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Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a type of inflammatory arthritis that affects the spine and the sacroiliac joints that attach the pelvis to the base of the spine. ‘Ankylosing’ means fusing and ‘spondylitis’ means inflammation of the spine. As well as being a form of inflammatory arthritis, AS is also an autoimmune disease, meaning the body’s own immune system attacks healthy tissue.

With AS inflammation, the immune attack targets the ligaments and tendons attached to bone in the joints of the spine. The bone erodes at these sites and the body tries to repair itself by forming new bone. The bones of the spine begin to fuse, or grow together, causing the spine to become stiff, inflexible and painful. Even though new bone forms, the original bone in the spine can become thin, increasing the risk of spinal fractures.

Ankylosing spondylitis is the most common form of a group of inflammatory arthritis called spondyloarthritis. These diseases are related clinically and genetically, but have distinct features from one another. They are grouped into two broad categories: axial spondyloarthritis – diseases affecting the spine, such as ankylosing spondylitis, and peripheral spondyloarthritis – diseases that affect other parts of the body such as the fingers, arm and leg joints. In some cases, these axial and peripheral symptoms can overlap. Additional symptoms outside the joints can include inflammation in the skin, the gastrointestinal tract, and the eyes.

Spondyloarthritis diseases are different from other inflammatory forms of arthritis like rheumatoid arthritis in the joints that are affected, and the age of onset. People with spondyloarthritis do not have high titre (concentration) rheumatoid factor antibodies in their blood: they are known as seronegative, whereas people with rheumatoid arthritis can have high or low titre rheumatoid factor antibodies. Seronegative rheumatoid arthritis (with negative rheumatoid factor) is possible and should not be confused with spondyloarthritis. At the same time, having low titre rheumatoid factor antibodies does not exclude spondyloarthritis.

To learn more about your patient journey with ankylosing spondylitis, click here.


What are early signs of ankylosing spondylitis?

Typically, the first symptoms of ankylosing spondylitis start in late adolescence or early adulthood between the ages of 15 and 30. Inflammation usually starts at the base of the spine, often in the sacroiliac joints around the pelvis. It can spread upwards to other parts of the spine, and in the most severe cases can involve the entire spine.

In addition to the spine, AS can cause pain and stiffness in peripheral joints such as the hips and shoulders. The stiffness is due to inflammation in the joints – arthritis – and of the tendons surrounding the joints – called enthesitis. Some common spots for enthesitis are the back of the heels (Achilles tendonitis), the bottoms of the feet (plantar fasciitis), the outside of the hips (trochanteric bursitis), and along the breastbone (costochondritis).

When the immune system lacks the normal checks and balances, it can attack parts of the body other than the joints and tendons. In AS, this attack may also cause inflammation in the eye, a condition called uveitis or iritis.

How is ankylosing spondylitis diagnosed?

Ankylosing spondylitis is difficult to diagnose; it is a highly variable disease with a wide range of symptoms. Some individuals may only experience episodes of mild back pain, while others will have severe chronic pain accompanied by stiffness in the spine affecting their posture and daily activities. Weight loss, fatigue and feeling feverish or experiencing night sweats are symptoms that can occur, particularly in the early stages.

The most universal symptom; however, is chronic low back pain that seems to come (“flare”) and go for no apparent reason. The pain and stiffness are generally worse in the morning when rising from bed, and improve with stretching and exercise as the day progresses. Similarly, people with AS tend to feel better after exercise and worse after rest. AS back pain generally persists for weeks or months, rather than hours or days.

An estimated 300,000 Canadians have AS, while about 6.5 million Canadians experience chronic mechanical back pain. Separating the two is important since treatments for these forms of back pain are very different.

Early, accurate diagnosis of AS is important because the damage it causes is difficult if not impossible to reverse; however, early detection and treatment can prevent lasting damage to the spine. Researchers are working to develop a reliable blood test that will assist doctors in detection.

