Spinal Cord ‘Pacemaker’ Reduces Chronic Back Pain

An estimated 100 million Americans are affected by chronic back pain and the side effects, which include difficulty walking, sitting, basic household chores, light activities, and getting in and out of a car.

Fortunately, there is a device that helps the back override pain. Doctors sometimes refer to this device as a “pacemaker for the spine.”  Although it does not pertain to the heart, it can manipulate nerve pathways, significantly reducing chronic back pain for patients who have exhausted all other therapies, or options that include surgery.

It’s formally called a Spinal Cord Stimulator, and it can be a last resort for patients suffering from back pain that disrupts daily functioning, just as a pacemaker can regulate heart muscle contractions and provide the mechanism for a relatively normal life.  Both devices are implanted under the skin.

In the case of the Spinal Cord Stimulator (SCS), the nerves in the spinal cord can be modulated with a devise, and different programs can be used via a remote control device by the patient at any time.

“When you put the electrodes over the nerve, you send some electrical impulses that activate the nerve in a different manner, overriding painful stimulating,” said Julian Naranjo, M.D., an interventional pain specialist, who recently implanted the first MRI-compatible Spinal Cord Stimulator in a patient at West Kendall Baptist Hospital.  “With the device, you can switch one sensation over another. We change or distract the nerve.”

Instead of pain, sometimes patients feel a tingling sensation in areas where they previously experienced pain.  The success rate of this advanced neurostimulation therapy can be significant, with patients averaging 50 percent to 90 percent pain relief, said Dr. Naranjo.

MRI-Compatible Device
About two months ago, Dr. Naranjo implanted a Spinal Cord Stimulator that is MRI-compatible, meaning the patient can undergo magnetic-resonance imaging procedures safely. The device was approved by the U.S. Food and Drug Administration just a year ago, and launched in the U.S. in August  2013 for body MRI scans under specific conditions of use.

Patients with this new Spinal Cord Stimulator implant can now undergo MRIs for any other health concern that could arise, without worrying that the machine will disrupt the stimulator’s functionality, said Dr. Naranjo.

The Spinal Cord Stimulator usually is an option for back patients whose pain is not isolated to a severe or specific disk herniation or injury. More likely, the best candidate for the implant suffers from more generalized and persistent pain that can come with age and degenerative conditions, such as failed back surgery syndrome, spinal stenosis (the narrowing of the spinal canal), arthritis and “degenerative disc disease”.

Procedure is Done in Two Phases: 1) Trial 2) Implantation
The patient who was provided with the first MRI-compatible Spinal Cord Stimulator is a 70-year woman who could not undergo back surgery because of her severe asthma and other medical conditions.

As it is done with in all SCS- implant cases, Dr. Naranjo said that he had this 70-year-old patient go through a trial phase, in which a lead is implanted temporarily in the spinal canal and is connected to a trial spinal cord stimulator.  The trial stimulator is programmed with one or more programs, customized to the specific areas of the patient’s pain. The trial helped Dr. Naranjo determine if the patient was responding to the therapy. The parameters used included pain relief level of greater than 50 percent, increased functionality, decreased need for medications, and improved mood and sleep pattern.

Following the successful trial,  the 70-year-old patient underwent the hour-long implantation procedure under local anesthesia —  avoiding general anesthesia is another advantage of the procedure — to implant the MRI-compatible Spinal Cord Stimulator. She was ambulatory later the same day, as are most implant patients.

“This patient had chronic lower back pain and surgery was a very high-risk option,” said Dr. Naranjo. “She had taken medications and injections and nothing had worked. But after the implant, she is reporting 80 to 90 percent pain reductions. She’s back to living a relatively normal life, walking and doing different tasks.”

Neurostimulation therapy that includes the lead trial and permanent implant can help reduce or even eliminate the use of pain medications. Overall, this implant therapy may include:

“Technology is getting amazingly better and the MRI-compatible device is the latest breakthrough, but neurostimulation with implants has been around for years,” said Dr. Naranjo.  “The general public doesn’t know too much about it. That’s unfortunate, because the success rate for pain reduction is significant for those who are candidates for the implants.”

Tags: diagnostic procedures, health & technology, Spinal Cord Stimulator