Bone Cell Responses to Fluid Flow

The relationship between mechanical loading and bone formation has long been documented (1 ). However, the identity of the transductory mechanism, conveying loading signals to bone cells, remains elusive. Mechanical strain, interstitial fluid flow, and streaming potentials are all likely candidates but the separate investigation of these factors has proven difficult. Studies in our laboratory and others have shown fluid shear stress to be influential in bone modeling and remodeling (2 –4 ). The characteristics of the flow causing this bone formation and probable inhibition of resorption have been more difficult to determine.