scholarly journals Biphasic parameter identification of 3D scaffold-free cartilage transplants (SFCT) from stress relaxation compression tests using an optimized 3D FE-based method with tension-compression nonlinearity

2021 ◽  
Vol 7 (2) ◽  
pp. 355-358
Author(s):  
Thomas Reuter ◽  
Igor Ponomarev
Keyword(s):  
Articular Cartilage ◽  
Stress Relaxation ◽  
Tissue Characterization ◽  
Soft Tissues ◽  
Biomechanical Properties ◽  
Cartilage Defects ◽  
Fe Model ◽  
Compression Tests ◽  
3D Scaffold ◽  
Mesh Resolution

Abstract Cartilage constructs produced by SFCTtechnology provide promising opportunities to restore cartilage defects. Mechanical parameters of soft tissues are explicit markers for quantitative tissue characterization. In this study, we present a biphasic 3D-FE-based method to determine the biomechanical properties of SFCT from stress relaxation compression tests (ε = 20 %, t = 3400 s) whereby cartilaginous tissue is modeled as a biphasic material with tension-compression nonlinearity (BMTCN). The FE-model computation was optimized by exploiting the axial symmetry and mesh resolution. The R² of the fit results varies between 0.970 and 0.983. The Young’s and fiber modulus determined from SFCT are 37-times and 5-times lower than from native articular cartilage, respectively. Permeability, on the other hand, is 11-times higher than from native articular cartilage.

Comparison of biphasic material properties of equine articular cartilage estimated from stress relaxation and creep indentation tests

2021 ◽  
Vol 7 (2) ◽  
pp. 363-366
Author(s):  
Thomas Reuter ◽  
Christof Hurschler
Keyword(s):  
Articular Cartilage ◽  
Stress Relaxation ◽  
Material Properties ◽  
Soft Tissues ◽  
Sensitivity Analyses ◽  
Creep Model ◽  
Fe Model ◽  
Relaxation Model ◽  
Marquardt Algorithm ◽  
Indentation Tests

Abstract Mechanical parameters of hard and soft tissues are explicit markers for quantitative tissue characterization. In this study, we present a comparison of biphasic material properties of equine articular cartilage estimated from stress relaxation (ε = 6 %, t = 1000 s) and creep indentation tests (F = 0.1 N, t = 1000 s). A biphasic 3D-FE-based method is used to determine the biomechanical properties of equine articular cartilage. The FE-model computation was optimized by exploiting the axial symmetry and mesh resolution. Parameter identification was executed with the Levenberg- Marquardt-algorithm. Additionally, sensitivity analyses of the calculated biomechanical parameters were performed. Results show that the Young’s modulus E has the largest influence and the Poisson’s ratio of ν ≤ 0.1 is rather insensitive. The R² of the fit results varies between 0.882 and 0.974 (creep model) and between 0.695 and 0.930 (relaxation model). The averaged parameters E and k determined from the creep model yield higher values in comparison to the relaxation model. The differences can be traced back to the experimental settings and to the biphasic material model.

scholarly journals Comparison of biphasic material properties of equine articular cartilage from stress relaxation indentation tests with and without tension-compression nonlinearity

2018 ◽  
Vol 4 (1) ◽  
pp. 485-488
Author(s):  
Thomas Reuter ◽  
Christof Hurschler
Keyword(s):  
Articular Cartilage ◽  
Stress Relaxation ◽  
Material Properties ◽  
Collagen Matrix ◽  
Biomechanical Properties ◽  
Resolution Parameter ◽  
Marquardt Algorithm ◽  
Mesh Resolution ◽  
Indentation Tests ◽  
Order Of Magnitude

AbstractThe mechanical parameters of articular cartilage estimated from indentation tests depend on the constitutive model adopted to analyze the data. In this study, we present a 3D-FE-based method to determine the biomechanical properties of equine articular cartilage from stress relaxation indentation tests (ε = 6 %, t = 1000 s) whereby articular cartilage is modeled as a biphasic material without (BM) and with tension-compression nonlinearity (BMTCN). The FEmodel computation was optimized by exploiting the axial symmetry and mesh resolution. Parameter identification was executed with the Levenberg-Marquardt-algorithm. The R² of the fit results varies between 0.695 and 0.930 for the BMmodel and between 0.877 and 0.958 for the BMTCN-model. The differences of the R² occur from the more exact description of the initial stress relaxation behaviour by the fiber modulus from the BMTCN-model. The fiber modulus defines the collagen matrix of cartilage. Furthermore, for both models the determined values of Young’s modulus and permeability were in the same order of magnitude.

