Effect of Anisotropic Permeability of the Superficial Layer on the Frictional Property in Articular Cartilage

2013 ◽  
Author(s):  
Kyuichiro Imade ◽  
Hiromichi Fujie
Keyword(s):  
Articular Cartilage ◽  
Hydrodynamic Lubrication ◽  
Articular Surface ◽  
Compressive Strain ◽  
Electron Microscopic Observation ◽  
Superficial Layer ◽  
Frictional Property ◽  
Hydraulic Permeability ◽  
Electron Microscopic ◽  
Biphasic Model

Articular cartilage has a significant lubrication property that has been explained in previous studies by many theories including mixed lubrication, hydrodynamic lubrication, surface gel hydration lubrication, biphasic theory, and so on. However the mechanism of continuously low friction in articular cartilage still remains unclear. Reynaud and Quinn indicated that the hydraulic permeability was significantly anisotropic under compressive strain; the tangential permeability becomes lower than the normal permeability under compression [1]. Meanwhile scanning electron microscopic observation indicated that the superficial layer of articular surface was consisted of close-packed collagen fibers aligning parallel with articular surface and tangling each other in normal cartilage (Fig. 1). It is, therefore, suggested that the permeability is extremely low in the tangential direction when subjected to compressive strain. We have a hypothesis that the unique structure and properties in the articular cartilage superficial layer may improve the lubrication properties [2]. Therefore, we performed an analytical study using a fiber-reinforced poroelastic biphasic model to determine the effect of lateral permeability reduction in the superficial layer on the frictional property of articular cartilage.

Light Microscopic, Immunohistochemical, and Electron Microscopic Features of Amyloid Arthropathy in Chickens

1997 ◽  
Vol 34 (4) ◽  
pp. 271-278 ◽  
Author(s):  
N. H. M. T. Peperkamp ◽  
W. J. M. Landman ◽  
P. C. J. Tooten ◽  
A. Ultee ◽  
W. F. Voorhout ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Enterococcus Faecalis ◽  
Amyloid Fibrils ◽  
Superficial Layer ◽  
Immunogold Electron Microscopy ◽  
Amyloid Formation ◽  
Electron Microscopic ◽  
Amyloid A ◽  
Amyloid Deposits ◽  
Amyloid Arthropathy

Amyloid arthropathy has been recently recognized as a spontaneous syndrome in chickens. Predominantly, femorotibial and tarsometatarsal joints were affected, showing (peri) articular orange amyloid deposits. Immunohistochemical evaluation revealed the amyloid to be of the reactive type. Induction of amyloid arthropathy in chickens was carried out using a single intravenous injection of Enterococcus faecalis cultures. In the naturally occurring and the induced cases, amyloid deposits were found in the hypertrophic synovial villi and in the articular cartilage, particularly in the superficial layer and in the nutritional blood vessel walls. Highly sulfated glycosaminoglycans (GAGs) were found in the amyloid deposits. Ultrastructurally, bundles of amyloid fibrils were seen in invaginations of synoviocytes and chondrocytes. Immunogold electron microscopy failed to reveal signs of intracellular amyloid formation. The predilection site for amyloid deposition in the major leg joints of the chickens with reactive amyloid could be explained by the arthritic condition caused by Enterococcus faecalis bacteriaemia. The polyarthritis triggers hepatic acute phase protein synthesis and increases the vascular serum amyloid A (SAA) supply to the joint. Inflammatory and degenerative changes in the articular cartilage and adjoining tissues result in an increase of highly sulphated GAGs, which are considered to enhance deposition of SAA as amyloid.

Mechanical anisotropy of the human knee articular cartilage in compression

2003 ◽  
Vol 217 (3) ◽  
pp. 215-219 ◽  
Author(s):  
J S Jurvelin ◽  
M D Buschmann ◽  
E B Hunziker
Keyword(s):  
Articular Cartilage ◽  
Poisson’S Ratio ◽  
Articular Surface ◽  
Mechanical Anisotropy ◽  
Poisson's Ratio ◽  
Hydraulic Permeability ◽  
Compression Tests ◽  
Direction Parallel ◽  
Anisotropic Mechanical Properties ◽  
Femoral Groove

