When complex spinal surgery is undertaken, is there a way to monitor the health of the nervous system? The answer is yes. During complex and sensitive spinal surgery, a technician can generate small electrical signals on the skin that can be read from the brain when the patient is under general anesthesia. This is called spinal monitoring. It is sensitive and helpful during surgery to scrutinize the function of the nerves and spinal cord.
When screws are being inserted into the vertebra, these screws can be monitored by sending a small electrical signal through them. We do this to see if the nerve roots which are next to the screws are being “insulated” from the screws by the bone of the pedicle. If the screw is too close to the nerve, the bony insulation will not be adequate and the nerve will respond to a lower voltage which warns the surgeon to investigate the position of that particular screw.
The spinal cord itself is also monitored and especially for deformity surgery (scoliosis and kyphosis correction), this tool is quite valuable to note the health of the cord.