cross-sectional study, 3 experienced musculoskeletal radiologists evaluated pathologically proven cases of acute extremity OM and recorded imaging characteristics on plain radiographs, MRI, and diffusion-weighted imaging. These characteristics were then compared with the patient outcomes after a 3-year follow-up using length of stay, amputation-free survival, readmission-free survival, and overall survival using multivariate Cox regression analysis. Hazard ratio and corresponding 95% confidence intervals are reported. False discovery rate-adjusted P values were reported.

RESULTS

For the 75 consecutive cases of OM in this study, multivariate Cox regression analysis adjusting for sex, race, age, body mass index, erythrocyte sedimentation rate, C-reactive protein, and white blood cell count showed no correlation among any of the recorded characteristics on imaging and patient outcomes. Despite the high sensitivity and specificity of MRI for diagnosing OM, there was no correlation between MRI characteristics and patient outcomes. Furthermore, patients with coexistent abscess of the soft tissue or bone with OM had comparable outcomes using the previously mentioned metrics of length of stay, amputation-free survival, readmission-free survival, and overall survival.

CONCLUSION

Neither radiography nor MRI features predict patient outcomes in extremity OM.

Mid-Term Results of Single-Stage Surgery for Patients with Chronic Osteomyelitis Using Antibiotic-Loaded Resorbable PerOssal® Beads

This retrospective study reports on the treatment of chronic osteomyelitis with local debridement combined with PerOssal^®. The diagnosis of chronic osteomyelitis was confirmed in all cases and classified according to the Cierny-Mader (C-M) classification. The primary outcome was the eradication of infection at a minimum of one year after surgery. A total of 93 patients (median age: 40 years) were included. The most represented sites were the femur (24, 25.8%) and tibia (52, 55.9%). Twenty-six patients (28.0%) had significant local or systemic comorbidities (C-M Class B hosts). According to anatomic type, 31 cases were type I, 13 type II, 21 type III and 28 type IV. Vancomycin was added to PerOssal^® in most cases (80, 86.0%). In 24 (25.8%) cases, Vancomycin and Rifampicin were combined. In 32 (34.4%) cases, intraoperative cultures were negative. Staphylococcus aureus was isolated in 39 (63.9%) patients, and Gram-negative bacteria were isolated in 12 cases. The median follow-up was 21 months (range 12-84). A total of 21 (22.6%) patients developed an infection recurrence (IR) after a median follow-up of 11 months (range: 1-47). PerOssal^® holds several practical advantages compared to other bone void fillers. Thus, due to its good biocompatibility and sufficient antibiotic release, it represents a viable adjuvant treatment in chronic osteomyelitis.

The ubiquitination of RIPK2 is mediated by Peli3 and negatively regulates the onset of infectious osteomyelitis

Osteomyelitis is the infection and destruction of bone. Until now, there is no universal protocol for its treatment. Receptor-interacting serine/threonine-protein kinase 2 (RIPK2) was implicated in the development of osteomyelitis. However, its detailed mechanism remains unknown. 6-8 weeks old wild-type or Pellino E3 Ubiquitin Protein Ligase Family Member 3 (Peli3) deficiency mice were injected with S. aureus to induce osteomyelitis. RAW264.7 cells or bone marrow-derived macrophages (BMDMs) isolated from mice, were treated with lipopolysaccharides (LPS). Knocking down Peli3 in RAW264.7 cells increased the expressions of inflammatory cytokines after the stimulation of LPS, including interleukin-1β, interleukin-6 and tumor necrosis factor-α. Inflammation was also activated in S. aureus-induced Peli3 deficiency mice. Moreover, Peli3 deficiency mice also displayed more severe symptoms of osteomyelitis in S. aureus-infected mice. Moreover, Peli3 targeted and degraded RIPK2 through K48-linked ubiquitination. Peli3 negatively modulates osteomyelitis by degrading RIPK2. Our data further expand current understanding of RIPK2 on osteomyelitis, which suggests that RIPK2 might serve as novel therapeutic target for treating osteomyelitis.

Solitary bone plasmacytoma of the tibia presenting as chronic osteomyelitis: A rare case report and literature review

RATIONALE

Plasmacytoma is a rare plasma cell dyscrasia that grows within the axial skeleton or soft tissue structures as solitary or multiple masses. The primary types are solitary plasmacytoma, including solitary bone plasmacytoma (SBP) and solitary extramedullary plasmacytoma, and multiple solitary plasmacytomas. SBP is characterized by localized proliferation of monoclonal plasma cells and is rare. However, SBP with chronic osteomyelitis is even rarer.

PATIENT CONCERNS

A 47-year-old man previously diagnosed with chronic osteomyelitis presented with repeated discharge and ulceration in the front of his right tibia.

DIAGNOSIS, INTERVENTIONS AND OUTCOMES

Lower extremity magnetic resonance imaging (MRI) and computed tomography (CT) examinations showed dead bone formation and surrounding inflammatory edema. Thus, the patient underwent dead bone excision and fenestration of the bone marrow cavity. The histopathologic examination results indicated plasmacytoma. Therefore, we administered radiotherapy with satisfactory results.

LESSONS

Physicians should pay close attention to chronic osteomyelitis because it may be accompanied by plasmacytoma. Postoperative pathological and immunohistochemical examinations are crucial, and surgical resection of the lesion and local radiotherapy are effective treatment methods.

A Rare Case of Carpal Osteomyelitis in a Spinal Cord Injury Patient: A Case Report

Osteomyelitis of the carpal bones is rare and usually occurs in the setting of penetrating trauma. Here, to our knowledge, we report the first known documented case of carpal osteomyelitis in a spinal cord injury (SCI) patient and discuss the medical management of this patient. A 62-year-old male with a remote history of traumatic SCI at T5 American Spinal Injury Association (ASIA) Impairment Scale (AIS) A and a history of IV polysubstance abuse presented to an acute care hospital for acute non-traumatic right dorsal wrist pain. Initial hand and wrist X-rays were negative for acute findings. After eight weeks of continued symptoms, severely impaired activities of daily living, and decreased independence, the patient was admitted to acute rehabilitation. MRI showed bone edema changes involving the distal radius, scaphoid, lunate, majority of the capitate, and hamate, concerning possible osteomyelitis. A CT-guided biopsy of the scaphoid confirmed methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis. He completed a seven-day course of IV vancomycin followed by 12 weeks of oral doxycycline. A follow-up positron emission tomography (PET) scan showed no evidence of osteomyelitis, and the patient returned to a baseline functional status of modified independence for most activities of daily living. Carpal osteomyelitis in SCI patients is rare and can be challenging to diagnose, given that it can present with a lack of systemic symptoms and nonspecific laboratory markers. This is the first documented case of carpal osteomyelitis involving an SCI individual. The continuation of diminishing hand mobility, function, and independence should prompt further workup with MRI to rule out uncommon but potentially debilitating diseases such as osteomyelitis.

