Papers by Keyword: Synovial Fluid

Abstract: This paper deals with synovial joints which are characterized by their large degree of motion. In synovial joints, magnetic field in addition to electric field is added to disperse the nutrients from the synovial fluid to cartilage by considering both BJ and BJR conditions. The governing equation of the physical model is solved analytically and computations are carried out for the parameters involved in the system under different boundary conditions. The obtained computational results indicate that a drastic improvement can be found for the efficiency of artificial joints with combined effects of electric and magnetic fields on electrohydrodynamic dispersion of biological bearings.

Abstract: Joint diseases represent a major health problem because they evolve towards the wear of cartilage for which no treatment is really effective. The difficulties in identifying the causes of these diseases are related to the biochemical and structural complexity of synovial fluid that allow cartilage lubrication. Thereby, recent studies show that synovial fluid contains micro-vesicles filled with a glycoprotein gel (hyaluronic acid and protein) surrounded by stacks of lipid bilayers which gives it excellent lubricating properties [1]. On the other side, this stable structure in vivo, becomes unstable in the ex vivo conditions. In this context, the study aims to tests the lubricating properties of synovial fluid constituents in order to identify their role on the tribological behavior of synovial joints and to develop a biomimetic synovial fluid using self-assembly of polyelectrolytes in order to stabilize the ex vivo structure for the potential therapeutic synovial fluid substitutes.Our results show that the new synthetized polysaccharides influence the friction coefficient, the stability and the wear of lipids bilayers, providing lubricating properties superior to synovial fluid biological constituents. In addition, their capacity to be structured in micro-spheres and included in lipid micro-vesicles indicates them as good biomimetic lubricants. This will allow a longer stability of synovial fluid substitutes in ex-vivo conditions in order to achieve the best lubricating properties and to improve the joint diseases treatment.

Abstract: Engineers, biologists and surgeons face a special task when they design procedures, components and systems to replace damaged tissues beyond any limits, caused by disease or trauma. It has been proven that titanium and its alloys have an excellent biocompatibility, that’s why many studies have been made on them, in order to enhance their biomedical applicability. In this paper, the wear behavior of two new titanium alloys, Ti12Mo and Ti25Nb25Ta , have been tested in biological conditions

Abstract: The purpose of this research was to study the synovial fluid diffusion behavior involved in articular cartilage and evaluation of some parameters, which affecting the cartilage degeneration, such as the porosity, surface permeability, fluid concentration and etc. For the analysis, it was to implement the triphasic theory into a mathematical model and a commercial finite element method to solved practical problems in cartilage mechanics. The experimental results of confined compression of articular cartilage were found that the factors affecting to fluid diffusion in cartilage were the surface permeability, the porosity of structure, the change of solute concentration and dynamic loading on articular cartilage.

Abstract: The calf serum solution was defined as the international standard lubricant for wear characterization of artificial hip joints. It is, however, known that its composition varies according to age, manufacturing processes or production areas of bovine cattle, and that the difference in composition has large effect on the wear characterization. It was difficult to compare the results obtained by different laboratories. Therefore, it is desirable to develop an artificial lubricant whose composition can be always set to a specified value as an alternative to bovine serum. In the present study, the effect of each major constituent in bovine serum on wear property was studied by hip simulator. As a result, transparent and stable lubricant solutions were prepared. It showed quite similar wear property to bovine serum by controlling the composition. These results serve as a guide to propose the new lubricant suitable for the wear characterization of hip joint.