Ankylosing Spondylitis Overview

Ankylosing spondylitis (AS) is a type of arthritis that primarily affects the back (spine). In ankylosing spondylitis, the joints and ligaments that normally let the back move become inflamed. This produces pain and stiffness. Other joints, such as the knee and shoulder, may also become inflamed. This form of arthritis most commonly occurs in young men between the ages of 15 and 30.

Ankylosing spondylitis can also occur in women and children, although their symptoms may vary from the typical profile presented by a young adult male. More than 200,000 Americans have ankylosing spondylitis and almost everyone with this type of arthritis carries a specific gene called HLA-B27.

Ankylosing spondylitis (pronounced ankle-low-zing spond-ill-eye-tis) can be somewhat difficult to diagnose as low back pain is a common problem and initial x-ray studies are often normal.

Early diagnosis is important, and people who suffer from the joint pain associated with this disease need a comprehensive treatment plan that helps manage the pain and maintains or extends their range of motion. If left untreated, ankylosing spondylitis can lead to deformities and chronic pain. New, effective medication is now available and can be discussed as a treatment option with your treating rheumatologist.

Ankylosing Spondylitis is a Form of Arthritis

Ankylosing spondylitis is a type of arthritis that typically afflicts the joints in the spine and results in fusion of sections of the spine. The term “ankylosing” means “stiff” or “rigid”. “Spondyl” refers to the spine and the means of inflammation. As a result of this inflammation of the spine, the vertebrae may grow together (fuse), causing the spine to become rigid and inflexible.

The fusion is a reaction to inflammation of ligaments or tendons where they attach to bone. The bone then erodes at the site of the attachment (enthesopathy) but as the inflammation subsides, new bone grows in its place as part of the healing process. Because the new bone is rigid, and not elastic like the tissue or ligaments, spine movement is compromised.

The joint inflammation can affect different segments of the spine, causing more bone to form and fusing the individual vertebrae and joints in the spine. If the spine fuses together in a hunched forward position, internal organs such as the heart and lungs can also be affected. In severe, advanced cases of ankylosing spondylitis there is a complete fusion of the bones of the spine, turning the spinal column into one long bone instead of a series of joints that provide a high degree of movement and flexibility in all directions.

Fortunately, for most ankylosing spondylitis patients, the disease only causes partial fusion in the spine and does not progress to the extent where their posture and form will be visibly affected. Many patients may find that the disease stops progressing and stabilizes at a certain level, with or without undergoing a specific ankylosing spondylitis treatment regimen. A minority of patients have reported that symptoms actually become less severe with age. However, limited flexibility in just one or a few segments of the spine can still lead to acute joint pain and restricted movement.

Ankylosing Spondylitis Characteristics

Unfortunately the origins of ankylosing spondylitis are not well understood, but genes and heredity play an important role. A gene called HLA-B27 is found in more than 90% of people with ankylosing spondylitis.

Some researchers have also proposed that certain types of bacterial infection may trigger the development of ankylosing spondylitis in individuals who are genetically predisposed. However, despite encouraging evidence, this theory has proven difficult to confirm.

This form of arthritis is much more prevalent in males, and generally is diagnosed before they reach the age of 30.

Ankylosing spondylitis often occurs in the teens or early 20s
This form of arthritis generally affects young adults, commonly beginning before patients are 35 years old. The average age at diagnosis is 24, although children – as well as older patients – have also been diagnosed with varying stages of the disease.

Ankylosing spondylitis occurs more often in males
Ankylosing spondylitis is diagnosed more often in men, who also tend to have more severe symptoms. Some professionals believe that the disease may actually be equally prevalent in both genders but diagnosis is often overlooked or missed in women because they tend to have pain in peripheral joints, such as the neck or hips, as well as the back.

Ankylosing spondylitis is a chronic disease that varies greatly in severity across both age and gender.
Many cases are characterized by acute painful episodes known as “flares” that are followed by periods of relative relief. More serious cases can have a rapid onset of severe pain and stiffness all over the body that does not ease for long periods.

Patients with crippling joint pain caused by severe cases of ankylosing spondylitis tend to have several distinctive characteristics:

• A ‘curled forward’ posture – the chin-to-chest stance – which results in a persistent downward gaze
• Brittle bones in the spine that are prone to fractures
• Significantly limited mobility and movement, such that the patient is permanently disabled

Of the disease progresses from the low back all the way up the spinal column, patients are at risk of developing significant complications that can increase the pain and disability already experienced. Potential complications include:

• Cauda Equina syndrome, which can cause pervasive extremity numbness, weakness and bowel or bladder dysfunction
• Spondylodiscitis, an inflammation of the intervertebral disc caused by the hardening of the fibrous tissue that encompasses the disc
• Limited chest expansion, which may impact the ability to breathe freely

These complications are quite rare and are generally only seen in the most severe cases of ankylosing spondylitis.

Ankylosing Spondylitis Symptoms

There is a broad range of symptoms caused by ankylosing spondylitis. Although symptoms can vary widely, the first symptoms typically noted by patients include:

• Sacroiliitis, an inflammation of the sacroiliac joint where the spine attaches to the pelvis. This causes pain in the buttocks that can radiate down the thigh, but does not go past the knee.
• Gradual onset of lower back pain, buttock pain or hip pain with stiffness over a period of weeks or months
• Unlike back pain from other causes, pain from this type of arthritis is worse during periods of rest or inactivity. Patients may wake up from sleep with severe pain.
• Early morning stiffness and limited movement which improve with a warm shower or light exercise
• Tenderness over the inflammation site (most often over the first joint of the lowest part of the spine, the sacroiliac joint)
• Weight loss and/or loss of appetite
• Unexplained fatigue
• Fever and night sweats

Changes in the Location of Joint Pain

The initial pain caused by ankylosing spondylitis is not always located in the lower back, however. For example, females have reported experiencing pain in the neck more frequently than males. Children almost never experience pain in the back, but rather in their heels or knees.

