Bone Electrical Conduction

A new five-point electrode method was used to measure the conduction properties of rabbit femur. The two outer electrodes introduced current into the bone while the three inner electrodes (1 cm apart) were used to measure potential drop. Measurements were conducted at 20-7,000 hz for voltages of 0.1-1.2 volts. At 20-1,000 hz, the current charged the outer electrode bone capacitance, thereby causing frequency-dependent results. The in vivo resistivity of the femur cortex and medullary cavity was 1.0 × 103 ohm-cm.