How Nanotechnology can Really Improve the Future of Orthopedic Implants and Scaffolds for Bone and Cartilage Defects

Background: Osteochondral allograft transplantation is 1 treatment option for focal articular cartilage defects of the knee. Large irregular defects, which can be treated using an oblong allograft or multiple overlapping allografts, increase the procedure’s technical complexity and may provide suboptimal cartilage and subchondral surface matching between donor grafts and recipient sites. Purpose: To quantify and compare cartilage and subchondral surface topography mismatch and cartilage step-off for oblong and overlapping allografts using a 3-dimensional simulation model. Study Design: Controlled laboratory study. Methods: Human cadaveric medial femoral hemicondyles (n = 12) underwent computed tomography and were segmented into cartilage and bone components using 3-dimensional reconstruction and modeling software. Segments were then exported into point-cloud models. Modeled defect sizes of 17 × 30 mm were created on each recipient hemicondyle. There were 2 types of donor allografts from each condyle utilized: overlapping and oblong. Grafts were virtually harvested and implanted to optimally align with the defect to provide minimal cartilage surface topography mismatch. Least mean squares distances were used to measure cartilage and subchondral surface topography mismatch and cartilage step-off. Results: Cartilage and subchondral topography mismatch for the overlapping allograft group was 0.27 ± 0.02 mm and 0.80 ± 0.19 mm, respectively. In comparison, the oblong allograft group had significantly increased cartilage (0.62 ± 0.43 mm; P < .001) and subchondral (1.49 ± 1.10 mm; P < .001) mismatch. Cartilage step-off was also found to be significantly increased in the oblong group compared with the overlapping group ( P < .001). In addition, overlapping allografts more reliably provided a significantly higher percentage of clinically acceptable (0.5- and 1-mm thresholds) cartilage surface topography matching (overlapping: 100% for both 0.5 and 1 mm; oblong: 90% for 1 mm and 56% for 0.5 mm; P < .001) and cartilage step-off (overlapping: 100% for both 0.5 and 1 mm; oblong: 86% for 1 mm and 12% for 0.5 mm; P < .001). Conclusion: This computer simulation study demonstrated improved topography matching and decreased cartilage step-off with overlapping osteochondral allografts compared with oblong osteochondral allografts when using grafts from donors that were not matched to the recipient condyle by size or radius of curvature. These findings suggest that overlapping allografts may be superior in treating large, irregular osteochondral defects involving the femoral condyles with regard to technique. Clinical Relevance: This study suggests that overlapping allografts may provide superior articular cartilage surface topography matching compared with oblong allografts and do so in a more reliable fashion. Surgeons may consider overlapping allografts over oblong allografts because of the increased ease of topography matching during placement.

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Dynamics of changes in the structural components of the mucosa and cartilage of the larynx of rats at the end of 28th and 35th days of experimental opioid exposure

OTORHINOLARYNGOLOGY 2-3(2) 2019 - OTORHINOLARYNGOLOGY ◽

10.37219/2528-8253-2021-4-79 ◽

2021 ◽

pp. 79-88

Author(s):

Khrystyna P. Ivasivka ◽

Evgeniy V. Paltov ◽

Zoryana Z. Masna ◽

Yuri Ya. Kryvko ◽

Maryana B. Cherkes

Keyword(s):

Mucous Membrane ◽

Structural Components ◽

Fundamental Study ◽

The Future ◽

And Cartilage

In our work we aimed to conduct a fundamental study of the process of morphological disorganization of the structural components of the mucous membrane and cartilage of the larynx at the end of the 28 and 35 days of experimental opioid effects at the microstructural level. This information in the future will allow to form a pathomorphological base, which will be used to compare the components of the mucous membrane and cartilage of the larynx in the norm with the dynamics of their changes as a result of experimental opioid effects at different times.

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Progress and Applications of Polyphosphate in Bone and Cartilage Regeneration

BioMed Research International ◽

10.1155/2019/5141204 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Yan Wang ◽

Min Li ◽

Pei Li ◽

Haijun Teng ◽

Dehong Fan ◽

...