Diagnosis and treatment of chronic osteomyelitis based on nanomaterials

Chronic osteomyelitis is a painful and serious disease caused by infected surgical prostheses or infected fractures. Traditional treatment includes surgical debridement followed by prolonged systemic antibiotics. However, excessive antibiotic use has been inducing rapid emergence of antibiotic-resistant bacteria worldwide. Additionally, it is difficult for antibiotics to penetrate internal sites of infection such as bone, thus limiting their efficacy. New approaches to treat chronic osteomyelitis remain a major challenge for orthopedic surgeons. Luckily, the development of nanotechnology has brought new antimicrobial options with high specificity to infection sites, offering a possible way to address these challenges. Substantial progress has been made in constructing antibacterial nanomaterials for treatment of chronic osteomyelitis. Here, we review some current strategies for treatment of chronic osteomyelitis and their underlying mechanisms.

Existing and Novel Biomaterials for Bone Tissue Engineering

The treatment of bone defects remains one of the major challenges in modern clinical practice. Nowadays, with the increased incidence of bone disease in an aging population, the demand for materials to repair bone defects continues to grow. Recent advances in the development of biomaterials offer new possibilities for exploring modern bone tissue engineering strategies. Both natural and synthetic biomaterials have been used for tissue repair. A variety of porous structures that promote cell adhesion, differentiation, and proliferation enable better implant integration with increasingly better physical properties. The selection of a suitable biomaterial on which the patient's new tissue will grow is one of the key issues when designing a modern tissue scaffold and planning the entire treatment process. The purpose of this article is to present a comprehensive literature review of existing and novel biomaterials used in the surgical treatment of bone tissue defects. The materials described are divided into three groups-organic, inorganic, and synthetic polymers-taking into account current trends. This review highlights different types of existing and novel natural and synthetic materials used in bone tissue engineering and their advantages and disadvantages for bone defects regeneration.

Risk factors of transport gap bending deformity in the treatment of critical-size bone defect after bone transport

Background

The purpose of this study was to investigate the risk factors of transport gap bending deformity (TGBD) in the treatment of critical-size bone defect (CSBD) after the removal of the external fixator.

Methods

From January 2008 to December 2019, 178 patients with bone defects of the lower extremity caused by infection were treated by bone transport using a unilateral external fixator in our medical institution. TGBD was defined as the bone callus in the distraction area with a deviation to the force line of the femur (> 10°) or tibia (> 12°) after removal of the external fixator. The Association for the Study and Application of the Method of Ilizarov (ASAMI) standard was applied to assess the bone and functional outcomes. After the data were significant by the T-test or Pearson’s Chi-square test was analyzed, odds ratios were calculated using logistic regression tests to describe factors associated with the diagnosis of TGBD.

Results

A total of 178 patients were enrolled in the study, with a mean follow-up time of 28.6 ± 3.82 months. The positive result of the bacteria isolated test was observed in 144 cases (80.9%). The rate of excellent and good in the bone outcomes (excellent/good/fair/poor/failure, 41/108/15/14/0) was 83.7%, and 92.3% in the functional results (excellent/good/fair/poor/failure, 50/98/16/14/0) according to the ASAMI criteria. TGBD after removal of external fixator occurred in twenty-two patients (12.3%), including 6 tibias, and 16 femurs. Age > 45 years, BMI > 25 kg/m², femoral defect, diabetes, osteoporosis, glucocorticoid intake, duration of infection > 24 months, EFT > 9 months, EFI > 1.8 month/cm were associated significantly with a higher incidence of TGBD in the binary logistic regression analysis (P < 0.05). The incidence more than 50% was found in patients with femoral defect (76.1%), osteoporosis (72.7%), BMI > 25 kg/m² (69.0%), diabetes (59.5%), glucocorticoid intake (54.7%). In the multivariate logistic regression analyses, the following factors were associated independently with TGBD, including age > 45 years, BMI > 25 kg/m², femoral defect, diabetes, and osteoporosis.

Conclusions

Bone transport using a unilateral external fixator was a safe and practical method in the treatment of CSBD caused by infection. The top five risk factors of TGBD included femoral defect, BMI > 25 kg/m², duration of bone infection > 24 months, age > 45 years, and diabetes. Age > 45 years, BMI > 25 kg/m², femoral defect, osteoporosis, and diabetes were the independent risk factors. The higher incidence of TGBD may be associated with more risk factors.

Diagnosis and Treatment Modalities for Osteomyelitis

Osteomyelitis is an infection-related inflammatory disease of the bones. Imaging and laboratory results are typically used to support a clinical diagnosis of osteomyelitis. Microbial cultures and bone biopsies provide conclusive diagnoses. The first imaging procedure that needs to be done is radiography, but its sensitivity is low in the early stages of the disease. The sensitivity of magnetic resonance imaging, both with and without contrast material, is higher for detecting areas of bone necrosis in advanced stages. Patients can be categorised for surgical treatment using a staging system based on major and minor risk factors. The main course of treatment should be antibiotics, which should be chosen depending on the findings of the culture and the characteristics of each patient. Bony debridement surgery is frequently required, and in high-risk patients or those with severe illness, additional surgical intervention can be necessary. Better outcomes are being attained in the treatment of this illness thanks to advancements in surgical treatment, antibiotic therapy, and the current resources for precise diagnosis and tailored responses to each kind of osteomyelitis. The classification systems that are most frequently employed, as well as the general epidemiological ideas, are presented together with the discussion of acute and chronic osteomyelitis. The key recommendations for diagnosing infections clinically, in the laboratory, and through imaging are covered, along with the recommendations for surgical and antibiotic procedures, and the function of hyperbaric oxygen as adjuvant therapy. We evaluate the osteomyelitis-related articles, summarise the most recent developments in diagnostic procedures and therapeutic regimens, evaluate the benefits and drawbacks of various diagnostic modalities and therapeutic approaches, and suggest areas of focus to help current diagnostic and therapeutic approaches.

