Infected Bone Defects Research Articles

Glucose-primed PEEK orthopedic implants for antibacterial therapy and safeguarding diabetic osseointegration

Diabetic infectious microenvironment (DIME) frequently leads to a critical failure of osseointegration by virtue of its main peculiarities including typical hyperglycemia and pathogenic infection around implants. To address the plaguing issue, we devise a glucose-primed orthopedic implant composed of polyetheretherketone (PEEK), Cu-chelated metal-polyphenol network (hauberk coating) and glucose oxidase (GOx) for boosting diabetic osseointegration. Upon DIME, GOx on implants sostenuto consumes glucose to generate H2O2, and Cu liberated from hauberk coating catalyzes the H2O2 to highly germicidal •OH, which massacres pathogenic bacteria through photo-augmented chemodynamic therapy. Intriguingly, the catalytic efficiency of the coating gets greatly improved with the turnover number (TON) of 0.284 s−1. Moreover, the engineered implants exhibit satisfactory cytocompatibility and facilitate osteogenicity due to the presence of Cu and osteopromotive polydopamine coating. RNA-seq analysis reveals that the implants enable to combat infections and suppress pro-inflammatory phenotype (M1). Besides, in vivo evaluations utilizing infected diabetic rat bone defect models at week 4 and 8 authenticate that the engineered implants considerably elevate osseointegration through pathogen elimination, inflammation dampening and osteogenesis promotion. Altogether, our present study puts forward a conceptually new tactic that arms orthopedic implants with glucose-primed antibacterial and osteogenic capacities for intractable diabetic osseointegration.

Self-promoted electroactive biomimetic mineralized scaffolds for bacteria-infected bone regeneration

Infected bone defects are a major challenge in orthopedic treatment. Native bone tissue possesses an endogenous electroactive interface that induces stem cell differentiation and inhibits bacterial adhesion and activity. However, traditional bone substitutes have difficulty in reconstructing the electrical environment of bone. In this study, we develop a self-promoted electroactive mineralized scaffold (sp-EMS) that generates weak currents via spontaneous electrochemical reactions to activate voltage-gated Ca2+ channels, enhance adenosine triphosphate-induced actin remodeling, and ultimately achieve osteogenic differentiation of mesenchymal stem cells by activating the BMP2/Smad5 pathway. Furthermore, we show that the electroactive interface provided by the sp-EMS inhibits bacterial adhesion and activity via electrochemical products and concomitantly generated reactive oxygen species. We find that the osteogenic and antibacterial dual functions of the sp-EMS depend on its self-promoting electrical stimulation. We demonstrate that in vivo, the sp-EMS achieves complete or nearly complete in situ infected bone healing, from a rat calvarial defect model with single bacterial infection, to a rabbit open alveolar bone defect model and a beagle dog vertical bone defect model with the complex oral bacterial microenvironment. This translational study demonstrates that the electroactive bone graft presents a promising therapeutic platform for complex defect repair.

Heterostructured piezocatalytic nanoparticles with enhanced ultrasound response for efficient repair of infectious bone defects

