People with chronic, intractable back pain know exactly what they need ? relief directly where it hurts. Peripheral nerve field stimulation (PNFS), the newest weapon against back pain for people who are finding no relief from conventional treatment, does just that, says Dr. Eugene Lipov, who is Director of Research, Alexian Brothers Hospital Network Pain Program.
Electrical leads are placed just under the skin at the source of the pain, and the area is stimulated by a feed of electricity from an implanted power pack. Patients feel their pain replaced by a slight tingle.
This is an exciting evolution of the dorsal column stimulator for the spine, which has been in clinical use for the last 20 years. Where the previous stimulator was placed in the spinal canal right behind the spinal chord, this is placed at the site of pain, making it very effective for lower back pain and rendering it essentially free of complications.
?PNFS is becoming increasingly recognized as a minimally invasive, safe and easily reversible treatment for a range of chronic conditions, especially low back pain, a common cause of disability and one that is typically difficult to treat effectively,? Dr. Lipov notes.
After PNFS, most back pain sufferers are able to immediately decrease or stop pain medication. This is important because non-steroidal anti-inflammatories (NSAIDs) such as Naproxen, ibuprofen, aspirin and others are responsible for 7,600 deaths each year and 76,000 hospitalizations for gastrointestinal bleeds. Back pain sufferers often take NSAIDs routinely, as they are generally perceived as safe and are readily available
Technology takes a step forward
Ken Jahnke knows chronic back pain. Jahnke, 69, has undergone several spinal injections and six surgeries to relieve his pain, including a laminectomy, a fusion of areas of his upper and lower back, and an epidurolysis ? a procedure to remove scar tissue in the epidural space of the spine so medication can reach the affected nerves. The procedures resulted in only a limited reduction of pain. In fact, Jahnke?s pain was so intense and debilitating, he wasn?t able to walk more than a quarter block in 20 years. Believing Jahnke to be an ideal candidate for PNFS, Dr. Lipov suggested he undergo the procedure.
First Dr. Lipov implanted the leads, directly where Jahnke indicated he was having the most pain. Since this stage of the procedure is minimally invasive, patients are awake and able to tell the physician where the pain is coming from. An external power source is used until it?s determined that the stimulator will help the patient. Jahnke went home and tried it for a week. He reported significant relief, and a week later, an internal power source was implanted. The battery power lasts five-seven years and the longest stimulator implanted to date has been in place 20 years.
While earlier attempts of nerve stimulation to block pain worked directly on the nerves affected, PNFS works in the area of pain, peripherally or in the region affected, acting like a gate to stop the pain signal to the nerves and thus to the brain. In effect, PNFS is like a pacemaker that retunes the spinal chord to stop the pain.
Three days after the PNFS procedure, Jahnke reported an 80 percent reduction in pain. ?I got my father back and we want to tell the world,? his daughter said.
?There is minimal risk with PNFS, and the fact that we know before we implant the internal power source whether it?s going to work makes the procedure that much more impressive,? Dr. Lipov says.
PNFS is an ideal pain solution for patients who have had back surgery that has failed, people too old or sick for surgery, or for those whose cause of pain cannot be diagnosed and yet suffer in pain day after day. The device is not intended for minor back pain or as a first course of therapy, Dr. Lipov says. In addition, it can help patients suffering from shingles, pancreatitis, and graft site pain.
A Duke University study in 2004 found that patients suffering from back pain consume more than $90 billion annually in health care expenses, with $26 billion of that going directly toward treatment. This does not begin to even take into account loss of work, depression suffered by people in chronic pain, and an overall diminished quality of life.
For many of those people, PNFS is the chance for long-term relief, directly where it hurts.