When an ailment is as common as back pain (affecting 8 out of every 10 people at some point), you'd think humanity would have locked down all the causes and cures by now. And while injuries to muscles or joints are a common cause of back pain, the truth is that many people have a bad back without really knowing what's causing it or how to treat it.

In fact, sometimes just sitting for a long time can be the cause. Here's a clue if your back pain takes the form of a burning pain, tingling sensation, or numbness that runs from your buttocks down the back of your legs: You may be experiencing piriformis syndrome.

Your piriformis muscle helps keep your posture stable while you’re standing or walking. What causes piriformis syndrome? In most cases, an injury or overuse (from long-distance walking or running, for example) will lead your piriformis muscle to press against the sciatic nerve. It can also develop from sitting for long periods, climbing stairs, or a traumatic event like a fall. When piriformis syndrome develops, you may feel pain after sitting, standing, or lying down for longer than 15 minutes; it may feel literally like a pain in the butt. You may also have difficulty walking or getting up, particularly when you’ve been sitting cross-legged on the floor with your kids. You may even experience headaches and neck pain as a result of piriformis syndrome.

There’s no one test for piriformis syndrome, but your doctor can do a number of tests to rule out other causes of your pain, as the syndrome shares symptoms with some other conditions. Your doctor should do a complete physical assessment as well as a neurologic history. Make sure you tell your doctor about any recent activities or injuries, as well as if you’ve noticed any other symptoms besides the pain.

If your doctor does diagnose you with piriformis syndrome, the good news is that there are a lot of noninvasive and inexpensive treatment options you can try. Your doctor may suggest using cold or hot packs, taking walking breaks during long periods of sitting, and massaging the area that's hurting. If you have a severe case of piriformis syndrome that doesn’t get better with these treatments, you may need steroid injections or surgery, but research shows that nearly 80 percent of patients feel better after non-invasive treatment options.

You can also talk to your doctor about stretching exercises, using a foam roller, exercise ball, or just your body, to stretch your hip flexors, quadriceps, and IT band. Here's one stretch you can try from the National Academy of Sports Medicine: Lie on your back. Keep one leg extended on the floor, and lift the other leg with your hip and knee bent 90 degrees. Hold the back of your bent leg and extend it into the air until you feel a stretch. Hold that for 30 seconds. Repeat on other side. (Floor bridges and ball squats are also good exercises to try.)

Want to take steps to prevent piriformis syndrome? Keep your body strong with regular exercise and maintain good posture no matter what you’re doing (i.e., both sitting and standing). Try to avoid sitting down for long periods (remember those walking breaks!). And when you're lifting your kids —or all their heavy stuff off the floor—bend your legs instead of bending at the waist, and be careful not to twist your body. Before you know it, you’ll have given your pain in the butt a kick in the butt.

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