Reconstruction Of Bone Defects Research Articles

Alendronate-decorated strontium-containing bioactive glass nanoparticles with dual osteogenic and anti-osteoclastic effects for osteoporosis

Bioactive glass (BG) has emerged as a promising material for bone regeneration. In this study, strontium-doped bioactive glass nanoparticles loaded with alendronate (A-SrBG) were fabricated and characterized to evaluate their potential for bone regeneration in osteoporosis. A-SrBG nanoparticles have excellent bioactivity, inducing apatite mineralization and achieving sustained release of bioactive ions in vitro. Moreover, A-SrBG nanoparticles could promote the differentiation of osteoblasts while inhibiting the differentiation of osteoclasts by preventing RANKL-induced activation of the NF-κB and mevalonate pathways. A-SrBG nanoparticles could be phagocytosed into the cells and present in the cytoplasm, which could enhance the efficiency of ALN. When implanted in vivo, A-SrBG discs promoted the regeneration of new bone. The results demonstrated that the ability of A-SrBG to dually regulate both osteogenesis and osteoclastogenesis makes it a promising candidate for the reconstruction of bone defects in osteoporosis.

Decellularization of Massive Bone Allografts By Perfusion: A New Protocol for Tissue Engineering.

In terms of large bone defect reconstructions, massive bone allografts may sometimes be the only solution. However, they are still burdened with a high postoperative complication rate. Our hypothesis is that the immunogenicity of residual cells in the graft is involved in this issue. Decellularization by perfusion might therefore be the answer to process and create more biologically effective massive bone allografts. Seventy-two porcine bones were used to characterize the efficiency of our sodium hydroxide-based decellularization protocol. A sequence of solvent perfusion through each nutrient artery was set up to ensure the complete decellularization of whole long bones. Qualitative (histology and immunohistochemistry [IHC]) and quantitative (fluoroscopic absorbance and enzyme-linked immunosorbent assay) evaluations were performed to assess the decellularization and the preservation of the extracellular matrix in the bone grafts. Cytotoxicity and compatibility were also tested. Comparatively to nontreated bones, our experiments showed a very high decellularization quality, demonstrating that perfusion is mandatory to achieve an entire decellularization. Moreover, results showed a good preservation of the bone composition and microarchitecture, Haversian systems and vascular network included. This protocol reduces the human leukocyte antigen antigenic load of the graft by >50%. The majority of measured growth factors is still present in the same amount in the decellularized bones compared to the nontreated bones. Histology and IHC show that the bones were cell compatible, noncytotoxic, and capable of inducing osteoblastic differentiation of mesenchymal stem cells. Our decellularization/perfusion protocol allowed to create decellularized long bone graft models, thanks to their inner vascular network, ready for in vivo implantation or to be further used as seeding matrices.

High temperature oxidation treated 3D printed anatomical WE43 alloy scaffolds for repairing periarticular bone defects: In vitro and in vivo studies

Reconstruction of subarticular bone defects is an intractable challenge in orthopedics. The simultaneous repair of cancellous defects, fractures, and cartilage damage is an ideal surgical outcome. 3D printed porous anatomical WE43 (magnesium with 4 wt% yttrium and 3 wt% rare earths) scaffolds have many advantages for repairing such bone defects, including good biocompatibility, appropriate mechanical strength, customizable shape and structure, and biodegradability. In a previous investigation, we successfully enhanced the corrosion resistance of WE43 samples via high temperature oxidation (HTO). In the present study, we explored the feasibility and effectiveness of HTO-treated 3D printed porous anatomical WE43 scaffolds for repairing the cancellous bone defects accompanied by split fractures via in vitro and in vivo experiments. After HTO treatment, a dense oxidation layer mainly composed of Y2O3 and Nd2O3 formed on the surface of scaffolds. In addition, the majority of the grains were equiaxed, with an average grain size of 7.4 μm. Cell and rabbit experiments confirmed the non-cytotoxicity and biocompatibility of the HTO-treated WE43 scaffolds. After the implantation of scaffolds inside bone defects, their porous structures could be maintained for more than 12 weeks without penetration and for more than 6 weeks with penetration. During the postoperative follow-up period for up to 48 weeks, radiographic examinations and histological analysis revealed that abundant bone gradually regenerated along with scaffold degradation, and stable osseointegration formed between new bone and scaffold residues. MRI images further demonstrated no evidence of any obvious damage to the cartilage, ligaments, or menisci, confirming the absence of traumatic osteoarthritis. Moreover, finite element analysis and biomechanical tests further verified that the scaffolds was conducive to a uniform mechanical distribution. In conclusion, applying the HTO-treated 3D printed porous anatomical WE43 scaffolds exhibited favorable repairing effects for subarticular cancellous bone defects, possessing great potential for clinical application.

