Imaging tests for back pain are overused

"Immediate imaging is only recommended when cancer or infection is suspected, or if severe or progressive neurological deficits are apparent," says Orly Avitzur, M.D., board-certified neurologist and medical adviser to ConsumerReportsHealth.org.

The study suggests that such tests are actually on the rise. In 2006, back-pain patients seen in an ER were three times more likely to get a CT scan or MRI than were those in 2002.

New guidelines from the American College of Physicians, published in the February 1^st issue of Annals of Internal Medicine say that there is "strong evidence that routine imaging for low back pain by using radiography or advanced imaging methods [such as MRI or CT scan] is not associated with a clinically meaningful effect on patient outcomes." Moreover, they report that unnecessary imaging can lead to additional tests and treatments that pose needless risks and expense. 

The average radiation exposure from lumbar radiography is 75 times higher than for chest radiography, according to the ACP. That's especially a concern for women because it exposes their ovaries to radiation.

But that's not the only problem. The tests just aren't that good at finding the causes of back pain. Even when they do show something abnormal, like a bulging disc, there's little evidence that the abnormalities that show up are the actual cause of the pain. And "knowledge of clinically irrelevant imaging findings might hinder recovery by causing patients to worry more, focus excessively on minor back symptoms, or avoid exercise or other recommended activities because of the fear that they could cause more structural damage," the ACP authors say.

Financial incentives might motivate some doctors to order unnecessary imaging tests, especially when the physician belongs to a practice that owns the imaging equipment. But patient demand probably plays a role, too. In fact, several studies have found that patients are more satisfied when they get imaging tests, even when they fair no better. And doctors pressed for time might find it easier to simply order the test than explain why it's not necessary.

Bottom Line. If you visit a doctor for low-back pain, don't demand an X-ray, MRI, or CT scan. If your doctor orders one,  "you should ask why and how it will affect your treatment and management," says Avitzur. "Be especially cautious if your doctor or group practice owns advanced imaging equipment and refers you to those facilities," she says. Staying active through exercise, or physical or chiropractic therapy should often be tried before tests or treatment. In fact, back pain usually clears up on its own within a month or so.

 —Kevin McCarthy, associate editor

Find out what treatments for lower back pain worked for Consumer Reports subscribers.

—Joel Keehn