scholarly journals A composite scaffold of Wharton’s jelly and chondroitin sulphate loaded with human umbilical cord mesenchymal stem cells repairs articular cartilage defects in rat knee

2021 ◽  
Vol 32 (4) ◽  
Author(s):  
Zhong Li ◽  
Yikang Bi ◽  
Qi Wu ◽  
Chao Chen ◽  
Lu Zhou ◽  
...  
Keyword(s):  
Stem Cells ◽  
Articular Cartilage ◽  
Composite Scaffold ◽  
Biomechanical Properties ◽  
Cartilage Defects ◽  
Human Umbilical Cord ◽  
Composite Scaffolds ◽  
Articular Cartilage Defects

AbstractTo evaluate the performance of a composite scaffold of Wharton’s jelly (WJ) and chondroitin sulfate (CS) and the effect of the composite scaffold loaded with human umbilical cord mesenchymal stem cells (hUCMSCs) in repairing articular cartilage defects, two experiments were carried out. The in vitro experiments involved identification of the hUCMSCs, construction of the biomimetic composite scaffolds by the physical and chemical crosslinking of WJ and CS, and testing of the biomechanical properties of both the composite scaffold and the WJ scaffold. In the in vivo experiments, composite scaffolds loaded with hUCMSCs and WJ scaffolds loaded with hUCMSCs were applied to repair articular cartilage defects in the rat knee. Moreover, their repair effects were evaluated by the unaided eye, histological observations, and the immunogenicity of scaffolds and hUCMSCs. We found that in vitro, the Young’s modulus of the composite scaffold (WJ-CS) was higher than that of the WJ scaffold. In vivo, the composite scaffold loaded with hUCMSCs repaired rat cartilage defects better than did the WJ scaffold loaded with hUCMSCs. Both the scaffold and hUCMSCs showed low immunogenicity. These results demonstrate that the in vitro construction of a human-derived WJ-CS composite scaffold enhances the biomechanical properties of WJ and that the repair of knee cartilage defects in rats is better with the composite scaffold than with the single WJ scaffold if the scaffold is loaded with hUCMSCs.

scholarly journals Assessment of Native Human Articular Cartilage: A Biomechanical Protocol

Cartilage ◽  
2020 ◽  
pp. 194760352097324
Author(s):  
Wassif Kabir ◽  
Claudia Di Bella ◽  
Peter F.M. Choong ◽  
Cathal D. O’Connell
Keyword(s):  
Articular Cartilage ◽  
Poisson Ratio ◽  
Cartilage Tissue Engineering ◽  
Biomechanical Properties ◽  
Cartilage Tissue ◽  
Loading Frequency ◽  
Human Articular Cartilage ◽  
Compression Tests ◽  
Human Knee ◽  
Viscoelastic Parameters

Objectives Recapitulating the mechanical properties of articular cartilage (AC) is vital to facilitate the clinical translation of cartilage tissue engineering. Prior to evaluation of tissue-engineered constructs, it is fundamental to investigate the biomechanical properties of native AC under sudden, prolonged, and cyclic loads in a practical manner. However, previous studies have typically reported only the response of native AC to one or other of these loading regimes. We therefore developed a streamlined testing protocol to characterize the elastic and viscoelastic properties of human knee AC, generating values for several important parameters from the same sample. Design Human AC was harvested from macroscopically normal regions of distal femoral condyles of patients ( n = 3) undergoing total knee arthroplasty. Indentation and unconfined compression tests were conducted under physiological conditions (temperature 37 °C and pH 7.4) and testing parameters (strain rates and loading frequency) to assess elastic and viscoelastic parameters. Results The biomechanical properties obtained were as follows: Poisson ratio (0.4 ± 0.1), instantaneous modulus (52.14 ± 9.47 MPa) at a loading rate of 1 mm/s, Young’s modulus (1.03 ± 0.48 MPa), equilibrium modulus (7.48 ± 4.42 MPa), compressive modulus (10.60 ± 3.62 MPa), dynamic modulus (7.71 ± 4.62 MPa) at 1 Hz and loss factor (0.11 ± 0.02). Conclusions The measurements fell within the range of reported values for human knee AC biomechanics. To the authors’ knowledge this study is the first to report such a range of biomechanical properties for human distal femoral AC. This protocol may facilitate the assessment of tissue-engineered composites for their functionality and biomechanical similarity to native AC prior to clinical trials.