Infection of bone defects remains a challenging issue in clinical practice, resulting in various complications. The current clinical treatments include antibiotic therapy and surgical debridement, which can cause drug-resistance and potential postoperative complications. Therefore, there is an urgent need for an efficient treatment to sterilize and promote bone repair in situ. In this work, an ultrasound responsive selenium modified barium titanate nanoparticle (Se@BTO NP) was fabricated, which exhibited significant antibacterial and bone regeneration effects. Selenium nanoparticle (Se NP) was modified on the surface of barium titanate nanoparticle (BTO NP) to form heterostructure, which facilitated the second distribution of piezo-induced carriers under ultrasound (US) irradiation and improved the separation of electron–hole pairs. The Se@BTO NPs exhibited remarkable antibacterial efficiency with an antibacterial rate of 99.23 % against Staphylococcus aureus (S.aureus) and significantly promoted the osteogenic differentiation under ultrasound irradiation. The in vivo experiments exhibited that Se@BTO NPs successfully repaired the femoral condylar bone defects of rats infected by S.aureus, resulting in significant promotion of bone regeneration. Overall, this work provided an innovative strategy for the utilization of US responsive nanomaterials in efficient bacteria elimination and bone regeneration. Statement of significanceInfectious bone defects remain a challenging issue in clinical practice. Current antibiotic therapy and surgical debridement has numerous limitations such as drug-resistance and potential complications. Herein, we designed an innovative ultrasound responsive selenium modified barium titanate nanoparticle (Se@BTO NP) to achieve efficient non-invasive bacteria elimination and bone regeneration. In this work, Se@BTO nanoparticles can enhance the separation of electrons and holes, facilitate the transfer of free carriers due to the cooperative effect of ultrasound induced piezoelectric field and heterojunction construction, and thus exhibit remarkable antibacterial and osteogenesis effect. Overall, our study provided a promising strategy for the utilization of piezocatalytic nanomaterials in efficient antibacterial and bone regeneration.

Antisense yycF and BMP-2 co-delivery gelatin methacryloyl and carboxymethyl chitosan hydrogel composite for infective bone defects regeneration

Repairing infected bone defects remains a challenge in clinical work. Intractable bacterial infections and insufficient osseointegration are major concerns for infected bone defects. To address these issues, we developed a gelatin methacryloyl (GelMA) and carboxymethyl chitosan (CMCS) composite hydrogel with BMP-2 growth factor and GO based antisense technology supported by a PLGA spring. In vitro, photo-crosslinked GelMA composite hydrogels shown excellent biocompatibility and degradability. Relying on the release of BMP-2 from the composite hydrogel provides osteogenic effects. The antisense yycF and BMP-2 were released with the degradation of GelMA and CMCS composite hydrogel. In terms of antimicrobial properties, CMCS, GO and post-transcriptional regulatory antisense yycF from the composite hydrogel synergistically kill S. aureus. In vivo, we implanted the composite hydrogel in a rat model of S. aureus infected femur defect, effectively accelerating bone healing in an infectious microenvironment. This research provides a novel biomaterial that is both antimicrobial and promotes bone regeneration, with the potential to treat infected bone defects.

Dual Photo‐Enhanced Interpenetrating Network Hydrogel with Biophysical and Biochemical Signals for Infected Bone Defect Healing (Adv. Healthcare Mater. 25/2023)

Dual Photo‐Enhanced Interpenetrating Network Hydrogel with Biophysical and Biochemical Signals for Infected Bone Defect Healing (Adv. Healthcare Mater. 25/2023)

The polymicrobial infection affects the infection recurrence rate (not failure) in treating femoral and tibial bone defects with the Masquelet technique-a comparative retrospective analysis of 54 patients with mono- and polymicrobial infections.

This study evaluated whether polymicrobial infection affects reoperation rates due to infection recurrence and treatment failure with the Masquelet technique in infected posttraumatic segmental bone defects of the femur and tibia. We retrospectively analyzed patients treated between 2012 and 2021 in two trauma referral centers. We evaluated demographic data, injury, treatment, infection recurrence, failures, and bone healing rates according to whether the infection was mono- or polymicrobial. After uni-bivariate analysis between patients with polymicrobial and monomicrobial infection, we identified the variables associated with infection recurrence and failure through multivariate analysis. We analyzed 54 patients, 30 (55.55%) with tibial and 24 (44.44%) femoral segmental bone defects, with a mean follow-up of 41.7 ± 15.0months. Forty-four (81.48%) presented monomicrobial, and 10 (18.51%) polymicrobial infections. Comparatively, the need for soft tissue reconstruction and the infection recurrence rate was significantly higher in patients with polymicrobial infections. There was no significant difference in the failure rate (20 vs. 6.81% p = 0.23). Multivariable logistic regression analysis identified the polymicrobial infection as the only independent variable associated with infection recurrence (Odds Ratio = 11.07; p = 0.0017). Our analysis suggests that polymicrobial infection is associated with a higher risk of infection recurrence in treating the femur and tibia segmental bone defects with the Masquelet technique. This information can help surgeons to inform patients about this and give them a realistic expectation of the outcome and the possibility of reoperation.