Applicative Assessment of a Selective Laser Melting 3D-Printed Ti-6Al-4 V Plate with a Honeycomb Structure in the Reconstruction of a Mandibular Defect of a Beagle Dog.

The most challenging problem in oral and maxillofacial surgery is the reconstruction of defects for the oral and maxillofacial complex. Transfer of different autografts is known as the "gold standard" for the reconstruction of bone defects in the oral and maxillofacial region. Graft harvesting, however, can lead to many complications, such as donor-site morbidity, surgical time-consuming, etc. Three-dimensional (3D) printing technology is an innovative technique that allows the fabrication of personalized plates and scaffolds to fit the precise anatomy of an individual's defect. In this study, a selective laser melting 3D-printed Ti-6Al-4 V plate with a honeycomb was designed, and its physical and biological features were characterized. The personalized 3D-printed scaffold and commercialized titanium reconstruction plate were applied to reconstruct a 4 cm mandibular defect in a beagle dog. Effects of the treatment were analyzed radiologically and histologically. Our results showed that the application of a 3D-printed plate with a honeycomb achieved good biocompatibility and osseointegration and has potential clinical application.

Reconstruction of the proximal radius with 3D-printed personalized prosthesis after tumor resection: case series

Giant cell tumor of bone (GCTB) (Campanacci III) or malignant tumors extend to the epiphyseal region, and intra-articular resection of the proximal radius is often needed. In the present study, we present the patients who underwent reconstruction of the proximal radius with 3D-printed personalized prosthesis after tumor resection, aiming to describe the prosthesis design and surgical technique and evaluate the clinical outcomes of this method. Between November 2018 and January 2021, nine patients received radial hemiarthroplasty with 3D-printed personalized prostheses after tumor resection. The pathological diagnosis was GCTB (Campanacci III) in seven patients, osteosarcoma (IIB) in one patient, and synovial sarcoma (IIB) in one patient. The range of motion (ROM) and strength in terms of elbow flexion/extension and forearm supination/pronation were evaluated. Pain was assessed by the visual analog scale (VAS) preoperatively and at each follow-up visit. To evaluate the functional outcome, the Mayo Elbow Performance Score (MEPS) system and the Musculoskeletal Tumor Society (MSTS) scoring system were administered at each follow-up visit. Complications and oncological outcomes were recorded. The patients were followed from 24 to 51 months, with a median follow-up of 35 months. No patients were lost to follow-up. During the follow-up, local recurrence and metastasis were not observed. The VAS score improved from a median of 5 points (range 4 to 7) preoperatively to 1 point (range 0 to 2) at the last follow-up visit. The mean MEPS score was 88.5% (83 to 93), and the mean MSTS score was 25.3 (24 to 27) at the last follow-up visit. No complications such as infection and aseptic loosening were detected. The implantation of a 3D-printed personalized prosthesis after proximal radial resection showed excellent oncologic outcomes and postoperative function at short-term follow-up and is a viable alternative method for reconstruction of the proximal radius bone defect after tumor resection.

