Structure-function of cartilage in osteoarthritis: An ex-vivo correlation analysis between its structural, viscoelastic and frictional properties

Healthy articular cartilage is characterized by extremely low friction and high compressive stiffness. This dual-functionality is tailored by its biphasic structure, whereby a fluid phase interacts with the extracellular matrix. Osteoarthritis (OA) causes structural changes, thereby altering the biomechanical and frictional properties. How the structural and functional properties of human cartilage are associated with OA remain unknown. To address this, we identified relationships between structural parameters, viscoelastic and frictional properties of degenerated human cartilage through correlation analyses. We found that cartilage friction was mainly influenced by its microscopic structure, while the viscoelastic properties were also related to the macroscopic structure. The viscoelastic and frictional properties displayed a weak correlation. These findings provide insights into the interplay between cartilage structure and its functional properties in OA, which might provide a basis for advancements in diagnosing and treating degenerated human cartilage.