Treatment of infected bone defects with the induced membrane technique.

This study aimed to evaluate the effectiveness of the induced membrane technique for treating infected bone defects, and to explore the factors that might affect patient outcomes. A comprehensive search was performed in PubMed, Embase, and the Cochrane Central Register of Controlled Trials databases between 1 January 2000 and 31 October 2021. Studies with a minimum sample size of five patients with infected bone defects treated with the induced membrane technique were included. Factors associated with nonunion, infection recurrence, and additional procedures were identified using logistic regression analysis on individual patient data. After the screening, 44 studies were included with 1,079 patients and 1,083 segments of infected bone defects treated with the induced membrane technique. The mean defect size was 6.8 cm (0.5 to 30). After the index second stage procedure, 85% (797/942) of segments achieved union, and 92% (999/1,083) of segments achieved final healing. The multivariate analysis with data from 296 patients suggested that older age was associated with higher nonunion risk. Patients with external fixation in the second stage had a significantly higher risk of developing nonunion, increasing the need for additional procedures. The autografts harvested from the femur reamer-irrigator-aspirator increased nonunion, infection recurrence, and additional procedure rates. The induced membrane technique is an effective technique for treating infected bone defects. Internal fixation during the second stage might effectively promote bone healing and reduce additional procedures without increasing infection recurrence. Future studies should standardize individual patient data prospectively to facilitate research on the affected patient outcomes.

Bone Transport through Induced Membrane versus Conventional Bone Transport in Management of Infected long bone defects of Lower Limbs: a randomized controlled trial.

To compare bone transport through induced membrane (BTM) and conventional bone transport (BT) regarding docking site union and infection recurrence in management of infected long bone defects. prospective randomized controlled study. tertiary level center. 30 patients with infected non-united long bone fractures of lower limbs. 15 patients treated by BTM in group (A) and 15 patients treated by BT in group (B). External fixation time (EFT), External fixation index (EFI), Docking time (DT). Bone and functional outcomes evaluated by the Association for the Study and Application of the Method of Ilizarov (ASAMI) scoring system. Postoperative complications evaluated according to Paley's classification. The mean docking time (DT) was significantly lower in BTM group in comparison to BT group (3.6 ± 0.82 months vs 4.8 ± 0.86 months respectively; P value 0.001). Docking site non-union and infection recurrence were significantly lower in BTM group in comparison to BT group (0% vs 40%; P value 0.02 and 0% vs 33.3%; P value 0.04 respectively) with no significant difference in EFI (P value 0.08). This is the first prospective randomized controlled study comparing BTM and BT techniques showing that BTM had significantly faster docking site union, lower incidence of postoperative complications including docking site non-union and infection recurrence rates and lower number of additional procedures needed at the expense of two staged operation in comparison to BT.

Hemilateral bone longitudinal transport technique for the treatment of hemilateral defects of long bones of lower limbs

