Ankylosing spondylitis (AS) is a type of arthritis that inflames the joints (vertebrae) in the spine. The most commonly affected part of the spine in the sacroiliac (SI) joint. This is the joint where the spine connects with the pelvis. The condition affects other joints in the body in some cases including the ribs, shoulders, knees, hips, and feet. The condition causes pain, stiffness, and discomfort along the length of the spine. Rarely, AS involves the bowel, eyes, lungs, and heart. Many people who have AS have mild, intermittent pain. Some have constant, severe pain. Some people experience a loss of flexibility in the spine due to AS.
Spondylitis means inflammation of the spine. Ankylosis is when bones fuse together. When vertebrae become inflamed and fuse together, the condition is called ankylosing spondylitis. AS is a type of spondyloarthropathy. Spondyloarthropathies are chronic, long-term joint diseases. The spondyloarthropathies include AS, psoriatic arthritis, reactive arthritis, and enteropathic arthritis, a type of arthritis that sometimes occurs in people who have inflammatory bowel disease. The most common symptom of spondyloarthropathy is lower back pain. Spondyloarthropathies have a tendency to run in families. Another name for spondyloarthropathies is spondyloarthritis. This refers to inflammatory conditions that involve the joints and the entheses (areas were tendons and ligaments attach to bones). Spondarthropathies may mimic rheumatoid arthritis in a variety of ways. However, spondarthropathies do not feature rheumatoid factor, antibodies that are present in many people who have rheumatoid arthritis.
Spondyloarthropathies are grouped into two main classes. Axial spondyloarthritis is inflammation of the spine and sacroiliac joints. Peripheral spondyloarthropathritis is inflammation that affects the peripheral joints.
Non-radiographic axial spondyloarthritis (nr-AxSpA) is a different kind of inflammatory arthritis where there's no visible damage on X-rays.
Other less common names for ankylosing spondylitis are Marie Strümpell disease and Bechterew disease.
Most people develop AS as teens or young adults. The majority of people with the condition develop it before the age of 30. Approximately twice as many men are affected by AS as women. Most people who have AS have a gene called HLA-B27. On the other hand, people with the gene do not always get AS. Other genes, including ERAP1 and IL23R, confer a genetic risk for AS.
Low back pain and stiffness are some of the most common early symptoms of AS. They often develop gradually over weeks or months. Most people with AS describe the pain as diffuse and dull. Pain and stiffness tend to be worse at night, after being sedentary, and in the mornings. Early symptoms include loss of appetite, fever, and discomfort. Light exercise tends to make pain feel better. Rest makes pain feel worse. Eventually the pain may spread up the length of the spine and into the neck. Shoulder blades, ribs, thighs, hips, and heels may eventually be affected.
An enthesopathy is a disorder that affects locations where ligaments and tendons attach to bones. Enthesitis is inflammation of these areas that occurs with AS and causes pain and swelling. Commonly affected areas include the heels, pelvis, sacroiliac joints, and the front of the shinbone. When ribs are affected, a patient may have trouble breathing because it hurts to expand the chest. If enthesitis occurs in the feet, it may make it difficult to walk. The Achilles tendon in the back of the heel is one location that may be affected. Another area that may be affected is the plantar fascia at the base of the heel.
The effects of ankylosing spondylitis go beyond the spine. AS may include joint involvement of the knees, shoulders, and hips. AS may degrade bone leading to osteoporosis. Fatigue is a common in ankylosing spondylitis. Pain and discomfort can interfere with sleep, leading to fatigue. Inflammatory molecules, or cytokines, released in AS make people tired. Cytokines may also lead to anemia. If inflammation impacts the gastrointestinal tract, colitis may occur and lead to weight loss. AS may also cause inflammation that affects the heart, lungs, and eyes. Approximately 33% to 40% of people with AS experience eye inflammation, iritis or anterior uveitis. Rarely, inflammation of the aorta (aortitis) may occur.
