The effects of load on articular cartilage are complex. Dynamic loading of
cartilage is associated with slight cell and tissue deformation as well as
cyclical fluctuations in the hydrostatic pressure of cartilage and in fluid
movement. Static loading results in expression of fluid from the tissue, c
oncentrating extracellular matrix macromolecules and consequently increasin
g the concentrations of cations, reducing extracellular pH and increasing e
xtracellular osmolarity. Each of these alterations is implicated in regulat
ing the synthetic response of chondrocytes to load. However, the mechanisms
by which these changes affect matrix turnover are poorly understood. In th
is review we consider how load may affect chondrocyte behaviour through its
influence on membrane transport processes and thus on the intracellular en
vironment.