Field distributions in the rat tibia with and without a porous implant during electrical stimulation: a parameteric modeling

A finite-element method was used to calculate the electric field gradients and current densities present in a rat tibia modeled with a porous intermediary implant when capacitively stimulated. Results indicated that while the current density in the pores is reduced in comparison to the region just outside the pore by about one order of magnitude, a significant current density still exists in the pore region. Furthermore, the presence of the implant increases the current densities in the trabecular bone while decreasing these values in the cortical bone. Replacing the trabecular bone in the pore by saline increases the current density in the pore by three-fold, but decreases the voltage gradient by a similar factor.