Abstract:
This study explores the biomechanics of cartilage at the cellular level, specifically addressing the mechanical interactions among chondrocytes using computational biphasic finite element modeling. Traditionally, cartilage mechanics simulations have used simplified single-cell models embedded in an extracellular matrix (ECM), neglecting potential interactions between cells. To investigate the significance of these interactions, the authors compared a single-cell model with an anatomically realistic eleven-cell model representative of physiological cellular distributions found within human cartilage. Simulations involved applying confined compressive strain to evaluate stress relaxation, cell deformation, and fluid mechanics in the extracellular and pericellular matrices.
The findings reveal significant mechanical differences during transient loading phases, with up to 60% variations in biomechanical metrics observed between single-cell and anatomically realistic multi-cell scenarios. These variations underscore the importance of intercellular interactions and cell location, especially in regions of high cellular density. Although steady-state responses between single and multi-cell models were relatively similar, the transient biomechanical response demonstrated critical implications for understanding cell mechanobiology, cartilage health, and potential degeneration pathways. This study advances biomechanical modeling methodologies by highlighting the necessity for anatomically accurate cellular arrangements to better predict and interpret cartilage mechanical responses in health and disease states.
