Ankylosing Spondylitis Center

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The Universal Guide to Ankylosing Spondylitis: Everything you ever wanted to know, straight from the experts.

In This Article: What Is Ankylosing Spondylitis?   |    Causes   |    Symptoms    |    Diagnosis   |    Treatment   |    Living with AS   |    Sources

If you’ve been diagnosed with ankylosing spondylitis (AS) or suspect you might have it, you may be in a lot of pain. Fortunately, treatment for this form of spinal arthritis has come a long way over the last few decades. Newer therapies often mean less inflammation, better-controlled symptoms and even a slower progression of the disease.

“That’s an important thing to know, because when people hear ‘ankylosing spondylitis,’ they will Google it and find pictures of patients with end-stage disease from the days when we did not have treatments. That can be frightening,” says Joerg Ermann, MD, an associate physician in the Division of Rheumatology, Inflammation and Immunity at Brigham and Women’s Hospital in Boston.

So, what is AS exactly? What causes it, and how is the condition diagnosed? Perhaps most important, what treatments can help AS patients achieve less pain and improve their quality of life?

What Is Ankylosing Spondylitis?

Ankylosing spondylitis is also known as Marie-Strumpell disease or Bechterew’s disease. It’s a form of inflammatory arthritis that primarily affects your spine. After several years, the bones in the spine, called vertebrae, may fuse together. When this happens, the spine becomes stiff and less flexible.

  • Ankylosis:  joints fuse together and become unmovable
  • Spondylitis: inflammation involving the spine’s vertebrae and facet joints

Healthy spine versus one with ankylosing spondylitisWhen vertebrae or other bones/joints fuse together, the spine becomes stiff and immobile. Photo Source:

AS often develops in the sacroiliac joints (SI joints), which connect your lower spine to your pelvic bones. It can also develop in other parts of your spine and cause symptoms and conditions elsewhere in your body.  

Sometimes, AS can affect your posture. For example, you may develop a hunched back. Doctors call this kyphosis, an abnormal forward position of the upper spine.

What Are Possible Ankylosing Spondylitis Causes?

Causes of Ankylosing SpondylitisThe common causes of Ankylosing Spondylitis.

Inflammation is your immune system’s way of fighting illness and injury. During an inflammatory response, chemicals and cells in your bloodstream rush to protect healthy tissue and repair any damage done. This can cause pain and swelling, among other symptoms.

When you have AS, the inflammatory response doesn’t work like it should. Instead, inflammation is triggered in healthy parts of your body—including your spine and SI joints.

We don’t know exactly what causes AS, but several factors may increase your risk.

Gender. Experts used to believe men were up to nine times more likely to have AS than women. But in recent years, research has shown the difference is much smaller than we thought—if there is one at all. One possible reason: Women may have been misdiagnosed or underdiagnosed in the past.

Family history. If your parents or grandparents have AS, you’re more likely to develop it yourself.

HLA-B27: Human leukocyte antigen B27 (HLA-B27) is a protein you may have in your blood. It’s found in the vast majority of Caucasian people with AS, and about half of Black people with AS.

Having the HLA-B27 protein doesn’t mean you have AS—and vice versa. You can have AS without this marker, and you can have this marker without developing AS.

What Are Typical Ankylosing Spondylitis Symptoms?

Symptoms of AS can start at any age, but they often begin before 45. They may differ greatly from one person to another, though some are very common—including those on this ankylosing spondylitis symptoms checklist:

Chronic pain and stiffness. These symptoms typically occur in the lower back first, and frequently the hips and buttocks, too. The discomfort usually builds up slowly, over a period of weeks or months. It can be located on one side of the body, both sides, or go back and forth between sides.

Some people experience intermittent back pain, and others have serious pain and stiffness for long periods of time. Almost all cases of AS are characterized by acute pain followed by temporary remission when symptoms subside.

Discomfort at certain times of the day. “A lot of the time, patients report nocturnal back pain,” says Namrata Singh, MD, Assistant Professor in the Division of Rheumatology at the University of Washington Medical School in Seattle. Many people with AS feel sore and stiff first thing in the morning, as well.

