Microelectrode study of stress-generated potentials obtained from uniform and nonuniform compression of human bone.

By use of a previously developed microelectrode technique, the effect of nonuniform stresses on the stress-generated potentials (SGP) in bone were studied to a resolution of 5 micrometers. Comparison was made between uniformly and nonuniformly applied compression of human cortical bone. It was found that the radial electric fields for osteons in a specimen under uniform compression were equivalent, and such specimens possessed no macroscopic SGP; for nonuniform compression, the electric fields of osteons differed, and a macroscopic SGP was measured. The magnitude of the macroscopic SGP thus appears to be dependent upon local stress differences and, hence, on the SGP of local regions.