Poster 2: Cell and Tissue Studies

Shamimur Akanda, David Burris, Christopher Price

University of Delaware

Articular cartilage, a triphasic tissue in our joint, maintains vanishingly low friction coefficient over decades. The presence of negatively charged proteoglycans and counter ions in the tissue causes Donnan osmotic swelling pressure influencing cartilage material properties. Although cartilage is compromised by its lubricity under habitual static loading, our recent discovery of ‘Tribological Rehydration’ fosters active fluid recovery into cartilage. However, how external bathing solution osmolarity influences cartilage tribological rehydration is yet to be identified. The objective of this study is to determine the influence of bathing solution osmolarity and composition on tribological rehydration and cartilage lubrication under the biofidelic sliding conditions of the cSCA configuration. For all approaches,19 mm diameter explants from femoral condyles were extracted. In the first two approaches approach, the effect of bath osmolarity and composition on tribological rehydration was assessed from the initiation of sliding (Both high and low fluid load support) and no significant effect of osmolarity was observed on cartilage lubrication. However, in the third approach, explants were stiffened or softened by bath osmolarity before sliding. Interestingly, it resulted in significantly compromised lubrication for the stiffer explants. This study concludes that stiffening the tissue through bath osmolarity compromises the lubricating ability of cartilage.

Research Area: Cartilage