Improvement with movement. “The other hallmark is the pain gets better as your day goes on or you move around, and the pain gets more severe or you get more stiff as you sit more,” Dr. Singh explains.

Inflammation in key areas. If you experience discomfort in different parts of your body, AS could be to blame. The places most often affected by AS include:

  • SI joints
  • Lower back vertebrae
  • Hip and shoulder joints
  • The entheses, or areas where tendons and ligaments attach to bones, mainly in your spine but sometimes at the back of your heels
  • Cartilage around your ribs and breastbone

Ankylosing spondylitis SI joint inflammationAS often causes SI joint inflammationAdditional body-wide symptoms. Early on, someone with AS may also experience fatigue, loss of appetite, low fevers and mild anemia.

Other Conditions May Develop

When you have AS, you may be at increased risk for certain other inflammatory conditions. Up to 40% of those with AS will develop uveitis, a type of inflammatory eye disease that can cause redness, pain, and vision changes.

Sometimes, says Dr. Singh, patients will present with eye problems first, and the subsequent workup will reveal signs of AS. “We are referred to patients who are actually re-diagnosed with ankylosing spondylitis from ophthalmology,” she explains.

About 10% of AS patients have inflammatory bowel disease (IBD), an umbrella term describing two conditions: Crohn’s disease and ulcerative colitis. Symptoms can include abdominal pain, diarrhea, and bloody stools.

Less often, you can develop more serious health problems with AS. Inflammation in your body can affect your heart, which may increase your risk of cardiovascular events such as heart attack and stroke. Pulmonary issues are also linked with AS, since stiff ribs can affect lung function and the ability to breathe.

How Can You Get an Ankylosing Spondylitis Diagnosis?

Since symptoms often come on slowly and can resemble those of other conditions, it frequently takes years for AS to be correctly diagnosed. But a diagnosis is critical to getting the right treatment early on. If you believe you might have AS, your best bet is to see a doctor called a rheumatologist, who specializes in musculoskeletal and some autoimmune diseases.

“The big question we are asked is, ‘Do you have a blood test you can do for me to diagnose this?’” says Dr. Singh. “And the answer usually is no.”

Instead, your rheumatologist will use a combination of methods to pinpoint AS and rule out other conditions, called a differential diagnosis. These methods may include the following.

Physical exam. To get to the root of your problems, your provider will look for pain, swelling and tenderness at certain points around your body, such as your back, SI joints, pelvis and heels. They’ll also check for mobility limitations in your spine and other joints. This may involve a few simple, in-office tests requiring you to perform certain movements.

During a Schober test, for example, your provider would assess your lower back flexibility by asking you to bend forward. And for a Gaenslen test, you would be asked to lie down and flex one of your knees while your provider applies pressure to your other leg. This helps to evaluate pain in the SI joints.

Medical history. This will entail a rundown of your symptoms, as well as their severity, duration and location. Problems like uveitis and IBD will be considered as well.

Bloodwork. Your doctor will look for the HLA-B27 protein, as well as other markers of inflammation. Evidence of inflammation may hint at AS, but it could also be a number of other conditions.

Imaging. The earliest changes your doctor can spot on an X-ray are likely in the SI joints, though it may be years before there is enough damage to show up. Magnetic resonance imaging (MRI) and computed tomography (CT) are more sensitive tests for AS. These can detect earlier stages of the disease, such as inflammation of the joints before bone changes occur.

What Are Ankylosing Spondylitis Treatment Options?

There is no cure for AS, but several different therapies can ease pain, decrease inflammation, improve function, and slow the progression of the disease.

Pain relievers. Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve) are often recommended to relieve painful AS symptoms. An analgesic like acetaminophen (Tylenol) may also be used.

Disease Modifying Antirheumatic Drugs (DMARDs). This class of drug is prescribed to help reduce inflammation and slow the progression of several kinds inflammatory and/or autoimmune diseases, including AS. DMARDs prescribed to treat AS include methotrexate and sulfasalazine (Azulfidine).

Biologics. These are special kinds of DMARDs created from living cells. Biologics for treating AS are administered via infusion at a medical facility or by self-injection at home. There are several your doctor may recommend, such as: adalimumab (Humira), certolizumab (Cimzia), secukinumab (Cosentyx), and ixekizumab (Taltz).