The prognosis of ankylosing spondylitis varies. Some people have minor pain and few limitations due to their disease. Some people experience more severe pain and other effects. Almost everyone who has AS experiences periods of exacerbation of symptoms and remissions. People who have other health problems, physically demanding jobs, and those who smoke are more limited by AS. . People with severe disease may experience fusing of vertebrae and stiffening of the spine, which may severely limit function. When completely fused vertebrae are visible on an X-ray it is known as bamboo spine. When vertebrae are fused they are said to be ankylosed. Bony outgrowths (syndesmophytes) may be visible along the spine in areas of inflammation of the ligaments that attach contiguous vertebrae.
Symptoms of ankylosing spondylitis often tend to develop slowly, over the course of weeks or months. Sometimes, AS emerges more quickly. Early diagnosis and treatment can help prevent damage and preserve function. If you experience lower back pain or pain in the hips or buttocks for more than a few months, it's a good idea to see the doctor for an evaluation. Inflammation of the SI joints, sacroiliitis, causes pain in the lower back and upper buttocks. Other telltale signs of potential AS are back pain that feels worse in the morning. Pain that is worse with rest, but is better with exercise may also indicated AS. If you are experiencing red, painful eyes, blurry vision, or sensitivity to light, see your ophthalmologist.
Diagnosis of AS may take some time. The doctor will evaluate you, perform a physical exam, and take your medical history. The doctor may order blood tests to check for inflammatory markers and the HLA-B27 gene. The doctor may order imaging tests like X-rays to view the spine and sacroiliac joint or an MRI to view soft tissues and bones. Imaging tests are also useful after diagnosis to monitor the progression of the disease. Inflammatory damage due to spondylitis may be visible on these imaging studies. A rheumatologist is a specialist that diagnoses arthritis and related conditions, including ankylosing spondylitis.
AS is a lifelong condition that cannot be cured. Treatment can provide relieve and help prevent severe complications from spondylitis. Early diagnosis and treatment provide the best opportunity for the most favorable outcome. Ankylosing spondylitis is treated with a variety of medications and lifestyle changes. Exercise, good posture, and adequate sleep can help. Many find physical therapy to be helpful. Gentle stretches, hot and cold packs, and warm baths can ease pain.
A variety of medications are used in the treatment of AS. Nonsteroidal anti-inflammatory drugs (NSAIDs) alleviate swelling, pain, and stiffness by blocking prostaglandins. This class includes naproxen, aspirin, and ibuprofen. Corticosteroids are medications that alleviate inflammation. They may be taken orally or injected. Doctors may inject corticosteroids directly into the sacroiliac joint, knee joint, or hip joint. Disease-modifying antirheumatic drugs (DMARDs) block inflammation and change the way the immune system works to prevent joint destruction. Common DMARDs used to treat AS include methotrexate and sulfasalazine. Biologic medications are targeted agents that inhibit inflammation that drives disease processes like AS. Etanercept, infliximab, adalimumab, certolizumab, secukinumab, and golimumab are biologics for the treatment of AS. They are either injected or infused.
Eating right and being physically active are helpful to relieve symptoms of AS. Some find that avoiding starch foods (potatoes, bread, and rice) is helpful. Make sure your diet provides you with adequate protein. Eat lots of fruit and vegetables. Perform strengthening exercises with weights to build muscles. Strong muscles support joints better. Do range-of-motion exercises to increase flexibility and improve movement. These exercises can reduce joint stiffness. Exercises that involve stretching and extending the spine may help prevent long-term disability. If exercising is painful for you, try exercising in a pool with warm water.
Spondylitis can affect your posture. You can help your condition by maintaining good posture. Check how you stand in the mirror. Stand sideways and glance at yourself. Do you lean forward or backward? Do you slouch? Straighten yourself up and notice the feeling in your muscles when you stand up straight. Straighten your posture whenever you notice that you are not standing up straight. Maintaining good posture may help prevent some of the potential complications associated with AS. Have an ergonomic set up at work to keep strain off your spine.
