BOSTON - If you are one of the estimated 1.5 million Americans who will be diagnosed this year with a contained herniated disc - also known as a 'thrown-out back' or 'pinched nerve' of the upper leg - the answer may be as familiar as your radio. Doctors at Beth Israel Deaconess Medical Center are using radio waves - the same energy that sends signals to your car radio - to gently dissolve small amounts of unwanted disc tissue and relieve the pressure often associated with lower back and upper leg pain.
For patients whose body motion is restricted by a spine disc attack and who can't stand the prospect of a sometimes lengthy and painful convalescence, radio wave injection may be just the answer, says Joshua A. Hirsch, M.D., an interventional neuroradiologist and associate professor of radiology at Harvard Medical School. Virtually bloodless and exceptionally precise, Nucleoplasty radio wave injection is more like getting a vaccination or epidural steroid injection than traditional open-spine surgery.
"Nucleoplasty fills a serious technology gap that has existed for millions of spine disc sufferers," says Hirsch. "Since approximately 80 percent of back and leg pain sufferers are not appropriate candidates for disc surgery, the focus until now has been on trying to manage the problem with drugs, epidural injections and physical therapy. Nucleoplasty radio waves provide patients with the possibility of a permanent solution that drugs and therapy can't provide, but without the stress of traditional open-spine techniques."
Nucleoplasty radio wave injection is an offshoot of a technology used to treat over one million patients since 1995 for a variety of common medical problems, ranging from knee injuries to sleep apnea. A version of the technology for decompressing spine discs was approved for physicians' use by the FDA last summer.
Hirsch is the first doctor in New England to offer radio wave injection for treating disc problems associated with lower back and upper leg pain. He says his success rate so far is comparable to that of major surgeries but without the trauma, recovery time and cost.
Nucleoplasty (literally, removing part of the disc's nucleus) usually takes about 30 minutes and is typically performed while the patient is awake and under a local anesthetic and light sedation. Most patients walk out of the clinic in about an hour and are back at work in two to three days, Hirsch says. The only cutting required is for a one-millimeter opening (about the diameter of a lead of pencil) in the lower back where the injection device is inserted. In the past, most spine disc attacks were treated with weeks and possibly up to two months of bed rest, plus narcotics for pain, anti-inflammatory drugs and physical therapy for body motion, and a variety of alternative techniques ranging from acupuncture to massage.
In extreme cases, open-spine procedures may be required to remove some (microdiscectomy surgery) or most (fusion surgery) of the nucleus in problem discs. Nucleoplasty radio wave injection is intended for the vast middle of the market - people with mild-to-moderate cases who want quicker and potentially more permanent relief than drugs and bed rest can offer, but who are not severe enough for open-spine procedures.
Contained herniated disc begins when the soft, gel-like substance in the center, or nucleus of the disc comes into contact with a weakened area in the disc shell. If the shell is weak enough, the nucleus material can create an unnatural bulge in the shell. In other cases, the material seeps out of the shell. In both cases, the soft nucleus material that is supposed to function as a shock absorber for the spine actually becomes an irritant, creating pressure on the spine's sensitive nerve endings and bringing pain to the lower back and-or upper leg.
Radio wave injection is designed to gently dissolve the excess nucleus material that creates bulges in the disc and irritates nearby nerve endings in the spine.
Although radio waves have been used on a limited basis in medicine for years, recent technological advances have enabled radio wave devices to replace more conventional devices. Radio waves are considered a potentially optimal energy source for certain surgeries because these signals can be exceptionally precise and controllable in a doctor's hands, uniform in the way they heat and dissolve unwanted tissue, and, because they are cooler than some other energy sources, more gentle on the patient since damage to surrounding tissue is minimized.
"With Nucleoplasty radio wave technology, I believe we are on the threshold of a new generation of medical devices that will treat ordinary diseases with greater precision for the surgeon and greater gentleness for the patient," Hirsch says.
Beth Israel Deaconess Medical Center is a major patient care, research and teaching affiliate of Harvard Medical School and a founding member of CareGroup Healthcare System. Beth Israel Deaconess is the third largest recipient of National Institutes of Health research funding among independent U.S. teaching hospitals.