Thermosensitive vancomycin@PLGA-PEG-PLGA/HA hydrogel as an all-in-one treatment for osteomyelitis

Osteomyelitis is a difficult-to-treat infectious disease. Treatment, which includes controlling the infection and removing necrotic tissues, is challenging. Considering the side effects and drug resistance of systemic antibiotics, local drug delivery systems are being explored. Antibiotic-loaded bone cement is the main treatment strategy; however, it has several disadvantages. Thus, based on its thermosensitive gelation properties, poly(D, L-lactide-co-glycolide)-poly(ethylene glycol)-poly(D, L-lactide-co-glycolide) (PLGA-PEG-PLGA) copolymer was used as a sustained-release drug carrier by calibrating its synthesis parameters. We prepared and characterized vancomycin@PLGA-PEG-PLGA/hydroxyapatite (HA) thermosensitive hydrogel with an LA/GA ratio of 15:1. The rheological characteristics, sol-gel phase-transition properties, and critical micelle concentration value of the PLGA-PEG-PLGA/HA complex confirmed that it undergoes a temperature-sensitive sol-gel phase transition. Furthermore, the HA in the composite increased the storage modulus of the system. FT-IR, XRD, and TEM findings showed that HA could be dispersed uniformly in the PLGA-PEG-PLGA polymer. Moreover, HA neutralized acidity during polymer degradation, improving in vitro cytocompatibility. In vitro and in vivo antibacterial experiments showed that the composite sustained-release system exhibited good bone repair characteristics owing to its efficacy in infection treatment. Therefore, vancomycin@PLGA-PEG-PLGA/HA allows sustained release of antibiotics and promotes bone tissue repair, showing potential for wide clinical applicability.

Bone Involvement in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by a wide variability of clinical manifestations due to the potential involvement of several tissues and internal organs, with a relapsing and remitting course. Dysregulation of innate and adaptive immune systems, due to genetic, hormonal and environmental factors, may be responsible for a broad spectrum of clinical manifestations, affecting quality of life, morbidity and mortality. Bone involvement represents one of the most common cause of morbidity and disability in SLE. Particularly, an increased incidence of osteoporosis, avascular necrosis of bone and osteomyelitis has been observed in SLE patients compared to the general population. Moreover, due to the improvement in diagnosis and therapy, the survival of SLE patient has improved, increasing long-term morbidities, including osteoporosis and related fractures. This review aims to highlight bone manifestations in SLE patients, deepening underlying etiopathogenetic mechanisms, diagnostic tools and available treatment.

Acute shortening and re-lengthening versus antibiotic calcium sulfate-loaded bone transport for the management of large segmental tibial defects after trauma

Background

The purpose of this paper was to compare the clinical effects of acute shortening and re-lengthening (ASR) technique with antibiotic calcium sulfate-loaded bone transport (ACSBT) technique for the management of large segmental tibial defects after trauma.

Methods

In this retrospective study, 68 patients with large segmental tibial defects were included and completely followed. The bone loss was 3–10 cm. ASR group included 32 patients, while ACSBT group contained 36. There was no significant difference in demographic information between the two groups. The external fixation time (EFT) and external fixation index (EFI) were compared. Bone defect healing and limb functions were evaluated according to the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria. Complications were compared by Paley classification.

Results

The mean EFT was 9.2 ± 1.8 months in ASR group and 10.1 ± 2.0 months in ACSBT group, respectively. The mean EFI was 1.5 ± 0.2 month/cm and 1.4 ± 0.3 month/cm. According to the ASAMI criteria, in ASR group bone defect healing was excellent in 22 cases, good in 7 cases and fair in 3 cases. In ACSBT group, it was excellent in 23 cases, good in 11 cases and fair in 2 cases. In ASR group, the limb function was excellent in 15 cases, good in 7 cases and fair in 10 cases, while it was excellent in 14 cases, good in 9 cases and fair in 13 cases with ACSBT group. There was no significant difference in EFI, bone defect healing and limb functions between the two groups (p > 0.05). The mean number of complications per patient in ACSBT group was significantly lower than that in ASR group (p < 0.05).

Conclusion

Both techniques can be successfully used for the management of large segmental tibial defects after trauma. There was no significant difference in EFI, limb functions and bone defect healing between the two groups. Compared with ASR group, the complication incidence in ACSBT group was lower, especially the infection-related complications. Therefore, for patients with large segmental bone defects caused by infection or osteomyelitis, ACSBT technique could be the first choice.

Establishment of a reliable in-vivo model of implant-associated infection to investigate innovative treatment options

The increasing number of implant-associated infections and of multiresistant pathogens is a major problem in the daily routine. In the field of osteomyelitis, it is difficult to manage a valid clinical study because of multiple influencing factors. Therefore, models of osteomyelitis with a simulation of the pathophysiology to evaluate treatment options for implant-associated infections are necessary. The aim of this study is to develop a standardized and reproducible osteomyelitis model in-vivo to improve treatment options. This study analyses the influence of a post-infectious implant exchange one week after infection and the infection progress afterward in combination with a systemic versus a local antibiotic treatment in-vivo. Therefore, the implant exchange, the exchange to a local drug-delivery system with gentamicin, and the implant removal are examined. Furthermore, the influence of an additional systemic antibiotic therapy is evaluated. An in-vivo model concerning the implant exchange is established that analyzes clinic, radiologic, microbiologic, histologic, and immunohistochemical diagnostics to obtain detailed evaluation and clinical reproducibility. Our study shows a clear advantage of the combined local and systemic antibiotic treatment in contrast to the implant removal and to a non-combined antibiotic therapy. Group genta/syst. showed the lowest infection rate with a percentage of 62.5% concerning microbiologic analysis, which is in accordance with the immunohistochemical, cytochemical, histologic, and radiologic analysis. Our in-vivo rat model has shown valid and reproducible results, which will lead to further investigations regarding treatment options and influencing factors concerning the therapy of osteomyelitis and implant-associated infections.