Study on Polyvinyl Alcohol Hydrogel Materials for Improving the Performance of Artificial Articular Cartilage

2013 ◽  
Vol 703 ◽  
pp. 29-32 ◽  
Author(s):  
Hou Jiang Yuan ◽  
Zhou Jian Wei ◽  
Xia Zhen Yu
Keyword(s):  
Articular Cartilage ◽  
Polyvinyl Alcohol ◽  
Impact Force ◽  
Biomechanical Properties ◽  
Research Progress ◽  
Cartilage Defects ◽  
Human Articular Cartilage ◽  
The Impact ◽  
Articular Cartilage Defects

Polyvinyl alcohol hydrogel has compatibility and biomechanical properties of human articular cartilage similar and good biological. The implantation in the human body can replace part of articular cartilage, which plays the role of bearing and alleviate the impact force. It has the prospect of clinical application. This paper introduces the research progress of polyvinyl alcohol hydro-gel materials. And compared with the characteristics of articular cartilage, clarify the possibility of repair of articular cartilage defects of the materials.

scholarly journals Microfracture Arthroscopy Efficacy In Treatment Of Articular Cartilage Insult Of Knee

2018 ◽  
Vol 14 (1) ◽  
pp. 24-28
Author(s):  
Mohamed Baqir Alshara
Keyword(s):  
Articular Cartilage ◽  
Arthroscopic Surgery ◽  
Biomechanical Properties ◽  
Cross Sectional Study ◽  
Cartilage Defects ◽  
Sectional Study ◽  
Degenerative Arthritis ◽  
Cross Sectional ◽  
Orthopedic Surgeons ◽  
Articular Cartilage Defects

Background: The treatment of articular cartilage defects is one of the most clinical challeng for orthopedic surgeons. Articular cartilage is a highly organized tissue with complex biomechanical properties and substantial durability. However, it has a poor ability for healing, and damage from trauma or degeneration can result in morbidity and functional impairment. debilitating joint pain, dysfunction, and degenerative arthritis                                                                           Objectives: The purpose of study is to show effectiveness of micro fracture arthroscopy as a method of treatment for such problem . Type of the study: Cross-sectional study.                     Methods: Arthroscopic surgery was done to 52 patients who complain of knee pain limping and show clinical or radiological evidence of cartilaginous injury and we used arthroscopic micro fracture technique for those patient who have injury of no more than4cm2 then we instruct patient to not put any weight over knee  for 2-3 months and followed clinically according to Lyshlom scor and by MRI and some of them by second look arthroscopy to assess the healing. Results: Fifty two patients under go micro fracture arthroscopy . Thirty four patients (65.4%) reported good or excellent subjective results  , thirteen patients (25%) had fair knee function, and only five patients  (9.6%) reported poor result Conclusions: Micro fracture arthroscopy is a   cheap effective method for repairing cartilaginous lesion .                                            

Removal of Sulfated Glycosaminoglycans Has a Differential Effect on Permeability of Bovine Articular Cartilage as Measured by Direct Permeation and Stress Relaxation

2009 ◽  
Author(s):  
Heath B. Henninger ◽  
Clayton J. Underwood ◽  
Gerard A. Ateshian ◽  
Jeffrey A. Weiss
Keyword(s):  
Articular Cartilage ◽  
Stress Relaxation ◽  
Soft Tissues ◽  
Water Movement ◽  
Experimental Treatment ◽  
Test Methods ◽  
Confined Compression ◽  
Interstitial Fluid Flow ◽  
Bovine Articular Cartilage ◽  
The Impact

Permeability is defined as the ability of a fluid to pass through a porous medium. The ease of water movement is a determinant of the interstitial fluid flow-dependent viscoelastic properties of hydrated soft tissues and also modulates transport of solutes. For articular cartilage, permeability has been quantified directly via permeation experiments and indirectly by analyzing the data from stress relaxation testing under confined compression. It is unclear whether these different methods result in consistent measurements. This further complicates quantification of the effect of an experimental treatment on permeability such as the removal of sulfated glycosaminoglycans (GAGs) [1, 2]. The objective of this study was to elucidate the impact of sulfated GAGs on the permeability of articular cartilage using direct permeation versus stress relaxation testing, and to assess any differences in permeability calculated from the two test methods.

scholarly journals Articular cartilage tissue engineering with stem cells implanted onto nanoscaffolds and platelet-rich plasma

2017 ◽  
Vol 3 (3) ◽  
pp. 322
Author(s):  
Hadeer A. Abbassy ◽  
Laila M. Montaser ◽  
Sherin M. Fawzy
Keyword(s):  
Tissue Engineering ◽  
Stem Cells ◽  
Articular Cartilage ◽  
Soft Tissues ◽  
Platelet Rich Plasma ◽  
Cartilage Tissue Engineering ◽  
Cartilage Regeneration ◽  
Cartilage Tissue ◽  
Cartilage Defects ◽  
Great Promise

