Piezoelectricity in Bone

Piezoelectricity (from the Greek piezo or piezein, to squeeze or press) refers to the ability of certain materials to generate electrical potentials in response to mechanical stress. This phenomenon may be familiar to musicians as the basis of piezoelectric pickups in acoustic-electric instruments.

Crystals such as quartz, as well as biologic tissue such as bone have been shown to generate electrical potentials in response to mechanical stress. For example, recordings from the human tibia during walking have shown generated electric potentials as high as 300 mV. These electrical potentials have been shown to be generated by shear forces of collagen and deformation of fluid-filled Haversian and Volkmann channels.

Because electromagnetic fields have been shown to affect cell division rates, tissue growth, and wound repair, alterations in bone architecture due to mechanical loading are thought to be mediated by piezoelectricity. Tissues, such as bone, that can generate endogenous electrical signals show a higher capacity to regenerate. This phenomenon is thought to be mediated at the level of receptors at the cell membrane.

References

• Isaacson BM, Bloebaum RD. Bone bioelectricity: what have we learned in the past 160 years? J Biomed Mater Res A. 2010 Dec 15;95(4):1270-9.