Bone grafts are used in spinal fusion surgery. The graft material grows into the surrounding bone, essentially “healing” two or more vertebrae together. The faster the graft grows, the better. Problems usually arise if the bones do not heal together, so doctors have tried different ways to improve the rate of healing. Over the past 25 years, surgeons have used electrical currents to promote faster growth of the bone graft.
Electrical stimulation in spinal fusion is an evolving technology. There are several ways to apply electrical stimulation. The different methods are based on different theories of why and how electrical stimulation works. The main three methods of electrical stimulation are direct current, pulsed electromagnetic fields, and capacitative coupling.
It is not always clear which type of stimulation will work best. The technology is still too new, and not all spinal fusion surgeries are alike. Spinal fusion is done for a number of different spine problems. There are also several different surgical techniques that can be used.
These authors sorted through the existing research on electrical stimulation. Their review suggests that electrical stimulation can improve the success rate of spinal fusion. They found that direct current seemed to work better than the pulsed electromagnetic fields. Capacitative coupling is too new to know for sure, but it also seems to be more promising than pulsed fields. The authors expect increased use of electrical stimulation in future spinal fusion surgeries.