To explore clinical efficacy of Ilizarov hemilateral bone longitudinal transport technique in treating hemilateral bone defects associated with chronic osteomyelitis of lower extremity long bones. Clinical data of 13 patients with hemilateral bone defects caused by chronic osteomyelitis of lower extremity long bones and treated by Ilizarov hemilateral bone longitudinal transport technique were retrospective analyzed, including 10 males and 3 female, aged from 14 to 55 years old;4 patients occurred femoral and 9 patients occurred tibial;10 patients were diagnosed as traumatic osteomyelitis and 3 patients as hematogenous osteomyelitis. The anatomical classification of Cierny-Mader in 13 patients was type Ⅲ. Bone and wound healing, postopertaive complication, and bony and functional results were observed by Paley evaluation standard. After removing external fixator, all patients were followed up from 6 to 70 months. Transporting time ranged from 54 to 158 d. And the time in external fixation ranged from 6.8 to 19.5 months. External fixation index (EFI) ranged from 1.23 to 1.6 months/cm. According to Paley's evaluation criteria, bony results were excellent in 13 patients;functional results showed excellent in 12 patients and good in 1 patient. Two patients occurred poor union on the docking sites and healed with autogenous iliac bone graft. The callus at the extended area was poorly mineralized and improved significantly when treated with low-intensity pulsed ultrasound in one patient. All patients had good wound healing without recurrence of osteomyelitis and refracture. There was no vascular and nerve injury and axial deviation in all patients and they were satisfied with the appearance and function of lower limbs. The range of motion of knee and ankle joint before operation was 120 ° to 150 ° and 35 °to 80 ° respectively, and at the latest follow-up was 110 ° to 140 ° and 30 ° to 75 ° . Ilizarov hemilateral bone longitudinal transport technique is effective in treating infective hemilateral bone defects of lower extremity long bones, which could not only simplify architecture of external fixation, but also reduce the number of fixation pins, shorten the time in external fixator and decrease the incidence of pin tract infection. However, this technique is highly demanding, and the growth of callus in extended region and healing of bone apposition should be noticed.

RFSAV promotes Staphylococcus aureus-infected bone defect healing via IL-13- mediated M2 macrophage polarization

Staphylococcus aureus (S. aureus) contamination commonly occurs in orthopedic internal fixation operations, leading to a delayed healing of the defected bone tissue. However, antibiotic treatments are ineffective in dealing with S. aureus bone infections due to the rise in multiple antimicrobial resistances. Here, we reported the protective effects of a recombinant five-antigen S. aureus vaccine (rFSAV) in an S. aureus infected bone defect model. In this study, we found the number of M2 macrophages markedly increased in the defect site and played a critical role in the healing of defected bone mediated by rFSAV. Mechanistically, rFSAV mediated increased level of IL-13 in bone defect site predominant M2 macrophage polarization. In summary, our study reveals a key role of M2 macrophage polarization in the bone regeneration process in S. aureus infection induced bone defect, which provide a promising application of rFSAV for the treatment of bone infection for orthopedic applications.

Electrospinning Fibers Modified with Near Infrared Light‐Excited Copper Nanoparticles for Antibacterial and Bone Regeneration

AbstractBone infection is an inflammatory bone disease caused by infectious microorganisms, which can lead to progressive bone destruction and loss. It is still an urgent and unmet clinical need to develop a rapid and effective sterilized method to reduce bone infection. In this study, near‐infrared (NIR) light‐responsive polydopamine (PDA) adherent Copper nanoparticles (Cu‐NPs) are constructed using electrospun poly lactic acid (PLLA) fibers as a substrate (PLLA@PDA/Cu). Dopamine (DA) is self‐polymerized to synthesize the PDA on the fiber surface, which can reduce Cu2+ to form Cu‐NPs. Results show that the addition of PDA and Cu2+ significantly improves the hydrophilicity and bioactivity of the prepared PLLA@PDA/Cu composite fibers, demonstrating superior physiological stability. Due to the unique photothermal properties of Cu‐NPs, PLLA@PDA/Cu is able to generate a large amount of reactive oxygen species under 808 nm NIR laser irradiation, with a photothermal conversion efficiency of 23.7%. The antimicrobial effect of Cu‐NPs is synergistic with their photothermal effect, which potentiated the antibacterial rate of composite fibers . The results of cell experiments show that this composite fiber demonstrates satisfactory osteogenic and angiogenic properties. In conclusion, a photothermal antibacterial PLLA@PDA/Cu composite fiber with great potential in healing infectious bone defects is successfully engineered.

