As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially ...As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially in the context of an imbalance between osteoblast and osteoclast activities.Therefore,the development of new biomaterials has become the key.This article reviews various design strategies and their advantages and disadvantages for biomaterials aimed at osteoporotic bone defects.Overall,current research progress indicates that innovative design,functionalization,and targeting of materials can significantly enhance bone regeneration under osteoporotic conditions.By comprehensively considering biocompatibility,mechanical properties,and bioactivity,these biomaterials can be further optimized,offering a range of choices and strategies for the repair of osteoporotic bone defects.展开更多
BACKGROUND The induced-membrane technique was initially described by Masquelet as an effective treatment for large bone defects,especially those caused by infection.Here,we report a case of chronic osteomyelitis of th...BACKGROUND The induced-membrane technique was initially described by Masquelet as an effective treatment for large bone defects,especially those caused by infection.Here,we report a case of chronic osteomyelitis of the radius associated with a 9 cm bone defect,which was filled with a large allogeneic cortical bone graft from a bone bank.Complete bony union was achieved after 14 months of follow-up.Previous studies have used autogenous bone as the primary bone source for the Masquelet technique;in our case,the exclusive use of allografts is as successful as the use of autologous bone grafts.With the advent of bone banks,it is possible to obtain an unlimited amount of allograft,and the Masquelet technique may be further improved based on this new way of bone grafting.CASE SUMMARY In this study,we reported a case of repair of a long bone defect in a 40-year-old male patient,which was characterized by the utilization of allograft cortical bone combined with the Masquelet technique for the treatment of the patient's long bone defect in the forearm.The patient's results of functional recovery of the forearm were surprising,which further deepens the scope of application of Masquelet technique and helps to strengthen the efficacy of Masquelet technique in the treatment of long bones indeed.CONCLUSION Allograft cortical bone combined with the Masquelet technique provides a new method of treatment to large bone defect.展开更多
Large bone defects in load-bearing bone can result from tumor resection,osteomyelitis,trauma,and other factors.Although bone has the intrinsic potential to self-repair and regenerate,the repair of large bone defects w...Large bone defects in load-bearing bone can result from tumor resection,osteomyelitis,trauma,and other factors.Although bone has the intrinsic potential to self-repair and regenerate,the repair of large bone defects which exceed a certain critical size remains a substantial clinical challenge.Traditionally,repair methods involve using autologous or allogeneic bone tissue to replace the lost bone tissue at defect sites,and autogenous bone grafting remains the“gold standard”treatment.However,the application of traditional bone grafts is limited by drawbacks such as the quantity of extractable bone,donor-site morbidities,and the risk of rejection.In recent years,the clinical demand for alternatives to traditional bone grafts has promoted the development of novel bone-grafting substitutes.In addition to osteoconductivity and osteoinductivity,optimal mechanical properties have recently been the focus of efforts to improve the treatment success of novel bone-grafting alternatives in load-bearing bone defects,but most biomaterial synthetic scaffolds cannot provide sufficient mechanical strength.A fundamental challenge is to find an appropriate balance between mechanical and tissue-regeneration requirements.In this review,the use of traditional bone grafts in load-bearing bone defects,as well as their advantages and disadvantages,is summarized and reviewed.Furthermore,we highlight recent development strategies for novel bone grafts appropriate for load-bearing bone defects based on substance,structural,and functional bionics to provide ideas and directions for future research.展开更多
Infectious bone defects represent a substantial challenge in clinical practice,necessitating the deployment of advanced therapeutic strategies.This study presents a treatment modality that merges a mild photothermal t...Infectious bone defects represent a substantial challenge in clinical practice,necessitating the deployment of advanced therapeutic strategies.This study presents a treatment modality that merges a mild photothermal therapy hydrogel with a pulsed drug delivery mechanism.The system is predicated on a hydrogel matrix that is thermally responsive,characteristic of bone defect sites,facilitating controlled and site-specific drug release.The cornerstone of this system is the incorporation of mild photothermal nanoparticles,which are activated within the temperature range of 40–43°C,thereby enhancing the precision and efficacy of drug delivery.Our findings demonstrate that the photothermal response significantly augments the localized delivery of therapeutic agents,mitigating systemic side effects and bolstering efficacy at the defect site.The synchronized pulsed release,cooperated with mild photothermal therapy,effectively addresses infection control,and promotes bone regeneration.This approach signifies a considerable advancement in the management of infectious bone defects,offering an effective and patient-centric alternative to traditional methods.Our research endeavors to extend its applicability to a wider spectrum of tissue regeneration scenarios,underscoring its transformative potential in the realm of regenerative medicine.展开更多
The regeneration of infected bone defects is still challenging and time-consuming,due to the adverse osteogenic microenvironment caused by bacterial contamination and pronounced ischemia.Biodegradable magnesium(Mg)-ba...The regeneration of infected bone defects is still challenging and time-consuming,due to the adverse osteogenic microenvironment caused by bacterial contamination and pronounced ischemia.Biodegradable magnesium(Mg)-based alloys are desirable for orthopedic implants due to the mechanical properties approximating those of human bone and the released Mg^(2+)ions essential to osteogenic activity.However,the fast and uncontrolled self-degradation of Mg alloy,along with the inadequate antimicrobial activity,limit their strength in the osteogenic microenvironment.Inspired by the structural and physiological characteristics of“fish scales,”two-dimensional(2D)nanomaterials,black phosphorus(BP)and graphene oxide(GO),were assembled together under the action of pulsed electric field.The bionic 2D layered BP/GO nano-coating was constructed for infection resistance,osteogenic microenvironment optimization,and biodegradation control.In the early stage of implantation,it exerted a photothermal effect to ablate bacterial biofilms and avoid contaminating the microenvironment.The blocking effect of the“nano fish scales”-2D material superposition regulated the degradation of implants.In the later stage,it attracted the migration of vascular endothelial cells(VECs)and released phosphate slowly for in situ mineralization to create the microenvironment favoring vascularized bone formation.It is indicated that the enhancement of microtubule deacetylation and cytoskeletal reorganization played a key role in the effect of VEC migration and angiogenesis.This study provided a promising bionic strategy for creating osteogenic microenvironments that match the sequential healing process of infected bone defects.展开更多
