Bonnie Merenstein, 73, said lidocaine injections she received in a study might have worked as well as steroid injections. LEXEY SWALL FOR THE NEW YORK TIMES
The New York Times
By PAM BELLUCK
JULY 2, 2014
A widely used method of treating a common cause of back and leg pain — steroid injections for spinal stenosis — may provide little benefit for many patients, according to a new study that experts said should make doctors and patients think twice about the treatment.
Hundreds of thousands of injections are given for stenosis each year in the United States, experts say, costing hundreds of millions of dollars.
But the study, the largest randomized trial evaluating the treatment, found that patients receiving a standard stenosis injection — which combine a steroid and a local anesthetic — had no less pain and virtually no greater function after six weeks than patients injected with anesthetic alone. The research, involving 400 patients at 16 sites, was published Wednesday in The New England Journal of Medicine.
“Certainly there are more injections than actually should happen,” said Dr. Gunnar Andersson, the chairman emeritus of orthopedic surgery at Rush University Medical Center in Chicago, who was not involved in the research. “It’s sort of become the thing you do. You see this abnormality on the M.R.I. and the patient complains, and immediately, you send the patient for an epidural injection.”
Some people can still benefit from injections, he said, but now physicians “will be more cautious” and patients should ask, “Should I really do this?’ ”
Mostly, steroid injections are safe, carrying small risks of infection, headaches and sleeplessness. But in April, the Food and Drug Administration warned that they may, in rare cases, cause blindness, stroke, paralysis or death, noting that injections have not been F.D.A.-approved for back pain and their effectiveness has “not been established.”
Often caused by wear and tear, spinal stenosis occurs when spaces within the spine narrow, putting pressure on nerves and causing pain or numbness in the back and the legs. More than a third of people over 60 have some narrowing, research suggests.
Steroid injections, which reduce inflammation, are often tried when physical therapy or anti-inflammatory medication fails, with the aim of avoiding expensive surgery. Some insurance companies require injections before approving surgery.
The study provides evidence to tell some patients, “This probably isn’t going to work very well for you,” said Dr. Ray Baker, a past president of the North American Spine Society and the International Spine Intervention Society, who was not involved in the study. And because some participants received two injections without greater benefit, “it strongly speaks against the practice of performing multiple injections.”
But the study leaves the options for some patients unclear.
“We don’t have a lot of good things in our toolbox for spinal stenosis,” Dr. Baker said. “We’re really stuck with a problem” with an aging population.
Spinal injections are considered effective for other conditions, like herniated discs. But of the 2.2 million given annually to people on Medicare, about a quarter are for spinal stenosis, said Dr. Janna Friedly, a professor of rehabilitation medicine at the University of Washington and the study’s lead author. She said injections cost $500 to $2,000 each. The study helps answer questions raised by the Spine Society and the Cochrane Collaboration, a group of medical experts. Both issued reviews last year finding insufficient evidence to recommend injections for some types of stenosis.
“If the benefit really isn’t there and you do the procedure more and more, then all you’re doing is compounding the risk,” said Dr. Christopher Standaert, a co-author of the study and a professor at the University of Washington.
Dr. Scott Kreiner, a co-chairman of the Spine Society’s evidence-based guidelines committee, said the new research should “influence future guidelines.”
A rehabilitation medicine specialist in Phoenix who was not involved in the study, Dr. Kreiner says he will give fewer second injections and may refer some patients to surgery sooner. “This is probably a step toward eliminating or minimizing the use of epidural steroid injections for this problem,” he said.
Still, the research, funded by the federal Agency for Healthcare Research and Quality, leaves questions unanswered.
Because every patient received injections, and both groups reported similar improvement six weeks later, researchers cannot tell if patients would do as well without any injections at all. Also unclear is whether the anesthetic, lidocaine, did anything helpful when injected alone. Some experts said the benefits patients reported seemed larger than typical placebo effects.
“To me it’s unlikely that the lidocaine has a long-term effect,” Dr. Friedly said, “but there are people who think that it could.”
The study also did not represent all types of stenosis, involving patients with central stenosis, not stenosis on one side, which Dr. Andersson said was more localized and therefore possibly more treatable by injection.
Stenosis, Dr. Standaert said, “can be caused by all sorts of things.”
While some of his patients have done well with steroids, he said, “if the pain isn’t primarily due to inflammation, then maybe it’s not going to help.”
Still, two patients recently tried lidocaine-only injections and “didn’t get better,” he said. Some results suggest the issue is complex. Three weeks after injection, patients receiving steroids reported slightly greater function and less pain than the lidocaine-only group. By six weeks, the difference evaporated. When results were adjusted for how long patients had had stenosis, the steroid group had only tiny advantages in function.
The steroid group had slightly less depression and more satisfaction with treatment, possibly because of steroids’ mood-lifting effect, experts said. But those patients had more negative effects, like headaches, fever, infection and lower levels of the protective stress hormone cortisol.
Afterward, patients and their doctors were told which injection they received, and then offered another injection, the same or different. William Johnson, 58, of Plano, Tex., a former Air Force and postal employee now attending college, initially received the steroid. He said his pain “immediately went away,” he did not need another injection and, 18 months later, remained pain-free.
His doctor, Dr. Thiru Annaswamy of the Dallas Veterans Medical Center, said by email: “There are patients who clearly respond to steroid injection. However, it is unclear why some do, and others don’t.” And Mr. Johnson “may have responded to the lidocaine-only injection, too.”
Another participant, Bonnie Merenstein, 73, a retired teacher in Denver, received lidocaine-only injections and requested another. Years ago, she said, steroid injections provided minimal improvement, and before the study, “I really could not walk for more than eight minutes without my legs going numb.”
Afterward, numbness lessened, grocery shopping and museum-going became easier, and she recently biked and canoed with her granddaughter.
“I believe that the lidocaine may have been as effective as a steroid,” she said.