External bone growth stimulation for spine fusion

• Small, wafer-thin skin pads/electrodes that are placed directly over the fusion site and deliver Capacitive Coupling (CC) stimulation, or;
  
  
• One or two treatment coil(s) delivering electromagnetic fields via Pulsed ElectroMagnetic Fields (PEMF’s), or Combined Magnetic Fields (CMF), placed into a brace or directly onto the skin.

One or two coils that generate an electromagnetic field at the fusion site are generally worn three to eight hours per day for three to six months after a spinal fusion.

The main drawback for this type of device is that the degree of patient compliance with the recommended treatment can hinder the clinical efficacy. If the patient does not wear the device they will not receive the benefits from treatment.

The mechanism of action of external bone growth stimulation is not completely understood. There are published scientific papers that have demonstrated different biological responses. However, these responses have not been demonstrated in the clinical setting. Studies indicate that there is an increase in the vascular supply to the region, which leads to enhanced calcification of the bone fusion.^{10,11,12,13,14}

For information on new external bone growth stimulators, see also New devices.