The technology of three dimensional(3D) printing,also known as additive manufacturing,is a cuttingedge type of fabrication method that utilizes a computer-aided design platform and employs layer-bylayer stacking to co...The technology of three dimensional(3D) printing,also known as additive manufacturing,is a cuttingedge type of fabrication method that utilizes a computer-aided design platform and employs layer-bylayer stacking to construct objects with exceptional flexibility.Due to its capacity to produce a substantial quantity of products within a short period of time,3D printing has emerged as one of the most significant manufacturing technology.Over the past two decades,remarkable advancements have been made in the application of 3D printing technology in the realm of bone tissue engineering.This review presents an innovative and systematic discussion on the potential application of 3D printing technology in bone tissue engineering,particularly in the treatment of infected bone defects.It comprehensively evaluates the materials utilized in 3D printing,highlights the interplay between cells and bone regeneration,and addresses and resolves challenges associated with current 3D printing technology.These challenges include material selection,fabrication of intricate 3D structures,integration of different cell types,streamlining design processes and material selection procedures,enhancing the clinical translational potential of 3D printing technology,and ultimately exploring future applications of four dimensional(4D) printing technology.The 3D printing technology has demonstrated significant potential in the synthesis of bone substitutes,offering consistent mechanical properties and ease of use.It has found extensive applications in personalized implant customization,prosthetic limb manufacturing,surgical tool production,tissue engineering,biological modeling,and cell diagnostics.Simultaneously,3D bioprinting provides an effective solution to address the issue of organ donor shortage.However,challenges still exist in material selection,management of structural complexity,integration of different cell types,and construction of functionally mature tissues.With advancements in multi-material printing techniques as well as bioprinting and 4D printing technologies emerging on the horizon;3D printing holds immense prospects for revolutionizing the means by which infectious bone defects are repaired.展开更多
Management of post-traumatic long-bone defects remains relevant and cha-llenging despite the rapid development of approaches to their treatment.Do-minant positions are occupied by the Ilizarov method,bone autogenous g...Management of post-traumatic long-bone defects remains relevant and cha-llenging despite the rapid development of approaches to their treatment.Do-minant positions are occupied by the Ilizarov method,bone autogenous grafting and the Masquelet induced membrane technique(IMT).The IMT is aimed at reducing extensive defect treatment duration and for this reason has gained great popularity.However,the assessment of its effectiveness is difficult due to a limited number of clinical series.The varying clinical manifestations of bone defect severity do not allow a comprehensive evaluation of IMT effectiveness.One of them is infection in the defect area.The purpose of our literature review is an analysis of studies on IMT application in infected vs non-infected long-bone defects of the lower extremities published over the last 10 years.It focuses on the investigation of similarities and fundamental differences in the need for antibiotics,timing of spacer fixation,methods of collecting donor bone and fixators used for consolidation.The studies show that the IMT has been globally used in aseptic and osteomyelitic defects due to its clinical effectiveness.Authors’variations and improvements in its practical implementation indicate the ongoing development and the interest of researchers in this technique.展开更多
Objective:We aim to develop a dual-functional bone regeneration scaffold(Qx-D)with antibacterial and osteogenic properties for infected bone defect treatment.Impact Statement:This study provides insights into antibact...Objective:We aim to develop a dual-functional bone regeneration scaffold(Qx-D)with antibacterial and osteogenic properties for infected bone defect treatment.Impact Statement:This study provides insights into antibacterial components that could be combined with naturally derived materials through a facile Schiff base reaction,offering a potential strategy to enhance antibacterial properties.Introduction:Naturally derived decalcified bone matrix(DBM)has been reported to be porous and biodegradable.DBM can induce various cell differentiations and participate in immune regulation,making it an ideal bone regeneration scaffold for bone defects.However,DBM does not exhibit antimicrobial properties.Therefore,it is essential to develop antibacterial functionalization method for DBM.Methods:DBM was modified with a macromolecular quaternary ammonium salt(QPEI).A series of Qx-D with tunable feeding ratios were synthesized through Schiff base reaction.The morphology,chemical property,in vitro antibacterial efficiency,in vitro biocompatibility,osteogenic property,and in vivo anti-infection performances were characterized.Results:All Qx-D exhibited marked antibacterial properties.Small adjustments in feed concentration could not induce changes in antibacterial properties.However,cell viability slightly decreased with increasing feed concentration.Q10-D demonstrated significant antibacterial properties and could promote recovery of infected bone defect in an animal model.Conclusion:Qx-D shows marked antibacterial properties and good biocompatibility.Moreover,Q10-D could be a potential choice for infected bone defects.展开更多
Additive manufacturing(AM)has revolutionized the design and manufacturing of patient-specific,three-dimensional(3D),complex porous structures known as scaffolds for tissue engineering applications.The use of advanced ...Additive manufacturing(AM)has revolutionized the design and manufacturing of patient-specific,three-dimensional(3D),complex porous structures known as scaffolds for tissue engineering applications.The use of advanced image acquisition techniques,image processing,and computer-aided design methods has enabled the precise design and additive manufacturing of anatomically correct and patient-specific implants and scaffolds.However,these sophisticated techniques can be timeconsuming,labor-intensive,and expensive.Moreover,the necessary imaging and manufacturing equipment may not be readily available when urgent treatment is needed for trauma patients.In this study,a novel design and AM methods are proposed for the development of modular and customizable scaffold blocks that can be adapted to fit the bone defect area of a patient.These modular scaffold blocks can be combined to quickly form any patient-specific scaffold directly from two-dimensional(2D)medical images when the surgeon lacks access to a 3D printer or cannot wait for lengthy 3D imaging,modeling,and 3D printing during surgery.The proposed method begins with developing a bone surface-modeling algorithm that reconstructs a model of the patient’s bone from 2D medical image measurements without the need for expensive 3D medical imaging or segmentation.This algorithm can generate both patient-specific and average bone models.Additionally,a biomimetic continuous path planning method is developed for the additive manufacturing of scaffolds,allowing porous scaffold blocks with the desired biomechanical properties to be manufactured directly from 2D data or images.The algorithms are implemented,and the designed scaffold blocks are 3D printed using an extrusion-based AM process.Guidelines and instructions are also provided to assist surgeons in assembling scaffold blocks for the self-repair of patient-specific large bone defects.展开更多
Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.M...Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.Methods:From July 2023 to April 2024,80 patients with upper anterior tooth loss and labial bone defects were admitted to the hospital and selected as evaluation samples.They were divided into an observation group(n=40)and a control group(n=40)using a numerical table lottery scheme.The control group received treatment with the GBR technique,while the observation group received treatment with the GBR technique combined with temporary bridges to guide gingival contouring.The two groups were compared in terms of clinical red aesthetic scores(PES),labial alveolar bone density,labial bone wall thickness,gingival papillae,gingival margin levels,and patient satisfaction.Results:The PES scores of patients in the observation group were higher than those in the control group after surgery(P<0.05).The bone density of the labial alveolar bone and the thickness of the labial bone wall in the observation group were higher than those in the control group.The levels of gingival papillae and gingival margins were lower in the observation group after surgery(P<0.05).Additionally,patient satisfaction in the observation group was higher than in the control group(P<0.05).Conclusion:The GBR technique combined with temporary bridge-guided gingival contouring for treating upper anterior tooth loss with labial bone defects can improve the aesthetic effect of gingival soft tissue,increase alveolar bone density and the thickness of the labial bone wall,and enhance patient satisfaction.This approach is suitable for widespread application in healthcare institutions.展开更多
