Interstitial Fluid Pressurization During Confined Compression Cyclical Loading of Articular Cartilage

10.1114/1.239 ◽  
2000 ◽  
Vol 28 (2) ◽  
pp. 150-159 ◽  
Author(s):  
Michael A. Soltz ◽  
Gerard A. Ateshian
Keyword(s):  
Articular Cartilage ◽  
Interstitial Fluid ◽  
Confined Compression ◽  
Cyclical Loading ◽  
Fluid Pressurization

The Role of Interstitial Fluid Pressurization and Surface Porosities on the Boundary Friction of Articular Cartilage

1998 ◽  
Vol 120 (2) ◽  
pp. 241-248 ◽  
Author(s):  
G. A. Ateshian ◽  
Huiqun Wang ◽  
W. M. Lai
Keyword(s):  
Articular Cartilage ◽  
Friction Coefficient ◽  
Interstitial Fluid ◽  
Mathematical Formulation ◽  
Friction Model ◽  
Experimental Results ◽  
Boundary Friction ◽  
Confined Compression ◽  
Theoretical Formulation ◽  
Fluid Pressurization

Articular cartilage is the remarkable bearing material of diarthrodial joints. Experimental measurements of its friction coefficient under various configurations have demonstrated that it is load-dependent, velocity-dependent, and time-dependent, and it can vary from values as low as 0.002 to as high as 0.3 or greater. Yet, many studies have suggested that these frictional properties are not dependent upon the viscosity of synovial fluid. In this paper, a theoretical formulation of a boundary friction model for articular cartilage is described and verified directly against experimental results in the configuration of confined compression stress-relaxation. The mathematical formulation of the friction model can potentially explain many of the experimentally observed frictional responses in relation to the pressurization of the interstitial fluid inside cartilage during joint loading, and the equilibrium friction coefficient which prevails in the absence of such pressurization. In this proposed model, it is also hypothesized that surface porosities play a role in the regulation of the frictional response of cartilage. The good agreement between theoretical predictions and experimental results of this study provide support for the proposed boundary friction formulation.

Permeability of Human Glenohumeral Joint Cartilage

1999 ◽  
Author(s):  
Anna Stankiewicz ◽  
Gerard A. Ateshian ◽  
Louis U. Bigliani ◽  
Van C. Mow
Keyword(s):  
Mechanical Properties ◽  
Articular Cartilage ◽  
Interstitial Fluid ◽  
Glenohumeral Joint ◽  
Solid Matrix ◽  
Joint Cartilage ◽  
Frictional Drag ◽  
Diarthrodial Joints ◽  
Flow Through ◽  
Fluid Pressurization

Abstract The nearly frictionless lubrication in diarthrodial joints and load support within articular cartilage depends on its mechanical properties. It has been shown that the majority of applied loads on cartilage are supported by interstitial fluid pressurization (Ateshian et al., 1994) which results from the frictional drag of flow through the porous permeable solid matrix. The duration and magnitude of this pressurization are a function of the permeability of cartilage (Lai et al., 1981).

Direct Hydraulic Permeability Measurements of Agarose Hydrogels Used as Cell Scaffolds

1999 ◽  
Author(s):  
Michael A. Soltz ◽  
Anna Stankiewicz ◽  
Gerard Ateshian ◽  
Robert L. Mauck ◽  
Clark T. Hung
Keyword(s):  
Fluid Flow ◽  
Articular Cartilage ◽  
Interstitial Fluid ◽  
Convective Transport ◽  
Hydraulic Permeability ◽  
Interstitial Fluid Flow ◽  
Pass Through ◽  
Fluid Pressurization ◽  
First Time

Abstract The objective of this study was to determine the intrinsic hydraulic permeability of 2% agarose hydrogels. Two-percent agarose was chosen because it is a concentration typically used for encapsulation of chondrocytes in suspension cultures [3–5], Hydraulic permeability is a measure of the relative ease by which fluid can pass through a material. Importantly, it governs the level of interstitial fluid flow as well as the interstitial fluid pressurization that is generated in a material during loading. Fluid pressurization is the source of the unique load-bearing and lubrication properties of articular cartilage [1,17] and represents a major component of the in vivo chondrocyte environment. We have previously reported that 2% agarose hydrogels can support fluid pressurization, albeit to a significantly lesser degree than articular cartilage [18]. Interstitial fluid flow gives rise to convective transport of nutrients and ions [6,7] and matrix compaction [9] which may serve as important stimuli to chondrocytes. We report for the first time the strain-dependent hydraulic permeability of 2% agarose hydrogels.

Cartilage Interstitial Fluid Load Support in Unconfined Compression

2002 ◽  
Author(s):  
Seonghun Park ◽  
Ramaswamy Krishnan ◽  
Steven B. Nicoll ◽  
Gerard A. Ateshian
Keyword(s):  
Articular Cartilage ◽  
Interstitial Fluid ◽  
Articular Surface ◽  
Surface Zone ◽  
Unconfined Compression ◽  
Tissue Samples ◽  
Fluid Load ◽  
Tension And Compression ◽  
Fluid Pressurization ◽  
Theoretical Analyses

Under physiological conditions of loading, articular cartilage is subjected to both compressive strains, normal to the articular surface, and tensile strains, tangential to the articular surface. Previous studies have shown that articular cartilage exhibits a much higher modulus in tension than compression. Theoretical analyses have suggested that this tension-compression nonlinearity enhances the magnitude of interstitial fluid pressurization during loading in unconfined compression, above a theoretical threshold of 33% of the average applied stress. The first hypothesis of this experimental study is that the peak fluid load support in unconfined compression is significantly greater than the 33% theoretical limit predicted for porous permeable tissues modeled with equal moduli in tension and compression [1]. The second hypothesis is that the peak fluid load support is higher at the articular surface side of the tissue samples than near the deep zone, because the disparity between the tensile and compressive moduli is greater at the surface zone.

A Theoretical Formulation for Boundary Friction in Articular Cartilage

1997 ◽  
Vol 119 (1) ◽  
pp. 81-86 ◽  
Author(s):  
G. A. Ateshian
Keyword(s):  
Articular Cartilage ◽  
Interstitial Fluid ◽  
Mathematical Formulation ◽  
Friction Model ◽  
Time Dependent ◽  
Boundary Friction ◽  
Theoretical Formulation ◽  
Frictional Behavior ◽  
Fluid Pressurization ◽  
Effective Friction

A theoretical boundary friction model is proposed for predicting the frictional behavior of articular cartilage, including its time-dependent, velocity-dependent, and load-dependent responses. This theoretical model uses the framework of the biphasic theory for articular cartilage, and provides a mathematical formulation for the principle that interstitial fluid pressurization contributes significantly to reduction of the effective friction coefficient. Several examples of the application of this theory are provided, which demonstrate that a variety of experimentally observed cartilage frictional behaviors can now be theoretically predicted.

Sign in / Sign up

Export Citation Format

Share Document