<p class="abstract">Musculoskeletal medicine targets both cartilage regeneration and healing of soft tissues. Articular cartilage repair and regeneration is primarily considered to be due to its poor regenerative properties. Cartilage defects due to joint injury, aging, or osteoarthritis have low self-repair ability thus they are most often irreversible as well as being a major cause of joint pain and chronic disability. Unfortunately, current methods do not seamlessly restore hyaline cartilage and may lead to the formation of fibro- or continue hypertrophic cartilage. Deficiency of efficient modalities of therapy has invited research to combine stem cells, scaffold materials and environmental factors through tissue engineering. Articular cartilage tissue engineering aims to repair, regenerate, and hence improve the function of injured or diseased cartilage. This holds great potential and has evoked intense interest in improving cartilage therapy. Platelet-rich plasma (PRP) and/or stem cells may be influential for tissue repair as well as cartilage regenerative processes.  A great promise to advance current cartilage therapies toward achieving a consistently successful modality has been held for addressing cartilage afflictions. The use of stem cells, novel biologically inspired scaffolds and, emerging nanotechnology may be the best way to reach this objective via tissue engineering. A current and emergent approach in the field of cartilage tissue engineering is explained in this review for specific application. In the future, the development of new strategies using stem cells seeded in scaffolds and the culture medium supplemented with growth factors could improve the quality of the newly formed cartilage<span lang="EN-IN">.</span></p>

scholarly journals Biphasic parameter identification of equine articular cartilage from creep indentation data using an optimized 3D FE-based method

2018 ◽  
Vol 4 (1) ◽  
pp. 481-484
Author(s):  
Thomas Reuter ◽  
Christof Hurschler
Keyword(s):  
Articular Cartilage ◽  
Parameter Identification ◽  
Young’S Modulus ◽  
Poisson’S Ratio ◽  
Soft Tissues ◽  
Young's Modulus ◽  
Poisson's Ratio ◽  
Sensitivity Analyses ◽  
Fe Model ◽  
Marquardt Algorithm

AbstractMechanical parameters of hard and soft tissues are explicit markers for quantitative tissue characterization. In this study, we present a biphasic 3D-FE-based method to determine the biomechanical properties of equine articular cartilage from creep indentation tests (F = 0.1 N, t = 1000 s). The FE-model computation was optimized by exploiting the axial symmetry and mesh resolution. Parameter identification was executed with the Levenberg-Marquardt-algorithm. Additionally, sensitivity analyses of the calculated biomechanical parameters were performed. Results show that the Young’s modulus has the largest influence and the Poisson’s ratio of ν ≤ 0.1 is rather insensitive. The R² of the fit results varies between 0.882 and 0.974. The determined values for the Young’s modulus were 0.806 ± 0.093 MPa, the Poisson’s ratio 0.03 ± 0.06 and the permeability 0.012 ± 0.002 mm4/Ns. Future work will deal with mathematical extensions of the biphasic 3D-FE-model.

Non-Linear Model for Compression Tests on Articular Cartilage

2015 ◽  
Vol 137 (7) ◽  
Author(s):  
Alfio Grillo ◽  
Amr Guaily ◽  
Chiara Giverso ◽  
Salvatore Federico
Keyword(s):  
Experimental Data ◽  
Articular Cartilage ◽  
Hydraulic Properties ◽  
Soft Tissues ◽  
Homogeneous Model ◽  
Compression Tests ◽  
Confined Compression ◽  
Benchmark Tests ◽  
Non Linear ◽  
Biphasic Systems

Hydrated soft tissues, such as articular cartilage, are often modeled as biphasic systems with individually incompressible solid and fluid phases, and biphasic models are employed to fit experimental data in order to determine the mechanical and hydraulic properties of the tissues. Two of the most common experimental setups are confined and unconfined compression. Analytical solutions exist for the unconfined case with the linear, isotropic, homogeneous model of articular cartilage, and for the confined case with the non-linear, isotropic, homogeneous model. The aim of this contribution is to provide an easily implementable numerical tool to determine a solution to the governing differential equations of (homogeneous and isotropic) unconfined and (inhomogeneous and isotropic) confined compression under large deformations. The large-deformation governing equations are reduced to equivalent diffusive equations, which are then solved by means of finite difference (FD) methods. The solution strategy proposed here could be used to generate benchmark tests for validating complex user-defined material models within finite element (FE) implementations, and for determining the tissue's mechanical and hydraulic properties from experimental data.

Sign in / Sign up

Export Citation Format

Share Document