CoFe2O4/MXene nanosheets modified hydrogel on PEEK with phototherapeutic and GPx-Mimetic activities for anti-pathogens in infectious bone defect repairment

Polyetheretherketone (PEEK), as a promising alternative for hard tissue implant, still has limitations in anti-pathogens for coping with the clinical challenge. To reverse this situation, CoFe2O4/MXene nanosheets modified hydrogel was spin-coated on PEEK mediated by polydopamine to endow PEEK with favorable anti-bacterial activity. The modified PEEK implant exhibits the property of photothermal therapy (PTT) for local heat, photodynamic therapy (PDT), and chemodynamic therapy (CDT) for reactive oxygen species (ROS) accumulation to realize robust anti-pathogens. The antibacterial effect can be further enhanced by glutathione (GSH) consumption owing to the glutathione peroxides (GPx)-mimetic activity of CM2. In addition, we investigated the specific effects of the designed materials on bacteria, and the experimental results showed that constructed CM2 can lead to the DNA and protein of bacterial leakage and ATP synthesis decreased, ultimately eliminating more than 99% of bacteria. Furthermore, the sample exhibits favorable blood and cell compatibility with broad prospects in clinical application. Overall, a hydrogel coating-PEEK system with robust antibacterial properties has been manufactured in our work, which can not only exhibit compatibility, but also effectively avoid implant-related infection, which shows great promise for infectious bone defect repairment.

Dual Photo-Enhanced Interpenetrating Network Hydrogel with Biophysical and Biochemical Signals for Infected Bone Defect Healing.

The healing of infected bone defects (IBD) is a complex physiological process involving a series of spatially and temporally overlapping events, including pathogen clearance, immunological modulation, vascularization, and osteogenesis. Based on the theory that bone healing is regulated by both biochemical and biophysical signals, in this study, a copper doped bioglass (CuBGs)/methacryloyl-modified gelatin nanoparticle (MA-GNPs)/methacrylated silk fibroin (SilMA) hybrid hydrogel is developed to promote IBD healing. This hybrid hydrogel demonstrates a dual-photocrosslinked interpenetrating network mechanism, wherein the photocrosslinked SilMA as the main network ensures structural integrity, and the photocrosslinked MA-GNPs colloidal network increases strength and dissipates loading forces. In an IBD model, the hydrogel exhibits excellent biophysical characteristics, such as adhesion, adaptation to irregular defect shapes, and in situ physical reinforcement. At the same time, by sequentially releasing bioactive ions such as Cu2+ , Ca2+ , and Si2+ ions from CuBGs on demand, the hydrogel spatiotemporally coordinates antibacterial, immunomodulatory and bone remodeling events, efficiently removing infection and accelerating bone repair without the use of antibiotics or exogenous recombinant proteins. Therefore, the hybrid hydrogel can be used as a simple and effective method for the treatment of IBD.

Induced membrane technique in the treatment of infected tibial bone defect: A retrospective study.

To investigate the effect of the induced membrane technique (IMT) in the treatment of infected tibial bone defect. IMT is a 2-stage procedure dedicated to reconstruction of bone defects of the limbs. Treating injuries of the tibia characterized by segmental bone loss, severe damage to the soft tissue, and a conjoining infection is a challenge using IMT. A retrospective study was performed among the patients treated using IMT for infected tibial bone defect between 2017 and 2020. The complications were recorded, and the bone defect union and the functional results were evaluated by Paley method. All patients were followed up for at least 1 year. We included 12 patients (11 males) with a mean age of 44.5 years (range 19-65). The mean length of bone defect was 26.7 mm (range 10-60). The mean interval between the stage 1 and the stage 2 of the procedure was 11.8 weeks (range 4-32). At a mean follow-up of 18.08 months (range 12-32), bone union was achieved in all cases in a mean time of 8 months (range 5-16) without infection recurrence, where 1 patient received additional bone grafting. The joint function recovered well for the patients and the rate of functionally excellent and good results was 9/12. IMT in the treatment of infected tibial bone defect offers the advantages of simple operation, use of a smaller amount of autograft bone, and low recurrence rate of infection.

Cyclic mechanical stretch pre-stimulated bone marrow mesenchymal stem cells promote the healing of infected bone defect in a mouse model.