Exercise. Physical therapy and exercise are very important if you have AS. Not only can gentle stretching and exercise help relieve back and/or neck stiffness, they can help you stay as mobile as possible. Your physical therapist can prescribe a home stretching and exercise program and teach you good practices for proper posture. Bonus: Physical activity can boost your cardiovascular health and mood as well.

Dr. Ermann warns that people with AS should avoid certain types of exercise, since it increases the risk for spinal fractures. These include contact sports and activities that pose a raised threat of spinal injury, such as skiing and snowboarding.

Ankylosing spondylitis exerciseBeware activities that carry an increased risk of spine injury, like skiing.

Surgery. Though most people with AS can be treated successfully without surgery, surgery for ankylosing spondylitis may be necessary in certain cases. A surgeon will help decide what kind of procedure you need depending on your symptoms, age, overall health and specific situation, among other factors.

  • Laminectomy. Sometimes, AS can cause nerves or the spinal cord itself to become compressed. This may result in pain, weakness, numbness or tingling. To ease this pressure, your surgeon may perform a laminectomy, which involves removing the back arch of the vertebral bone, called the lamina.
  • Osteotomy. When someone with AS develops a curved spine, it can seriously damage their day-to-day function and quality of life. During an osteotomy, bone is cut and reshaped for better posture and movement. Osteotomy for AS is considered to carry risks and is rare in the United States.
  • Spinal instrumentation and fusion. People with AS have a significantly higher risk of spinal fracture than people without AS. “That needs to be fixed surgically in most cases,” says Dr. Ermann, “because often these fractures are not stable and the represent a threat to the spinal cord.”

If bones in your spine have been damaged or you’ve had an osteotomy, your surgeon may use instrumentation—such as wires, screws, rods, bars, or cages—to fuse surrounding bone together. This keeps your spine stable and protects the spinal cord from being harmed.

  • Joint replacement. Knee, shoulder or hip replacement may be necessary “after years of treatment—in particular in those patients who developed disease before the biologics became available,” Dr. Ermann explains.

Surgery for AS takes place in a hospital. Once it is complete, depending on your procedure and your overall health, you may begin walking with assistance within days—or even hours. Some surgeries require that you spend multiple nights in the hospital.

At home, no matter what kind of surgery you’ve had, it’s important to follow all directions given by your healthcare team. You may have to wear a brace or collar, limit your activity, or even bathe a certain way. Medication will likely be recommended to control pain resulting from the procedure. Sticking closely to instructions can greatly affect the speed and success of your recovery.

What Are Some Tips for Living with Ankylosing Spondylitis?

Living with AS can be challenging, especially if it’s left untreated. As time goes on and the disease progresses, you might need to pass on certain plans or activities. You may not be able to sleep well. You could have a harder time in the weight room, in the yoga studio, on the athletic field—or even just keeping up with your kids. Sometimes, people with AS develop depression or anxiety.

However, there are steps you can take to reduce the impact of the disease on your body and mind. These are just a few.

Quit smoking. Not only is smoking a risk factor for AS, it can worsen your disease, reduce the effectiveness of treatment, not to mention, duh, it can kill you. Come on, you know what you need to do here, but if you need us to spell it out: Q-U-I-T

Focus on healthy eating. Though there is no special diet designed for people with AS, a diet focused on whole, nutritious foods can help tame inflammation. It can also help you maintain a healthy weight, which is key to managing to the disease. You’ll want to include fruits, vegetables, whole grains, and lean proteins, and limit alcohol, sugar, sodium, and saturated fats. If you need more structure than these general guidelines, reach out to a dietitian who can customize an eating plan around healthy foods you will enjoy.

Consider assistive devices. If walking hurts your back, be open to using a cane, walker, and orthopedic inserts for your shoes. Remember, gentle activity can help relieve symptoms, while being sedentary will contribute to them. There are also assistive devices that can make it more comfortable for you to reach for items in your home, get in your car, and more.

Ankylosing spondylitis assistive devicesAssistive devices such as canes and walkers can help keep you moving when you have AS.

