Spondyloarthritis (Spondyloarthropathy)

What is spondyloarthritis?

Spondyloarthritis (SpA) means arthritis of the spine (spondyl-). Arthritis is pain and stiffness in your joints. Spondyloarthritis affects the joints connected to your spine — the facet joints between your vertebrae and the sacroiliac joints that connect your spine to your pelvis. Lower back pain is the most common symptom. But spondyloarthritis can also affect other joints and cause other symptoms.

Spondyloarthritis isn’t one condition but a group of conditions with common features. They begin with arthritis of the spine, but they don’t end there. Healthcare providers also describe these conditions as spondyloarthropathy, which means disease (-pathy) in the joints (arthro-) of the spine. These conditions are distinct from osteoarthritis and rheumatoid arthritis, which can also affect the joints in your spine.

Some key features of spondyloarthritis (spondyloarthropathy) are:

• It’s rheumatic. Spondyloarthritis is a rheumatic disease, which means it’s an inflammatory type of arthritis. Chronic inflammation causes the symptoms of pain and swelling in your joints. Unlike osteoarthritis, which is a product of wear and tear on your joints, inflammatory arthritis is usually a type of autoimmune disease. That means your immune system causes the constant inflammation in your joints — and often causes it in other places in your body, too.
• It’s not RA. Despite being a type of rheumatic arthritis, it’s not the most famous type, which is rheumatoid arthritis (RA). We know this because people with spondyloarthritis don’t test positive for rheumatoid factor, the antibody that’s typical of RA. This is why healthcare providers sometimes refer to spondyloarthritis as “seronegative spondyloarthropathy.” “Seronegative” means the blood test for RA is negative. There’s no known SpA antibody.
• Enthesitis. Inflammation in your entheses (enthesitis) is a hallmark of spondyloarthritis that healthcare providers will look for during diagnosis. Entheses are fibrous connective tissues that act as the “joints” where your tendons and ligaments insert into your bones. Spondylarthritis can cause enthesitis in different places in your body. Heels and knees are common sites.
• A gene called HLA-B27. Between 80% and 95% of people with spondyloarthritis who are of northern European descent have a gene called HLA-B27. It isn’t as common in people of other ethnicities who have spondyloarthritis. And the gene alone doesn’t cause the disease. But it’s common enough that your healthcare provider might test for it to help make your diagnosis.

How common is spondylarthritis?

Although it’s not as well known, spondyloarthritis is actually more common than rheumatoid arthritis. An estimated 0.5% to 2% of the population worldwide has some form of spondyloarthropathy.

What are the different types of spondyloarthritis (spondyloarthropathy)?

Several distinct diseases fall under the general heading of spondylarthritis. Healthcare providers separate them into two main categories: axial spondyloarthritis and peripheral spondyloarthritis.

Axial spondyloarthritis

Axial spondyloarthritis is spondyloarthritis that mainly affects the joints in your axial skeleton: your neck, chest and spine. As it progresses, it may involve other joints and even organs.

Ankylosing spondylitis is a severe form of axial spondyloarthritis that causes visible changes to the bones in your spine, called ankylosis. It’s the most common type of spondyloarthritis overall.

Peripheral spondyloarthritis

Peripheral spondyloarthritis affects your peripheral joints and entheses first — the ones on the outside of your axial skeleton (like your limbs). As it progresses, it may or may not go on to affect your spine.

Peripheral spondyloarthritis also typically involves inflammation in other organs. Different types tend to affect different organs — like your eyes, skin or bowels — but symptoms can overlap. Types include:

• Psoriatic arthritis. Psoriatic arthritis is arthritis that occurs together with psoriasis, an autoimmune skin condition that causes an inflammatory skin rash. It most often affects the small joints in your hands and feet, causing painful swelling in your fingers and toes.
• Enteropathic arthritis. Enteropathic arthritis is arthritis that occurs together with inflammatory bowel disease (IBD). Enteropathic means that it’s related to your intestines.
• Reactive arthritis. Reactive arthritis is an autoimmune reaction to an infection in your intestines or urinary tract. It may affect your eyes, skin, bladder, genitals or bowels. It’s typically temporary, but it can last up to 12 months, and some people develop chronic arthritis.

Undifferentiated spondyloarthritis

Undifferentiated spondyloarthritis is the diagnosis when your symptoms fit the profile of spondyloarthritis in general, but they don’t quite fit the profile of any specific subtype.

Juvenile spondyloarthritis

Juvenile spondyloarthritis is spondyloarthritis that develops during childhood — usually before age 16. Children may develop a specific type of spondyloarthritis or symptoms from many types.

What are the symptoms of spondyloarthritis?

Symptoms of different types of spondyloarthritis often overlap. While some symptoms are more characteristic of certain types of spondyloarthritis than others, all symptoms can occur with any type.

