19 EFFECT OF MINERALIZATION ON THE MATERIAL PROPERTIES OF ARTICULAR CARTILAGE IN THE RAT

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.

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8C-09 FEM estimation of material properties of articular cartilage by cylindrical indentation

The Proceedings of the Bioengineering Conference Annual Meeting of BED/JSME ◽

10.1299/jsmebio.2010.23.49 ◽

2011 ◽

Vol 2010.23 (0) ◽

pp. 49-50

Author(s):

Nobuo SAKAI ◽

Yuichiro HAGIHARA ◽

Tsukasa FURUSAWA ◽

Yoshinori SAWAE ◽

Teruo MURAKAMI

Keyword(s):

Articular Cartilage ◽

Material Properties

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Material properties of articular cartilage in the rabbit tibial plateau

Journal of Biomechanics ◽

10.1016/j.jbiomech.2005.07.017 ◽

2006 ◽

Vol 39 (12) ◽

pp. 2331-2337 ◽

Cited By ~ 39

Author(s):

Maria L. Roemhildt ◽

Kathryn M. Coughlin ◽

Glenn D. Peura ◽

Braden C. Fleming ◽

Bruce D. Beynnon

Keyword(s):

Articular Cartilage ◽

Material Properties ◽

Tibial Plateau

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Sensitivities of Medial Meniscal Motion and Deformation to Material Properties of Articular Cartilage, Meniscus and Meniscal Attachments Using Design of Experiments Methods

Journal of Biomechanical Engineering ◽

10.1115/1.2191077 ◽

2005 ◽

Vol 128 (3) ◽

pp. 399-408 ◽

Cited By ~ 57

Author(s):

Jiang Yao ◽

Paul D. Funkenbusch ◽

Jason Snibbe ◽

Mike Maloney ◽

Amy L. Lerner

Keyword(s):

Experimental Data ◽

Articular Cartilage ◽

Elastic Material ◽

Material Properties ◽

Cruciate Ligament ◽

Transverse Isotropy ◽

Experimental Studies ◽

Critical Material ◽

Isotropic Elastic Material ◽

Meniscal Attachments

This study investigated the role of the material properties assumed for articular cartilage, meniscus and meniscal attachments on the fit of a finite element model (FEM) to experimental data for meniscal motion and deformation due to an anterior tibial loading of 45N in the anterior cruciate ligament-deficient knee. Taguchi style L18 orthogonal arrays were used to identify the most significant factors for further examination. A central composite design was then employed to develop a mathematical model for predicting the fit of the FEM to the experimental data as a function of the material properties and to identify the material property selections that optimize the fit. The cartilage was modeled as isotropic elastic material, the meniscus was modeled as transversely isotropic elastic material, and meniscal horn and the peripheral attachments were modeled as noncompressive and nonlinear in tension spring elements. The ability of the FEM to reproduce the experimentally measured meniscal motion and deformation was most strongly dependent on the initial strain of the meniscal horn attachments (ε1H), the linear modulus of the meniscal peripheral attachments (EP) and the ratio of meniscal moduli in the circumferential and transverse directions (Eθ∕ER). Our study also successfully identified values for these critical material properties (ε1H=−5%, EP=5.6MPa, Eθ∕ER=20) to minimize the error in the FEM analysis of experimental results. This study illustrates the most important material properties for future experimental studies, and suggests that modeling work of meniscus, while retaining transverse isotropy, should also focus on the potential influence of nonlinear properties and inhomogeneity.

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Investigation Into the Biphasic Properties of a Hydrogel for Use in a Cushion Form Replacement Joint

Journal of Biomechanical Engineering ◽

10.1115/1.2798003 ◽

1998 ◽

Vol 120 (3) ◽

pp. 362-369 ◽

Cited By ~ 8

Author(s):

A. A. J. Goldsmith ◽

S. E. Clift

Keyword(s):

Articular Cartilage ◽

Material Properties ◽

Poisson’S Ratio ◽

Poisson's Ratio ◽

Biphasic Model ◽

Aggregate Modulus ◽

Curve Fit ◽

Potential Applications

A hydrogel with potential applications in the role of a cushion form replacement joint bearing surface material has been investigated. The material properties are required for further development and design studies and have not previously been quantified. Creep indentation experiments were therefore performed on samples of the hydrogel. The biphasic model developed by Mow and co-workers (Mak et al., 1987; Mow et al., 1989a) was used to curve-fit the experimental data to theoretical solutions in order to extract the three intrinsic biphasic material properties of the hydrogel (aggregate modulus, HA, Poisson’s ratio, νs, and permeability, k). Ranges of material properties were determined: aggregate modulus was calculated to be between 18.4 and 27.5 MPa, Poisson’s ratio 0.0–0.307, and permeability 0.012–7.27 × 10−17 m4/Ns. The hydrogel thus had a higher aggregate modulus than values published for natural normal articular cartilage, the Poisson’s ratios were similar to articular cartilage, and finally the hydrogel was found to be less permeable than articular cartilage. The determination of these values will facilitate further numerical analysis of the stress distribution in a cushion form replacement joint.

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Comparison Between the Hyperelastic Behavior of Fresh and Frozen Equine Articular Cartilage in Various Joints

Journal of Biomechanical Engineering ◽

10.1115/1.4044031 ◽

2019 ◽

Vol 142 (2) ◽

Author(s):

Hyeon Lee ◽

William D. Campbell ◽

Kelcie M. Theis ◽

Margaret E. Canning ◽

Hannah Y. Ennis ◽

...

Keyword(s):

Articular Cartilage ◽

Material Properties ◽

Statistical Models ◽

Solid Phase ◽

Material Constant ◽

Hyperelastic Material ◽

Aggregate Modulus ◽

Significant Difference ◽

Fluid Load ◽

Hyperelastic Model

Abstract Fresh and frozen cartilage samples of the fetlock, carpus, and stifle were collected from 12 deceased horses. Half were measured immediately following extraction, and half were frozen for seven days and then measured. Seven indentations (various normalized displacements) were implemented with an indention rate of 0.1 mm/s. Solid phase aggregate modulus (Es), hyperelastic material constant (α), and fluid load fraction (F′) of equine articular cartilage were assessed using the Ogden hyperelastic model. The properties were statistically compared in various joints (fetlock, carpus, and stifle), and between fresh and frozen samples using various statistical models. There was no statistical difference between the fetlock and carpus in the aggregate modulus (p = 0.5084), while both were significantly different from the stifle (fetlock: p = 0.0017 and carpus: p = 0.0406). For the hyperelastic material constant, no statistical differences between joints were observed (p = 0.3310). For the fluid load fraction, the fetlock and stifle comparison showed a difference (p = 0.0333), while the carpus was not different from the fetlock (p = 0.1563) or stifle (p = 0.3862). Comparison between the fresh and frozen articular cartilage demonstrated no significant difference among the joints in the three material properties: p = 0.9418, p = 0.7031, and p = 0.9313 for the aggregate modulus, the hyperelastic material constant, and the fluid load fraction, respectively.

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