scholarly journals Vascularization of Nanohydroxyapatite/Collagen/Poly(L-lactic acid) Composites by Implanting Intramuscularly In Vivo

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Hai Wang ◽  
Xiao Chang ◽  
Guixing Qiu ◽  
Fuzhai Cui ◽  
Xisheng Weng ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Orthopaedic Surgery ◽  
Bone Substitutes ◽  
Bone Defects ◽  
Large Defect ◽  
Natural Bone ◽  
Composition And Structure ◽  
Large Bone ◽  
Large Bone Defects

It still remains a major challenge to repair large bone defects in the orthopaedic surgery. In previous studies, a nanohydroxyapatite/collagen/poly(L-lactic acid) (nHAC/PLA) composite, similar to natural bone in both composition and structure, has been prepared. It could repair small sized bone defects, but they were restricted to repair a large defect due to the lack of oxygen and nutrition supply for cell survival without vascularization. The aim of the present study was to investigate whether nHAC/PLA composites could be vascularized in vivo. Composites were implanted intramuscularly in the groins of rabbits for 2, 6, or 10 weeks (n=5×3). After removing, the macroscopic results showed that there were lots of rich blood supply tissues embracing the composites, and the volumes of tissue were increasing as time goes on. In microscopic views, blood vessels and vascular sprouts could be observed, and microvessel density (MVD) of the composites trended to increase over time. It suggested that nHAC/PLA composites could be well vascularized by implanting in vivo. In the future, it would be possible to generate vascular pedicle bone substitutes with nHAC/PLA composites for grafting.

Hydroxyapatite scaffold pore architecture effects in large bone defects in vivo

2013 ◽  
Vol 28 (7) ◽  
pp. 1016-1027 ◽  
Author(s):  
Teja Guda ◽  
John A Walker ◽  
Brian Singleton ◽  
Jesus Hernandez ◽  
Daniel S Oh ◽  
...  
Keyword(s):  
Bone Defects ◽  
Pore Architecture ◽  
Hydroxyapatite Scaffold ◽  
Large Bone ◽  
Large Bone Defects

scholarly journals Ordinary and Activated Bone Grafts: Applied Classification and the Main Features

2015 ◽  
Vol 2015 ◽  
pp. 1-19 ◽  
Author(s):  
R. V. Deev ◽  
A. Y. Drobyshev ◽  
I. Y. Bozo ◽  
A. A. Isaev
Keyword(s):  
Growth Factors ◽  
Biological Effects ◽  
Bone Grafts ◽  
Bone Substitutes ◽  
Bone Defects ◽  
Biologically Active ◽  
Active Components ◽  
Or Gene ◽  
Large Bone ◽  
Large Bone Defects

Bone grafts are medical devices that are in high demand in clinical practice for substitution of bone defects and recovery of atrophic bone regions. Based on the analysis of the modern groups of bone grafts, the particularities of their composition, the mechanisms of their biological effects, and their therapeutic indications, applicable classification was proposed that separates the bone substitutes into “ordinary” and “activated.” The main differential criterion is the presence of biologically active components in the material that are standardized by qualitative and quantitative parameters: growth factors, cells, or gene constructions encoding growth factors. The pronounced osteoinductive and (or) osteogenic properties of activated osteoplastic materials allow drawing upon their efficacy in the substitution of large bone defects.

Technique for Use of Trabecular Metal Spacers in Tibiotalocalcaneal Arthrodesis With Large Bony Defects

2016 ◽  
Vol 38 (1) ◽  
pp. 96-106 ◽  
Author(s):  
Christopher Kreulen ◽  
Evan Lian ◽  
Eric Giza
Keyword(s):  
Bone Defects ◽  
Trabecular Metal ◽  
Leg Length ◽  
Large Defect ◽  
Operative Strategy ◽  
Metal Implant ◽  
Tibiotalocalcaneal Arthrodesis ◽  
Structural Bone Graft ◽  
Large Bone ◽  
Large Bone Defects

There are many causes of large bone defects in the tibiotalar joint that need to be definitively treated with a tibiotalocalcaneal (TTC) arthrodesis. Some of the challenges of a large defect are its effect on leg length and the complications associated with trying to fill the defect with structural bone graft. We present an operative strategy involving the use of a trabecular metal implant, a TTC nail that utilized 2 forms of compression, and Reamer/Irrigator/Aspirator (RIA) autograft, to address limitations of previous operative approaches and reliably treat this operative challenge.

