Ankylosing spondylitis is an inflammatory condition that affects the spine and areas where tendons and ligaments attach to bone. However, it has many other possible symptoms beyond the spine.

Hip pain and stiffness is a possible symptom of ankylosing spondylitis (AS).

In cases of chronic hip involvement, mobility may become a problem. However, with a timely diagnosis and treatment, inflammation and pain can often be managed and lowered.

AS treatments include medications, lifestyle changes, and surgery in severe cases. These aim to improve your quality of life, maintain your mobility, and help you avoid long-term disability.

The inflammation associated with AS usually first triggers pain in the joints, tendons, and ligaments of the lower spine. This includes the sacroiliac (SI) joint, where the spine connects to the pelvis.

The clinical terms for inflammation of the areas where tendons and ligaments attach to bones is enthesitis or enthesopathy. People with AS can experience enthesitis in the hips and other sites, including the:

  • ankles
  • feet
  • knees
  • ribs
  • shoulders

The Spondylitis Association of America reports that about 1 in 3 people with AS experience hip and shoulder pain. When the hips are affected, the pain tends to build gradually. In some cases, you may feel pain originating from the hip joints lower down on the legs and knees. Many people with AS who have hip pain experience it bilaterally, meaning it happens in both hips.

Hip pain with AS can be due to enthesitis or to arthritis in the hip itself. A 2016 Korean study found over 12% of participants with AS had hip arthritis. The authors stated that around 24% to 36% of people with AS had clinical hip involvement, meaning they reported symptoms of hip pain. The number of people who had radiographic (X-ray) hip changes was smaller. This is because inflammation can take time to present on X-ray, among other factors.

A 2021 Chinese study investigated whether X-ray or MRI showed changes in participants with AS. The authors reported AS hip pain is often located in the groin area and, in addition to spine-related pain, is a leading cause of mobility issues in people with AS. The study found that 42% of participants with minimal-to-no hip pain still had visible MRI lesions. The researchers also observed hip joint narrowing in the majority of the cohort.

Overall, changes due to AS can take years to show up on an X-ray. Even though MRI often shows inflammation sooner, it isn’t perfect at detecting it. This means that often, by the time imaging shows inflammatory changes to the spine, SI joint, hips, or elsewhere, AS has not been effectively managed.

Because hip pain can be caused by a variety of injuries and medical conditions, getting a thorough diagnosis is important to make sure your treatment plan is appropriate.

Rheumatologists are the doctors who treat AS, in addition to other conditions like rheumatoid arthritis and osteoporosis. If you already have an AS diagnosis and are experiencing hip pain, your doctor may consider adjusting your medications, ordering new imaging tests, or recommending physical therapy.

If you are experiencing hip pain and being evaluated for AS, here’s what to expect.

Your first appointment will likely include:

  • Physical examination: Your doctor will ask about current symptoms and may test and manipulate your joints to check for mobility, stiffness, or swelling.
  • Review of your medical history: This includes any medications you currently take, other health conditions, and your family medical history. Rheumatologists often require lengthy new patient paperwork so they can have as much information as possible.
  • X-rays: AS imaging usually focuses on the back and hips, unless you have symptoms in other joints. However, radiographic changes due to AS may not show up for years.
  • MRI scans: MRIs can usually identify signs of AS earlier than X-rays, although many people may still not show inflammatory changes, especially early in disease progression.
  • Blood tests: The biomarker human leukocyte antigen B27 (HLA-B27) is common in people with AS. It occurs in around 90% of those with the disease. However, the majority of people in the general population with HLA-B27 do not have AS.

The main goals of AS treatment are to relieve pain and improve mobility while also preventing complications.

Home remedies

Spine and hip pain due to injuries often requires rest to heal. But the National Institute of Arthritis and Musculoskeletal and Skin Diseases says that inflammatory pain due to AS often worsens with rest. Regular physical activity can help lessen pain and improve mobility in people with AS.

Speak with a doctor before starting any new exercise or stretching program, especially if you have other medical concerns that affect your cardiovascular health and joints.

Other home remedies to consider include:

  • ice and heat, including cold packs to reduce swelling around inflamed areas and warmth to ease pain and stiffness
  • foam rolling
  • stretching
  • weight loss, if advised by your doctor, which can reduce the burden on your joints

People with more severe AS, especially AS that affects posture and the ability to bend at the hips, may benefit from physical therapy with a focus on postural training.

Other important approaches to take when managing AS are:

Medications

If you need medications to ease joint pain, nonsteroidal anti-inflammatory drugs (NSAIDs) may be helpful. You can purchase NSAIDs, including ibuprofen (Advil) or naproxen (Aleve), over the counter.

If NSAIDs are not enough, your doctor may prescribe tumor necrosis factor (TNF) inhibitors. Also known as TNF blockers, these are a subgroup of biologic therapies. In addition to treating AS, these drugs are commonly used to treat rheumatoid arthritis, Crohn’s disease, psoriasis, and several other medical conditions.

Some of the more widely prescribed biologics for AS include:

Many of these medications have “biosimilar” versions with different names, and those may be the medications prescribed.

All medications come with risk of side effects. It’s important your doctor knows about any of your other health conditions and current medications when making a decision regarding your prescription.

Corticosteroid injections directly into one or both hip joints may occasionally be considered to lower inflammation and pain.

Hip replacement surgery

If damage to the hip joint is significant, making walking and other everyday functions painful or impossible, hip replacement surgery may be considered. Usually, doctors only consider hip replacement after conservative treatments haven’t been effective. It is also used for people with hip injuries or other types of arthritis, including rheumatoid arthritis and osteoarthritis.

A 2019 review of studies concluded that total hip replacement offered “significant improvement in hip function, patient satisfaction and patient mobility” for people with AS, and high survival rates.

However, like any surgery, hip replacement has some risks. These include dislocations and fractures, in addition to general surgery risks like infection and pain. In people with AS, increased bone growth can also occur.

If you experience hip pain, it may or may not have anything to do with AS. Or, you can have AS and have no hip pain at all.

Another type of arthritis, called osteoarthritis, is a common cause of hip pain. The condition develops after considerable wear and tear on the joint. It particularly affects older adults and athletes who played high impact sports, such as football, basketball, and long-distance running.

Other possible causes of hip pain include:

Your age may also be a tip-off as to the cause of your hip pain. AS tends to first appear by the age of 45, though it’s not unusual for children or teens to start having symptoms. Osteoarthritis, which may present with similar symptoms, is more common in older adults.

AS currently has no cure, but treatments and lifestyle changes are available to help you manage symptoms. Effectively managing your AS can improve your mobility and quality of life.

Hip pain due to AS can be treated with a combination of home remedies, like ice, heat, and stretching, and medical interventions, such as medication and even surgery, if necessary.

If you’re experiencing pain and stiffness in one or both hips, speak with a doctor. Whether you have AS, getting a timely diagnosis can help prevent long-term joint damage and improve your outlook.