Objective:To explore the clinical value of autologous skull transplantation in the treatment of skull defects.Methods:Sixty-six patients who underwent skull defect reconstruction treatment in our hospital from January...Objective:To explore the clinical value of autologous skull transplantation in the treatment of skull defects.Methods:Sixty-six patients who underwent skull defect reconstruction treatment in our hospital from January 2022 to March 2024 were selected and divided into an autologous skull transplantation group(n=31)and an artificial bone transplantation material group(n=35)based on different bone transplantation materials.The two groups of patients were followed up for 12 months to observe the bone healing and the incidence of postoperative complications.Results:After 9 months of treatment,the bone healing performance of the autologous skull transplantation group was better than that of the artificial bone transplantation material group(P<0.05).By the end of the last follow-up,the incidence of bony postoperative complications in the autologous skull transplantation group was lower than that in the artificial bone transplantation material group(P<0.05).Conclusion:Autologous skull repair for skull defects has good biocompatibility,can promote bone healing,and reduce the incidence of postoperative complications.展开更多
In clinical settings,regenerating critical-sized calvarial bone defects presents substantial problems owing to the intricacy of surgical methods,restricted bone growth medications,and a scarcity of commercial bone gra...In clinical settings,regenerating critical-sized calvarial bone defects presents substantial problems owing to the intricacy of surgical methods,restricted bone growth medications,and a scarcity of commercial bone grafts.To treat this life-threatening issue,improved biofunctional grafts capable of properly healing critical-sized bone defects are required.In this study,we effectively created anti-fracture hydrogel systems using spongy-like metal-organic(magnesium-phosphate)coordinated chitosan-modified injectable hydrogels(CPMg)loaded with a bioinspired neobavaisoflavone(NBF)component.The CPMg-NBF hydrogels showed outstanding anti-fracture capabilities during compression testing and retained exceptional mechanical stability even after 28 d of immersion in phosphatebuffered saline.They also demonstrated prolonged and stable release profiles of Mg^(2+)and NBF.Importantly,CPMg-NBF hydrogels revealed robust biphasic mineralization and were non-toxic to MC3T3-E1 cells.To better understand the underlying mechanism of Mg^(2+)and NBF component,as well as their synergistic effect on osteogenesis,we investigated the expression of key osteogenic proteins in the p38 MAPK and NOTCH pathways.Our results showed that CPMg-NBF hydrogels greatly increased the expression of osteogenic proteins(Runx2,OCN,OPN,BMPS and ALP).In vivo experiments showed that the implantation of CPMg-NBF hydrogels resulted in a significant increase in new bone growth within critical-sized calvarial defects.Based on these findings,we expect that the CPMg-NBF supramolecular hydrogel has tremendous promise for use as a therapeutic biomaterial for treating critical-sized calvarial defects.展开更多
Additive manufacturing(AM)has revolutionized the production of metal bone implants,enabling unprecedented levels of customization and functionality.Recent advancements in surface-modification technologies have been cr...Additive manufacturing(AM)has revolutionized the production of metal bone implants,enabling unprecedented levels of customization and functionality.Recent advancements in surface-modification technologies have been crucial in enhancing the performance and biocompatibility of implants.Through leveraging the versatility of AM techniques,particularly powder bed fusion,a range of metallic biomaterials,including stainless steel,titanium,and biodegradable alloys,can be utilized to fabricate implants tailored for craniofacial,trunk,and limb bone reconstructions.However,the potential of AM is contingent on addressing intrinsic defects that may hinder implant performance.Techniques such as sandblasting,chemical treatment,electropolishing,heat treatment,and laser technology effectively remove residual powder and improve the surface roughness of these implants.The development of functional coatings,applied via both dry and wet methods,represents a significant advancement in surface modification research.These coatings not only improve mechanical and biological interactions at the implant-bone interface but also facilitate controlled drug release and enhance antimicrobial properties.Addition-ally,micro-and nanoscale surface modifications using chemical and laser techniques can precisely sculpt implant surfaces to promote the desired cellular responses.This detailed exploration of surface engineering offers a wealth of opportunities for creating next-generation implants that are not only biocompatible but also bioactive,laying the foundation for more effective solutions in bone reconstruction.展开更多
Bone repair remains an important target in tissue engineering,making the development of bioactive scaffolds for effective bone defect repair a critical objective.In this study,β-tricalcium phosphate(β-TCP)scaffolds ...Bone repair remains an important target in tissue engineering,making the development of bioactive scaffolds for effective bone defect repair a critical objective.In this study,β-tricalcium phosphate(β-TCP)scaffolds incorporated with processed pyritum decoction(PPD)were fabricated using three-dimensional(3D)printing-assisted freeze-casting.The produced composite scaffolds were evaluated for their mechanical strength,physicochemical properties,biocompatibility,in vitro proangiogenic activity,and in vivo efficacy in repairing rabbit femoral defects.They not only demonstrated excellent physicochemical properties,enhanced mechanical strength,and good biosafety but also significantly promoted the proliferation,migration,and aggregation of pro-angiogenic human umbilical vein endothelial cells(HUVECs).In vivo studies revealed that all scaffold groups facilitated osteogenesis at the bone defect site,with theβ-TCP scaffolds loaded with PPD markedly enhancing the expression of neurogenic locus Notch homolog protein 1(Notch1),vascular endothelial growth factor(VEGF),bone morphogenetic protein-2(BMP-2),and osteopontin(OPN).Overall,the scaffolds developed in this study exhibited strong angiogenic and osteogenic capabilities both in vitro and in vivo.The incorporation of PPD notably promoted the angiogenic-osteogenic coupling,thereby accelerating bone repair,which suggests that PPD is a promising material for bone repair and that the PPD/β-TCP scaffolds hold great potential as a bone graft alternative.展开更多
Reconstruction of a traumatic distal femur defect remains a therapeutic challenge.Bone defect implants have been proposed to substitute the bone defect,and their biomechanical performances can be analyzed via a numeri...Reconstruction of a traumatic distal femur defect remains a therapeutic challenge.Bone defect implants have been proposed to substitute the bone defect,and their biomechanical performances can be analyzed via a numerical approach.However,the material assumptions for past computational human femur simulations were mainly homogeneous.Thus,this study aimed to design and analyze scaffolds for reconstructing the distal femur defect using a patient-specific finite element modeling technique.A three-dimensional finite element model of the human femur with accurate geometry and material distribution was developed using the finite element method and material mapping technique.An intact femur and a distal femur defect model treated with nine microstructure scaffolds and two solid scaffolds were investigated and compared under a single-leg stance loading.The results showed that the metal solid scaffold design could provide the most stable fixation for reconstructing the distal femur defect.However,the fixation stability was affected by various microstructure designs and pillar diameters.A microstructure scaffold can be designed to satisfy all the biomechanical indexes,opening up future possibilities for more stable reconstructions.A three-dimensional finite element model of the femur with real bone geometry and bone material distribution can be developed,and this patient-specific femur model can be used for studying other femoral fractures or injuries,paving the way for more comprehensive research in the field.Besides,this patient-specific finite element modeling technique can also be applied to developing other human or animal bone models,expanding the scope of biomechanical research.展开更多
