Spinal Fracture: Cement No Better Than Sham

Aug. 5, 2009 -- A popular treatment for painful spinal compression fractures works no better than sham therapy in patients with osteoporosis, according to two new studies published today in the New England Journal of Medicine.

Researchers compared outcomes among patients who received injections of medical-grade cement to stabilize collapsed vertebra with those of patients who received a sham treatment.
Both treatments seemed to work, but patients injected with the cement showed no more improvement in pain and function than patients who received the sham treatment.

Cement injection, known medically as vertebroplasty, has become a leading treatment for osteoporosis-related spinal fractures. By one estimate, the number of vertebroplasties performed in the United States doubled between 2001 and 2007.

Same Outcome, Different Interpretations

The new studies are the most rigorously designed trials ever to examine the effectiveness of the cement treatment for the treatment of spinal compression fractures.

The two lead researchers differed in their interpretation of the implications for clinical practice.
“Our trial found no benefit for this treatment, so it should not be used in clinical practice,” says Rachelle Buchbinder, PhD, who led a team of researchers from Melbourne, Australia’s Monash University.

Interventional neuroradiologist David F. Kallmes, MD, of the Mayo Clinic, who led the second study, says more research is needed to determine if certain patients respond better to the cement injections than to other treatments.

“I think it’s fair to say that vertebroplasty does not work in the way that we thought it does, but it does work,” he tells WebMD. “It’s just that the (sham) treatment worked just as well and we can’t say why.”

The Australian study involved 78 patients with severe pain from osteoporosis-related vertebral fractures treated with either cement injections or a sham. Neither the patients nor the researchers knew which treatment was being given.

Both sets of patients received the same hospital care and local anesthetic before treatment. But those who did not get the cement treatment received cues such as pressure placed on the back and exposure to the smell of the bone cement.

The researchers measured pain, quality of life, and functional status one week after treatment and one, three, and six months later. They found that both groups had similar improvements in pain, function, and quality of life over time.

In the similarly designed Mayo Clinic trial, 131 patients from eight treatment centers in the U.S., U.K., and Australia were treated with either cement injection or sham.

One month later, both groups saw significant and similar improvements in pain, quality of life, and functional status.

Patients in the Mayo trial were able to “cross over” and get the other treatment after a month.
Even though they had no confirmation of which treatment that was, nearly four times as many patients who had the sham treatment switched, suggesting that more of them were less satisfied with their initial treatment.

“It is possible that there was a treatment effect (with the cement treatment) that we were just unable to measure,” Kallmes says. “I don’t think we should give up on this procedure. I think it needs to be studied in more detail.”

More Patients Needed for Trials

For this reason, Kallmes says he will not recommend the cement injections to patients in the future unless they agree to participate in clinical trials.

Interventional radiologist Avery Evans, MD, tells WebMD that there has been so much hype about the cement injections, patients have been reluctant to enroll in trials if it meant they might not get the treatment.

An associate professor of radiology and neurosurgery at the University of Virginia, Evans agrees that more research is needed to determine if vertebroplasty benefits specific subgroups of patients.

“Up until now no one was willing to randomize their patients because they were so convinced that vertebroplasty was the greatest thing in the world,” he says. “Now it’s time for us to admit that we aren’t as smart as we thought we were and ask the questions, ‘Are there patients who are helped by this treatment, and who are they?'"

In an editorial published with the studies, James N. Weinstein, DO, who directs the Dartmouth Institute for Health Policy and Clinical Practice, questioned whether the sham treatment really was a placebo treatment and whether either treatment was better than no treatment at all.

He pointed out that of the approximately 750,000 people who suffer from vertebral fractures each year, only about a third receive any kind of treatment.

“Although (the two trials) provide the best available scientific evidence for an informed choice, it remains to be seen whether there will be a paradigm shift in the treatment of vertebral compression fractures with vertebroplasty or similar procedures,” he writes.