Ankylosing Spondylitis Symptoms, Diagnosis and Treatment
Ankylosing spondylitis symptoms usually start with a dull ache and stiffness in the lower back or buttocks that builds slowly, often before age 45. Ankylosing spondylitis (AS) is a type of arthritis that causes inflammation in the spine [Source]. This guide explains the early signs, how AS is diagnosed and how it is treated.
Quick Answer: What Is Ankylosing Spondylitis?
- It is inflammatory arthritis of the spine. It mainly affects the spine and the sacroiliac (SI) joints, where the spine meets the pelvis.
- The key sign is inflammatory back pain. The pain is worse after rest, better with movement and comes with morning stiffness [Source].
- No single test confirms it. Doctors combine symptoms, an exam, blood tests and imaging [Source].
- There is no cure, but treatment helps. Exercise, physical therapy and anti-inflammatory medicines come first [Source].
What Is Ankylosing Spondylitis?
In ankylosing spondylitis, inflammation affects the joints and ligaments of the spine. Over time, it can cause stiffness. In severe cases, new bone forms and some of the vertebrae (spine bones) fuse together, which makes the spine rigid [Source]. AS can also affect the hips, knees, ankles, ribs and heels.
Doctors do not know exactly what causes AS. Genes and the environment both seem to play a role. A gene called HLA-B27 raises the risk [Source]. AS is more common in men, and early ankylosing spondylitis symptoms often begin between ages 15 and 30 [Source].
AS vs Axial Spondyloarthritis (axSpA)
AS belongs to a family of conditions called axial spondyloarthritis (axSpA) [Source]. When inflammation has caused changes that show on an X-ray, it is called AS, or radiographic axSpA. When the signs are there but the X-ray looks normal, it is called non-radiographic axSpA (nr-axSpA). MRI may still show inflammation. Some people with nr-axSpA go on to develop AS, but many do not.
Early Ankylosing Spondylitis Symptoms
Ankylosing spondylitis symptoms vary a lot. Some people have mild pain that comes and goes. Others have constant, severe pain. Symptoms can flare and then calm down [Source].
Inflammatory Back Pain
The most common symptom is pain and stiffness in the lower back or hips. The pain is often worse in the middle of the night or after sitting for a long time. Moving around and exercise usually help [Source]. If your back is stiffest when you wake up, read more about why your lower back hurts in the morning.
Buttock Pain and the SI Joints
AS often starts in the sacroiliac joints. People describe a dull ache deep in the lower back or buttocks [Source]. Many other problems also cause pain here. Learn about buttock pain and sacroiliac joint dysfunction.
Symptoms Beyond the Spine
AS can affect other parts of the body [Source]:
- Eyes: uveitis, an eye inflammation that causes eye pain, redness and vision changes
- Heels and tendons: pain where tendons attach to bone, such as the back of the heel
- Ribs: trouble taking a deep breath
- Skin and gut: psoriasis or inflammatory bowel disease (Crohn’s disease or ulcerative colitis)
- Whole body: fatigue, loss of appetite and weight loss
Ankylosing Spondylitis Symptoms in Women
Women get AS too, but their ankylosing spondylitis symptoms are often recognized later. In one large review, the average delay was 8.8 years for women and 6.5 years for men [Source]. It found no clear differences in symptoms between women and men to explain this gap.
Inflammatory vs Mechanical Back Pain
Most back pain is mechanical. It comes from strained muscles, discs or joints. Inflammatory back pain has a different pattern [Source]:
| Feature | Inflammatory back pain (possible AS) | Mechanical back pain |
|---|---|---|
| Age it starts | Usually before 45 | Any age |
| How it starts | Slowly, over weeks to months | Often after lifting, twisting or overuse |
| Rest | Does not help, may make it worse | Usually helps |
| Activity | Usually helps | Often makes it worse |
| Morning stiffness | 30 minutes or longer | Short, if any |
| How long it lasts | More than 3 months | Often improves within weeks |
This table is a guide, not a diagnosis. Some people have both types. If your pain has lasted for months, see why back pain may not be getting better.
