Think that hip pain is bursitis? Think again.

Pain on the side of your hip is more likely from tendinitis, tight muscles, or another condition.

 Image: © Jan-Otto/Getty Images

Hip bursitis — an inflammation between your thighbone and nearby tendons — is commonly diagnosed when patients have pain on the outer side of the hip. However, several other conditions can cause similar pain, and require different treatments. "Doctors often assume that pain on the outer side of the hip is due to bursitis. But 90% of the time, it's not bursitis," says Dr. Lauren Elson, a physiatrist with Harvard-affiliated Massachusetts General Hospital.

What's causing the pain?

Dr. Elson says pain in the side of your hip most often results from one of the following conditions:

Tendinitis. This is an inflammation of the tendons (fibrous bands of tissue) that connect the gluteal muscles in your buttocks to the hip bone. "Tendinitis develops because of muscle imbalance. It could be from a lack of activity, crossing your legs, or even sitting on a wallet," Dr. Elson says.

Overuse injury. When you walk or run, weak hip and buttock muscles can tighten and irritate the iliotibial (IT) band — a long band of connective tissue that runs from the knee to the hip. It merges with the gluteal muscles to stabilize the leg.

Tight muscles in the buttocks and hip. If the gluteal muscles and IT band are too tight, they pull at the thighbone where they attach, and that causes pain on the side.

Spine problems. "The body isn't always smart in recognizing where the pain is coming from," Dr. Elson explains, "and spine arthritis, a pinched nerve, or bones in the spine rubbing together can create pain in the side of your hip."

Symptoms and diagnosis

With all of these conditions, the pain lingers or even worsens when you lie on your side, or when you sit and cross your legs. It may ease with activity. But left untreated, the pain can become so severe that you're unable to walk.

You may need to seek treatment from a primary care physician or specialist (such as a physiatrist, sports medicine specialist, or physical therapist) who can interpret your symptoms and imaging tests to determine the cause of pain on the side of your hip.

Starting your treatment

The good news: "Pain almost always goes away with targeted exercise and stretching," says Dr. Elson.

She typically recommends massage and a course of physical therapy, which focuses at first on easing tight tissues by stretching them. These include the hip flexors, the IT band, and the piriformis muscles in the buttocks.

It's also important to avoid habits that can tighten muscles and add to pain at the side of the hip, such as crossing your legs or sitting too long.

Strengthening the muscles

Along with improving flexibility, physical therapy sessions aim to strengthen the abdominal or core muscles, such as the transversus abdominis muscle. "This helps align the pelvis better, so you won't stress the hip when you stand or walk. Stronger abdominals also support your spine," explains Madhuri Kale, a physical therapist at Harvard-affiliated Brigham and Women's Hospital.

With a stronger core, you can then move on to strengthening the muscles at the hip that let you move your leg in various directions. "We may have you do side or back leg lifts, performed while standing, with a resistance band. And clamshells are also helpful," Kale says. You do this exercise by lying on your side with your knees bent and raising and lowering only your top knee while keeping your feet together.

In time, you can restore balance to the body and reduce pain. "Pain comes on because of an imbalance from tight or weak muscles," Dr. Elson says. "If you can restore balance, you can help the body function better and eliminate pain." For more information, check out the Harvard Special Health Report The Joint Pain Relief Workout (/jprw).