What are the risk factors for ankylosing spondylitis?

As many as 90 per cent of people who develop AS have a gene called HLA-B27. However, not everyone with AS have this gene – so even if you test negative for the gene, you could still have AS. On the contrary, if you do have this gene, however, it does not necessarily mean you will develop AS; most people (95%) with the gene do not develop the disease. Research is being conducted into other factors that may cause AS but currently there is nothing conclusive to report.

How common is ankylosing spondylitis?

The number of people with a confirmed diagnosis is likely lower than the actual number due to the difficulty of diagnosis, however, estimates suggest as many as one per cent of the Canadian adult population (300,000) lives with AS.

Why is treatment for ankylosing spondylitis so important?

Early treatment of ankylosing spondylitis is important because a combination of exercise and medication can reduce severe damage to the spine by controlling the inflammation, keeping the spine flexible and the joints mobile. Although there is no cure for AS, early diagnosis and treatment allows most people with AS to lead active and productive lives.


An ankylosing spondylitis diagnosis is typically made or confirmed by a rheumatologist. They will work with you to develop a disease treatment plan, in an effort to get the inflammation under control and slow or stop the progression of the disease. For a person diagnosed with AS, the rheumatologist is the leader of your healthcare team


Arthritis medications are designed to control disease, slow its progression, and to help manage pain. There is a wide range of options – with new ones coming on the horizon – so understanding all possible treatments is not easy.

These medications can be very complex, so you are encouraged to ask for in-depth explanations from your health care team – including pharmacists, who are an excellent source of information.

To explore this area of treatment, the Arthritis Society has developed a comprehensive expert guide that delivers detailed information on medications used to treat arthritis.

EXPLORE: Arthritis Medications – A Reference Guide

The optimal treatment is what is best in each individual case – so speak with your doctor and/or pharmacist about what kind of medications are most appropriate for you.


Those with severe, advanced AS may require surgery for badly damaged joints. Surgery usually involves replacing a joint with an artificial joint. This is called a total joint replacement, and is most commonly used for the end stage of damage to the hip or knee joints. Benefits include less pain, better movement and restored function. Spinal surgery is complex and is only used in those with severe deformity.

For more information on hip, knee or ankle replacements, please visit our comprehensive section on surgery


A physiotherapist (PT) can develop an individualized program designed to help you increase your strength, flexibility, range-of-motion, and general mobility and exercise tolerance through a wide variety of therapeutic treatments and strategies. These include exercise prescription, physical interventions, and relaxation, in addition to advising you on other techniques for reducing pain and increasing your overall quality of life.

PTs can also refer you to other health professionals and community services for further measures that will help you adapt to your changing circumstances.

An occupational therapist (OT) trained in arthritis management can analyze everything you do in a day and develop a program to help you protect your joints and minimize fatigue. These healthcare professions have advanced training from a university and are registered to practice by their provincial/territorial association.

If necessary, your OT can help you redesign your home or workplace to make it easier for you to work or simply get around. They can also make or recommend a number of different splints, braces, orthopedic shoes and other aids that can help reduce your pain and increase your mobility and functionality. Their goal is to prepare you, using assistive devices and adaptive strategies, to reclaim as much of your former life as possible.


In addition to following your treatment plan, there is a lot you can do yourself to help decrease your pain and increase your movement. Physiotherapy, occupational therapy, regular exercise and relaxation techniques are very important parts of your overall treatment plan. Although you can undertake many of these activities on your own, it is important to assemble a healthcare team who can help oversee and direct your self-management efforts. Learning as much as you can about the disease is also important to help you make informed decisions about treatment and lifestyle, and maximize your quality of life.

