Hundreds of thousands of people with back pain have surgery every year. Some with a common condition called spinal stenosis have found relief after surgery, but there had been no clear evidence it was better than nonsurgical treatment options. Now, the latest finding from the Spine Patient Outcomes Research Trial (SPORT) shows that people suffering from spinal stenosis, a narrowing of the spinal canal, improve more with surgery than with nonsurgical treatments.

Back: Spinal stenosis is the most frequent reason for low-back surgery in patients over 65. But until SPORT—a seven- year, $21-million, Dartmouth- led study—no one knew for sure if it was the best choice because the options had never been tested in a large randomized trial. The same was true for two other common back conditions: herniated disk with sciatica and a variation of spinal stenosis, where one vertebra has slipped forward over the other, called spondylolisthesis. SPORT showed that surgery helped to varying degrees for those conditions, too (see the articles "Back-surgery papers show SPORT utility" and "Giving spines a SPORTing chance" for details).

"For the first time," says James Weinstein, D.O., SPORT's principal investigator, "we have an evidence base on which to advise our patients."

Data: In the stenosis study, 289 patients were randomly assigned to surgery or nonsurgery groups, and 365 could choose to have surgery or not. As the study went on, many randomized patients changed their minds; some assigned to have surgery decided against it, and vice versa. So the paper, published in the February 21 issue of the New England Journal

Surgery reduced pain and
improved physical function
much more.

of Medicine, contains a dizzying array of numbers.

But the bottom line, says coauthor Tor Tosteson, Sc.D., is in the "as-treated" figures. When the data was analyzed according to what treatment people actually got—surgery or nonsurgical therapy—they found that surgery reduced pain and improved physical function much more. On a 100-point scale, surgery patients' pain improved an average of 28 points (compared with 12 points for nonsurgery patients). And surgery patients' physical function improved an average of 25 points (compared to 10 points for nonsurgery patients).

Gain: Those treated nonsurgically—with physical therapy or painmedications, for example—improved, too, just not as much as those who had surgery. "Any gain over 10 points on this scale seems to be worth it," says Tosteson. For instance, 10 points can mean being able to lift a bag of groceries or not.

Weinstein and his coinvestigators have now launched a website using data from the stenosis trial to help patients (and doctors) estimate the benefits of surgery versus nonsurgery. There is still a lot of uncertainty, says Tosteson, because people's health histories can vary widely. But for those with spinal stenosis, the decision of whether to go under the knife now has a little less guesswork and a little more evidence behind it.