Comparison of the Results of Patients Treated With Limb-Sparing Treatment Options in Malignant Bone Tumors: Sharing the Experience of Twelve Bicentric Patients.

Extremity-sparing surgery should be the main objective if a functional extremity is to be obtained in cases of malignant bone tumors. After extensive resection, numerous techniques have been described to reconstruct bone defects. This study aimed to compare the outcomes of patients who underwent external radiation therapy and liquid nitrogen biological reconstruction at two different facilities. The study included 12 patients who received biological reconstruction therapy for bone sarcoma and had at least two years of follow-up. Demographic data, pathological diagnosis, presence of systemic metastasis, and recurrence during follow-up were among the information logged. Patients who used liquid nitrogen were placed in group 1, and those who underwent external irradiation were placed in group 2. After being contacted for their final follow-up appointments, the outcomes were compared by recording the Musculoskeletal Tumor Society Score (MSTSS). For participants with a mean age of 10.75±3.6 (5-17), the follow-up period was 30.2±16.3 months in total. In contrast to the patients in group 1, who experienced union on average after 7.5±1.2 months, those in group 2 experienced union after 7.6±1.1 months. Patients in group 1 had an MSTSS of 75.5±11.8%, while those in group 2 had a score of 77±4.4.There was no discernible difference between the two groups' union times (p>0.05). There was no statistically significant difference between the two groups' MSTSS (p>0.05). After tumor resection, extracorporeal radiation therapyand the application of liquid nitrogen are still useful treatment options and neither of them is superior to the other.

Chlorite-incorporated clay nanosheets as acid and H2O2-activated gas-bombs for combating peri-implant infection

Persistent and recurrent bacterial infections pose significant challenges during the repair and reconstruction of bone defects, necessitating the development of effective solutions to this problem. Herein, a chlorine dioxide delivery platform (LDH@Cl) comprising chlorite-incorporated clay nanosheets (MgFe layered double hydroxides, MgFe LDH) is designed and constructed. The LDH@Cl gas bomb exploits self-promoted chemical reactions in an acidic and H2O2-rich microenvironment, generating substantial amounts of ClO2 and ·OH, which exhibit potent antibacterial activity. LDH@Cl exhibits half-maximal inhibitory concentrations of 0.69 mM and 0.78 mM against Escherichia coli and Staphylococcus aureus, respectively. Furthermore, LDH@Cl exhibits good biocompatibility at a low concentration of 0.08 mM; and significant osteogenic induction effects at a high concentration of 0.8 mM, which is attributed to the release of Mg ions and Fe ions in a normal microenvironment. Furthermore, LDH@Cl promotes the expression of the osteogenic channel signaling protein BMP2, which stimulates the expression of the downstream signaling factors SMAD1, SMAD2, and SMAD3, thereby regulating the synthesis of osteogenic-related proteins. Importantly, in vivo studies demonstrate the positive therapeutic effects of LDH@Cl in bacterial eradication and accelerated osteogenesis. Thus, this novel nano “gas bomb” is promising for the clinical treatment of bacterial infection related bone defect regeneration.

Optimize the pore size-pore distribution-pore geometry-porosity of 3D-printed porous tantalum to obtain optimal critical bone defect repair capability

