Spinal Cord Stimulation
By William L. Lippert, M.D., Colorado Springs LIVING WELL Magazine
In a previous issue of Colorado Springs LIVING WELL Magazine, we addressed an overview of spinal pain management. We covered preventative care, causes of spine and associated limb pain, diagnostic testing, and conservative treatment possibilities.
But what about the patients who have failed to achieve good pain relief despite everyone’s best efforts? Uncontrolled pain in this population can result in ongoing suffering, depression, loss of income and employment, and significant impact on quality of life. One of the more powerful tools at our disposal, and the topic of this article, is a sophisticated treatment called spinal cord stimulation (SCS).
SCS is a minimally invasive reversible therapy used to reduce the number of pain signals that reach the brain. This therapy involves placing leads inside the spinal canal (the same space where epidural catheters for women in labor are placed, as well as epidural steroid injections) that create a soft electrical sensation that “stimulates” the spinal cord in the exact area of the patient’s pain. While the exact mechanism to explain SCS is unknown, it may be based on a landmark theory called the Gate Control Theory of Pain, published in 1965 by Melzack and Wall. This theory suggests that stimulation of larger sensory fibers (particularly touch) will decrease pain signals. Many of us have put this theory to the test when we have skinned a knee on the sidewalk and we immediately squeeze or rub our leg; this actually decreases the pain we feel! The first SCS was placed by Shealy in 1967 and over the next 40 years the technology has dramatically evolved.
Who is a candidate for SCS? Any patient who has failed more conservative therapies, who suffers from uncontrolled neuropathic (nerve or nerve system damage) pain may be a candidate for SCS. This involves a varied patient population with radiating pain in the arms and legs (sciatica), residual pain after spinal surgery, pain from injured discs, complex regional pain syndrome (RSD), post-herpetic neuralgia, peripheral nerve injuries, cervicogenic headaches, and peripheral neuropathy. Other less common indications may include leg pain from peripheral vascular disease, uncontrolled angina, and abdominal pain (i.e., pancreatitis).
Once a patient is considered a good candidate for placement of a SCS, he or she will first undergo placement of a trial stimulator. Most trial leads are placed through a needle and require no incisions. With the patient under mild sedation, only local anesthesia is necessary. The patient reports to the physician where the tingling/massaging sensation is felt. The lead is manipulated until the patient reports good coverage of the pain area and the lead is secured in place. A typical trial lead placement would take roughly an hour or less to complete. The trial period typically lasts a few days to a week and is devoted to testing the efficacy of stimulation and determining how well the SCS relieves the patient’s pain in normal day-to-day activities. The beauty of the trial is you can “drive it before you buy it.” If the trial is not to the patient’s liking, no tissue destruction has occurred and all options remain open.
If, based on the trial, the patient feels the SCS would improve the quality of life, then he or she would be scheduled for permanent implantation. Implantation involves permanent placement of a SCS system. This system consists of stimulator leads and a power source, called a pulse generator. The implantation will be done by a spine surgeon if a special surgical lead is to be placed, or by the pain specialist if percutaneous leads are utilized. The entire system is placed under the skin during a brief outpatient procedure. After a few weeks of healing, normal activity can be resumed with few restrictions.
The positive attributes for SCS remain very attractive. No restriction in activities is necessary with SCS and in fact many patients enjoy increased function with decreased pain. Less medications are needed resulting in less drug side effects such as loss of balance, confusion, sleepiness, and constipation. The patient remains in control of his or her pain by adjusting the levels of stimulation whenever necessary. In looking at a variety of studies of effectiveness two years after implant, 60-70% of implanted patients continue to enjoy good pain relief.
The effect of inadequate treatment of pain has a devastating influence on life. When contemplating the next operation for improving your quality of life, talk to your physician and consider the alternative of spinal cord stimulation.
William L. Lippert, M.D., is board certified in pain management and anesthesiology. He may be reached at 719-380-7246.