Cyclic mechanical stretch (CMS) is an effective method to accelerate mesenchymal stem cells (MSCs) differentiation. Here, we investigated CMS pre-stimulated bone marrow MSCs (CMS-BMSCs), characterized and evaluated the therapeutic potential of CMS-BMSCs on the treatment of infected bone defect in mouse model. BMSCs were obtained from C57BL/6J mice and then subjected to CMS. The osteogenic differentiation capacity of BMSCs was evaluated by alkaline phosphatase (ALP) assay, Alizarin Red staining, qRT-PCR and Western blot. The pre-stimulated BMSCs were transplanted into infected bone defect mice, osteogenesis, antibacterial effects, and inflammatory responses were examined. CMS significantly increased ALP activity and the expression of osteoblastic genes (col1a1, runx2, and bmp7) and enhanced osteogenic differentiation and nrf2 expression of BMSCs. Transplantation of CMS pre-stimulated BMSCs promoted the healing of infected bone defect in mice, enhanced antibacterial effects, and reduced inflammatory responses in the mid-sagittal section of the fracture callus. CMS pre-stimulated BMSCs enhance the healing of infected bone defects in a mouse model, suggesting a potential therapeutic strategy for treating infected bone defects. This article is protected by copyright. All rights reserved.

Treatment outcome of the Masquelet technique in 195 infected bone defects–A single-center, retrospective case series

BackgroundThe Masquelet technique is a surgical procedure for the reconstruction of bone defects. During the first step, an osteosynthetically stabilized defect is filled with a cement spacer. The spacer induces a foreign body membrane, called a Masquelet membrane. In a follow-up procedure, the spacer is replaced by a bone graft, which ossifies in the subsequent phase. Material and MethodsA total of 171 patients with 195 septic bone defects on the extremities that had been treated with the Masquelet procedure at the BG Klinikum in Hamburg, Germany, from 2011 to 2021 were retrospectively analysed, comparing patients who reached full weight and load bearing on the affected extremity to those who failed to do so. Defect size and configuration, microbiological results and treatment methods as well as comorbidities and epidemiologic data were analysed for factors influencing the treatment outcome. ResultsIn all, 113[66%] of the patients were male, and 58[34%] were female, with an age distribution of 52 +/-16 years. Out of 171 patients, 24 patients had two defects. The number of patients that reached full weight bearing was 152[89%], the follow-up period was 2 +/-1 years (median +/- SD). Full weight bearing capability was negatively by the defect size as defects >62 mm tended to be less likely to reach full weight bearing than smaller defects. A secondary stabilization with an internal stabilization was applied in 58[34%] of all patients and positively influenced the attainment of full weight and load bearing. DiscussionWith 171 patients and 195 septic bone defects treated at a single centre with the Masquelet Technique, this study represents a comparably large cohort. Demographics, defect characteristics and treatment outcomes did not differ from those of other cohorts described in the literature. Defects larger than 62 mm showed lower chances to reach full weight bearing and can be defined as "critical defect size" for the Masquelet technique based on our data.

Composite PLLA/Ag@SiO2 microspheres for bone regeneration in infected bone defects

Repairing bone defects is particularly challenging when an infection is presented. In this study, poly(L-lactic) (PLLA) nanofibrous microspheres (large microspheres) were used as cell carriers to simulate the nanofibrous structure of the extracellular matrix. A planet-satellite composite microsphere with large microspheres and small microspheres was constructed by bonding hollow Ag@SiO2 nanospheres (small microspheres) to nanofibrous PLLA microspheres. According to the results, PLLA nanofibrous microspheres activated by EDC and NHS can firmly combine with Ag@SiO2 nanospheres. The composite microspheres demonstrated excellent drug release functions, antibacterial properties, and biocompatibility and promoted cell adhesion and differentiation in vitro. The bone repair function of composite microspheres loaded with BMP2 growth factor was evaluated in rat that were infected with bacteria and exhibited skull defects. A four-week study showed that these microspheres significantly promoted bone regeneration in infected bone. These multifunctional microspheres could revolutionize bone repair and provide a much-needed solution for those suffering from infected bone defects.

