Modulation of osteogenesis in fetal bone rudiments by mechanical stress in vitro.

Studies of organ cultures of developing bone subjected to intermittent mechanical stress are reviewed. Mineral metabolism in these bones is modulated by exposure to dynamic stress of physiological magnitude. Finite element stress analysis of long bone rudiments shows that hydrostatic pressure during organ culture produces significant shear stresses at mineralized/non-mineralized tissue interfaces, in addition to dilatational stress. Both matrix producing cells (chondrocytes, osteoblasts) and matrix resorbing cells (osteoclasts) are affected by mechanical stress in vitro. The organ culture model offers certain opportunities for studying effects of mechanical stress on skeletal tissue at the cell and tissue level.