Keyword(s):

Cartilage Regeneration ◽

High Energy ◽

Cartilage Defects ◽

Artificial Bone ◽

Cellular Mechanisms ◽

Inorganic Polyphosphate ◽

Morphogenetic Effects ◽

And Cartilage

Patients with bone and cartilage defects due to infection, tumors, and trauma are quite common. Repairing bone and cartilage defects is thus a major problem for clinicians. Autologous and artificial bone transplantations are associated with many challenges, such as limited materials and immune rejection. Bone and cartilage regeneration has become a popular research topic. Inorganic polyphosphate (polyP) is a widely occurring biopolymer with high-energy phosphoanhydride bonds that exists in organisms from bacteria to mammals. Much data indicate that polyP acts as a regulator of gene expression in bone and cartilage tissues and exerts morphogenetic effects on cells involved in bone and cartilage formation. Exposure of these cells to polyP leads to the increase of cytokines that promote the differentiation of mesenchymal stem cells into osteoblasts, accelerates the osteoblast mineralization process, and inhibits the differentiation of osteoclast precursors to functionally active osteoclasts. PolyP-based materials have been widely reported in in vivo and in vitro studies. This paper reviews the current cellular mechanisms and material applications of polyP in bone and cartilage regeneration.

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Recent Progress in 3D Printing of Elastic and High-Strength Hydrogels for the Treatment of Osteochondral and Cartilage Diseases

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2020.604814 ◽

2020 ◽

Vol 8 ◽

Author(s):

Wenli Dai ◽

Muyang Sun ◽

Xi Leng ◽

Xiaoqing Hu ◽

Yingfang Ao

Keyword(s):

Articular Cartilage ◽

3D Printing ◽

Recent Progress ◽

High Strength ◽

Cartilage Defects ◽

High Water Content ◽

Covalent Bonds ◽

Cartilage Diseases ◽

Articular Cartilage Defects ◽

And Cartilage

Despite considerable progress for the regenerative medicine, repair of full-thickness articular cartilage defects and osteochondral interface remains challenging. This low efficiency is largely due to the difficulties in recapitulating the stratified zonal architecture of articular cartilage and engineering complex gradients for bone-soft tissue interface. This has led to increased interest in three-dimensional (3D) printing technologies in the field of musculoskeletal tissue engineering. Printable and biocompatible hydrogels are attractive materials for 3D printing applications because they not only own high tunability and complexity, but also offer favorable biomimetic environments for live cells, such as porous structure, high water content, and bioactive molecule incorporation. However, conventional hydrogels are usually mechanically weak and brittle, which cannot reach the mechanical requirements for repair of articular cartilage defects and osteochondral interface. Therefore, the development of elastic and high-strength hydrogels for 3D printing in the repairment of cartilage defects and osteochondral interface is crucial. In this review, we summarized the recent progress in elastic and high-strength hydrogels for 3D printing and categorized them into six groups, namely ion bonds interactions, nanocomposites integrated in hydrogels, supramolecular guest–host interactions, hydrogen bonds interactions, dynamic covalent bonds interactions, and hydrophobic interactions. These 3D printed elastic and high-strength hydrogels may provide new insights for the treatment of osteochondral and cartilage diseases.

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Evolution of Autologous Chondrocyte Repair and Comparison to Other Cartilage Repair Techniques

BioMed Research International ◽

10.1155/2014/272481 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 65

Author(s):

Ashvin K. Dewan ◽

Matthew A. Gibson ◽

Jennifer H. Elisseeff ◽

Michael E. Trice

Keyword(s):

Cartilage Repair ◽

Autologous Chondrocyte Implantation ◽

Young Patients ◽

Cartilage Defects ◽

Chondral Defects ◽

Chondrocyte Implantation ◽

Osteochondral Grafting ◽

And Cartilage ◽

Autologous Chondrocyte ◽

Repair Techniques

Articular cartilage defects have been addressed using microfracture, abrasion chondroplasty, or osteochondral grafting, but these strategies do not generate tissue that adequately recapitulates native cartilage. During the past 25 years, promising new strategies using assorted scaffolds and cell sources to induce chondrocyte expansion have emerged. We reviewed the evolution of autologous chondrocyte implantation and compared it to other cartilage repair techniques.Methods. We searched PubMed from 1949 to 2014 for the keywords “autologous chondrocyte implantation” (ACI) and “cartilage repair” in clinical trials, meta-analyses, and review articles. We analyzed these articles, their bibliographies, our experience, and cartilage regeneration textbooks.Results. Microfracture, abrasion chondroplasty, osteochondral grafting, ACI, and autologous matrix-induced chondrogenesis are distinguishable by cell source (including chondrocytes and stem cells) and associated scaffolds (natural or synthetic, hydrogels or membranes). ACI seems to be as good as, if not better than, microfracture for repairing large chondral defects in a young patient’s knee as evaluated by multiple clinical indices and the quality of regenerated tissue.Conclusion. Although there is not enough evidence to determine the best repair technique, ACI is the most established cell-based treatment for full-thickness chondral defects in young patients.

