The pericellular matrix (PCM) is a narrow region of cartilaginous tissue that surrounds chondrocytes in articular cartilage. Previous modeling studies indicate that the mechanical properties of the PCM relative to those of the extracellular matrix (ECM) can significantly affect the stress-strain, fluid flow, and physicochemical environments of the chondrocyte, suggesting that the PCM plays a biomechanical role in articular cartilage. The goals of this study were to measure the mechanical properties of the PCM using micropipette aspiration coupled with a linear biphasic finite element model, and to determine the alterations in the mechanical properties of the PCM with osteoarthritis (OA). Using a recently developed isolation technique, chondrons (the chondrocyte and its PCM) were mechanically extracted from non-degenerate and osteoarthritic human cartilage. The transient mechanical behavior of the PCM was well-described by a biphasic model, suggesting that the viscoelastic response of the PCM is attributable to flow-dependent effects, similar to that of the ECM. With OA, the mean Young's modulus of the PCM was significantly decreased (38.7±16.2kPa vs. 23.5±12.9kPa, p<0.001), and the permeability was significantly elevated (4.19±3.78×10-17m 4/Ns vs. 10.2±9.38×10-17m4/Ns, p<0.001). The Poisson's ratio was similar for both non-degenerate and OA PCM (0.044±0.063 vs. 0.030±0.068, p>0.6). These findings suggest that the PCM may undergo degenerative processes with OA, similar to those occurring in the ECM. In combination with previous theoretical models of cell-matrix interactions in cartilage, our findings suggest that changes in the properties of the PCM with OA may have an important influence on the biomechanical environment of the chondrocyte.

Original languageEnglish
Pages (from-to)509-517
Number of pages9
JournalJournal of Biomechanics
Issue number3
StatePublished - Mar 2005


  • Articular cartilage
  • Biphasic
  • Cell mechanics
  • Chondron
  • Finite element model
  • Micropipette
  • Modulus
  • Osteoarthritis
  • Pericellular matrix
  • Permeability


Dive into the research topics of 'Osteoarthritic changes in the biphasic mechanical properties of the chondrocyte pericellular matrix in articular cartilage'. Together they form a unique fingerprint.

Cite this