Marein Prevented LPS-Induced Osteoclastogenesis by Regulating the NF-κB Pathway In Vitro

Many bone diseases such as osteolysis, osteomyelitis, and septic arthritis are caused by gram-negative bacterial infection, and lipopolysaccharide (LPS), a bacterial product, plays an essential role in this process. Drugs that inhibit LPS-induced osteoclastogenesis are urgently needed to prevent bone destruction in infective bone diseases. Marein, a major bioactive compound of Coreopsis tinctoria, possesses anti-oxidative, anti-inflammatory, anti-hypertensive, anti-hyperlipidemic, and anti-diabetic effects. In this study, we measured the effect of marein on RAW264.7 cells by CCK-8 assay and used TRAP staining to determine osteoclastogenesis. The levels of osteoclast-related genes and NF-κB-related proteins were then analyzed by western blot, and the levels of pro-inflammatory cytokines were quantified by ELISA. Our results showed that marein inhibited LPS-induced osteoclast formation by osteoclast precursor RAW264.7 cells. The effect of marein was related to its inhibitory function on expressions of pro-inflammatory cytokines and osteoclast-related genes containing RANK, TRAF6, MMP-9, CK, and CAII. Additionally, marein leads to markedly inhibited NF-κB signaling pathway activation in LPS-induced RAW264.7 cells. Concurrently, when the NF-κB signaling pathway was inhibited, osteoclast formation and pro-inflammatory cytokine expression were decreased. Collectively, marein could inhibit LPS-induced osteoclast formation in RAW264.7 cells via regulating the NF-κB signaling pathway. Our data demonstrate that marein might be a potential drug for bacteria-induced bone destruction disease. Our findings provide new insights into LPS-induced bone disease.

Antibiotic-loaded calcium sulfate in clinical treatment of chronic osteomyelitis: a systematic review and meta-analysis

Background

Present work was aimed to gather accessible evidence on the eradication rates and related postoperative complications of antibiotic-loaded calcium sulfate (CS) as an implant in the treatment of chronic osteomyelitis (COM).

Methods

Databases including PubMed, EMBASE, Medline, Ovid and Cochrane library were searched from their dates of initiation until November 2021. Two independent authors scrutinized the relevant studies based on the effectiveness of radical debridement combined with antibiotic-loaded CS for COM; data extraction and quality assessment of the Methodological Index for Non-Randomized Studies (MINORS) criteria were also performed by the authors. In addition, clinical efficacy mainly depended on the evaluation of eradication rates and complications, and all the extracted data are pooled and analyzed by STATA 16.0.

Results

A total of 16 studies with 917 patients (920 locations) were recruited, with an overall eradication rate of 92%. Moreover, the overall reoperation rate, overall refracture rate, overall delayed wound healing rate, and the rate of aseptic wound leakage were 9.0%, 2.0%, 20.0%, and 12.0%, respectively. Moreover, the choice of tobramycin-loaded CS or vancomycin combined with gentamicin-loaded CS did not affect the eradication rate, and the incidence of postoperative complications in COM patients (all $$P>0.05$$ P > 0.05 ). The general quality of the included studies was fair.

Conclusions

Our meta-analysis indicated that the overall eradication rate of COM treated with antibiotic-loaded CS was 92%. Delayed healing is the most common postoperative complication. The choice of tobramycin-loaded CS or vancomycin combined with gentamicin-loaded CS did not affect the eradication rate and the incidence of postoperative complications in COM patients.

Bioengineered Living Bone Grafts-A Concise Review on Bioreactors and Production Techniques In Vitro

It has been observed that bone fractures carry a risk of high mortality and morbidity. The deployment of a proper bone healing method is essential to achieve the desired success. Over the years, bone tissue engineering (BTE) has appeared to be a very promising approach aimed at restoring bone defects. The main role of the BTE is to apply new, efficient, and functional bone regeneration therapy via a combination of bone scaffolds with cells and/or healing promotive factors (e.g., growth factors and bioactive agents). The modern approach involves also the production of living bone grafts in vitro by long-term culture of cell-seeded biomaterials, often with the use of bioreactors. This review presents the most recent findings concerning biomaterials, cells, and techniques used for the production of living bone grafts under in vitro conditions. Particular attention has been given to features of known bioreactor systems currently used in BTE: perfusion bioreactors, rotating bioreactors, and spinner flask bioreactors. Although bioreactor systems are still characterized by some limitations, they are excellent platforms to form bioengineered living bone grafts in vitro for bone fracture regeneration. Moreover, the review article also describes the types of biomaterials and sources of cells that can be used in BTE as well as the role of three-dimensional bioprinting and pulsed electromagnetic fields in both bone healing and BTE.

Addressing common orthopaedic calamities with microsurgical solutions

Reconstructive microsurgery has been an essential aspect of orthopaedic surgery and extremity reconstruction since the introduction of the operating microscope in the mid-20^th century. The reconstructive ladder ranges from simple healing by secondary intention to complex procedures such as free tissue transfer and vascularized composite allotransplantation. As orthopaedic surgery has evolved over the past 60 years, so too have the reconstructive microsurgical skills that are often needed to address common orthopaedic surgery problems. In this article, we will discuss a variety of complex orthopaedic surgery scenarios ranging from trauma to infection to tumor resection as well as the spectrum of microsurgical solutions that can aid in their management.

Management of chronic osteomyelitis of the femur and tibia: a scoping review

Osteomyelitis refers to an inflammatory process causing bone destruction and necrosis. Managing such a persistent disease is complex, with a number of authors reporting different techniques. This scoping review aims to map and summarize the literature on treatment of chronic femoral and tibial osteomyelitis, in order to improve the reader's understanding of potential treatments and identify areas of further research.The methodological framework of the Joanna Briggs Institute was followed. A computer-based search was conducted in PubMed, EMBASE, MEDLINE, EMCARE and CINAHL, for articles reporting treatment of chronic tibial/femoral osteomyelitis. Two reviewers independently performed title/abstract and full-text screening according to pre-defined criteria.A total of 1230 articles were identified, with 40 finally included. A range of treatments are reported, with the core principles being removal of infected tissue, dead-space management and antibiotic therapy. The majority (84.5%) of patients presented with stage III or IV disease according to the Cierny-Mader classification, and Staphylococcus aureus was the most commonly isolated organism. The proportion of patients achieving remission with no recurrence during follow-up varies from 67.7-100.0%.The majority of studies report excellent outcomes in terms of infection remission and lack of recurrence. However, identifying specific patient or treatment-related factors which may affect outcomes is currently challenging due to the nature of the included studies and unclear reporting of treatment outcomes. It is now important to address this issue and identify such factors using further high-level research methods such as randomized controlled trials and comparative cohort studies. Cite this article: EFORT Open Rev 2021;6:704-715. DOI: 10.1302/2058-5241.6.200136.