How Ankylosing Spondylitis Is Diagnosed
No single test diagnoses AS [Source]. Your doctor will ask about possible ankylosing spondylitis symptoms and your family history. The exam checks how your spine, pelvis, heels and chest move, and whether your ribs expand fully when you breathe in.
Blood Tests: HLA-B27, CRP and ESR
Most people with AS carry the HLA-B27 gene, but many people with the gene never develop AS [Source]. A positive test is a clue, not a diagnosis. Blood tests such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) measure inflammation. They can be normal in some people with AS.
X-Ray vs MRI of the SI Joints
X-rays show joint changes, but you may have AS for years before changes appear. MRI can help find the disease earlier [Source]. Guidelines do not recommend routine repeat spine X-rays just to monitor the disease [Source].
Rheumatology Referral
If your symptoms and tests suggest AS, the next step is usually a rheumatologist. Rheumatologists specialize in arthritis and lead AS care [Source].
Ankylosing Spondylitis Treatment Options
There is no cure for AS, but treatment can relieve ankylosing spondylitis symptoms, help keep good posture and flexibility, and slow the disease [Source]. The best results come from combining exercise with medicine [Source].
Exercise and Physical Therapy
U.S. guidelines strongly recommend physical therapy for AS. They favor active, supervised exercise over passive treatments such as massage, ultrasound or heat [Source]. Stretching, strengthening and posture work help keep the spine moving. If you smoke, quitting matters. Smoking makes AS more severe and can blunt the effect of treatment [Source].
NSAIDs
Nonsteroidal anti-inflammatory drugs (NSAIDs), such as naproxen or ibuprofen, are the first-choice medicine for AS [Source]. No single NSAID is preferred [Source]. Your doctor will check that they are safe for your stomach, kidneys and heart.
Dr. Amit Sharma & our minimally invasive pain & spine team.
Biologics and JAK Inhibitors
If NSAIDs are not enough, a rheumatologist may prescribe a biologic, such as a TNF inhibitor or an IL-17 inhibitor [Source]. JAK inhibitors are another option when other treatments have not worked [Source]. Examples with FDA approval for active AS include adalimumab (Humira) [Source] and tofacitinib (Xeljanz), which is approved after a TNF inhibitor has not worked [Source]. These medicines affect the immune system and need regular monitoring. Long-term steroid pills are not recommended for AS [Source].
Where a Pain Specialist Can Help
Not every back pain in a person with AS comes from AS. A pain specialist can help tell inflammatory pain apart from mechanical problems, such as a disc or facet joint. When one SI joint stays inflamed despite NSAIDs, U.S. guidelines conditionally recommend a local steroid injection, based on very low-quality evidence [Source]. In selected cases, a sacroiliac joint injection may be an add-on to rheumatology care, not a replacement for it. Spinal manipulation should be avoided if the spine is fused or bones are thin [Source].
Red Flags: When to Get Urgent Care
A fused spine is stiff and can break even after a minor fall [Source]. Get care right away if you have AS and notice any of the following:
- New or different back or neck pain after a fall or minor injury: get urgent imaging, even if the fall seemed small.
- Eye pain, redness or blurry vision: see an eye doctor the same day.
- Leg weakness or numbness, or a new change in bladder or bowel control: go to the emergency room.
Read more about when back pain is an emergency.
Getting Evaluated at SpinePain Solutions
At SpinePain Solutions, Dr. Amit Sharma, Chief, Division of Pain Medicine at Good Samaritan University Hospital, evaluates people with long-lasting back and buttock pain, including possible ankylosing spondylitis symptoms. The visit includes your history, a careful exam and a review of your imaging. The goal is to sort out whether your pain looks inflammatory or mechanical and to explain your options. If AS is suspected, we help coordinate care with a rheumatologist, who manages AS medicines.
We see patients at our Bay Shore, Commack and Farmingdale offices. Call 631-310-0000 to schedule an evaluation.
Frequently Asked Questions
What are the first signs of ankylosing spondylitis?