Osteogenesis imperfecta(OI)is a group of diseases caused by defects in type I collagen processing which result in skeletal fragility.While these disorders have been regarded as defects in osteoblast function,the role ...Osteogenesis imperfecta(OI)is a group of diseases caused by defects in type I collagen processing which result in skeletal fragility.While these disorders have been regarded as defects in osteoblast function,the role of matrix-embedded osteocytes in OI pathogenesis remains largely unknown.Homozygous human SP7(c.946 C>T,R316C)mutation results in a recessive form of OI characterized by fragility fractures,low bone mineral density and osteocyte dendrite defects.To better understand how the OI-causing R316C mutation affects the function of SP7,we generated Sp7^(R342C)knock-in mice.Consistent with patient phenotypes,Sp7^(R342C/R342C)mice demonstrate increased cortical porosity and reduced cortical bone mineral density.Sp7^(R342C/R342C)mice show osteocyte dendrite defects,increased osteocyte apoptosis,and intracortical bone remodeling with ectopic intracortical osteoclasts and elevated osteocyte Tnfsf11 expression.展开更多
This study aimed to utilize micro-computed tomography （micro-CT） analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite （CFB-HAP） or collagen （Bio-Gide） membranes. ...This study aimed to utilize micro-computed tomography （micro-CT） analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite （CFB-HAP） or collagen （Bio-Gide） membranes. Fifty-four （54） rats were studied. A circular bony defect （8 mm diameter） was formed in the centre of the calvaria using a trephine bur. The CFB-HAP membrane was prepared by thermally induced phase separation. In the experimental group （n= 18）, the CFB-HAP membrane was used to cover the bony defect, and in the control group （n= 18）, a resorbable collagen membrane （Bio-Gide） was used. In the negative control group （n= 18）, no membrane was used. In each group, six animals were euthanized at 2, 4 and 8 weeks after surgery. The specimens were then analysed using micro-CT. There were significant differences in bone volume （BV） and bone mineral density （BMD） （P〈O.05） between the negative control group and the membrane groups. However, there were no significant differences between the CFB-HAP group and the collagen group. We concluded that the CFB-HAP membrane has significant potential as a guided bone regeneration （GBR） membrane.展开更多
We hypothesized that a chemically extracted acellular allogeneic nerve graft used in combination with bone marrow mesenchymal stem cell transplantation would be an effective treatment for long-segment sciatic nerve de...We hypothesized that a chemically extracted acellular allogeneic nerve graft used in combination with bone marrow mesenchymal stem cell transplantation would be an effective treatment for long-segment sciatic nerve defects.To test this,we established rabbit models of 30 mm sciatic nerve defects,and treated them using either an autograft or a chemically decellularized allogeneic nerve graft with or without simultaneous transplantation of bone marrow mesenchymal stem cells.We compared the tensile properties,electrophysiological function and morphology of the damaged nerve in each group.Sciatic nerves repaired by the allogeneic nerve graft combined with stem cell transplantation showed better recovery than those repaired by the acellular allogeneic nerve graft alone,and produced similar results to those observed with the autograft.These findings confirm that a chemically extracted acellular allogeneic nerve graft combined with transplantation of bone marrow mesenchymal stem cells is an effective method of repairing long-segment sciatic nerve defects.展开更多
BACKGROUND Ilizarov non-free bone plasty is a method of distraction osteogenesis using the Ilizarov apparatus for external fixation which originated in Russia and was disseminated across the world. It has been used in...BACKGROUND Ilizarov non-free bone plasty is a method of distraction osteogenesis using the Ilizarov apparatus for external fixation which originated in Russia and was disseminated across the world. It has been used in long bone defect and nonunion management along with free vascularized grafting and induced membrane technique. However, the shortcomings and problems of these methods still remain the issues which restrict their overall use.AIM To study the recent available literature on the role of Ilizarov non-free bone plasty in long bone defect and nonunion management, its problems and the solutions to these problems in order to achieve better treatment outcomes.METHODS Three databases(Pub Med, Scopus, and Web of Science) were searched for literature sources on distraction osteogenesis, free vascularized grafting and induced membrane technique used in long bone defect and nonunion treatment within a five-year period(2015-2019). Full-text clinical articles in the English language were selected for analysis only if they contained treatment results,complications and described large patient samples(not less than ten cases for congenital, post-tumor resection cases or rare conditions, and more than 20 cases for the rest). Case reports were excluded.RESULTS Fifty full-text articles and reviews on distraction osteogenesis were chosen.Thirty-five clinical studies containing large series of patients treated with this method and problems with its outcome were analyzed. It was found that distraction osteogenesis techniques provide treatment for segmental bone defects and nonunion of the lower extremity in many clinical situations, especially in complex problems. The Ilizarov techniques treat the triad of problems simultaneously(bone loss, soft-tissue loss and infection). Management of tibial defects mostly utilizes the Ilizarov circular fixator. Monolateral fixators are preferable in the femur. The use of a ring fixator is recommended in patients with an infected tibial bone gap of more than 6 cm. High rates of successful treatment were reported by the authors that ranged from 77% to 100% and depended on the pathology and the type of Ilizarov technique used. Hybrid fixation and autogenous grafting are the most applicable solutions to avoid after-frame regenerate fracture or deformity and docking site nonunion.CONCLUSION The role of Ilizarov non-free bone plasty has not lost its significance in the treatment of segmental bone defects despite the shortcomings and treatment problems encountered.展开更多
The aim of the present real time in vivo micro-computed tomography （pCT） and histologic experiment was to assess the efficacy of guided bone regeneration （GBR） around standardized calvarial critical size defects ...The aim of the present real time in vivo micro-computed tomography （pCT） and histologic experiment was to assess the efficacy of guided bone regeneration （GBR） around standardized calvarial critical size defects （CSD） using bone marrow-derived mesenchymal stem cells （BMSCs）, and collagen membrane （CM） with and without tricalcium phosphate （TCP） graft material. In the calvaria of nine female Sprague-Dawley rats, full-thickness CSD （diameter 4.6 mm） were created under general anesthesia. Treatment-wise, rats were divided into three groups. In group 1, CSD was covered with a resorbable CM; in group 2, BMSCs were filled in CSD and covered with CM; and in group 3, TCP soaked in BMSCs was placed in CSD and covered with CM. All defects were closed using resorbable sutures. Bone volume and bone mineral density of newly formed bone （NFB） and remaining TCP particles and rate of new bone formation was determined at baseline, 2, 4, 6, and 10 weeks using in vivo pCT. At the lOth week, the rats were killed and calvarial segments were assessed histologically. The results showed that the hardness of NFB was similar to that of the native bone in groups I and 2 as compared to the NFB in group 3. Likewise, values for the modulus of elasticity were also significantly higher in group 3 compared to groups 1 and 2. This suggests that TCP when used in combination with BMSCs and without CM was unable to form bone of significant strength that could possibly provide mechanical ＂lock＂ between the natural bone and NFB. The use of BMSCs as adjuncts to conventional GBR initiated new bone formation as early as 2 weeks of treatment compared to when GBR is attempted without adiunct BMSC therapy.展开更多
基金supported by the National Natural Science Foundation of China(Nos.82160419 and 82302772)Guizhou Basic Research Project(No.ZK[2023]General 201)。
文摘As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially in the context of an imbalance between osteoblast and osteoclast activities.Therefore,the development of new biomaterials has become the key.This article reviews various design strategies and their advantages and disadvantages for biomaterials aimed at osteoporotic bone defects.Overall,current research progress indicates that innovative design,functionalization,and targeting of materials can significantly enhance bone regeneration under osteoporotic conditions.By comprehensively considering biocompatibility,mechanical properties,and bioactivity,these biomaterials can be further optimized,offering a range of choices and strategies for the repair of osteoporotic bone defects.
