Evaluation of a superior lubrication mechanism with biphasic hydrogels for artificial cartilage

To extend the durability of artificial joints, biomimetic artificial hydrogel cartilage is proposed as a way of improving the lubrication mechanism in artificial joints. The application of hydrogels with properties similar to those of articular cartilage can be expected to duplicate the superior load-carrying capacity and lubricating ability of natural synovial joints. Frictional behaviors with three kinds of poly(vinyl alcohol) (PVA) hydrogels with high water content were examined in reciprocating tests. Interstitial fluid pressure, von Mises stress and fluid flow were compared in biphasic finite element analysis, and frictional behavior was evaluated in terms of biphasic lubrication and surface lubricity. Hybrid gel prepared by a combination of cast-drying and freeze-thawing methods showed superior low friction. •Hybrid gel as cast-drying/freeze-thawing gel showed superior low friction.•Frictional behaviors of PVA hydrogels could be estimated by biphasic FE analysis.•Friction of hydrogel was controlled by surface lubricity and fluid load support.•Hybrid gel has ability to be optimized for surface lubricity and fluid load support.