Bifunctional Hydrogel-Integrated 3D Printed Scaffold for Repairing Infected Bone Defects.

The clinical treatment of infectious bone defects is difficult and time-consuming due to the coexistence of infection and bone defects, and the simultaneous control of infection and repair of bone defects is considered a promising therapy. In this study, a dual-drug delivery scaffold system was fabricated by the combination of a three-dimensional (3D) printed scaffold with hydrogel for infected bone defects repair. The 3D printed polycaprolactone scaffold was incorporated with biodegradable mesoporous silica nanoparticles containing the small molecular drug fingolimod (FTY720) to provide structural support and promote angiogenesis and osteogenesis. The vancomycin (Van)-loaded hydrogel was prepared from aldehyde hyaluronic acid (AHA) and carboxymethyl chitosan (NOCC) by the Schiff base reaction, which can fill the pores of the 3D-printed scaffold to produce a bifunctional composite scaffold. The in vitro results demonstrated that the composite scaffold had Van concentration-dependent antimicrobial properties. Furthermore, the FTY720-loaded composite scaffold demonstrated excellent biocompatibility, vascularization, and osteogenic ability in vitro. In the rat femoral defect model with bacterial infection, the dual-drug composite scaffold showed a better outcome in both infection control and bone regeneration compared to other groups. Therefore, the prepared bifunctional composite scaffold has potential application in the treatment of infected bone defects.

Fabrication, bacteriostasis and osteointegration properties researches of the additively-manufactured porous tantalum scaffolds loading vancomycin.

Infected bone defects (IBDs) remains a challenging problem for orthopedists. Clinically, routine management for IBDs has two stages: debridement and systematic antibiotics administration to control infection, and secondary grafting to repair bone defects. Whereas the efficacy is not satisfactory, because the overuse of antibiotics may lead to systemic toxicity, and the emergence of drug-resistant bacteria, as well as the secondary surgery would cause additional trauma and economic burden to the patients. Therefore, it is imperative to develop a novel scaffold for one-stage repair of IBDs. In this study, vancomycin (Van) was encapsulated into poly(lactic co-glycolic acid) (PLGA) microspheres through the double emulsion method, which were then loaded into the additively-manufactured porous tantalum (AM-Ta) through gelatin methacryloyl (GelMA) hydrogel to produce the composite Ta/GelMA hydrogel (Gel)/PLGA/vancomycin(Van) scaffolds for repairing IBDs. Physiochemical characterization of the newly-developed scaffold indicated that the releasing duration of Van was over 2 weeks. Biological experiments indicated good biocompatibility of the composite scaffold, as well as bacteriostasis and osteointegration properties, which showed great potential for clinical application. The construction of this novel scaffold would provide new sight into the development of orthopaedic implants, shedding a novel light on the treatment of IBDs.

Tuberculous Osteomyelitis of the Fifth Metatarsal Treated Using the Induced Membrane Technique: A Case Report

Tuberculous osteomyelitis of the foot, an uncommon and rare entity, accounts for <0.01% of all tuberculous localizations. Osteomyelitis secondary to tuberculosis is difficult to diagnose and treat, requiring a high suspicion index. We report a case of tuberculous osteomyelitis of the fifth metatarsal bone treated with the induced membrane technique. Here, we report the case of a 40-year-old woman with a history of immunosuppressive treatment presented with a complaint of painful swelling of the left foot. Radiographs showed osteolytic lesions of the fifth metatarsal bone. Initial biopsy suggested tuberculosis. She was surgically treated with the induced membrane technique. Histology confirmed tuberculous osteomyelitis and antituberculous treatment was initiated. Full weight-bearing was allowed after 8 months. At 24 months follow-up, all symptoms were resolved. The radiographs showed an integrated graft. In conclusion, the presence of osteolytic lesions on a plain film should rise high suspicious for a possible infection requiring biopsy, and if confirmed, mandates surgical debridement and reconstruction. The induced membrane technique offers a mean to treat infectious bone defects. Level of Evidence: Level 4.