Stefan S, Sansen W, Mulier JC. Experimental study on the electrical impedance of bone and the effect of direct current on the healing of fractures. Clin Orthop Relat Res. 1976 Oct; (120):264-7.

An experimental study of the electrical impedance of cortical bone and medullary cavity and on the effect of a D.C. or a periodically interrupted D.C. on the healing of fractures in rabbits, suggests that the bone behaves as a capacitance of about 20 muF in parallel with a high D.C. resistance. Also a 10 muA periodically interrupted D.C. current stimulates osteogenesis.