Articular cartilage exhibits anisotropic mechanical properties when subjected to tension. However, mechanical anisotropy of mature cartilage in compression is poorly known. In this study, both confined and unconfined compression tests of cylindrical cartilage discs, taken from the adult human patello-femoral groove and cut either perpendicular (normal disc) or parallel (tangential disc) to the articular surface, were utilized to determine possible anisotropy in Young's modulus, E, aggregate modulus, Ha, Poisson's ratio, v and hydraulic permeability, k, of articular cartilage. The results indicated that Ha was significantly higher in the direction parallel to the articular surface as compared with the direction perpendicular to the surface ( Ha = 1.237 ± 0.486 MPa versus Ha = 0.845 ± 0.383 MPa, p = 0.017, n = 10). The values of Poisson's ratio were similar, 0.158 ± 0.148 for normal discs compared with 0.180 ± 0.046 for tangential discs. Analysis using the linear biphasic model revealed that the decrease of permeability during the offset compression of 0–20 per cent was higher ( p = 0.015, n = 10) in normal (from 25.5 × 10− 15 to 1.8 × 10−15 m4/N s) than in tangential (from 12.3 × 10− 15 to 1.3 × 10− 15 m4/N s) discs. Based on the results, it is concluded that the mechanical characteristics of adult femoral groove articular cartilage are anisotropic also during compression. Anisotropy during compression may be essential for normal cartilage function. This property has to be considered when developing advanced theoretical models for cartilage biomechanics.

Unconfined Compression of Articular Cartilage: Nonlinear Behavior and Comparison With a Fibril-Reinforced Biphasic Model

1999 ◽  
Vol 122 (2) ◽  
pp. 189-195 ◽  
Author(s):  
M. Fortin ◽  
J. Soulhat ◽  
A. Shirazi-Adl ◽  
E. B. Hunziker ◽  
M. D. Buschmann
Keyword(s):  
Articular Cartilage ◽  
Mechanical Behavior ◽  
Small Amplitude ◽  
Dynamic Stiffness ◽  
Scaling Law ◽  
Nonlinear Behavior ◽  
Hydraulic Permeability ◽  
Unconfined Compression ◽  
Biphasic Model ◽  
Strain Dependent

Mechanical behavior of articular cartilage was characterized in unconfined compression to delineate regimes of linear and nonlinear behavior, to investigate the ability of a fibril-reinforced biphasic model to describe measurements, and to test the prediction of biphasic and poroelastic models that tissue dimensions alter tissue stiffness through a specific scaling law for time and frequency. Disks of full-thickness adult articular cartilage from bovine humeral heads were subjected to successive applications of small-amplitude ramp compressions cumulating to a 10 percent compression offset where a series of sinusoidal and ramp compression and ramp release displacements were superposed. We found all equilibrium behavior (up to 10 percent axial compression offset) to be linear, while most nonequilibrium behavior was nonlinear, with the exception of small-amplitude ramp compressions applied from the same compression offset. Observed nonlinear behavior included compression-offset-dependent stiffening of the transient response to ramp compression, nonlinear maintenance of compressive stress during release from a prescribed offset, and a nonlinear reduction in dynamic stiffness with increasing amplitudes of sinusoidal compression. The fibril-reinforced biphasic model was able to describe stress relaxation response to ramp compression, including the high ratio of peak to equilibrium load. However, compression offset-dependent stiffening appeared to suggest strain-dependent parameters involving strain-dependent fibril network stiffness and strain-dependent hydraulic permeability. Finally, testing of disks of different diameters and rescaling of the frequency according to the rule prescribed by current biphasic and poroelastic models (rescaling with respect to the sample’s radius squared) reasonably confirmed the validity of that scaling rule. The overall results of this study support several aspects of current theoretical models of articular cartilage mechanical behavior, motivate further experimental characterization, and suggest the inclusion of specific nonlinear behaviors to models. [S0148-0731(00)00702-0]

The Micro-Mechanical Behavior of Articular Cartilage under Continuous Sliding Load

2013 ◽  
Vol 395-396 ◽  
pp. 654-657
Author(s):  
Peng Peng Xiao ◽  
Li Lan Gao ◽  
Zhi Dong Liu ◽  
Chun Qiu Zhang
Keyword(s):  
Articular Cartilage ◽  
Connective Tissue ◽  
Deep Layer ◽  
Compressive Strain ◽  
Middle Layer ◽  
Superficial Layer ◽  
Image Correlation ◽  
Daily Activities ◽  
Normal Displacement ◽  
Dic Technique