Watch your eyes

About 30 per cent of people with AS will develop iritis (eye inflammation). This is a rapid onset of inflammation in the front of the eyeball. The eye may feel irritated and there may be pain in the eye or surrounding area. You could experience headaches, blurred vision or sensitivity to light. Iritis usually happens in one eye only. If you think you may have iritis, you should see an ophthalmologist (eye specialist) as soon as possible. Prescription eye drops (steroids) can stop the attack and prevent potential loss of vision.

Take care of your bones

People with AS may develop a fused spine. Often the fused spine can become brittle and prone to easy breaks (fractures). Generally, people with AS should take calcium and vitamin D supplements. Avoid activities involving forward bending or heavy lifting. Fractures are more common in AS when the spine is fused. Fusion of the spinal joints in AS usually occurs in the late stages of the disease and may limit movement; however, fusion can sometimes improve feelings of pain and stiffness.


For people with AS, good posture is particularly important. This means keeping the spine as straight as possible. Common activities like using the computer, a mobile device or watching television can contribute to poor posture. Exercises to improve posture, strengthen core muscles and improve lung capacity may be appropriate for some patients.

Physical activity

Physical activity is any activity that uses your muscles and increases your heart rate. Physical activity strengthens the muscles and connective tissues around your joints, helping support joints that have been weakened by arthritis. Participating in a properly designed exercise program is a great way to help alleviate the discomfort caused by arthritis. So are all those activities that you do as a part of everyday life – such as vacuuming the house, walking to work, even gardening. These kinds of activities can be very beneficial for your joints, and can help you maintain and improve your mobility.


Exercise is physical activity that involves heavier, repetitive exertion, and is designed to improve or maintain physical fitness. Lifting weights, running on a treadmill, taking a yoga class – these are the kinds of planned motions that we do specifically to improve our flexibility, strength or endurance. Being physically active can reduce pain and fatigue, improve mobility and overall fitness, and improve your state of mind by allowing you to actively participate in your own treatment.

There are different types of exercises you can do to decrease pain and stiffness:

  • Flexibility exercises, including stretches and range of motion exercises, improve flexibility and can reduce pain and stiffness and help keep your joints moving. Range of motion refers to the amount your joints can move in certain directions. Stretches elongate muscles and are best done when muscles are already warmed up. Ideally, you should complete range of motion exercises every day even on days when your joints are sore. For some ideas about stretches, check out our “Simple Stretches” video. 
  • Strengthening exercises maintain or increase muscle tone and protect your joints. These exercises include weight training done with “free” weights, your own body weight or weight machines.
  • Endurance exercises strengthen your heart, give you energy, control your weight and help improve your overall health. These include walking, swimming and cycling including stationary bikes. It is best to avoid high-impact exercises like contact sports.

For more information about arthritis, physical activity and exercise, visit our Exercise & Motion page. 

Protect your joints

While it’s important to keep your joints moving, it’s also important to avoid situations that put excessive stress or strain on your joints, as that can increase your risk of injury and make your joints deteriorate faster. Avoiding joint stress will also lead to less pain and help your joints work better, longer.

Techniques to protect your joints include:

  • Pace yourself: alternate heavy or repeated tasks with lighter tasks. Taking a break reduces stress on painful joints and conserves energy by allowing weakened muscles to rest.
  • Keep joints aligned: Positioning joints wisely promotes proper alignment and decreases excess stress. For example, squatting and kneeling may put extra stress on your hips or knees. When lifting or carrying heavy items, keep items at waist height and avoid carrying them up and down stairs.
  • See a therapist: Talking to your doctor about seeing a physiotherapist who can customize your exercise program, or an occupational therapist who can advise you on assistive devices and adaptations for your home or workplace.
  • Use assistive devices: Using appropriate tools and devices not only makes tasks easier, it helps to conserve your energy. Raise seat levels to decrease stress on hip and knee joints. Use a reacher to pick up items from the ground. Use a cane or walker to decrease stress on hip and knee joints.