Try simple home treatments. Cold therapies can help reduce inflammation, and heat can help relieve joint stiffness. Look for packs at your local drugstore.

Prioritize your mental health. Psychological and physical wellbeing are closely connected. Find people with whom you can speak openly about your AS, from friends and family to support groups. Look for stress relievers that work for you. If your situation becomes overwhelming, reach out to your doctor or a mental health professional for help.

Use complementary therapies with caution. Though there isn’t much research to support their effectiveness, some people with AS find that complementary therapies, such as acupuncture and gentle massage, help relieve symptoms. Your doctor can help decide what’s safe for you and may even be able to refer you to a practitioner with relevant experience. Be aware that experts strongly recommend against chiropractic care for AS due to a high risk for injury.

Once you’ve been diagnosed with AS and begin to receive treatment, it’s important to stay in close communication with your rheumatologist and other members of your healthcare team. Keep an eye out for new symptoms and alert your providers to any significant changes between regular visits. Always follow your treatment plan closely, too, and take care not to skip appointments. Through diligence and dedication, you can improve your chances of a better AS outcome.


What is AS: Mayo Clinic. (N.d.) “Ankylosing Spondylitis.”

Causes: Brigham and Women’s Hospital. (2007) “Standard of Care: Ankylosing Spondylitis.”

Symptoms: Mayo Clinic. (N.d.) “Ankylosing Spondylitis.”

Diagnosis: Brigham and Women’s Hospital. (2007) “Standard of Care: Ankylosing Spondylitis.”

Arthritis Foundation. (n.d.) “Axial Spondyloarthritis.”

Canadian Spondylitis Association. (n.d.) “Ankylosing Spondylitis.”

Canadian Spondylitis Association. (n.d.) “Managing Spondylitis.”

Casper Webers, Ivette Essers, et al, “Gender-attributable differences in outcome of ankylosing spondylitis: long-term results from the Outcome in Ankylosing Spondylitis International Study.” Rheumatology, Volume 55, Issue 3, March 2016, Pages 419–428.

Johns Hopkins Medicine. (n.d.) “Laminectomy.”

MedlinePlus. (n.d.) “Ankylosing Spondylitis.”

National Health Service (UK). (2019) “Ankylosing Spondylitis: Causes.”

National Institute of Arthritis and Musculoskeletal and Skin Diseases. (2020) “Ankylosing Spondylitis.”

Physiopedia. (n.d.) “Gaenslen Test.”

Physiopedia. (n.d.) “Schober Test.”

Saad B. Chaudhary, Heidi Hullinger, and Michael J. Vives. “Management of Acute Fractures in Ankylosing Spondylitis. ISRN Rheumatology. 2011; 2011: 150484.

The Spine Hospital at The Neurological Institute of New York. (n.d.) “Osteotomy.”

Spondylitis Association of America. (2019.) “2019 Axial Spondyloarthritis Treatment Recommendations: A Brief Overview For Patients And Families.”

Spondylitis Association of America. (n.d.) “Complementary Treatments.”

Spondylitis Association of America. (n.d.) “Diagnosis of Ankylosing Spondylitis.”

Spondylitis Association of America. (n.d.) “Diet's Effect on Spondylitis Symptoms.”

Spondylitis Association of America. (n.d.) “Exercise.”

Spondylitis Association of America. (n.d.) “Most Common Symptoms.”

Spondylitis Association of America. (n.d.) “Overview of Ankylosing Spondylitis.”

Spondylitis Association of America. (n.d.) “Possible Complications: How Is a Person Affected?”

Spondylitis Association of America. (n.d.) “Spondyloarthritis: Autoimmune or Autoinflammatory?”

Spondylitis Association of America. (n.d.) “Spondyloarthritis in Women.”

Spondylitis Association of America. (n.d.) “Treatment of Spondyloarthritis.” (2020) “Patient education: Axial spondyloarthritis, including ankylosing spondylitis (Beyond the Basics).”

UW Medicine—Orthopaedics and Sports Medicine. (n.d.) “Ankylosing Spondylitis.”

Weill Cornell Brain and Spine Center. (2020) “Ankylosing Spondylitis.”

Updated on: 03/30/21
Ali A. Baaj, MD
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