The treatment and reconstruction of large or critical size bone defects is a challenging clinical problem. Additive manufacturing breaks the technical difficulties of preparing complex conformation and anatomically matched personalized porous tantalum implants, but the ideal pore structure for 3D-printed porous tantalum in critical bone defect repair applications remains unclear. Guiding appropriate bone tissue regeneration by regulating proper pore size-pore distribution-pore geometry-porosity is a challenge for its fabrication and application. We fabricated porous tantalum (PTa) scaffolds with six different combinations of pore structures using powder bed laser melting (L-PBF) technology. In vitro biological experiments were conducted to systematically investigate the effects of pore structure characteristics on osteoblast behaviors, showing that the bionic trabecular structure with both large and small poress facilitated cell permeation, proliferation and differentiation compared to the cubic structure with uniform pore sizes. The osteogenesis of PTa with different porosity of trabecular structures was further investigated by a rabbit condyle critical bone defect model. Synthetically, T70% up-regulated the expression of osteogenesis-related genes (ALP, COLI, OCN, RUNX-2) and showed the highest bone ingrowth area and bone contact rate in vivo after 16 weeks, with the best potential for critical bone defect repair. Our results suggested that the bionic trabecular structure with a pore size distribution of 200–1200 μm, an average pore size of 700 μm, and a porosity of 70 % is the best choice for repairing critical bone defects, which is expected to guide the clinical application of clinical 3D-printed PTa scaffolds.

3D-Printed Osteoinductive Polymeric Scaffolds with Optimized Architecture to Repair a Sheep Metatarsal Critical-Size Bone Defect.

The reconstruction of critical-size bone defects in long bones remains a challenge for clinicians. A new osteoinductive medical device is developed here for long bone repair by combining a 3D-printed architectured cylindrical scaffold made of clinical-grade polylactic acid (PLA) with a polyelectrolyte film coating delivering the osteogenic bone morphogenetic protein 2 (BMP-2). This film-coated scaffold is used to repair a sheep metatarsal 25-mm long critical-size bone defect. In vitro and in vivo biocompatibility of the film-coated PLA material is proved according to ISO standards. Scaffold geometry is found to influence BMP-2 incorporation. Bone regeneration is followed using X-ray scans, µCT scans, and histology. It is shown that scaffold internal geometry, notably pore shape, influenced bone regeneration, which is homogenous longitudinally. Scaffolds with cubic pores of ≈870µm and a low BMP-2 dose of ≈120µgcm-3 induce the best bone regeneration without any adverse effects. The visual score given by clinicians during animal follow-up is found to be an easy way to predict bone regeneration. This work opens perspectives for a clinical application in personalized bone regeneration.

Stability of Three-Dimensional Printed Custom-Made Metaphyseal Cone for Tibial Bone Defects Reconstruction: A Finite Element Analysis and Biomechanical Study.

The reconstruction of bone defects in tibial revision knee arthroplasty is challenging. In this study, we evaluated the primary stability of a novel three-dimensional (3D)-printed custom-made metaphyseal cone for Anderson Orthopedic Research Institute (AORI) IIb or III bone defect reconstruction in tibial revision knee arthroplasty using the combination of finite-element analysis and biomechanical experiments. In the finite-element analysis, AORI II b and III medial tibial bone defects were designed at varying depths. A novel 3D-printed custom-made metaphyseal cone was designed and used to reconstruct the bone defect with or without a stem in simulated revision total knee arthroplasty (RTKA). A no-stem group and a stem group were established (based on whether a stem was used or not). Von Mises stress and micromotion were calculated with varying depths of bone defects, ranging from 5 mm to 35 mm, and then micromotions at the bone-implant interface were calculated and compared with the critical value of 150 μm. In the biomechanical experiment, the no-stem group was used, and the same bone defects were made in four synthetic tibias using patient-specific instruments. Micromotions at the bone-implant interface were investigated using a non-contact optical digital image correlation system and compared with the critical value of 150 μm. When the bone defect was <30 mm, micromotions at the bone-implant interface in the finite-element analysis were all below 150 μm both in the stem groups and no-stem groups, whereas those in the biomechanical experiment were also below 150 μm in the no-stem group. The 3D-printed custom-made metaphyseal cone in RTKA has excellent primary stability and does not require stems in reconstructing tibial AORI type IIb or III bone defects with a depth of <30 mm.