Advances in pharmacotherapy for diabetic foot osteomyelitis

Introduction: The diagnosis of diabetic foot osteomyelitis (DFO) is usually clinical. Its severity is related to the location and depth of the lesion, and the presence of necrosis or gangrene. The aetiology of diabetic foot osteomyelitis (DFO) is usually polymicrobial, and DFO is often associated with chronic or recurring ulceration.Areas covered: We built on the  International Working Group on the Diabetic Foot (IWGDF) guidelines on the management of diabetic foot infection, providing an outline of the current and new concepts in pharmacotherapy in DFO. We assess future strategies in both medical, surgical and combination management of DFO.Expert opinion: Surgical removal of infected bone is considered as the standard treatment, but a medical approach of certain selected situations has now proven efficacy in selected patients. The combination of new modalities in local antibiotic delivery may provide better long-term solutions and more lasting remission and avoid the disadvantages of prolonged systemic antibiotics.

Sensitive and Label-free Detection of Bacteria in Osteomyelitis through Exo III-Assisted Cascade Signal Amplification

Rapid and sensitive pathogenic bacterial identification and isolation from complicated clinical specimens are of great importance for the early diagnosis and prevention of osteomyelitis. Herein, we proposed a novel methicillin-resistant Staphylococcus aureus (MRSA) detection strategy through two specially designed streptavidin magnetic bead-based probes, including a capture probe and a report probe. In detail, the capture probe takes the responsibility to specially bind with the surface protein of MRSA and leads to the liberation of the promoter which could subsequently initiate report probe-based signal amplification. Afterward, the hybridization of the promoter probe with the report probe could then transform the protruding 3' terminus of template DNA in the report probe into a blunt end. With the assistance of Exo III, the template could be digested to liberate the promoter to form a recycle and to liberate the biprobe to induce the following rolling circle amplification (RCA)-based signal amplification. Through the integration of the Exo III-assisted recycle and RCA-based signal amplification, the proposed method exhibited a favorable detection performance.

Osteomyelitis of the jaws in patients with pycnodysostosis: a systematic review

Introduction

Pycnodysostosis is a rare autosomal recessive syndrome that provides the abnormal bone metabolism that increases the susceptibility of patients to develop osteomyelitis.

Objective

This systematic review was conducted to analyze the risk factors associated with the development of complications in the jaws (fractures and osteomyelitis), as well as their clinical-pathological characteristics and therapeutic approaches in patients with pycnodysostosis.

Methods

Searches were performed in the PubMed, Web of Science, Scopus, Lilacs, and Cochrane databases. Case reports or case series that met the eligibility criteria according to the PRISMA statement were included. The full texts of 31 articles were retrieved. Twenty of these articles published between 1969 and 2018 were selected, which described 26 cases of osteomyelitis in patients with pycnodysostosis.

Results

The mean age of the patients was 37.84 years; the male-to-female was 1.36:1. The mandible was the most affected site (76.9%). Tooth extraction was the main risk factor for osteomyelitis (61.5%), followed by infection (26.8%) and mandibular fracture (23.0%). Antibiotic therapy alone or combined with some surgical procedure was the treatment used in most cases (80.7%).

Conclusion

The findings of this review showed that patients with pycnodysostosis are more likely to develop osteomyelitis of the jaws after surgical procedures, especially tooth extraction which remains the main risk factor for its establishment. In addition, prophylactic antibiotic-therapy in the pre- and postoperative periods may prevent the development of osteomyelitis in pycnodysostosis.

Management of Polymicrobial Cierny-Mader Grade 3 and 4 Chronic Osteomyelitis of the Femur

Introduction

Osteomyelitis refers to an inflammatory process affecting the bone and bone marrow. Chronic disease occurs following the formation of a necrotic, devascularised sequestrum. Regardless of the approach, treatment is complex and resource-intensive, often requiring multiple surgical interventions and extended antibiotic therapy. This study aims to review the treatment of chronic osteomyelitis of the femur by a single surgeon over seven years (January 2013 to January 2020).

Materials and methods

We retrospectively reviewed a consecutive series of 14 patients. Data collected includes age, sex, medical history, treatment, pathogen, C-reactive protein levels, outcome, and follow-up period. The EuroQOL five-dimensional questionnaire (EQ-5D-5L) and Visual Analogue Scale (EQ-VAS) were used to assess health outcomes. Data concerning total treatment costs and reimbursement received was also collected.

Results

Although 10/14 (71.4%) patients were considered in remission at final follow-up, only six (42.9%) achieved remission and showed no recurrence after initial treatment. The mean total treatment cost was £39,249.50, with a mean deficit of - £19,080.10 when considering reimbursement. Patients showed a significantly lower mean EQ-5D score (0.360) compared to the national population mean of 0.856 (P = .0018) as well as a lower mean EQ-VAS (61.7) compared to the population norm of 82.8 (P = .013). 

Conclusion

The extensive nature of the infection, high rates of co-morbidity, and the growth of more than a single pathogen may explain the lower success rate observed. In these patients, recurrence may be highly likely and thus regular follow-up is vital in order to ensure effective management.

Impact of Zika virus on the human type I interferon osteoimmune response

BACKGROUND

The developing field of osteoimmunology supports importance of an interferon (IFN) response pathway in osteoblasts. Clarifying osteoblast-IFN interactions is important because IFN is used as salvage anti-tumor therapy but systemic toxicity is high with variable clinical results. In addition, osteoblast response to systemic bursts and disruptions of IFN pathways induced by viral infection may influence bone remodeling. ZIKA virus (ZIKV) infection impacts bone development in humans and IFN response in vitro. Consistently, initial evidence of permissivity to ZIKV has been reported in human osteoblasts.

HYPOTHESIS

Osteoblast-like Saos-2 cells are permissive to ZIKV and responsive to IFN.

METHODS

Multiple approaches were used to assess whether Saos-2 cells are permissive to ZIKV infection and exhibit IFN-mediated ZIKV suppression. Proteomic methods were used to evaluate impact of ZIKV and IFN on Saos-2 cells.

RESULTS

Evidence is presented confirming Saos-2 cells are permissive to ZIKV and support IFN-mediated suppression of ZIKV. ZIKV and IFN differentially impact the Saos-2 proteome, exemplified by HELZ2 protein which is upregulated by IFN but non responsive to ZIKV. Both ZIKV and IFN suppress proteins associated with microcephaly/pseudo-TORCH syndrome (BI1, KI20A and UBP18), and ZIKV induces potential entry factor PLVAP.

CONCLUSIONS

Transient ZIKV infection influences osteoimmune state, and IFN and ZIKV activate distinct proteomes in Saos-2 cells, which could inform therapeutic, engineered, disruptions.

