Electric current has been used to increase bone growth after fractures for almost 50 years. It’s use after spinal fusion is relatively new. There are several ways to deliver the electric stimulation to the bone. The doctor may implant a device right in the spine at the time of the fusion.
There are external units, too. One device is worn with a brace eight to 10 hours/day for six to eight months. The patient must put the brace on for the electric current to reach the spine.
Another external device uses a small computer-controlled stimulator. The electric current goes through flexible cables to patches placed on either side of the spine. The stimulator is worn 24 hours/day until healing takes place.
There are good points and problems with each type. Implanted devices have batteries that can leak or stop working. Another operation is needed to make repairs. This type doesn’t require patient cooperation to work.
The external units don’t cause infection or a second surgery to make repairs. However, this type only works if the patient wears it every day for many hours. More studies are needed to compare each type before we’ll know which is best for spinal fusion.