文摘BACKGROUND The induced-membrane technique was initially described by Masquelet as an effective treatment for large bone defects,especially those caused by infection.Here,we report a case of chronic osteomyelitis of the radius associated with a 9 cm bone defect,which was filled with a large allogeneic cortical bone graft from a bone bank.Complete bony union was achieved after 14 months of follow-up.Previous studies have used autogenous bone as the primary bone source for the Masquelet technique;in our case,the exclusive use of allografts is as successful as the use of autologous bone grafts.With the advent of bone banks,it is possible to obtain an unlimited amount of allograft,and the Masquelet technique may be further improved based on this new way of bone grafting.CASE SUMMARY In this study,we reported a case of repair of a long bone defect in a 40-year-old male patient,which was characterized by the utilization of allograft cortical bone combined with the Masquelet technique for the treatment of the patient's long bone defect in the forearm.The patient's results of functional recovery of the forearm were surprising,which further deepens the scope of application of Masquelet technique and helps to strengthen the efficacy of Masquelet technique in the treatment of long bones indeed.CONCLUSION Allograft cortical bone combined with the Masquelet technique provides a new method of treatment to large bone defect.
基金supported by the National Natural Science Foundation of China(No.82202450).
文摘Large bone defects in load-bearing bone can result from tumor resection,osteomyelitis,trauma,and other factors.Although bone has the intrinsic potential to self-repair and regenerate,the repair of large bone defects which exceed a certain critical size remains a substantial clinical challenge.Traditionally,repair methods involve using autologous or allogeneic bone tissue to replace the lost bone tissue at defect sites,and autogenous bone grafting remains the“gold standard”treatment.However,the application of traditional bone grafts is limited by drawbacks such as the quantity of extractable bone,donor-site morbidities,and the risk of rejection.In recent years,the clinical demand for alternatives to traditional bone grafts has promoted the development of novel bone-grafting substitutes.In addition to osteoconductivity and osteoinductivity,optimal mechanical properties have recently been the focus of efforts to improve the treatment success of novel bone-grafting alternatives in load-bearing bone defects,but most biomaterial synthetic scaffolds cannot provide sufficient mechanical strength.A fundamental challenge is to find an appropriate balance between mechanical and tissue-regeneration requirements.In this review,the use of traditional bone grafts in load-bearing bone defects,as well as their advantages and disadvantages,is summarized and reviewed.Furthermore,we highlight recent development strategies for novel bone grafts appropriate for load-bearing bone defects based on substance,structural,and functional bionics to provide ideas and directions for future research.
基金supported by the National Natural Science Foundation of China(32171354,82222015,82171001)The National Key Research and Development Program of China2023YFC2413600Research Funding from West China School/Hospital of Stomatology,Sichuan University(No.RCDWIS2023-1).
文摘Infectious bone defects represent a substantial challenge in clinical practice,necessitating the deployment of advanced therapeutic strategies.This study presents a treatment modality that merges a mild photothermal therapy hydrogel with a pulsed drug delivery mechanism.The system is predicated on a hydrogel matrix that is thermally responsive,characteristic of bone defect sites,facilitating controlled and site-specific drug release.The cornerstone of this system is the incorporation of mild photothermal nanoparticles,which are activated within the temperature range of 40–43°C,thereby enhancing the precision and efficacy of drug delivery.Our findings demonstrate that the photothermal response significantly augments the localized delivery of therapeutic agents,mitigating systemic side effects and bolstering efficacy at the defect site.The synchronized pulsed release,cooperated with mild photothermal therapy,effectively addresses infection control,and promotes bone regeneration.This approach signifies a considerable advancement in the management of infectious bone defects,offering an effective and patient-centric alternative to traditional methods.Our research endeavors to extend its applicability to a wider spectrum of tissue regeneration scenarios,underscoring its transformative potential in the realm of regenerative medicine.
基金supported by the National Natural Science Foundation of China[81801007]the Traditional Chinese Medicine Bureau of Guangdong Province[20242062]+2 种基金the Major of Basic and Applied Basic Research Project of Guangzhou City[202201011601]the Science and Cultivation Foundation of Stomatological Hospital of Southern Medical University[PY2021016]the Guangdong Province Clinical Teaching Base Teaching Reform Research Project[2023JD054].
文摘The regeneration of infected bone defects is still challenging and time-consuming,due to the adverse osteogenic microenvironment caused by bacterial contamination and pronounced ischemia.Biodegradable magnesium(Mg)-based alloys are desirable for orthopedic implants due to the mechanical properties approximating those of human bone and the released Mg^(2+)ions essential to osteogenic activity.However,the fast and uncontrolled self-degradation of Mg alloy,along with the inadequate antimicrobial activity,limit their strength in the osteogenic microenvironment.Inspired by the structural and physiological characteristics of“fish scales,”two-dimensional(2D)nanomaterials,black phosphorus(BP)and graphene oxide(GO),were assembled together under the action of pulsed electric field.The bionic 2D layered BP/GO nano-coating was constructed for infection resistance,osteogenic microenvironment optimization,and biodegradation control.In the early stage of implantation,it exerted a photothermal effect to ablate bacterial biofilms and avoid contaminating the microenvironment.The blocking effect of the“nano fish scales”-2D material superposition regulated the degradation of implants.In the later stage,it attracted the migration of vascular endothelial cells(VECs)and released phosphate slowly for in situ mineralization to create the microenvironment favoring vascularized bone formation.It is indicated that the enhancement of microtubule deacetylation and cytoskeletal reorganization played a key role in the effect of VEC migration and angiogenesis.This study provided a promising bionic strategy for creating osteogenic microenvironments that match the sequential healing process of infected bone defects.
基金supported by the National Natural Science Fund of China(Nos.82202726,82370929)the National Clinical Research Center for Geriatrics,West China Hospital,Sichuan University(No.Z20192013)+5 种基金Key research and development project of Sichuan Science and Technology Department(No.2023YFG0219)"Zeroto One" Innovation Research Project of Sichuan University(No.2022SCUH0014)Frontiers Medical Center,Tianfu Jincheng Laboratory Foundation(No.TFJC2023010001)Sichuan Science and Technology Program(No.2022NSFSC0002)Sichuan Province Youth Science and Technology Innovation Team(No.2022JDTD0021)Research and Develop Program,West China Hospital of Stomatology Sichuan University(Nos.RD03202302,RCDWJS2024-1)。
文摘The technology of three dimensional(3D) printing,also known as additive manufacturing,is a cuttingedge type of fabrication method that utilizes a computer-aided design platform and employs layer-bylayer stacking to construct objects with exceptional flexibility.Due to its capacity to produce a substantial quantity of products within a short period of time,3D printing has emerged as one of the most significant manufacturing technology.Over the past two decades,remarkable advancements have been made in the application of 3D printing technology in the realm of bone tissue engineering.This review presents an innovative and systematic discussion on the potential application of 3D printing technology in bone tissue engineering,particularly in the treatment of infected bone defects.It comprehensively evaluates the materials utilized in 3D printing,highlights the interplay between cells and bone regeneration,and addresses and resolves challenges associated with current 3D printing technology.These challenges include material selection,fabrication of intricate 3D structures,integration of different cell types,streamlining design processes and material selection procedures,enhancing the clinical translational potential of 3D printing technology,and ultimately exploring future applications of four dimensional(4D) printing technology.The 3D printing technology has demonstrated significant potential in the synthesis of bone substitutes,offering consistent mechanical properties and ease of use.It has found extensive applications in personalized implant customization,prosthetic limb manufacturing,surgical tool production,tissue engineering,biological modeling,and cell diagnostics.Simultaneously,3D bioprinting provides an effective solution to address the issue of organ donor shortage.However,challenges still exist in material selection,management of structural complexity,integration of different cell types,and construction of functionally mature tissues.With advancements in multi-material printing techniques as well as bioprinting and 4D printing technologies emerging on the horizon;3D printing holds immense prospects for revolutionizing the means by which infectious bone defects are repaired.
