Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a type of arthritis that affects joints in your spine. Healthcare providers sometimes call it axial spondylarthritis.

It often starts in the joints where your spine connects to your pelvis (sacroiliac joints). But over time, it can affect your whole spine, all the way up to your neck.

It’s less common, but ankylosing spondylitis can develop in other joints, including your:

• Shoulders
• Hips
• Knees

AS causes pain and stiffness in your spine. Visit a healthcare provider if you’re experiencing lower back pain, especially if it’s getting worse or making it hard to do your usual daily activities.

Symptoms of ankylosing spondylitis

Lower back pain from sacroiliitis (painful inflammation in your sacroiliac joints) is the most common AS symptom.

The pain can spread from your sacroiliac joints to your:

• Hips
• Butt
• Neck

Other ankylosing spondylitis symptoms can include:

• Stiffness or trouble moving your hips and lower back, especially first thing in the morning or after you’ve been resting in one position for a long time
• Fatigue
• Shortness of breath
• Appetite loss or unexplained weight loss

You may have other symptoms if you have AS and certain other conditions:

• Diarrhea, if you have inflammatory bowel disease
• Skin rashes, if you have psoriasis
• Vision problems, if you have iritis or uveitis

Ankylosing spondylitis causes

Ankylosing spondylitis is an autoimmune disease. It happens when your immune system attacks your body instead of protecting it. More specifically, your immune system irritates tissue in your spinal joints. This leads to inflammation and damage that causes pain and other symptoms.

Experts aren’t certain what makes your immune system attack your body, leading to ankylosing spondylitis. Studies have found that specific genetic variations are closely linked to having AS.

More than 60 changed genes might be linked to it. One example is the human leukocyte antigen-B (HLA-B27) gene. More than 9 in 10 people who are white and have AS also have a mutated HLA-B27 gene.

Risk factors

Anyone can develop ankylosing spondylitis. But you may be more likely to develop it if you:

• Are younger than 40 (more than 8 in 10 people with AS are diagnosed when they’re around 30)
• Are male
• Have a close biological relative with AS, especially a parent

Having certain health conditions can increase your AS risk, too, including:

• Crohn's disease
• Ulcerative colitis
• Psoriasis

What are the complications of ankylosing spondylitis?

You’ll have a higher risk of spinal fractures if you have AS.

Other complications can include:

• Bones in your spine fusing together, also known as ankylosis
• Kyphosis
• Osteoporosis
• Eye and vision issues, like uveitis
• Heart issues, like aortitis, arrhythmias and heart block
• Nerve damage

How doctors diagnose ankylosing spondylitis

A healthcare provider will diagnose ankylosing spondylitis with a physical exam and some tests. They’ll examine your body and ask about any symptoms you’ve had. Tell your provider when you first noticed pain or other symptoms. Let them know if the symptoms are worse at certain times of day or during any activities.

You might need to visit a rheumatologist, a healthcare provider who specializes in treating arthritis and autoimmune diseases.

No single test can confirm you have AS. Your provider might use a few tests to help diagnose it, including:

• X-rays of your spine
• MRI scan of your sacroiliac joints and spine
• Blood tests to look for genetic changes or inflammatory markers

Ankylosing spondylitis treatments

Your healthcare provider will suggest treatments to manage AS symptoms and reduce their impact on your daily routine.

Common treatments for ankylosing spondylitis include:

• Exercise: Regular physical activity can reduce stiffness and slow down AS progression. Many people experience more severe pain when they’re inactive. A physical therapist can suggest specific stretches and exercises to help strengthen the muscles that support your back and spine.
• NSAIDs: Over-the-counter medications like ibuprofen and naproxen relieve pain and reduce inflammation. Talk to your provider before taking NSAIDs for more than 10 days in a row.
• Biologic DMARDs and JAK inhibitors: These prescription medications reduce inflammation and pain. They might also stop AS from getting worse.
• Corticosteroids: These are prescription anti-inflammatory medications. You might need cortisone shots.
• Surgery: It’s rare to need surgery to treat AS. Your provider will usually only suggest it if you have severe symptoms that don’t get better after trying other treatments.

When should I see my healthcare provider?

Visit a healthcare provider if you notice new or worsening symptoms. Talk to your provider if it feels like your treatments aren’t working as well as they used to.

See a healthcare provider if you experience any of the following symptoms:

• Chest pain
• Difficulty breathing
• Vision problems
• Severe back or joint pain
• Unusually stiff or rigid spine
• Unexplained weight loss

What can I expect if I have ankylosing spondylitis?

You should start feeling better soon after starting treatment. The symptoms might not go away completely, but they should improve over time. Exercise and physical therapy are gradual processes, and medications may need some time to take effect.

You should expect to manage symptoms and take medications for a long time — maybe the rest of your life. There’s no cure for AS. But some people have periods of remission where they have fewer (or milder) symptoms. Even if it’s been a while since you experienced symptoms, there’s always a chance they could come back.