Reconstruction of Acetabular and Femoral Bone Defects With Impaction Bone Grafting in Revision Hip Arthroplasty: A Case Report

Background. For many years, the main reasons for revision surgeries after hip arthroplasty remain aseptic loosening and osteolysis, which lead to formation of bone defects of various size and localization. Given the relatively young age of patients undergoing revision, the methods of biological restoration of the bone tissue, such as impaction bone grafting (IBG), are of particular interest.&#x0D; Aim of the report to demonstrate the delayed outcome of impaction bone grafting using compacted morselized bone allograft.&#x0D; Case presentation. Complicated clinical case of a 62-year-old patient with Paprosky type IIA bone deficiency in the acetabulum and Paprosky type II bone deficiency in the proximal femur with aseptic loosening of the acetabular and femoral components of the hip prosthesis is presented. During revision arthroplasty with cemented components, IBG of the acetabulum and femur was performed with a reconstructive mesh augmentation of the acetabulum using Stryker X-Change technology. Bone allograft prepared with the use of heat disinfection method served as an osteoplastic material. Follow-up period was 4 years. Control X-rays demonstrate restoration of the center of rotation of the hip, presence of bone masses in the areas of pelvic and femoral bone defects, absence of osteoplastic material resorption and migration of implants during the follow-up period. Clinical assessment shows an improvement of the Harris Hip Score from 34 to 85 points.&#x0D; Conclusion. Obtained results showed the efficacy of impaction bone grafting with the bone allograft prepared with the use of heat disinfection method in the mid-term period.

MiR-34a-Functionalized Hydroxyapatite by Lyophilization Promoted Bone Regeneration in Irradiated Bone Defects

The rehabilitation of bone defects after radiotherapy requires the development of osteoinductive bone substitutes. MicroRNA could be used as an osteogenic factor to fabricate functional materials for bone regeneration. In this study, we used miR-34a to enhance bone regeneration after irradiation. We lyophilized lipofectamine-agomiR-34a lipoplexes on hydroxyapatite (HA) to develop miR-34a-functionalized hydroxyapatite (HA-agomiR-34a). The morphology was observed by scanning electron microscope and atomic force microscope. Fluorescence microscopy confirmed the retention of agomiR-34a on the surface of HA. HA-agomiR-34a showed high transfection efficiency and good biocompatibility. HA-agomiR-34a enhanced the osteoblastic differentiation of radiation-impaired bone marrow stromal cells (BMSCs). Implantation of HA-agomiR-34a promoted bone regeneration in irradiated bone defects. HA-agomiR-34a may be a novel and safe bone substitute to promote the reconstruction of bone defects after radiotherapy.

Reconstruction of Intercalary Bone Defects After Tumour Resection with the Use of a Free Vascularised Fibular Graft: the Concealed Advantages of the External Fixator.

The free vascularised fibular graft represents the mainstay of intercalary bone defect reconstruction after tumour resection. Different reconstruction techniques are described, favouring internal fixation and possibly overlooking potential advantages of external fixation. This series is a description of the technique performed at our institution using an external fixator for the reconstruction of segmental bone defects which enables to maintain limb length and rotational alignment after large segmental bone resection. Data collected were demographic, surgical and histological data, perioperative complications and postoperative data. Eighteen different complications were encountered in seven patients. Mean reoperation rate was 1.3 per patient but no patient required further interventions in order to correct limb length or rotational alignment. Pin-track infection rate was 6%. The limb salvage rate was 100%. Solid final bone healing was obtained in all patients. External fixation for the reconstruction of intercalary bone defects after tumour resection is a safe technique which might offer the advantage of limb length and alignment preservation.

Black phosphorus-incorporated novel Ti-12Mo-10Zr implant for multimodal treatment of osteosarcoma.

