Spinal Cord Stimulation
This is a interventional pain treatment option where pain is reduced by an implanted spinal cord stimulator (SCS). A SCS is a device consisting of electrical wires (leads) attached to a pacemaker like battery (generator). While considered less invasive than open spine surgery this treatment option is a bit more invasive than other interventional pain treatments as the device is implanted surgically with the leads implanted in the spine (epidural space) and the generator implanted under the skin, usually near buttocks or abdomen. SCS disrupts the pain signals traveling between the spinal cord and the brain.
What is being stimulated?
The SCS uses current to stimulate nerves based on where the pain is. Different nerve innervate different parts of you body. Where the pain is felt will help determine at what level of the spine to place the leads. The generator will deliver electric pulses to the leads placed over the spinal cord. These pulses will stimulate and modify pain signals before they reach the brain. The result can be that pain is either not perceived or replaced by a tingling feeling.
X-ray image of lead placement
What it does
The SCS transmits electric pulses created by the generator to the spinal cord via the leads and electric pulses will modify the pain signal. The response will depend on the frequency of the electric pulses. For example with SCS devices that generate a low frequency current the pain sensation will be replaced by a mild tingling sensation. Other SCS devices can generate high frequency current that can mask the pain without a tingling sensation.
What it doesn’t do
The SCS does not heal or treat the source of the pain and therefore does not “fix the problem”. All it does is alter the way the brain perceives the pain signal. Therefore results can vary person to person as far as how much pain relief is achieved. The goal is for at least 50% reduction of pain and improvement of function.
Then why do it?
The SCS is an option primarily for patients who have unfortunately failed all other options, even surgery. In fact one of the most common indication for SCS trial and placement is for patients who have back pain that continues even after surgery (failed back surgery syndrome). Other indications include chronic neuropathic (nerve injury) pain, complex regional pain syndrome, etc. The SCS is a surgically implanted electronic device. Prior to getting the device implanted there will be a one week trial during which the leads are placed inside the spine but the generator remains outside the body. If the trial is successful (meets certain criteria for reducing pain) then the definitive device will be surgically implanted. If the trial is not successful (does not meet criteria) than the device is not implanted and the trial leads are removed.
What are the risks?
Overall considered safe when performed with fluoroscopic (xray) guidance by spine surgeons and doctors who specialize in pain management (an anesthesiologist or physiatrist) who have been trained to implant spinal cord stimulators. Risks are similar to other spine interventions and include infection, bleeding, allergic reaction, pain aggravation, nerve injury, and paralysis (rare). Additional risks with SCS include device migration and device failure. In device migration the leads move from their original location and the stimulator doesn’t block pain as effectively. This may require a follow-up surgery to put the electrodes back in the proper spot. Device damage may happen due to a fall or intense physical activity. If the device is significantly damaged it will need to be surgically replaced.