The reconstruction of large bone defects by novel functionalized polymers: an in vitro and in vivo experimental study

1993 ◽  
Vol 12 (13) ◽  
pp. 979-981 ◽  
Author(s):  
E. Dalas ◽  
P. Megas ◽  
M. Tyllianakis ◽  
D. Vynois ◽  
E. Lambiris
Keyword(s):  
Experimental Study ◽  
Bone Defects ◽  
Functionalized Polymers ◽  
Large Bone ◽  
Large Bone Defects

scholarly journals Recapitulating bone development for tissue regeneration through engineered mesenchymal condensations and mechanical cues

2017 ◽  
Author(s):  
Anna M. McDermott ◽  
Samuel Herberg ◽  
Devon E. Mason ◽  
Hope B. Pearson ◽  
James H. Dawahare ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Bone Formation ◽  
Mechanical Loading ◽  
Endochondral Ossification ◽  
Bone Development ◽  
Bone Defects ◽  
Limb Bud ◽  
Large Bone ◽  
Large Bone Defects

ABSTRACTLarge bone defects cannot heal without intervention and have high complication rates even with the best treatments available. In contrast, bone fractures naturally healing with high success rates by recapitulating the process of bone development through endochondral ossification.1 Endochondral tissue engineering may represent a promising paradigm, but large bone defects are unable to naturally form a callus. We engineered mesenchymal condensations featuring local morphogen presentation (TGF-β1) to mimic the cellular organization and lineage progression of the early limb bud. As mechanical forces are 2,3 critical for proper endochondral ossification during bone morphogenesis2,3 and fracture healing, we hypothesized that mechanical cues would be important for endochondral regeneration.4,5 Here, using fixation plates that modulate ambulatory load transfer through dynamic tuning of axial compliance, we found that in vivo mechanical loading was necessary to restore bone function to large bone defects through endochondral ossification. Endochondral regeneration produced zonal cartilage and primary spongiosa mimetic of the native growth plate. Live human chondrocytes contributed to endochondral regeneration in vivo, while cell devitalization prior to condensation transplantation abrogated bone formation. Mechanical loading induced regeneration comparable to high-dose BMP-2 delivery, but without heterotopic bone formation and with order-of-magnitude greater mechanosensitivity.6–8In vitro, mechanical loading promoted chondrogenesis, and upregulated pericellular collagen 6 deposition and angiogenic gene expression. Consistently, in vivo mechanical loading regulated cartilage formation and neovascular invasion dependent on load timing. Together, this study represents the first demonstration of the effects of mechanical loading on transplanted cell-mediated bone defect regeneration, and provides a new template for recapitulating developmental programs for tissue engineering.

scholarly journals Heparin-mediated delivery of bone morphogenetic protein-2 improves spatial localization of bone regeneration

2020 ◽  
Vol 6 (1) ◽  
pp. eaay1240 ◽  
Author(s):  
Marian H. Hettiaratchi ◽  
Laxminarayanan Krishnan ◽  
Tel Rouse ◽  
Catherine Chou ◽  
Todd C. McDevitt ◽  
...  
Keyword(s):  
Bone Formation ◽  
Heterotopic Ossification ◽  
Bone Morphogenetic Protein ◽  
Spatial Localization ◽  
Bone Defects ◽  
Bone Morphogenetic Protein 2 ◽  
Morphogenetic Protein ◽  
Large Bone ◽  
Large Bone Defects

Supraphysiologic doses of bone morphogenetic protein-2 (BMP-2) are used clinically to promote bone formation in fracture nonunions, large bone defects, and spinal fusion. However, abnormal bone formation (i.e., heterotopic ossification) caused by rapid BMP-2 release from conventional collagen sponge scaffolds is a serious complication. We leveraged the strong affinity interactions between heparin microparticles (HMPs) and BMP-2 to improve protein delivery to bone defects. We first developed a computational model to investigate BMP-2–HMP interactions and demonstrated improved in vivo BMP-2 retention using HMPs. We then evaluated BMP-2–loaded HMPs as a treatment strategy for healing critically sized femoral defects in a rat model that displays heterotopic ossification with clinical BMP-2 doses (0.12 mg/kg body weight). HMPs increased BMP-2 retention in vivo, improving spatial localization of bone formation in large bone defects and reducing heterotopic ossification. Thus, HMPs provide a promising opportunity to improve the safety profile of scaffold-based BMP-2 delivery.

scholarly journals In Vivo Regeneration of Large Bone Defects by Cross-Linked Porous Hydrogel: A Pilot Study in Mice Combining Micro Tomography, Histological Analyses, Raman Spectroscopy and Synchrotron Infrared Imaging

Materials ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 4275
Author(s):  
Tetsuya Adachi ◽  
Francesco Boschetto ◽  
Nao Miyamoto ◽  
Toshiro Yamamoto ◽  
Elia Marin ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Bone Tissue ◽  
Bone Defects ◽  
Bone Diseases ◽  
Therapeutic Modality ◽  
3D Scaffold ◽  
Computed Tomography Scanning ◽  
Large Bone ◽  
Large Bone Defects

