Low back pain: When are imaging tests needed?

By Tanise Edwards, M.D.

For many people, low back pain is a sore subject. It occurs quite commonly — nearly everyone develops it at some point in life.

In fact, you may have back pain right now. And, maybe, you're wondering whether an imaging test — such as an MRI or X-ray — could uncover what's causing your pain.

But, before you ask your health care provider about testing, there's some important information you should know:

Your symptoms will likely improve with time. Low back pain usually goes away without treatment. Typically, that's in a matter of days. And, until then, over-the-counter pain relievers may ease discomfort. (See the sidebar for signs of back pain that could be serious.)

It's usually best to stay active. You might be tempted to lie in bed. But, studies have found that too much time lying down can actually slow recovery.

Imaging tests aren't without some risk. Health care providers must weigh the need for testing with the potential downsides. For one, test results may not always pinpoint the source of pain. And, sometimes they may be misleading. This can result in treatments that aren't needed. But, there are other issues to consider. Some tests — such as X-rays and CT scans — use radiation. The levels are considered safe. But, it's still best to avoid unnecessary exposure. And, of course, there's the out-of-pocket cost you may have to cover.

When pain lingers
The best way to get to the bottom of back pain that won't go away — or interferes with daily activities — is to work closely with your health care provider. He or she may do a physical exam and go over your symptoms. This is often how back problems are diagnosed.

Your health care provider may decide that an imaging test would be beneficial if your pain persists. Or, he or she may order one if a serious cause is suspected, such as nerve damage, infection or a tumor, for example. Common imaging tests used to diagnose back pain include:

• X-rays. Standard X-rays primarily show bones. They're often used to look for broken or injured vertebrae and spine deformities.
• Magnetic resonance imaging (MRI). MRI scans soft tissue and bones. These images can help reveal if back pain is triggered by a serious condition, such as disk disease.
• Computed tomography (CT). This test creates three-dimensional images using X-rays. It focuses mainly on bones. But, it can also show soft tissue and help diagnose conditions such as a ruptured disk.

Your health care provider is the best resource when it comes to back woes. Together, you can develop a plan to ease your pain — and keep it from returning. For example, your doctor may advise that you lose excess weight, get more exercise and work on your posture.

Dr. Tanise Edwards is board-certified in emergency medicine. She is a medical consultant for OptumHealth, reviewing guidelines and consumer health publications. Before joining OptumHealth, she practiced emergency and urgent care medicine. She is the co-editor of Urgent Care Medicine (McGraw-Hill) and is on the editorial board of The Journal of Urgent Care Medicine.