Intraosseous pressure and strain generated potential of cylindrical bone samples in the drained uniaxial condition for various loading rates.

Cortical bone is a composite material consisting of a porous elastic solid and viscous fluid. It is well known that the intraosseous fluid circulates as a result of a bone fluid pressure gradient in the porous space of the cortical bone. When a time-dependent mechanical load is applied to the bone, intraosseous fluid flow occurs through the interconnected pore space in the bone. Bone fluid flow leads to a strain generated streaming potential (SGP). However, there is no experimental study on the relationship between the generation of intraosseous pressure and the SGP. The purpose of this study was to obtain the relationship between SGP and intraosseous pressure generations in cortical bone. In order to understand the issue, a drained, one-dimensional experimental setup for fluid-filled cortical bone samples with four different strain rates was used to simultaneously measure the intraosseous pressure and SGP. The results revealed a significant correlation (r = 0.98, p = 0.02) between the generation of the SGP and the intraosseous pressure, which indicates that an intraosseous pressure gradient produces a SGP in cortical bone.