The transplantation of engineered three-dimensional (3D) bone graft substitutes is a viable approach to the regeneration of severe bone defects. For large bone defects, an appropriate 3D scaffold may be necessary to support and stimulate bone regeneration, even when a sufficient number of cells and cell cytokines are available. In this study, we evaluated the in vivo performance of a nanogel tectonic 3D scaffold specifically developed for bone tissue engineering, referred to as nanogel cross-linked porous-freeze-dry (NanoCliP-FD) gel. Samples were characterized by a combination of micro-computed tomography scanning, Raman spectroscopy, histological analyses, and synchrotron radiation–based Fourier transform infrared spectroscopy. NanoCliP-FD gel is a modified version of a previously developed nanogel cross-linked porous (NanoCliP) gel and was designed to achieve highly improved functionality in bone mineralization. Spectroscopic imaging of the bone tissue grown in vivo upon application of NanoCliP-FD gel enables an evaluation of bone quality and can be employed to judge the feasibility of NanoCliP-FD gel scaffolding as a therapeutic modality for bone diseases associated with large bone defects.

Fabrication of piezoelectric porous BaTiO3 scaffold to repair large segmental bone defect in sheep

2020 ◽  
Vol 35 (4-5) ◽  
pp. 544-552 ◽  
Author(s):  
Wenwen Liu ◽  
Di Yang ◽  
Xinghui Wei ◽  
Shuo Guo ◽  
Ning Wang ◽  
...  
Keyword(s):  
Electric Field ◽  
Bone Defect ◽  
Piezoelectric Effect ◽  
Bone Defects ◽  
Segmental Bone Defect ◽  
Segmental Bone ◽  
Large Bone ◽  
Large Bone Defects

Porous titanium scaffolds can provide sufficient mechanical support and bone growth space for large segmental bone defect repair. However, they fail to restore the physiological environment of bone tissue. Barium titanate (BaTiO3) is considered a smart material that can produce an electric field in response to dynamic force. Low-intensity pulsed ultrasound stimulation (LIPUS), as a kind of micromechanical wave, can not only promote bone repair but also induce BaTiO3 to generate an electric field. In our studies, BaTiO3 was coated on porous Ti6Al4V and LIPUS was externally applied to observe the influence of the piezoelectric effect on the repair of large bone defects in vitro and in vivo. The results show that the piezoelectric effect can effectively promote the osteogenic differentiation of bone marrow stromal cells (BMSCs) in vitro as well as bone formation and growth into implants in vivo. This study provides an optional alternative to the conventional porous Ti6Al4V scaffold with enhanced osteogenesis and osseointegration for the repair of large bone defects.

scholarly journals Factors related to large bone defects of bipolar lesions and a high number of instability episodes with anterior glenohumeral instability

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Noboru Matsumura ◽  
Kazuya Kaneda ◽  
Satoshi Oki ◽  
Hiroo Kimura ◽  
Taku Suzuki ◽  
...  
Keyword(s):  
Humeral Head ◽  
Glenohumeral Joint ◽  
Three Dimensional ◽  
Clinical Results ◽  
Bone Defects ◽  
Symptom Duration ◽  
Glenohumeral Instability ◽  
Explanatory Variables ◽  
Large Bone ◽  
Large Bone Defects

Abstract Background Significant bone defects are associated with poor clinical results after surgical stabilization in cases of glenohumeral instability. Although multiple factors are thought to adversely affect enlargement of bipolar bone loss and increased shoulder instability, these factors have not been sufficiently evaluated. The purpose of this study was to identify the factors related to greater bone defects and a higher number of instability episodes in patients with glenohumeral instability. Methods A total of 120 consecutive patients with symptomatic unilateral instability of the glenohumeral joint were retrospectively reviewed. Three-dimensional surface-rendered/registered models of bilateral glenoids and proximal humeri from computed tomography data were matched by software, and the volumes of bone defects identified in the glenoid and humeral head were assessed. After relationships between objective variables and explanatory variables were evaluated using bivariate analyses, factors related to large bone defects in the glenoid and humeral head and a high number of total instability episodes and self-irreducible dislocations greater than the respective 75th percentiles were evaluated using logistic regression analyses with significant variables on bivariate analyses. Results Larger humeral head defects (P < .001) and a higher number of total instability episodes (P = .032) were found to be factors related to large glenoid defects. On the other hand, male sex (P = .014), larger glenoid defects (P = .015), and larger number of self-irreducible dislocations (P = .027) were related to large humeral head bone defects. An increased number of total instability episodes was related to longer symptom duration (P = .001) and larger glenoid defects (P = .002), and an increased number of self-irreducible dislocations was related to larger humeral head defects (P = .007). Conclusions Whereas this study showed that bipolar lesions affect the amount of bone defects reciprocally, factors related to greater bone defects differed between the glenoid and the humeral head. Glenoid defects were related to the number of total instability episodes, whereas humeral head defects were related to the number of self-irreducible dislocations.

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