文摘Management of post-traumatic long-bone defects remains relevant and cha-llenging despite the rapid development of approaches to their treatment.Do-minant positions are occupied by the Ilizarov method,bone autogenous grafting and the Masquelet induced membrane technique(IMT).The IMT is aimed at reducing extensive defect treatment duration and for this reason has gained great popularity.However,the assessment of its effectiveness is difficult due to a limited number of clinical series.The varying clinical manifestations of bone defect severity do not allow a comprehensive evaluation of IMT effectiveness.One of them is infection in the defect area.The purpose of our literature review is an analysis of studies on IMT application in infected vs non-infected long-bone defects of the lower extremities published over the last 10 years.It focuses on the investigation of similarities and fundamental differences in the need for antibiotics,timing of spacer fixation,methods of collecting donor bone and fixators used for consolidation.The studies show that the IMT has been globally used in aseptic and osteomyelitic defects due to its clinical effectiveness.Authors’variations and improvements in its practical implementation indicate the ongoing development and the interest of researchers in this technique.
基金supported by the National Natural Science Foundation of China(grant nos.52122304,52293382,52221006,and 52073024)the Beijing Municipal Administration of Hospitals Incubating Program(grant no.PX2021005).
文摘Objective:We aim to develop a dual-functional bone regeneration scaffold(Qx-D)with antibacterial and osteogenic properties for infected bone defect treatment.Impact Statement:This study provides insights into antibacterial components that could be combined with naturally derived materials through a facile Schiff base reaction,offering a potential strategy to enhance antibacterial properties.Introduction:Naturally derived decalcified bone matrix(DBM)has been reported to be porous and biodegradable.DBM can induce various cell differentiations and participate in immune regulation,making it an ideal bone regeneration scaffold for bone defects.However,DBM does not exhibit antimicrobial properties.Therefore,it is essential to develop antibacterial functionalization method for DBM.Methods:DBM was modified with a macromolecular quaternary ammonium salt(QPEI).A series of Qx-D with tunable feeding ratios were synthesized through Schiff base reaction.The morphology,chemical property,in vitro antibacterial efficiency,in vitro biocompatibility,osteogenic property,and in vivo anti-infection performances were characterized.Results:All Qx-D exhibited marked antibacterial properties.Small adjustments in feed concentration could not induce changes in antibacterial properties.However,cell viability slightly decreased with increasing feed concentration.Q10-D demonstrated significant antibacterial properties and could promote recovery of infected bone defect in an animal model.Conclusion:Qx-D shows marked antibacterial properties and good biocompatibility.Moreover,Q10-D could be a potential choice for infected bone defects.
文摘Additive manufacturing(AM)has revolutionized the design and manufacturing of patient-specific,three-dimensional(3D),complex porous structures known as scaffolds for tissue engineering applications.The use of advanced image acquisition techniques,image processing,and computer-aided design methods has enabled the precise design and additive manufacturing of anatomically correct and patient-specific implants and scaffolds.However,these sophisticated techniques can be timeconsuming,labor-intensive,and expensive.Moreover,the necessary imaging and manufacturing equipment may not be readily available when urgent treatment is needed for trauma patients.In this study,a novel design and AM methods are proposed for the development of modular and customizable scaffold blocks that can be adapted to fit the bone defect area of a patient.These modular scaffold blocks can be combined to quickly form any patient-specific scaffold directly from two-dimensional(2D)medical images when the surgeon lacks access to a 3D printer or cannot wait for lengthy 3D imaging,modeling,and 3D printing during surgery.The proposed method begins with developing a bone surface-modeling algorithm that reconstructs a model of the patient’s bone from 2D medical image measurements without the need for expensive 3D medical imaging or segmentation.This algorithm can generate both patient-specific and average bone models.Additionally,a biomimetic continuous path planning method is developed for the additive manufacturing of scaffolds,allowing porous scaffold blocks with the desired biomechanical properties to be manufactured directly from 2D data or images.The algorithms are implemented,and the designed scaffold blocks are 3D printed using an extrusion-based AM process.Guidelines and instructions are also provided to assist surgeons in assembling scaffold blocks for the self-repair of patient-specific large bone defects.
文摘Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.Methods:From July 2023 to April 2024,80 patients with upper anterior tooth loss and labial bone defects were admitted to the hospital and selected as evaluation samples.They were divided into an observation group(n=40)and a control group(n=40)using a numerical table lottery scheme.The control group received treatment with the GBR technique,while the observation group received treatment with the GBR technique combined with temporary bridges to guide gingival contouring.The two groups were compared in terms of clinical red aesthetic scores(PES),labial alveolar bone density,labial bone wall thickness,gingival papillae,gingival margin levels,and patient satisfaction.Results:The PES scores of patients in the observation group were higher than those in the control group after surgery(P<0.05).The bone density of the labial alveolar bone and the thickness of the labial bone wall in the observation group were higher than those in the control group.The levels of gingival papillae and gingival margins were lower in the observation group after surgery(P<0.05).Additionally,patient satisfaction in the observation group was higher than in the control group(P<0.05).Conclusion:The GBR technique combined with temporary bridge-guided gingival contouring for treating upper anterior tooth loss with labial bone defects can improve the aesthetic effect of gingival soft tissue,increase alveolar bone density and the thickness of the labial bone wall,and enhance patient satisfaction.This approach is suitable for widespread application in healthcare institutions.
文摘Objective:To explore the clinical value of autologous skull transplantation in the treatment of skull defects.Methods:Sixty-six patients who underwent skull defect reconstruction treatment in our hospital from January 2022 to March 2024 were selected and divided into an autologous skull transplantation group(n=31)and an artificial bone transplantation material group(n=35)based on different bone transplantation materials.The two groups of patients were followed up for 12 months to observe the bone healing and the incidence of postoperative complications.Results:After 9 months of treatment,the bone healing performance of the autologous skull transplantation group was better than that of the artificial bone transplantation material group(P<0.05).By the end of the last follow-up,the incidence of bony postoperative complications in the autologous skull transplantation group was lower than that in the artificial bone transplantation material group(P<0.05).Conclusion:Autologous skull repair for skull defects has good biocompatibility,can promote bone healing,and reduce the incidence of postoperative complications.