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CARTILAGE REPAIR BY OSTEOCHONDRAL GRAFT IN THE KNEES OF PIGS — A HISTOLOGICAL STUDY

Journal of Musculoskeletal Research ◽

10.1142/s0218957700000112 ◽

2000 ◽

Vol 04 (02) ◽

pp. 135-143

Author(s):

Ching-Jen Wang ◽

Han-Shiang Chen ◽

Sheng-Ming Cheng ◽

Chris Y. C. Chen ◽

Hsuan-Ying Huang ◽

...

Keyword(s):

Bone Remodeling ◽

Histological Study ◽

Left Knee ◽

Host Tissue ◽

Cartilage Defects ◽

Osteochondral Graft ◽

Full Thickness ◽

Osteochondral Grafts ◽

The Right ◽

And Cartilage

Purpose: To investigate the mechanism of free autogenous osteochondral graft in full thickness cartilage defect in the knees of pigs aged three to four months old and weighing 8.5 to 11.5 kg, by histological examination. Methods: Full thickness cartilage defects were created on the medial femoral condyles of both knees. The defects on the right knee served as control study. The defects on the left knee were grafted with free autogenous osteochondral grafts. Biopsies were performed in 4, 8 and 12 weeks and the specimens were examined for predominant tissues, structure characteristics and cell changes as well as the healing of bone and cartilage between the graft and host tissue. Results: The control lesions showed extensive fibrous tissues with increased neovascularization, but no cartilage. With osteochondral grafts, bone remodeling took place in four weeks; and cartilage healing by direct bonding in approximately 12 weeks. There were transient degenerative changes of chondrocyte cellularity and morphology and increased neovascularization in four to eight weeks, which improved by 12 weeks. Conclusions: The mechanism of free autogenous osteochondral grafts started off with bone remodeling in as early as four weeks, which in turn provided better graft stability and promoted neovascularization and nutrition to the cartilage. The healing of hyaline cartilage by direct bonding to the host tissue took place in 12 weeks. There were transient interval changes of chondrocyte cellularity and morphology that warrant postoperative protection of the knees for 8 to 12 weeks.

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PATHOMORPHOLOGICAL CHARACTERISTICS OF CHANGES IN THE STRUCTURAL COMPONENTS OF THE MUCOSA AND CARTILAGE OF THE LARYNX OF RATS AT THE END OF THE SEVENTH DAY OF THE EXPERIMENTAL OPIOID EFFECT

Science Review ◽

10.31435/rsglobal_sr/30042021/7516 ◽

2021 ◽

Author(s):

Ivasivka K. P. ◽

Paltov E. V. ◽

Masna Z. Z.

Keyword(s):

Mucous Membrane ◽

Structural Components ◽

Fundamental Study ◽

The Future ◽

And Cartilage

In our work we aimed to conduct a fundamental study of the process of morphological disorganization of the structural components of the mucous membrane and cartilage of the larynx at the end of the seventh day of experimental opioid effects at the microstructural level. This information in the future will allow to form a pathomorphological base, which will be used to compare the components of the mucous membrane and cartilage of the larynx in the norm with the dynamics of their changes as a result of experimental opioid effects at different times.

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ULTRASTRUCTURAL CHARACTERISTICS OF THE LARYNGEAL MUCOSA AND CARTILAGE RAT IS NORMAL

World Science ◽

10.31435/rsglobal_ws/30072021/7635 ◽

2021 ◽

Author(s):

Ivasivka K. P.

Keyword(s):

Mucous Membrane ◽

Fundamental Study ◽

Laryngeal Cartilage ◽

Laryngeal Mucosa ◽

The Future ◽

Ultrastructural Characteristics ◽

And Cartilage

In our work, the aim was to conduct a fundamental study of the issue concerning the ultrastructural characteristics of the mucous membrane and cartilaginous corset of the rat larynx in the norm.This information in the future will make it possible to form a base that will be used to compare the components of the mucosa and laryngeal cartilage in the norm with the dynamics of their changes as a result of experimental opioid exposure.

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