Hip pain is a common symptom of ankylosing spondylitis (AS). Some evidence suggests that, after the back, the hip is the second most common area where AS symptoms begin.

This information comes from a 2022 study of 60 adults with AS.

AS is a form of spondyloarthritis. This is a type of inflammatory arthritis that specifically affects the joints and ligaments. It most commonly affects the spine, but it can also affect the pelvis, buttocks, neck, and other joints.

Read on to learn more about AS hip pain, including what it feels like, treatment options, and exercises to help ease symptoms.

An older woman sat on a bed with her hand on her back due to AS hip pain.Share on Pinterest
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AS often causes stiffness and pain that worsens with inactivity. The pain may improve when a person moves around and be at its worst after sitting or lying down for a long time. Over-activity like strenuous exercise can also trigger these symptoms.

When a person has AS-induced hip pain, their pain typically occurs in the sacroiliac (SI) joint, which is where the bottom of the spine meets the pelvis. The pain may move from side to side or affect both sides.

AS is a type of inflammatory arthritis, meaning the disease causes joint inflammation, which causes pain.

Inflammation is part of the body’s immune response to damage or injury. Usually, it rises while the body heals, then gets better on its own. But in AS, the inflammation remains high.

Scientists are not sure why this happens, but research suggests there’s a genetic link. Many people with AS have a gene known as HLA-B27. This gene seems to raise a person’s risk of developing AS, but it does not guarantee they will.

To diagnose AS, a doctor will ask a person about their symptoms. They may also ask about the person’s medical or family history to see if there is a pattern of AS or arthritis presenting.

Next, the doctor may perform a physical examination to see where the pain is and how it affects movement. To get an accurate view of the hip joints, they may order an X-ray or MRI scan.

There is no specific blood test to diagnose AS, but a doctor may order tests to identify markers of inflammation or the HLA-B27 gene.

There’s currently no cure for AS. However, treatment can help relieve pain and stiffness. It may also slow or stop the disease progression. The ultimate goal of treatment is delaying complications and joint damage.

Treatment may involve a combination of:

Medications

Medications for AS can include:

  • nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, naproxen, or diclofenac
  • tumor necrosis factor (TNF) blockers, such as adalimumab (Humira), certolizumab pegol (Cimzia), or etanercept (Enbrel)
  • interleukin-17 (IL-17) inhibitors, such as secukinumab (Cosentyx) or ixekizumab (Taltz)
  • JAK inhibitors, such as tofacitinib (Xeljanz) or upadacitinib (Rinvoq)

People can take NSAIDs orally. NSAIDs come with some risks, including gastrointestinal bleeding and kidney injury.

People receive TNF blockers and IL-17 inhibitors as injections or IV infusions. They suppress the immune system, meaning a person is more vulnerable to infections.

Physical exercise

Physical therapy is an important part of AS treatment. Some types of exercise that may help include:

  • Range of motion exercises: These exercises involve moving the joints through their full range of motion. Practicing these exercises daily can help reduce stiffness and maintain mobility.
  • Low impact aerobic exercise: This includes activities like walking, using a stationary bicycle, or water aerobics. For the latter aerobic exercise, the water provides gentle resistance while reducing the gravitational impact on the joints.
  • Strength training: Stronger muscles can support the joints, including the spine and hips, more effectively. Try to do strength training 2–4 times per week with rest days in between.
  • Balance training: Balance training can also strengthen the muscles, particularly the smaller muscles in the body. Try to perform these exercises 3–5 times per week.

A physical therapist with expertise in AS can help people create a tailored exercise plan. If any exercise worsens AS symptoms, it’s important to stop and rest until the symptoms improve, and contact a health professional for advice.

Here are some specific exercises that may help manage AS hip pain. Check with a doctor or physical therapist before trying any new exercises.

People may find it helpful to start with a lower number of repetitions, or less time holding a position, before working their way up.

Chair stand

  1. Place a chair with a back against a wall.
  2. Sit on the edge of the seat.
  3. With the heels planted on the floor, slowly stand up and sit back down.

Bridge pose

  1. Lie flat on the floor and bend the knees with the feet hip-width apart.
  2. Put the arms straight at one’s sides, palms on the floor.
  3. Slowly raise the buttocks off the floor and hold for a few seconds.
  4. Slowly lower the buttocks back down and repeat.

Hip extensions

  1. From a standing position, place a hand on a chair, table, or countertop for balance.
  2. Extend one leg behind the body. Lift this leg as high as possible without bending the spine.
  3. Hold the leg in the air, then lower it.
  4. Repeat the steps for each leg.

Hip rotations

  1. Lie flat on the back and bring the knees to the chest with arms flat on the floor.
  2. Slowly rotate both knees to the right while looking to the left.
  3. Hold the position, then bring the knees back to the center.
  4. Drop both knees to the left while looking to the right.
  5. Hold the position, then bring the knees back to center. Repeat, alternating from side to side.

Inner leg stretches

  1. Lie on the front.
  2. Reach the arms backward, grabbing the ankles.
  3. Gently pull the ankles toward the shoulder blades and hold.
  4. Let go of the ankle and lower the legs and arms back down to the floor. Repeat.

Hip and low back stretches

  1. Lie flat on the back and tuck the chin in toward the chest.
  2. Bring the knees into the abdomen while keeping the spine flat on the floor.
  3. Pull the knees gently to stretch them as close to the chest as possible.
  4. Hold, then release, extending the legs back down to the floor. Repeat.

AS hip pain may worsen when a person lies still, which can wake them up at night. To try and reduce the pain:

  • invest in a high quality mattress that distributes body weight evenly
  • replace sagging or overly soft mattresses
  • pay attention to sleeping position, as this may be exacerbating pressure on the hips
  • try sleeping flat on the back with a thin pillow or folded towel under the head
  • avoid sleeping on the stomach

Hip pain in AS is common. It may affect the SI joint, where the spine meets the pelvis bones. Although it’s not the most common place where AS begins, it can be where the pain starts.

With treatment, many people with AS can manage their pain and have fulfilling lives.

If the pain is significant despite all of these tips and interventions, be sure to contact a doctor.