MRI nomenclature for musculoskeletal infection

The Society of Skeletal Radiology (SSR) Practice Guidelines and Technical Standards Committee identified musculoskeletal infection as a White Paper topic, and selected a Committee, tasked with developing a consensus on nomenclature for MRI of musculoskeletal infection outside the spine. The objective of the White Paper was to critically assess the literature and propose standardized terminology for imaging findings of infection on MRI, in order to improve both communication with clinical colleagues and patient care.A definition was proposed for each term; debate followed, and the committee reached consensus. Potential controversies were raised, with formulated recommendations. The committee arrived at consensus definitions for cellulitis, soft tissue abscess, and necrotizing infection, while discouraging the nonspecific term phlegmon. For bone infection, the term osteitis is not useful; the panel recommends using terms that describe the likelihood of osteomyelitis in cases where definitive signal changes are lacking. The work was presented virtually to SSR members, who had the opportunity for review and modification prior to submission for publication.

Physiologically Based Population Pharmacokinetic Modeling Approach for Ciprofloxacin in Bone of Patients Undergoing Orthopedic Surgery

Ciprofloxacin is highly active against bacteria that commonly cause bone infections. However, the time-course of ciprofloxacin in bone has not been characterized using population pharmacokinetic modeling. Thirty-nine patients received a 1-h infusion of 400 mg of ciprofloxacin before orthopedic surgery. Blood and bone samples were collected at 0.5 to 20 h following the start of the infusion. Bone samples were separated into cortical and cancellous bone and pulverized under liquid nitrogen using a cryogenic mill. Ciprofloxacin in plasma, and cortical and cancellous bone was quantified by liquid chromatography-tandem mass spectrometry. A physiologically based pharmacokinetic modeling approach was utilized to describe the concentration-time profiles in plasma and bone. Ciprofloxacin concentrations ranged from 0.176 to 5.98 mg/L (median, 1.67; density, 1.99 g/cm³) in cortical, and 0.224 to 14.6 mg/L (median, 1.22; 1.92 g/cm³) in cancellous bone. The average observed cortical bone/plasma concentration ratio was 0.67 at 0.5 to 2 h (n = 7) and 5.1 at 13 to 20 h (n = 9). For cancellous bone the respective average ratios were 0.77 and 4.4. The population PK model included a central (blood) compartment, two peripheral tissue compartments, and compartments for the organic and inorganic (hydroxyapatite) matrix in cortical and cancellous bone. The population mean ciprofloxacin clearance was 20.7 L/h. The estimated partition coefficients of the organic bone matrix were 3.39 for cortical and 5.11 for cancellous bone. Ciprofloxacin achieved higher concentrations in bone than plasma. Slow redistribution from bone to plasma may have been due to binding to the inorganic bone matrix. The developed model presents a step toward optimized antibiotic dosing in osteomyelitis.

Tigecycline Versus Colistin in the Treatment of Carbapenem-resistant Acinetobacter baumannii Complex Osteomyelitis

Background: Acinetobacter baumannii complex is an increasingly important cause of osteomyelitis. It is considered a difficult to treat agent, due to increasing antimicrobial resistance and few available therapeutic options. Objective: To compare effectiveness and tolerability of tigecycline and colistin in patients with osteomyelitis caused by carbapenem-resistant A. baumannii complex (CRABC). Methods: This retrospective review included all patients admitted to a 150-bed tertiary hospital from 2007 to 2015 with microbiologically confirmed CRABC osteomyelitis for which they received tigecycline or colistin. Data on demographic and clinical characteristics, adverse events, and outcomes 12 months after the end of antimicrobial treatment were analysed and stratified according to the antimicrobial used. Results: 65 patients were included, 34 treated with colistin and 31 with tigecycline. There were significantly more men (P = 0.028) in the colistin group, and more smokers (P = 0.021) and greater occurrence of chronic osteomyelitis (P = 0.036) in the tigecycline treatment group. Median duration of therapy was 42.5 days for colistin and 42 days for tigecycline, with no significant difference. Overall incidence of adverse events was higher in the colistin group (P = 0.047). In particular, incidence of renal impairment was also higher in this group (P = 0.003). Nausea and vomiting were more frequent with tigecycline (P = 0.046). There were no significant differences between groups in relapse, amputation, or death. Conclusions: Tigecycline had a better safety profile than colistin in the treatment of osteomyelitis due to CRABC, with no significant difference in outcomes after 12 months of follow-up.

Extirpative Cultures Reveal Infectious Pubic Bone Osteomyelitis in Prostate Cancer Survivors With Urinary-Pubic Symphysis Fistulae (UPF)

OBJECTIVE

To examine the infectious features of patients with urinary pubic symphysis fistula (UPF) and their association with osteomyelitis.

METHODS

We conducted a review of our quality improvement database for 36 patients with UPF undergoing bone resection and extirpative surgery from October 2012 to January 2019. An assessment of bone and urine cultures was carried out along with surgical, radiologic, and demographic data. We analyzed descriptive statistics and used Fisher Exact Tests and unpaired Welch t tests to assess for associations with positive bone cultures.

RESULTS

In our cohort, 33 patients (91.7%) had positive bone cultures with the 3 most common organisms being candida (22.0%), enterococcus (18.0%), and pseudomonas (10.0%). There was a correlation between positive preoperative urine culture and positive bone culture (P <.01), with 63.0% of those with positive urine cultures growing the same organism on bone culture.

CONCLUSION

In this series, 91.7% of patients undergoing extirpative surgery for UPF at our institution have positive bone cultures at time of pubic bone debridement. Additionally, we demonstrate a statistically significant correlation between positive urine cultures and positive bone cultures in these patients. This supports the need for a multidisciplinary approach including infectious disease, orthopedic surgery and reconstructive urology in order to address this complex clinical condition.

The Antistaphylococcal Activity of Amoxicillin/Clavulanic Acid, Gentamicin, and 1,8-Cineole Alone or in Combination and Their Efficacy through a Rabbit Model of Methicillin-Resistant Staphylococcus aureus Osteomyelitis

The aim of this research paper is to test the antistaphylococcal effect of 1,8-cineole, amoxicillin/clavulanic acid (AMC), and gentamicin, either separately or in combination against three Staphylococcus aureus strains isolated from patients suffering from osteomyelitis. This activity was tested in vitro by using the microdilution method and the checkerboard assay. The efficacy of these three antibacterial agents was then tested in vivo by using an experimental model of methicillin-resistant S. aureus osteomyelitis in rabbits. This efficacy was assessed after four days of treatment by counting the number of bacteria in the bone marrow. The obtained results in vitro showed that the combination of the AMC with gentamicin did not induce a synergistic effect, whereas the combination of the two antibiotics with 1,8-cineole did. This effect is stronger when AMC is combined with 1,8-cineole as a total synergistic effect was obtained on the three strains used (FIC ≤ 0.5). In vivo, a significant reduction was noted in the number of colonies in the bone marrow when rabbits were treated with AMC associated with either 1,8-cineole or gentamicin compared to rabbits treated with AMC, gentamicin, or 1,8-cineole alone. These results demonstrated that 1,8-cineole showed a synergistic effect in combination with both AMC and gentamicin, which offer possibilities for reducing antibiotic usage. Also, the AMC associated with 1,8-cineole could be used to treat MRSA osteomyelitis.