The repair and reconstruction of large bone defects after bone tumor resection is still a great clinical challenge. At present, orthopedic implant reconstruction is the mainstream treatment for repairing bone defects. However, according to clinical feedback, local tumor recurrence and nonunion of bone graft are common reasons leading to the failure of bone defect repair and reconstruction after bone tumor resection, which seriously threaten the physical and mental health of patients. On this basis, here the self-developed low modulus Ti-12Mo-10Zr alloy (TMZ) was chosen as substrate material. To improve its biological activity and osteointegration, calcium, oxygen, and phosphorus co-doped microporous coating was prepared on TMZ alloy by microarc oxidation (MAO). Then, black phosphorus (BP) nanosheets were incorporated onto MAO treated TMZ alloy to obtain multifunctional composites. The obtained BP-MAO-TMZ implant exhibited excellent photothermal effects and effective ablation of osteosarcoma cancer cells under the irradiation of 808nm near infrared laser, while no photothermal or therapeutic effects were observed for TMZ alloy. Meanwhile, the structure/component bionic coating obtained after MAO treatment as well as the P-driven in situ biomineralization performance after incorporation of BP nanosheets endowed BP-MAO-TMZ implant with synergistic promoting effect on MC3T3-E1 osteoblasts' activity, proliferation and differentiation ability. This study is expected to provide effective clinical solutions for problems of difficult bone regeneration and tumor recurrence after tumor resection in patients with bone tumors and to solve a series of medical problems such as poor prognosis and poor postoperative quality of patients life with malignant bone tumors.

Does the use of polymethyl-methacrylate cement after intralesional curettage of giant cell tumors of appendicular bone guarantee reduced local recurrence rates? A retrospective analysis.

Polymethyl-methacrylate cement (PMMA) is often used as bone defect reconstruction material after surgical removal of giant cell tumors. The purpose of this study was to investigate if the application of PMMA improves the local recurrence rates for giant cell tumors (GCT) of appendicular bone treated with intralesional curettage. A retrospective analysis of all appendicular GTCs treated at two major Danish sarcoma centres between the 1st of January 1998 and December 31st 2013; minimum follow-up of 3.0years (median: 8.9; 1.3-18.7years). Kaplan-Meier survival model, log-rank and multivariate Cox regression were used to calculate and compare local recurrence rates. p-values <0.05 were considered statistically significant. 102 patients (M59/F43), median age 31Y (11-84) were included in this study. The overall 3-years local recurrence-rate was 19.9% (95%CI: 11.9-27.9%); 91% had occurred within 3years. In patients treated with intralesional curettage (n = 64), the 3-years recurrence-rate was 30.6% (95%CI: 18.8-42.4%), compared to 2.6% (95%CI: 0.0-7.8%) in patients treated with wide resection or amputation (n = 38), p < .001. The 3-years recurrence-rate for patients treated with intralesional curettage and reconstruction using PMMA was 29.0% (95%CI: 12.6-45.4%) and without PMMA: 31.8% (95%CI: 15.2-48.4%), p = .83. We found that the use of PMMA for bone defect reconstruction after intralesional curettage of GTCs in the appendicular skeleton did not ensure a reduced risk of local recurrence.

Discovery of multipotent progenitor cells from human induced membrane: Equivalent to periosteum-derived stem cells in bone regeneration