For more information about protecting your joints, visit our Daily Living online module

Heat & Cold

Taking a warm shower and using warm packs are great ways to help reduce pain and stiffness. Always use a protective barrier, such as a towel, between the warm pack and the skin. Heat is ideal for:

  • Relieving pain
  • Relieving muscle spasms and tightness
  • Enhancing range of motion

IMPORTANT: Do not use heat on an already inflamed joint, as it can make symptoms worse.

Using a commercial cold pack or a homemade one (from crushed ice, ice cubes or a bag of frozen vegetables) can be helpful to help provide short-term relief from inflammation. Always use a protective barrier, such as a towel, between the cold pack and the skin. Cold is ideal for:

  • Swelling
  • Decreasing pain
  • Constricting blood flow to an inflamed joint

For more information about using heat or cold, visit our Pain Management page.

Eating well

There is no conclusive evidence to suggest that what you eat can make arthritis either better or worse. However, being overweight can put excess strain on your joints, including the spine. To work normally, your body needs food to supply energy, vitamins and minerals. Healthy eating will help you manage your weight and give you the energy to complete your daily activities, as well as promote a strong immune system, and bone and tissue health.

Three ways to improve your nutrition include:

  • Reduce fat intake: A healthy diet should include a small amount of unsaturated fats and limited amounts of saturated and trans fat. Choosing the right amount and types of fats help you achieve and maintain a healthy body weight.
  • Reduce sugar intake: Sugar contains “empty” calories and has no nutritional value. This includes syrup as well as white, brown, cane and raw sugar. Limit or avoid adding sugar to drinks and cereals. Although artificial sweeteners contain fewer calories, it is best to get used to food being less sweet. Use dried, unsweetened fruit like raisins, cherries or dates to sweeten cereals since they provide vitamins, minerals and fibre.
  • Eat more vegetables and fruit: Vegetables and fruit should make up the largest component of your diet. Keep in mind that the sweetest fruits have high sugar content so best not to overdo it. Try to have at least one vegetable or fruit at every meal and while snacking. Besides being an excellent source of energy, vegetables and fruit boost your fibre intake, which helps with digestion and weight management. They are also loaded with antioxidants, which help boost the immune system and may help maintain healthy cartilage.

For more information about eating well, visit our Arthritis and Nutrition page. 

Relaxation and coping skills

Developing good relaxation and coping skills can help you maintain balance in your life, giving you a greater feeling of control over your arthritis and a more positive outlook. Relaxing the muscles around a sore joint reduces pain. There are many ways to relax. Try deep breathing exercises. Listen to music or relaxation tapes. Imagine or visualize a pleasant and restful activity, such as lying on a beach.

For more information about relaxation and coping skills, visit our Pain Management page. 

Complementary therapies

People with a chronic disease like arthritis may decide to try complementary or alternative therapies to help them manage the symptoms of their condition. Complementary and alternative therapies are treatments that fall outside the scope of traditional North American medicine. Examples include homeopathy, acupuncture and meditation.

Before you try any of these treatments, always inform your healthcare provider of any complementary and alternative therapies you are taking, receiving or would like to try. Your healthcare provider can offer valuable advice about these treatments, especially how they may affect other medications and treatments.

For more information, visit our Complementary and Alternative Therapies page. 

What Now

Living well with arthritis

There is a lot you can do to take control and actively manage your arthritis. Below we have listed a few resources to help you learn more about actively managing your arthritis to live better.


To find health & wellness advice, self-management tips, inspirational stories, and much more.

Explore Flourish

Online Learning

Our online courses are jam-packed with helpful tips and information.  Each course is devoted to a specific issue or symptom linked to arthritis.

Discover Arthritis Courses

Workshops and Webinars

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Navigating Through Arthritis

Learn about information and services available.

Navigate through arthritis


This information was last updated July 2019, with expert advice from:

Dr. Nigil Haroon, MD, PhD
Co-Director Spondylitis Program, University Health Network
Scientist, Krembil Research Institute

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