Treatment of nonunion with constant direct current.

Laboratory experiments show the following relationships between electricity and bone: (1) stressed bone exhibits electronegativity in areas of compression, (2) living, nonstressed bone exhibits electronegativity in areas of bone growth and healing, and (3) the application of low magnitude direct current to bone induces osteogenesis at the negative electrode or cathode. Based on the above principles, a clinical study was performed in which 10-20 microamperes of constant direct current was used in treating nonunion in 57 patients. The results suggest that specific electrical parameters are required for successful osteogenic stimulation in patients. When these electrical parameters are met, a successful healing rate of 70 per cent can be achieved in treating nonunion with direct current. As experience is gained with this new technique in the treatment of nonunion, the results should improve even further. Basic studies exploring the mechanism(s) whereby electricity induces osteogenesis are opening new vistas into our understanding of bone growth and repair. The extension of these basic studies has far-reaching clinical implications.