Symptoms may include:

• Lower back pain that may spread to your butt (sacroiliitis).
• Stiffness that’s worse in the morning and gets better with movement.
• Mid- and upper back pain, musculoskeletal chest pain or neck pain.
• Gradual curvature of the spine.
• Pain and stiffness in the joints of your limbs — hips, shoulders, knees, elbows, wrists or ankles.
• Severely swollen fingers or toes (“sausage fingers” or dactylitis).
• Gastrointestinal symptoms, like abdominal pain and diarrhea.
• Pain and inflammation in your urinary tract.
• An itchy, flakey skin rash (psoriasis).
• Nail pitting (nail psoriasis).
• Fatigue.
• Loss of appetite.
• Eye inflammation (uveitis).
• Mouth sores.
• Heel pain (due to enthesitis).
• Bone spurs.

Symptoms of spondyloarthritis tend to appear earlier than other types of arthritis — usually before the age of 45. They begin slowly and may pile on gradually. In most cases, symptoms continue indefinitely.

What causes spondyloarthritis?

Chronic inflammation in your joints and other tissues causes the symptoms of spondyloarthritis. Your immune system generates the chronic inflammation automatically. This is called autoimmune disease.

Researchers don’t entirely understand why autoimmune diseases occur, but there seem to be several factors involved. Many autoimmune conditions, including spondyloarthritis, seem to be partly genetic.

Genes in the HLA (human leukocyte antigen) family are often involved in inflammatory arthritis. These genes encode a protein that your immune system uses to distinguish your own cells from harmful ones.

Certain variations in these genes may not work as well as others. When your immune system can’t properly distinguish between your cells and foreign ones, it may mistakenly attack your cells.

What triggers spondyloarthritis?

Genetics may play a part in spondyloarthritis, but they don’t cause it alone. While many people with spondyloarthritis carry the HLA-B27 gene, most people who carry it don’t get spondyloarthritis.

Something else must trigger the process. Researchers have many theories about what those triggers might be. Some of these include severe infections, environmental toxins, smoking and alcohol use.

One theory is that spondyloarthritis might be linked to dysbiosis in your gut microbiome. People with SpA tend to have less diversity in their gut, which makes it easier for harmful microbes to take over.

Gut dysbiosis can weaken your immune system by making you more susceptible to infections and triggering chronic inflammation in your gut. Your mix of gut microbiota is partly inherited at birth.

How is spondyloarthritis diagnosed?

Spondyloarthritis can be tricky to diagnose, especially if you don’t have a recognizable combination of symptoms. Some people only have joint pain and stiffness, which has many other possible causes.

A healthcare provider will start by asking you about your symptoms and check for any related symptoms you might not have mentioned. They’ll also ask about your health history and family health history.

They’ll physically examine your back or other joints and test your range of motion. They’ll take X-rays to look for evidence of arthritis or enthesitis, but evidence won’t always be visible in images.

They might order a blood test to check for signs of inflammation or autoimmune disease. They might also test you for the HLA-B27 gene. These tests can help to distinguish SpA from other diseases.

What treatment is available for spondyloarthritis (spondyloarthropathy)?

Treatment depends on your specific symptoms. Healthcare providers take a stepwise approach to treatment, starting with exercise and over-the-counter (OTC) nonsteroidal anti-inflammatory drugs (NSAIDs).

If these don’t do enough to manage your pain and inflammation, your provider might suggest:

• Periodic cortisone shots for more localized pain relief.
• Traditional or biologic DMARDs (disease-modifying anti-rheumatic drugs).

Some specific types of spondyloarthritis, like psoriatic arthritis and enteropathic arthritis, have other treatments that specifically relate to the underlying condition (psoriasis or inflammatory bowel disease).

How serious is spondyloarthritis?

When inflammatory arthritis is severe and lasts a long time, it can cause some serious complications. But they’re usually the type of complications that affect your quality of life rather than your life expectancy.

For example, you may lose mobility in your joints and may become more prone to bone fractures. But not everyone develops severe symptoms, and treatment can affect how the disease progresses.

How fast does spondyloarthritis progress?

How spondyloarthritis progresses is different from person to person. For some, it’s slow and easy to control with treatment. Others can develop ankylosing spondylitis with spinal fusion in just a few years.

How severe your inflammation is affects how quickly spondyloarthritis progresses. Being consistent with your treatment can help manage the inflammation and may prevent complications from developing.

How should I take care of myself while living with spondyloarthritis?

Regular exercise is crucial for anyone living with arthritis to maintain your mobility as much as possible. Many healthcare providers will tell you it’s more important and more effective than any medication.

If you aren’t sure what type of exercise would be best for you, ask your healthcare provider. Many providers also recommend formal physical therapy to address specific joints or problem areas.

A note from Cleveland Clinic

Spondyloarthritis is a family of related conditions that are both similar and different. While healthcare providers recognize them by their similarities, each type — and each person’s disease — is also unique.

For most people, spondyloarthritis is lifelong, but how much it affects your life can vary. Your healthcare provider will be your partner in managing your symptoms and predicting what you can personally expect.