electrically stimulated osteogenesis /ilek″triklē/ [Gk, elektron, amber; L, stimulare, to incite; Gk, osteon, bone, genein, to produce] , a bone regeneration process induced by surgically implanted electrodes conveying electric current, especially at nonunion fracture sites. The process is effective because of the different electric potentials within bone tissue. Viable nonstressed bone is electronegative in the metaphyseal regions and over a fracture callus and electropositive in the diaphyses and other less active regions. Electric stimulation of fractures can accelerate osteogenesis, forming bone more quickly in the area of a surgically inserted negative electrode. The precise mechanisms by which electricity induces osteogenesis are not understood, but research shows that when cathodes are implanted at a fracture site and an electric potential of less than 1 volt is applied, oxygen is consumed at the cathode, and hydroxyl ions are produced, decreasing the oxygen tension of the local tissue and increasing the alkalinity. Low tissue oxygen tension encourages bone formation, which follows a predominantly anaerobic metabolic pathway.
