Multiscale computation on mechanical environment of chondrocytes / 医用生物力学

ABSTRACT

Objective To compare the mechanical environment of chondrocytes between superficial zone and deep zone by multiscale computation. Methods The chondrocyte biphasic model was set up and made the results of the articular cartilage (AC) biphasic model mapped to the corresponding borders of the chondrocyte model as the boundary condition. The chondrocyte model was computed to obtain the results of the mechanical environment of chondrocytes and analyzed. Results The results showed that the stress of chondrocytes at deep zone was half of that at superficial zone, but both were much smaller than those outside chondrocytes. The pericellular matrix (PCM) sustained the high stress outside chondrocytes and remarkably reduced the stress inside chondrocytes. Interstitial flow directions adjacent to two chondrocytes were totally the opposite.Conclusions The bearing property of AC reduced the stress near chondrocytes at deep zone prominently and protected the chondrocytes at deep zone and subchondral bone. PCM sustained the high stress outside chondrocytes to provide lower stress environment for chondrocytes living. The opposite interstitial flow direction of two chondrocytes supported the theory that synovia seepage from cartilage surface and nutrient pumped out from subchondral bone constitute the bidirectional nutrient supply in AC.