BackgroundThe periosteum stem cells (PSCs) plays a critical role in bone regeneration and defect reconstruction. Insertion of polymethyl methacrylate (PMMA) bone cement can form an induced membrane(IM) and showed promising strategy for bone defect reconstruction, the underlying mechanism remains unclear. Our study sought to determine whether IM-derived cells(IMDCs) versus PSCs have similar characteristics in bone regeneration. MethodsIM and periosteum were harvested from ten bone defect patients treated with PMMA, the IMDCs and PSCs were isolated respectively. Morphological, functional and molecular evaluation was performed and matched for comparison. ResultsBoth progenitor-like IMDCs and PSCs were successfully isolated. In vitro, we found IMDCs were similar to PSCs in morphology, colony forming capacity and expression of surface marker(CD90+, CD73+, CD105+, CD34-/CD45-). Meanwhile, these IMSCs displayed multipotency with chondrogenic, adipogenic and osteogenic differentiation, but differed in some IMSCs(3/10) population showing relatively poor osteogenic differentiation. The molecular profiles suggests that cell cycle and DNA replication signaling pathways were associated with these varying osteogenic potential. In vivo, we established a cell-based tissue-engineered bone by seeding IMDSs/PSCs to demineralized bone matrix (DBM) scaffold and demonstrated both IMDSs and PSCs enhanced bone regeneration in SCID mice bone defect model compared with DBM alone. ConclusionOur data demonstrated IM containing multipotent progenitor cells similar to that periosteum promoting bone regeneration, and indicated the existence of multiple subsets in osteogenic differentiation. Overall, the study provided a cellular and molecular insights in understanding the successful or failed outcome of bone defect healing.The translational potential of this article: This study confirmed IMDCs and PSCs share similar regeneration capacity and inform a translation potential of that cellular therapy applying IMDCs in bone defect repair.

Microsurgical autologous ffbula transfer as an optimal method for closure of extensive bone defects in children with neuroffbromatosis

Introduction Pseudarthrosis and bone defects are the most common consequence of neurofibromatosis type I in children, a rare hereditary disease. Destruction of bone tissue leads to severe deformities and impaired function of the limbs. Disability in such patients may reach 70 %. Surgical treatment of children with this pathology is long, laborious and multi-stage. Traditional orthopaedic methods for managing bone defects are often ineffective. The development of microsurgical methods enables to perform bone transfer of blood-supplied bone autografts.Purpose To prove the effectiveness of using microsurgical autologous transfer of the vascularized fibula for plastic surgery of bone defects in children with neurofibromatosis type I.Materials and methods A retrospective monocenter study included 27 pediatric patients who underwent reconstruction of bone defects with a vascularized fibular autograft from 2011 to 2021. The etiology of the bone defect in all patients was neurofibromatosis type I. A fibula graft was used to reconstruct 8 tibiae and 19 forearms. Bone defects averaged 12 cm. Median follow-up was 60 months.Results The fibula graft survival rate was 100 %. In 5 cases, nonunion of the proximal part of the fibula and the recipient zone was obtained which required iliac crest grafting. The overall rate of good and excellent results was 74 %. The average time to consolidation was 3 months. Discussion According to the literature, the use of autografting of vascularized bone fragments is a ather limited procedure in children with neurofibromatosis type I as it is associated with an increased risk of complications. Due to the restoration of blood flow in the transferred vascularized autograft, it retains its viability and the possibility of bone tissue remodeling.Conclusion Microsurgical autologous transfer of a vascularised fragment of the fibula is an effective and at times indispensable method of bone plasty in long bone defects in children with type 1 neurofibromatosis. Bone defects larger than 5 cm are an indication for free autologous transfer of a vascularized fragment of the fibula. This method, used in combination with traditional orthopedic methods for the treatment of children, allows obtaining good anatomical and functional results.

The application of 3D-printed auto-stable artificial vertebral body in en bloc resection and reconstruction of thoracolumbar metastases