The most common first sign is a dull ache and stiffness in the lower back or buttocks that starts slowly, often before age 45. It is usually worse after rest or in the morning and gets better with movement. It lasts for months, not days.
What is inflammatory back pain?
Inflammatory back pain is back pain caused by inflammation rather than strain or wear and tear. It usually starts before age 45, comes on slowly, lasts more than three months, improves with activity but not with rest, and causes morning stiffness that lasts 30 minutes or longer.
Does a positive HLA-B27 test mean I have ankylosing spondylitis?
No. Most people with ankylosing spondylitis carry the HLA-B27 gene, but many people who carry it never develop the disease. The test is one clue. Doctors combine it with your symptoms, exam, blood tests and imaging.
Can ankylosing spondylitis show up on an X-ray?
Yes, but often not at first. A person can have the disease for years before changes show on X-rays. An MRI can show inflammation in the sacroiliac joints earlier. When X-rays are normal but other signs are present, the condition may be called non-radiographic axial spondyloarthritis.
Is ankylosing spondylitis an autoimmune disease?
Not in the usual sense. The immune system drives the inflammation, but ankylosing spondylitis is usually described as an autoinflammatory disease. Unlike many autoimmune diseases, it is not typically linked to autoantibodies.
What kind of doctor treats ankylosing spondylitis?
A rheumatologist usually diagnoses ankylosing spondylitis and manages its medicines. Care often includes a team, such as a primary care doctor, a physical therapist and an eye doctor. A pain specialist can help sort out other causes of back pain and coordinate care.
Does exercise help ankylosing spondylitis?
Yes. Exercise and physical therapy are a core part of treatment. Guidelines recommend physical therapy and favor active, supervised exercise over passive treatments such as massage or heat. Staying active helps with pain, stiffness and posture.
Is ankylosing spondylitis different in women?
Ankylosing spondylitis is more common in men, but women get it too. Studies show women are often diagnosed later than men. Researchers have not found clear differences in symptoms that explain this delay, so women with ongoing back pain should ask about it.
Dr. Amit Sharma & our minimally invasive pain & spine team.
Medical References
- National Institute of Arthritis and Musculoskeletal and Skin Diseases. Ankylosing spondylitis: overview, symptoms and causes; diagnosis, treatment and steps to take. NIAMS; NIAMS treatment.
- MedlinePlus. Ankylosing spondylitis. National Library of Medicine. MedlinePlus.
- Spondylitis Association of America. Overview of spondyloarthritis. SAA.
- Ward MM, Deodhar A, Gensler LS, et al. 2019 Update of the American College of Rheumatology/Spondylitis Association of America/Spondyloarthritis Research and Treatment Network recommendations for the treatment of ankylosing spondylitis and nonradiographic axial spondyloarthritis. Arthritis Rheumatol. 2019;71(10):1599-1613. doi:10.1002/art.41042. PubMed; PMC full text.
- Ramiro S, Nikiphorou E, Sepriano A, et al. ASAS-EULAR recommendations for the management of axial spondyloarthritis: 2022 update. Ann Rheum Dis. 2023;82(1):19-34. doi:10.1136/ard-2022-223296. PubMed.
- Jovaní V, Blasco-Blasco M, Ruiz-Cantero MT, Pascual E. Understanding how the diagnostic delay of spondyloarthritis differs between women and men: a systematic review and metaanalysis. J Rheumatol. 2017;44(2):174-183. doi:10.3899/jrheum.160825. PubMed.
- Leone A, Marino M, Dell’Atti C, et al. Spinal fractures in patients with ankylosing spondylitis. Rheumatol Int. 2016;36(10):1335-1346. doi:10.1007/s00296-016-3524-1. PubMed.
- U.S. FDA-approved prescribing information (DailyMed): Humira (adalimumab); tofacitinib.
Related Reading
- Why Does My Lower Back Hurt in the Morning?
- Sacroiliac Joint Dysfunction and Pain
- Buttock Pain: Key Facts
- Back Pain: How Spine Specialists Diagnose the Real Cause
- When Is Back Pain an Emergency?