As a viscoelastic and nonlinear connective tissue, articular cartilage bears continuous sliding load in the daily activities. The optimized digital image correlation (DIC) technique was applied to investigate the effect of sliding rate and compressive strain on the normal displacement of different layers in pig articular cartilage under sliding load. The normal displacements of different layers in cartilage increase gradually with sliding going on with given sliding rate and compressive strain. Experiments showed that the normal displacement of superficial layer is the largest, the normal displacement of deep layer is the smallest and the normal displacement of middle layer is between superficial layer and deep layer, and found that the normal displacements of different layers in cartilage increase with increasing compressive strains, but decrease with increasing sliding rates. The normal displacement of different layers are different under continuous sliding load.

scholarly journals Modeling of Neutral Solute Transport in a Dynamically Loaded Porous Permeable Gel: Implications for Articular Cartilage Biosynthesis and Tissue Engineering

2003 ◽  
Vol 125 (5) ◽  
pp. 602-614 ◽  
Author(s):  
Robert L. Mauck ◽  
Clark T. Hung ◽  
Gerard A. Ateshian
Keyword(s):  
Articular Cartilage ◽  
Solute Transport ◽  
Dynamic Loading ◽  
Interstitial Fluid ◽  
Articular Surface ◽  
Compressive Strain ◽  
Convective Transport ◽  
Solid Matrix ◽  
Bathing Solution ◽  
Loading Frequency

A primary mechanism of solute transport in articular cartilage is believed to occur through passive diffusion across the articular surface, but cyclical loading has been shown experimentally to enhance the transport of large solutes. The objective of this study is to examine the effect of dynamic loading within a theoretical context, and to investigate the circumstances under which convective transport induced by dynamic loading might supplement diffusive transport. The theory of incompressible mixtures was used to model the tissue (gel) as a mixture of a gel solid matrix (extracellular matrix/scaffold), and two fluid phases (interstitial fluid solvent and neutral solute), to solve the problem of solute transport through the lateral surface of a cylindrical sample loaded dynamically in unconfined compression with frictionless impermeable platens in a bathing solution containing an excess of solute. The resulting equations are governed by nondimensional parameters, the most significant of which are the ratio of the diffusive velocity of the interstitial fluid in the gel to the solute diffusivity in the gel Rg, the ratio of actual to ideal solute diffusive velocities inside the gel Rd, the ratio of loading frequency to the characteristic frequency of the gel f^, and the compressive strain amplitude ε0. Results show that when Rg>1,Rd<1, and f^>1, dynamic loading can significantly enhance solute transport into the gel, and that this effect is enhanced as ε0 increases. Based on representative material properties of cartilage and agarose gels, and diffusivities of various solutes in these gels, it is found that the ranges Rg>1,Rd<1 correspond to large solutes, whereas f^>1 is in the range of physiological loading frequencies. These theoretical predictions are thus in agreement with the limited experimental data available in the literature. The results of this study apply to any porous hydrated tissue or material, and it is therefore plausible to hypothesize that dynamic loading may serve to enhance solute transport in a variety of physiological processes.

Deformation-induced structural transformation leading to compressive plasticity in Zr65Al7.5Ni10Cu12.5M5 (M = Nb, Pd) glassy alloys

2010 ◽  
Vol 25 (6) ◽  
pp. 1149-1158 ◽  
Author(s):  
Albertus D. Setyawan ◽  
Junji Saida ◽  
Hidemi Kato ◽  
Mitsuhide Matsushita ◽  
Akihisa Inoue
Keyword(s):  
Compressive Strain ◽  
Electron Microscopic Observation ◽  
Primary Crystallization ◽  
Supercooled Liquid ◽  
Icosahedral Phase ◽  
Electron Microscopic ◽  
Glassy Alloys ◽  
Transmission Electron ◽  
Transmission Electron Microscopic Observation

Zr65Al7.5Ni10Cu12.5Nb5 glass was found to exhibit a large plastic compressive strain of over 10% and the property was suggested to be due to deformation-induced nanocrystallization. A transmission electron microscopic observation, however, only revealed obscure ordered clusters with a size of ˜2 nm in the fracture surface of a deformed sample, instead of well-identified crystals as previously reported for the Zr–Al–Ni–Cu–Pd system. This phenomenon is suggested to correlate with the higher viscosity of supercooled liquid and the slower grain growth of icosahedral phase during primary crystallization in the Zr65Al7.5Ni10Cu12.5Nb5 compared to those in the Zr65Al7.5Ni10Cu12.5Pd5 alloy. The role of the deformation-induced nanoclusters on the enhanced compressive plasticity was discussed.