BackgroundNerve compression symptoms and spinal instability, resulting from spinal metastases, significantly impact the quality of life for patients. A 3D-printed vertebral body is considered an effective approach to reconstruct bone defects following en bloc resection of spinal tumors. The advantage of this method lies in its customized shape and innermost porous structure, which promotes bone ingrowth and leads to reduced postoperative complications.ObjectiveThe purpose of this study is to assess the effectiveness of 3D-printed auto-stable artificial vertebrae in the en bloc resection and reconstruction of thoracolumbar metastases.MethodsThis study included patients who underwent en bloc resection of thoracolumbar metastases based on the Weinstein-Boriani-Biagini surgical staging system, between January 2019 and April 2021. The patients were divided into two groups: the observation group, which was reconstructed using 3D-printed auto-stable vertebral bodies, and the control group, treated with titanium cages and allograft bone. Evaluation criteria for the patients included assessment of implant subsidence, instrumentation-related complications, VAS score, and Frankel grading of spinal cord injury.ResultsThe median follow-up period was 21.8 months (range 12–38 months). Among the patients, 10 received a customized 3D-printed artificial vertebral body, while the remaining 10 received a titanium cage. The observation group showed significantly lower operation time, intraoperative blood loss, and postoperative drainage compared to the control group (P < 0.05). At the final follow-up, the average implant subsidence was 1.8 ± 2.1 mm for the observation group and 5.2 ± 5.1 mm for the control group (P < 0.05). The visual analog scale (VAS) scores were not statistically different between the two groups at preoperative, 24 h, 3 months, and 1 year after the operation (P < 0.05). There were no statistically significant differences in the improvements of spinal cord functions between the two groups.ConclusionThe utilization of a 3D-printed auto-stable artificial vertebra for reconstruction following en bloc resection of thoracolumbar metastases appears to be a viable and dependable choice. The low occurrence of prosthesis subsidence with 3D-printed prostheses can offer immediate and robust stability.

Design and manufacturing of biomimetic scaffolds for bone repair inspired by bone trabeculae

Porous scaffold (PorS) implants, particularly those that mimic the structural features of natural cancellous bone (NCanB), are increasingly essential for the treatment of large-area bone defects. However, the mechanical properties of NCanB-based bionic bone scaffold (BioS) and its performance as a bone repair material have not been fully explored. This study investigates the effect of bionic structure parameters on the mechanical properties and bone reconstruction performance of BioS. Using laser powder bed fusion (L-PBF) technology, different BioS with various structural parameters were created and evaluated using Micro-CT, compression testing, Finite Element (FE) Simulation, and computational fluid dynamics (CFD), and compared to commonly used clinical PorS. Assess the capacity of the BioS scaffold to support and enhance bone reconstruction following implantation through the evaluation of its mechanical properties, permeability, and fluid shear stress (FSS). BioS-85-90 and BioS-80-50 showed suitable mechanical properties, performed well in FE simulation of implantation, demonstrated outstanding abilities for osteoinductive ingrowth and bone tissue differentiation, and proved to be reliable materials for the reconstruction of bone defects. Therefore, BioS shows significant potential for clinical application as a bone reconstruction material, providing a solid foundation for the integration of tissue engineering and bionic design.

Research progress of 3D printed poly (ether ether ketone) in the reconstruction of craniomaxillofacial bone defects.

The clinical challenge of bone defects in the craniomaxillofacial region, which can lead to significant physiological dysfunction and psychological distress, persists due to the complex and unique anatomy of craniomaxillofacial bones. These critical-sized defects require the use of bone grafts or substitutes for effective reconstruction. However, current biomaterials and methods have specific limitations in meeting the clinical demands for structural reinforcement, mechanical support, exceptional biological performance, and aesthetically pleasing reconstruction of the facial structure. These drawbacks have led to a growing need for novel materials and technologies. The growing development of 3D printing can offer significant advantages to address these issues, as demonstrated by the fabrication of patient-specific bioactive constructs with controlled structural design for complex bone defects in medical applications using this technology. Poly (ether ether ketone) (PEEK), among a number of materials used, is gaining recognition as a feasible substitute for a customized structure that closely resembles natural bone. It has proven to be an excellent, conformable, and 3D-printable material with the potential to replace traditional autografts and titanium implants. However, its biological inertness poses certain limitations. Therefore, this review summarizes the distinctive features of craniomaxillofacial bones and current methods for bone reconstruction, and then focuses on the increasingly applied 3D printed PEEK constructs in this field and an update on the advanced modifications for improved mechanical properties, biological performance, and antibacterial capacity. Exploring the potential of 3D printed PEEK is expected to lead to more cost-effective, biocompatible, and personalized treatment of craniomaxillofacial bone defects in clinical applications.