When you have AS, it's important to keep your spine straight and supported while you sleep. Choose a firm mattress that is not too hard. Sleeping in a non-bent position is best. Avoid using lots of pillows that may overextend your spine and neck. It can be helpful to sleep on your belly without a pillow. If you sleep on your back, use no pillow, a thin pillow, or even a rolled up towel to support your head and neck. Do not curl your legs up. It is best to keep your legs stretched out straight. Many people who have AS report waking up at night and needing to walk around to get some relief. Tell your doctor if AS interferes with your ability to fall asleep or stay asleep.
One of the big dangers with AS is a loss of flexibility. This, in turn, affects body posture and the function of the spine. If loss of spinal mobility happens early on in the course of the illness, AS has a worse prognosis. Physical therapy is a useful way to preserve spinal flexibility and fitness. Regular physical therapy can help prevent postural deformities, increase range of motion, and build muscle strength. All of these help decrease pain. Physical therapists also provide patient education and coaching about maintaining good posture and the best positions to sleep in.
Both heat and cold may help relieve AS symptoms. When do you use heat and when do you use cold? Heat is good for stiff joints and tense muscles. If you wake up in the morning and feel stiff, take a warm bath or a shower to loosen tense joints and tissues. Gentle stretching can help, too. Apply a heating pad or an electric blanket to stiff areas. Cold is best used for inflammation, local pain, and swelling. Take a break between icing so you do not damage tissues.
Sitting for long periods of time is not good for anyone, but it's especially bad for people with AS. Sitting in an awkward position increases stress on your back, neck, legs, and arms. This can add pressure to discs in the spine and back muscles. Slouching may lead to strained discs and overstretching ligaments in the back. Ensure you have a good ergonomic set up at work. Sit with your feet flat on the floor. Maintain a 90-degree bend in your elbows. Sit with your buttocks touching the back of your chair. Your chair should have adequate lumbar support to help prevent slouching and strain on your back. Raise your computer screen so your eyes can see the middle of screen when looking straight ahead. Take frequent breaks. An adjustable workstation that allows you to sit or stand when you work can be a good option. Seek help from an occupational therapist if you need advice about how to set up your work space so that it is safe for you. He or she may be able to recommend certain devices to make it easier for you to do your job.
Many people with AS do not have a problem driving. If AS affects your range of motion, it might be hard to turn your head when backing up or looking side to side while driving. If that is the case, there are special mirrors that can help you see without having to turn your head so much. Make sure your headrest is at the proper height for you. It should be at least level with the tops of your ears. On long car trips, pull over and take breaks so you can get out of the car and walk around for several minutes.
Pain and stiffness with AS may make it more difficult to have sex. Medications may help relieve pain. Chronic inflammation of the SI joints or lumbar spine can make sex painful. Try different positions that are more comfortable and place less strain on your back. It's important for you to communicate with your partner openly. Let your doctor know if AS symptoms interfere with sexual function. He or she may be able to prescribe medications to help.
IMAGES PROVIDED BY:
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- Arthritis Foundation: “Using Heat and Cold for Pain Relief.”
- Arthritis Research UK: “Driving and Ankylosing Spondylitis (AS),” “Sex, Pregnancy, Children and Ankylosing Spondylitis (AS).”
- National Institute of Arthritis and Musculoskeletal and Skin Diseases: “Questions and Answers about Ankylosing Spondylitis,” “What Is Ankylosing Spondylitis?”
- Spondylitis Association of America: “Exercise & Posture,” “How Is a Person Affected?” “Most Common Symptoms,” “Physical Therapy and Surgery.”
- Therapeutic Advances in Musculoskeletal Disease: “Axial Spondyloarthritis: Is There Treatment of Choice?”
- UCLA Spine Center: “Ergonomics for Prolonged Sitting.”