基金supported by Natural Science Foundation of China(No.82202664,82172432,U22A20371)Shenzhen Sustainable Development Project(No.KCXFZ20201221173411031)+4 种基金Shenzhen Science and Technology Program(JCYJ20220818102815033,National Science Foundation of Guangdong Province(No.2021A1515220053,2022A1515010034,2021B1515120061)Guangdong Basic and Applied Basic Research Foundation(No.2019A1515110983,2022A1515012663)Guangzhou Basic and Applied Basic Research Foundation(202102021160)the Fundamental Research Funds for the Central Universities(21624221)the Research Fund Program of Guangdong Provincial Key Laboratory of Speed Capability Research(2023B1212010009).
文摘In clinical settings,regenerating critical-sized calvarial bone defects presents substantial problems owing to the intricacy of surgical methods,restricted bone growth medications,and a scarcity of commercial bone grafts.To treat this life-threatening issue,improved biofunctional grafts capable of properly healing critical-sized bone defects are required.In this study,we effectively created anti-fracture hydrogel systems using spongy-like metal-organic(magnesium-phosphate)coordinated chitosan-modified injectable hydrogels(CPMg)loaded with a bioinspired neobavaisoflavone(NBF)component.The CPMg-NBF hydrogels showed outstanding anti-fracture capabilities during compression testing and retained exceptional mechanical stability even after 28 d of immersion in phosphatebuffered saline.They also demonstrated prolonged and stable release profiles of Mg^(2+)and NBF.Importantly,CPMg-NBF hydrogels revealed robust biphasic mineralization and were non-toxic to MC3T3-E1 cells.To better understand the underlying mechanism of Mg^(2+)and NBF component,as well as their synergistic effect on osteogenesis,we investigated the expression of key osteogenic proteins in the p38 MAPK and NOTCH pathways.Our results showed that CPMg-NBF hydrogels greatly increased the expression of osteogenic proteins(Runx2,OCN,OPN,BMPS and ALP).In vivo experiments showed that the implantation of CPMg-NBF hydrogels resulted in a significant increase in new bone growth within critical-sized calvarial defects.Based on these findings,we expect that the CPMg-NBF supramolecular hydrogel has tremendous promise for use as a therapeutic biomaterial for treating critical-sized calvarial defects.
基金supported by National Natural Science Foundation of China(Grant No.52275343)Natural Science Foundation of Zhejiang Province(Grant No.LY23E050003)Ningbo Youth Science and Technology Innovation Leading Talent Project(Grant No.2023QL021).
文摘Additive manufacturing(AM)has revolutionized the production of metal bone implants,enabling unprecedented levels of customization and functionality.Recent advancements in surface-modification technologies have been crucial in enhancing the performance and biocompatibility of implants.Through leveraging the versatility of AM techniques,particularly powder bed fusion,a range of metallic biomaterials,including stainless steel,titanium,and biodegradable alloys,can be utilized to fabricate implants tailored for craniofacial,trunk,and limb bone reconstructions.However,the potential of AM is contingent on addressing intrinsic defects that may hinder implant performance.Techniques such as sandblasting,chemical treatment,electropolishing,heat treatment,and laser technology effectively remove residual powder and improve the surface roughness of these implants.The development of functional coatings,applied via both dry and wet methods,represents a significant advancement in surface modification research.These coatings not only improve mechanical and biological interactions at the implant-bone interface but also facilitate controlled drug release and enhance antimicrobial properties.Addition-ally,micro-and nanoscale surface modifications using chemical and laser techniques can precisely sculpt implant surfaces to promote the desired cellular responses.This detailed exploration of surface engineering offers a wealth of opportunities for creating next-generation implants that are not only biocompatible but also bioactive,laying the foundation for more effective solutions in bone reconstruction.
基金supported by the National Science Foundation of China(Nos.81373970,81773902,81973484,and 32171402)the National College Students Innovation and Entrepreneurship Training Program(No.201810315019)+4 种基金the Postgraduate Research and Practice Innovation Program of Jiangsu Province(Nos.SJCX21_0712 and KYCX23_2052)the Scientific Research Project of Jiangsu Provincial Association of Traditional Chinese Medicine(No.XYLD2024013)the Youth Scientific Research Project of Jiangyin Municipal Health Commission(No.Q202402)the Natural Science Foundation Project of Nanjing University of Chinese Medicine(No.XZR2024173)the Jiangyin Science and Technology Innovation Special Fund Project(No.JY0603A011014230032PB),China.
文摘Bone repair remains an important target in tissue engineering,making the development of bioactive scaffolds for effective bone defect repair a critical objective.In this study,β-tricalcium phosphate(β-TCP)scaffolds incorporated with processed pyritum decoction(PPD)were fabricated using three-dimensional(3D)printing-assisted freeze-casting.The produced composite scaffolds were evaluated for their mechanical strength,physicochemical properties,biocompatibility,in vitro proangiogenic activity,and in vivo efficacy in repairing rabbit femoral defects.They not only demonstrated excellent physicochemical properties,enhanced mechanical strength,and good biosafety but also significantly promoted the proliferation,migration,and aggregation of pro-angiogenic human umbilical vein endothelial cells(HUVECs).In vivo studies revealed that all scaffold groups facilitated osteogenesis at the bone defect site,with theβ-TCP scaffolds loaded with PPD markedly enhancing the expression of neurogenic locus Notch homolog protein 1(Notch1),vascular endothelial growth factor(VEGF),bone morphogenetic protein-2(BMP-2),and osteopontin(OPN).Overall,the scaffolds developed in this study exhibited strong angiogenic and osteogenic capabilities both in vitro and in vivo.The incorporation of PPD notably promoted the angiogenic-osteogenic coupling,thereby accelerating bone repair,which suggests that PPD is a promising material for bone repair and that the PPD/β-TCP scaffolds hold great potential as a bone graft alternative.
基金funded by the TaipeiMedical University-National Taiwan University of Science and Technology joint research program under Grant No.TMU-NTUST-109-09.
文摘Reconstruction of a traumatic distal femur defect remains a therapeutic challenge.Bone defect implants have been proposed to substitute the bone defect,and their biomechanical performances can be analyzed via a numerical approach.However,the material assumptions for past computational human femur simulations were mainly homogeneous.Thus,this study aimed to design and analyze scaffolds for reconstructing the distal femur defect using a patient-specific finite element modeling technique.A three-dimensional finite element model of the human femur with accurate geometry and material distribution was developed using the finite element method and material mapping technique.An intact femur and a distal femur defect model treated with nine microstructure scaffolds and two solid scaffolds were investigated and compared under a single-leg stance loading.The results showed that the metal solid scaffold design could provide the most stable fixation for reconstructing the distal femur defect.However,the fixation stability was affected by various microstructure designs and pillar diameters.A microstructure scaffold can be designed to satisfy all the biomechanical indexes,opening up future possibilities for more stable reconstructions.A three-dimensional finite element model of the femur with real bone geometry and bone material distribution can be developed,and this patient-specific femur model can be used for studying other femoral fractures or injuries,paving the way for more comprehensive research in the field.Besides,this patient-specific finite element modeling technique can also be applied to developing other human or animal bone models,expanding the scope of biomechanical research.