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.

Facial trauma followed by osteomyelitis - Case report

Introduction

Osteomyelitis is an inflammatory-infectious state that may involve trabecular bone, cortical bone, bone marrow and periosteum. The source of the infection may be hematogenic, acquired from an adjoining infectious focus or by direct inoculation into the bone. Its treatment involves antibiotic administration and surgery, but its management remains challenging.

Presentation of case

A 76-year-old male patient with a history of car accident 3 months earlier sought hospital care with nasal fracture and loss of substance in the right frontotemporal region, where a pectoral muscle free graft was performed to reconstruct the facial defect. The grafted region had hyperemic edges, necrotic appearance, purulent discharge and bone exposure in the nasal dorsum. The initial diagnostic hypothesis was an infectious process due to graft rejection, with likely evolution to osteomyelitis. The surgical procedure was performed by a multidisciplinary team and the patient received the antibiotic regimen according to the antibiogram, with hospital discharge after 39 days of hospitalization.

Discussion

Treatment of osteomyelitis requires the combination of antimicrobial therapy and surgery. Despite surgical and chemotherapeutic advances, it is a difficult condition to treat and there is no universally accepted protocol for treatment.

Conclusion

Surgical treatment was essential for stabilization of the condition. Due to the complexity of this type of infection in the craniofacial region, planning and execution must be carried out through a multidisciplinary team.

Use of the Keystone Perforator Island Flap in the treatment of chronic lower extremity wounds complicated by osteomyelitis

INTRODUCTION

Reconstruction of chronic lower extremity wounds can be especially challenging when these wounds are complicated by osteomyelitis. They require the joint expertise of plastic and orthopaedic surgeons.

METHODS

We report our experience using the Keystone Perforator Island Flap following wound and bone debridement as a valuable surgical tool for coverage of complex wounds with bone infection.

RESULTS

Twelve patients underwent similar procedures with overall good outcomes, although two patients experienced a complication, specifically partial flap necrosis and wound dehiscence subsequent to recurrent osteomyelitis. We also reviewed the underlying physiological mechanisms of employing the Keystone flap in order to demonstrate its advantages and efficacy.

CONCLUSION

Our results confirm that the Keystone flap can be a safe, reliable and effective method for coverage of soft tissue defects and the preservation of bone integrity in the management of patients with chronic osteomyelitis.

Long Noncoding RNA FAM83H-AS1 Modulates SpA-Inhibited Osteogenic Differentiation in Human Bone Mesenchymal Stem Cells

Osteomyelitis, an infection of the bone and bone marrow, imposes a heavy burden on public health care systems owing to its progressive bone destruction and sequestration. Human bone mesenchymal stem cells (hBMSCs) play a key role in the process of bone formation, and mounting evidence has confirmed that long noncoding RNAs (lncRNAs) are involved in hBMSC osteogenic differentiation. Nevertheless, the exact function and molecular mechanism of lncRNAs in osteogenic differentiation during osteomyelitis development remain to be explored. In this study, hBMSCs were treated with staphylococcal protein A (SpA) during osteogenic differentiation induction to mimic osteomyelitis in vitro The results of lncRNA microarray analysis revealed that FAM83H-AS1 presented the lowest expression among the significantly downregulated lncRNAs. Functionally, ectopic expression of FAM83H-AS1 contributed to osteogenic differentiation of SpA-induced hBMSCs. Additionally, our findings revealed that FAM83H-AS1 negatively regulated microRNA 541-3p (miR-541-3p), and WNT3A was validated as a target gene of miR-541-3p. Mechanically, FAM83H-AS1 elevated WNT3A expression by competitively binding with miR-541-3p. Lastly, it was demonstrated that FAM83H-AS1/miR-541-3p/WNT3A ameliorated SpA-mediated inhibition of the osteogenic differentiation of hBMSCs, which provided a novel therapeutic strategy for patients with osteomyelitis.

Risk factors associated with recurrence of extremity osteomyelitis treated with the induced membrane technique

INTRODUCTION

Our aim was to observe the efficacy of the induced membrane technique in the treatment of extremity osteomyelitis and to analyse the causes of infection recurrence and its risk factors.

METHODS

We retrospectively analysed 424 cases of extremity osteomyelitis treated with the induced membrane technique in our department between May 2013 and June 2017. Infection recurrence time, recurrence sites and other relevant information were collected, summarized, and analysed.

RESULTS

A total of 424 patients were considered as "cured" of osteomyelitis after the first stage and the induced membrane technique was performed to rebuild the bone defects. After a mean follow-up of 31.6 (16-63) months, 52 patients had recurrence of infection, including 42 tibias and 10 femurs. The recurrence rate was 12.26%. Symptoms were relieved in 16 patients after intravenous antibiotic treatment. In the remaining 36 cases (8.49%), the infection was uncontrolled by intravenous antibiotics and surgical debridement was performed. The recurrence rate of infection of the tibia (16.22%) was higher than that of the femur (8.70%). The recurrence rate of post-traumatic osteomyelitis (14.66%) was significantly higher than that of hematogenous osteomyelitis (2.41%). Patients in whom Pseudomonas aeruginosa was isolated at the first stage had a recurrence rate of 28% (7/25), which was higher than that with the other isolated bacteria. Logistic regression analysis showed that repeated operations (≥3), post-traumatic osteomyelitis, and internal fixation at the first stage were risk factors for recurrence of infection, with odds ratios (ORs) of 2.30, 5.53 and 5.28 respectively.

CONCLUSIONS

The induced membrane technique is an effective method in the treatment of extremity osteomyelitis, although infection recurs in some cases. Repeated operations, post-traumatic osteomyelitis, and internal fixation at the first stage were risk factors for recurrence of infection. P. aeruginosa isolated at the first stage, tibia osteomyelitis, the presence of sinus, or flaps may also be associated with recurrence of infection.

