Pulsed Inductive Coupling Method. In the treatment of nonunion, coils are placed around the cast on the limb and, with radiographic guidance, are centered directly over the nonunion site. An asymmetric pulse signal is applied for 8 to 10 hours daily. Studies have shown significant difference in success rate in patients undergoing less than 3 hours of treatment day versus those undergoing treatment for a greater amount of time. The inductive coupling method heals a nonunion in about the same amount of time as direct current, and the rate of successful healing is also about the same for both techniques.

Capacitive Coupling Method. In this second noninvasive method of applying electricity to nonunion, capacitor plates or electrodes are placed on the surface of the skin on either side of the underlying nonunion. A time-varying electric field is applied to the electrodes, which induces a secondary time-varying electric field in the tissues, including bone, between the electrodes. This noninvasive treatment also takes approximately the same amount of time as the other electric treatments and has approximately the same degree of success.

Whereas all electrical and electromagnetic stimulation techniques have shown some promise of beneficence, none has proven superior to revision surgery with bone grafting techniques, which remains the gold standard of treatment for nonunion.