基金support from the National Institute of Health(K99AR081897,R00AR081897)M.N.W.acknowledges funding support from the National Institute of Health(P01DK011794,R01DK116716)+1 种基金the Smith Family Foundation Odyssey Award,and the Chen Institute Massachusetts General Hospital Research Scholar(2024-2029)awardμCT and bone histomorphometry were performed by the Center for Skeletal Research at Massachusetts General Hospital,a NIH-funded program(P30AR066261 and AR075042)led by Mary Bouxsein and Marie Demay).
文摘Osteogenesis imperfecta(OI)is a group of diseases caused by defects in type I collagen processing which result in skeletal fragility.While these disorders have been regarded as defects in osteoblast function,the role of matrix-embedded osteocytes in OI pathogenesis remains largely unknown.Homozygous human SP7(c.946 C>T,R316C)mutation results in a recessive form of OI characterized by fragility fractures,low bone mineral density and osteocyte dendrite defects.To better understand how the OI-causing R316C mutation affects the function of SP7,we generated Sp7^(R342C)knock-in mice.Consistent with patient phenotypes,Sp7^(R342C/R342C)mice demonstrate increased cortical porosity and reduced cortical bone mineral density.Sp7^(R342C/R342C)mice show osteocyte dendrite defects,increased osteocyte apoptosis,and intracortical bone remodeling with ectopic intracortical osteoclasts and elevated osteocyte Tnfsf11 expression.
文摘This study aimed to utilize micro-computed tomography （micro-CT） analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite （CFB-HAP） or collagen （Bio-Gide） membranes. Fifty-four （54） rats were studied. A circular bony defect （8 mm diameter） was formed in the centre of the calvaria using a trephine bur. The CFB-HAP membrane was prepared by thermally induced phase separation. In the experimental group （n= 18）, the CFB-HAP membrane was used to cover the bony defect, and in the control group （n= 18）, a resorbable collagen membrane （Bio-Gide） was used. In the negative control group （n= 18）, no membrane was used. In each group, six animals were euthanized at 2, 4 and 8 weeks after surgery. The specimens were then analysed using micro-CT. There were significant differences in bone volume （BV） and bone mineral density （BMD） （P〈O.05） between the negative control group and the membrane groups. However, there were no significant differences between the CFB-HAP group and the collagen group. We concluded that the CFB-HAP membrane has significant potential as a guided bone regeneration （GBR） membrane.
基金supported by the Science and Technology Development Plan Project Fund of Jilin Province in China,No.20110492
文摘We hypothesized that a chemically extracted acellular allogeneic nerve graft used in combination with bone marrow mesenchymal stem cell transplantation would be an effective treatment for long-segment sciatic nerve defects.To test this,we established rabbit models of 30 mm sciatic nerve defects,and treated them using either an autograft or a chemically decellularized allogeneic nerve graft with or without simultaneous transplantation of bone marrow mesenchymal stem cells.We compared the tensile properties,electrophysiological function and morphology of the damaged nerve in each group.Sciatic nerves repaired by the allogeneic nerve graft combined with stem cell transplantation showed better recovery than those repaired by the acellular allogeneic nerve graft alone,and produced similar results to those observed with the autograft.These findings confirm that a chemically extracted acellular allogeneic nerve graft combined with transplantation of bone marrow mesenchymal stem cells is an effective method of repairing long-segment sciatic nerve defects.
文摘BACKGROUND Ilizarov non-free bone plasty is a method of distraction osteogenesis using the Ilizarov apparatus for external fixation which originated in Russia and was disseminated across the world. It has been used in long bone defect and nonunion management along with free vascularized grafting and induced membrane technique. However, the shortcomings and problems of these methods still remain the issues which restrict their overall use.AIM To study the recent available literature on the role of Ilizarov non-free bone plasty in long bone defect and nonunion management, its problems and the solutions to these problems in order to achieve better treatment outcomes.METHODS Three databases(Pub Med, Scopus, and Web of Science) were searched for literature sources on distraction osteogenesis, free vascularized grafting and induced membrane technique used in long bone defect and nonunion treatment within a five-year period(2015-2019). Full-text clinical articles in the English language were selected for analysis only if they contained treatment results,complications and described large patient samples(not less than ten cases for congenital, post-tumor resection cases or rare conditions, and more than 20 cases for the rest). Case reports were excluded.RESULTS Fifty full-text articles and reviews on distraction osteogenesis were chosen.Thirty-five clinical studies containing large series of patients treated with this method and problems with its outcome were analyzed. It was found that distraction osteogenesis techniques provide treatment for segmental bone defects and nonunion of the lower extremity in many clinical situations, especially in complex problems. The Ilizarov techniques treat the triad of problems simultaneously(bone loss, soft-tissue loss and infection). Management of tibial defects mostly utilizes the Ilizarov circular fixator. Monolateral fixators are preferable in the femur. The use of a ring fixator is recommended in patients with an infected tibial bone gap of more than 6 cm. High rates of successful treatment were reported by the authors that ranged from 77% to 100% and depended on the pathology and the type of Ilizarov technique used. Hybrid fixation and autogenous grafting are the most applicable solutions to avoid after-frame regenerate fracture or deformity and docking site nonunion.CONCLUSION The role of Ilizarov non-free bone plasty has not lost its significance in the treatment of segmental bone defects despite the shortcomings and treatment problems encountered.
基金King Saud University,through Vice Deanship of Research Chairs
文摘The aim of the present real time in vivo micro-computed tomography （pCT） and histologic experiment was to assess the efficacy of guided bone regeneration （GBR） around standardized calvarial critical size defects （CSD） using bone marrow-derived mesenchymal stem cells （BMSCs）, and collagen membrane （CM） with and without tricalcium phosphate （TCP） graft material. In the calvaria of nine female Sprague-Dawley rats, full-thickness CSD （diameter 4.6 mm） were created under general anesthesia. Treatment-wise, rats were divided into three groups. In group 1, CSD was covered with a resorbable CM; in group 2, BMSCs were filled in CSD and covered with CM; and in group 3, TCP soaked in BMSCs was placed in CSD and covered with CM. All defects were closed using resorbable sutures. Bone volume and bone mineral density of newly formed bone （NFB） and remaining TCP particles and rate of new bone formation was determined at baseline, 2, 4, 6, and 10 weeks using in vivo pCT. At the lOth week, the rats were killed and calvarial segments were assessed histologically. The results showed that the hardness of NFB was similar to that of the native bone in groups I and 2 as compared to the NFB in group 3. Likewise, values for the modulus of elasticity were also significantly higher in group 3 compared to groups 1 and 2. This suggests that TCP when used in combination with BMSCs and without CM was unable to form bone of significant strength that could possibly provide mechanical ＂lock＂ between the natural bone and NFB. The use of BMSCs as adjuncts to conventional GBR initiated new bone formation as early as 2 weeks of treatment compared to when GBR is attempted without adiunct BMSC therapy.