Staphylococcus Aureus Osteomyelitis as an Inducer of Tolerance to Escherichia Coli Pyelonephritis: an Experimental Study

The high incidence of osteomyelitis in vulnerable populations like those with multiple injuries or elderly undergoing joint arthroplasties generates the question what may be their responses to subsequent infection by high virulent isolates. Rabbits were subject to two operations at three week intervals; sham osteomyelitis and sham pyelonephritis (group S); sham osteomyelitis and Escherichia coli pyelonephritis (group P); and Staphylococcus aureus osteomyelitis and E. coli pyelonephritis (group OP). Survival was recorded; cytokine stimulation of circulating mononuclear cells (PBMCs) and tissue myeloperoxidase (MPO) activity and bacterial growth were monitored. In some experiments, dalbavancin treatment was given before pyelonephritis. Healthy PBMCs were pre-treated with bone homogenate, S. aureus or both. Mortality of groups S, P and OP after induction of pyelonephritis was 0%, 50% and 8.3% respectively. Tumour necrosis factor-alpha (TNFα) production by PBMCs was significantly lower in the OP group at 48 hours. E. coli bacterial load was similar in groups P and OP at death or sacrifice whereas the MPO activity of group OP was decreased. Production of TNFα was further decreased among dalbavancin treated rabbits; in these rabbits tissue MPO was increased. TNFα production decreased when healthy PBMCs pre-treated with bone homogenate, S. aureus (HKSA) or both were stimulated with E. coli (HKEC); production was further decreased in the presence of anti-TLR4 and anti-TLR9. It is concluded that staphylococcal osteomyelitis modulated the innate immune responses of the host leading to protection from death by highly virulent E. coli. Tolerance to TLR ligands is the most likely mechanism of action.

Scleral ossicles: angiogenic scaffolds, a novel biomaterial for regenerative medicine applications

Given the current prolonged life expectancy, various pathologies affect increasingly the aging subjects. Regarding the musculoskeletal apparatus, bone fragility induces more susceptibility to fractures, often not accompanied by good ability of self-repairing, in particular when critical-size defects (CSD) occur. Currently orthopedic surgery makes use of allografting and autografting which, however, have limitations due to the scarce amount of tissue that can be taken from the donor, the possibility of disease transmission and donor site morbidity. The need to develop new solutions has pushed the field of tissue engineering (TE) research to study new scaffolds to be functionalized in order to obtain constructs capable of promoting tissue regeneration and achieve stable bone recovery over time. This investigation focuses on the most important aspect related to bone tissue regeneration: the angiogenic properties of the scaffold to be used. As an innovative solution, scleral ossicles (SOs), previously characterized as natural, biocompatible and spontaneously decellularized scaffolds used for bone repair, were tested for angiogenic potential and biocompatibility. To reach this purpose, in ovo Chorioallantoic Membrane Assay (CAM) was firstly used to test the angiogenic potential; secondly, in vivo subcutaneous implantation of SOs (in a rat model) was performed in order to assess the biocompatibility and the inflammatory response. Finally, thanks to the analysis of mass spectrometry (LCMSQE), the putative proteins responsible for the SO angiogenic properties were identified. Thus, a novel natural biomaterial is proposed, which is (i) able to induce an angiogenic response in vivo by subcutaneous implantation in a non-immunodeficient animal model, (ii) which does not induce any inflammatory response, and (iii) is useful for regenerative medicine application for the healing of bone CSD.

Oral amoxicillin and amoxicillin-clavulanic acid: properties, indications and usage

BACKGROUND

Amoxicillin has been in use since the 1970s; it is the most widely used penicillin both alone and in combination with the β-lactamase clavulanic acid.

OBJECTIVES

In this narrative review, we re-examine the properties of oral amoxicillin and clavulanic acid and provide guidance on their use, with emphasis on the preferred use of amoxicillin alone.

SOURCES

Published medical literature (MEDLINE database via Pubmed).

CONTENT

While amoxicillin and clavulanic acid have similar half-lives, clavulanic acid is more protein bound and even less heat stable than amoxicillin, with primarily hepatic metabolism. It is also more strongly associated with gastrointestinal side effects, including Clostridium difficile infection, and, thus, in oral combination formulations, limits the maximum daily dose of amoxicillin that can be given. The first ratio for an amoxicillin-clavulanic acid combination was set at 4:1 due to clavulanic acid's high affinity for β-lactamases; ratios of 2:1, 7:1, 14:1 and 16:1 are currently available in various regions. Comparative effectiveness data for the different ratios are scarce. Amoxicillin-clavulanic acid is often used as empiric therapy for many of the World Health Organization's Priority Infectious Syndromes in adults and children, leading to extensive consumption, when some of these syndromes could be handled with a delayed antibiotic prescription approach or amoxicillin alone.

IMPLICATIONS

Using available epidemiological and pharmacokinetic data, we provide guidance on indications for amoxicillin versus amoxicillin-clavulanic acid and on optimal oral administration, including choice of combination ratio. More data are needed, particularly on heat stability, pharmacodynamic effects and emergence of resistance in 'real-world' clinical settings.

Overcoming stability challenges during continuous intravenous administration of high-dose amoxicillin using portable elastomeric pumps

While treatment of serious infectious diseases may require high-dose amoxicillin, continuous infusion may be limited by lack of knowledge regarding the chemical stability of the drug. Therefore, we have performed a comprehensive study so as to determine the chemical stability of high-dose amoxicillin solutions conducive to safe and effective continuous intravenous administration using portable elastomeric pumps. First, amoxicillin solubility in water was assessed within the range of 25 to 300 mg/mL. Then, amoxicillin solutions were prepared at different concentrations (25, 50, 125, 250 mg/mL) and stored in different conditions (5±2°C, 25±1°C, 30±1°C and 37±1°C) to investigate the influence of concentration and temperature on the chemical stability of amoxicillin. Finally, its stability was assessed under optimized conditions using a fully validated HPLC-UV stability-indicating method. Degradation products of amoxicillin were investigated by accurate mass determination using high-resolution mass spectrometry. Amoxicillin displayed limited water solubility requiring reconstitution at concentrations below or equal to 150 mg/mL. Amoxicillin degradation were time, temperature as well as concentration-dependent, resulting in short-term stability, in particular at high concentrations. Four degradation products of amoxicillin have been identified. Among them, amoxicilloic acid and diketopiperazine amoxicillin are at risk of allergic reaction and may accumulate in the patient. Optimized conditions allowing for continuous infusion of high-dose amoxicillin has been determined: amoxicillin should be reconstituted at 25 mg/mL and stored up to 12 hours at room temperature (22 ± 4°C) or up to 24 hours between 4 and 8°C.