Articular Cartilage Biomechanics Modeled via an Intrinsically Compressible Biphasic Model: Implications and Deviations From an Incompressible Biphasic Approach

2013 ◽  
Author(s):  
Francesco Travascio ◽  
Roberto Serpieri ◽  
Shihab Asfour
Keyword(s):  
Articular Cartilage ◽  
Experimental Testing ◽  
Solid Matrix ◽  
Hydraulic Permeability ◽  
Theoretical Frameworks ◽  
Theoretical Formulation ◽  
New Model ◽  
Biphasic Model ◽  
Testing Procedures ◽  
Cartilage Biomechanics

Biphasic continuum models have been extensively deployed for modeling macroscopic articular cartilage biomechanics [1,2]. This consolidated theoretical approach schematizes tissue as a mixture of an elastic solid matrix embedded in a fluid phase. In physiological conditions, intrinsic compressibility of each phase is very limited when compared to the whole tissue macroscopic counterpart. Based on such experimental evidence, intrinsic phase compressibility is generally reasonably neglected [3]. Hence, traditionally, cartilage biomechanics models have been developed on the basis of incompressible biphasic formulations [3–5], often referred to as Incompressible Theories of Mixtures (ITM). Alternatively, a more general biphasic model for cartilage biomechanics, accounting for full intrinsic compressibility of phases, may be considered. A consistent theoretical formulation of this type has been recently made available [6,7], hereby referred to as Theory of Microscopically Compressible Porous Media (TMCPM). In the present contribution, a new model for articular cartilage biomechanics, based on TMCPM, was developed. Predictions of this new model, and its deviations from a traditional ITM approach were studied. In particular, deviations between compressible and incompressible theoretical frameworks were investigated with a specific focus on the repercussions on models’ capability of characterizing fundamental tissue properties, such as hydraulic permeability, via established experimental testing procedures.

Study on Loading Rate-Dependent Property of Different Layers in Articular Cartilage Based on ABAQUS

2013 ◽  
Vol 395-396 ◽  
pp. 650-653 ◽  
Author(s):  
Zhi Dong Liu ◽  
Li Lan Gao ◽  
Bao Shan Xu ◽  
Xi Zheng Zhang ◽  
Chun Qiu Zhang
Keyword(s):  
Articular Cartilage ◽  
Loading Rate ◽  
Deep Layer ◽  
Compressive Strain ◽  
Biomechanical Model ◽  
Maximum Flow ◽  
Middle Layer ◽  
Superficial Layer ◽  
Loading Rates ◽  
Rate Dependent

A new biomechanical model of articular cartilage was developed using ABAQUS to investigate the mechanical properties of different layers under different loading rates. It is found that the compressive strain of superficial layer is the largest, the compressive strain of deep layer is the smallest and the compressive strain of middle layer is between the superficial and deep layer under constant loading rate. The compressive strains of different layers increase with increasing loading rates. At the beginning of loading, fluid flows mainly in the superficial layer and flows into the middle and deep layer with the increasing time and the position of the maximum flow moves downward. Void ratio also increases with the loading time.

Influence of proteoglycan contents and of tissue hydration on the frictional characteristics of articular cartilage

2005 ◽  
Vol 219 (3) ◽  
pp. 175-182 ◽  
Author(s):  
M H Naka ◽  
Y Morita ◽  
K Ikeuchi
Keyword(s):  
Articular Cartilage ◽  
Water Content ◽  
Articular Surface ◽  
Superficial Layer ◽  
Low Friction ◽  
Cartilage Surface ◽  
Intact Condition ◽  
Measured Water ◽  
Femoral Condyles

In this work, the hypothesis that water content and substances present on the articular surface play an important role in lubrication through the formation of a layer with a high content of water on the articular surface is analysed. The hydrophilic properties of proteoglycans exposed at the articular surface and hydration of tissue are the main responsible factors for the formation of this layer. The role of the articular surface in the frictional characteristics of articular cartilage was examined using specimens (femoral condyles of pigs) with intact and wiped surfaces tested in intermittent friction tests. Results indicated that the intact condition presented low friction in comparison with the wiped condition. The measured water loss of the articular cartilage after sliding and loading indicated a gradual decrease in the water content as the time evolved, and rehydration was observed after the submersion of unloaded specimens in the saline bath solution. Micrographic analyses indicated the presence of a layer covering the articular surface, and histological analyses indicated the presence of proteoglycans in this superficial layer. The hydration of the cartilage surface layer and proteoglycan in this layer influence lubrication.

Sign in / Sign up

Export Citation Format

Share Document