In addition to lower back involvement, other symptoms include:

• Joint pain. 50% of patients with ankylosing spondylitis will develop inflammation of joints in the arms and legs. Inflammation that causes knee pain, ankle pain or shoulder pain is most common.
• Enthesitis. Inflammation of the spots where ligaments and muscles attach to bones is a common source of pain, stiffness, and restriction of the joints. In addition to the spine, enthesitis affects the plantar fascia of the foot and the Achilles tendon.
• Eye pain. Eye inflammation (iritis) occurs in 25% of ankylosing spondylitis patients. Iritis causes redness and eye pain and can be a serious condition. Iritis requires immediate attention by an ophthalmologist.
• Respiratory difficulty. The rib cage may fuse, which can limit normal expansion of the lungs and cause breathing difficulties.
• Cardiac problems. Rarely, ankylosing spondylitis can affect the heart.
• Shoulder and knee stiffness. As stiffness in the lower back limits the patient’s movement, flexibility in these smaller joints also decreases.

It can be quite a challenge to diagnose ankylosing spondylitis. That is because a patient can feel the symptoms of the disease years before changes in the spine anatomy, such as the growth of bones and the fusing of joints, can be seen on X-rays. Early diagnosis is important, however, as patients can better maintain flexibility and movement if treatment is started before the disease and associated joint pain progress too far.

Patients can expect doctors to use a three-part protocol to confirm a diagnosis of ankylosing spondylitis. This typically involves reviewing a patient’s medical history, performing a physical exam, and reviewing the results of diagnostic tests, including x-rays, CAT scans (CT scans), and magnetic resonance images, as well as blood tests.

Ankylosing Spondylitis Medical History

Patients will be asked to describe when and how their joint pain or other symptoms first occurred, if they have changed in severity or location, and if any treatment has provided pain relief. The presence or history of related conditions including uveitis (inflammation of the eye), gastrointestinal infections (Crohn’s disease, ulcerative colitis), and frequent fatigue are also important factors in an accurate diagnosis.

In addition, because this form of arthritis does have a genetic component, information about any family members who suffer from the disease or symptoms similar to the patient’s are also considered.

Ankylosing Spondylitis Physical Exam

A patient’s physician, typically a general practitioner, will first look at the patient’s posture to see if the lumbar spine (lower back) is losing its normal curve and beginning to flatten out. An examination of the whole spine can identify whether the inflammation has moved up from the lumbar region. Because symptoms can be different between patients (and notably so for women and children), it is important that other joints, particularly the hips and ankles, be examined also. The physician may also assess flexibility and the range of motion of specific joints to quantify the impact of the patient’s symptoms.

If classic symptoms of ankylosing spondylitis are present, most general physicians will refer patients to a rheumatologist. A rheumatologist is trained to recognize the symptoms of ankylosing spondylitis and will most likely conduct more extensive testing.

Ankylosing Spondylitis Diagnostic Tests

There are two categories of diagnostic tests used to identify ankylosing spondylitis: imaging scans (e.g., x-rays, magnetic resonance images) that capture a picture of the spine and affected joints, and blood tests that identify certain markers of ankylosing spondylitis.

Imaging Scans
In the early disease process, plain x-rays may be read as normal. To diagnose ankylosing spondylitis, the sacroiliac joints (SI joints) at the back of the pelvis must be affected. X-ray evidence of sacroiliitis is one of the most telling signs of this condition. More accurate and earlier diagnosis can be done using magnetic resonance imaging (MRI scans) and or CAT scans (CT scans).

Blood Tests
An elevated CRP and/or WESR (sedimentation rate) can be found in any inflammatory state, including ankylosing spondylitis. As mentioned previously in this article, 90% of people with ankylosing spondylitis test positive for the HLA B27 gene. Having this gene, however, does not necessarily mean that ankylosing spondylitis is present or that it will develop. 8% of healthy Caucasians and 2% of health African-Americans carry this gene. In fact, a healthy person who carries this gene and has no relatives with ankylosing spondylitis has only a 2% chance of getting this form of arthritis.

Some doctors may also run blood tests to rule out possible causes of similar symptoms, including fibromyalgia, spinal or bone tumors, infection, pelvic inflammatory disease, metabolic bone disease, diffuse idiopathic skeletal hyperostosis (DISH), and prolapsed intervertebral disc.

There is no cure for ankylosing spondylitis but there are several ways of managing the symptoms so that the progression of the disease and the joint pain are controlled and the spinal deformity minimized.

It should be noted that—unlike many other forms of arthritis—with ankylosing spondylitis some patients experience a lessening of symptoms as they age, and some have had symptoms disappear altogether. However, ankylosing spondylitis progresses differently among patients, so it is advisable to develop and pursue a comprehensive treatment plan to provide both pain relief and minimize the risk of deformity.

A typical ankylosing spondylitis treatment plan can encompass several therapies, including:

• Rest and activity modification
• Pain management through prescription and/or over-the-counter medications
• Physical therapy and exercise
• Surgery (which is rare, except for joint replacements)

The first line of treatment usually centers on rest and/or activity modification to alleviate the symptoms of AS.

Rest and Activity Modification

Rest and/or modifying one’s daily activities can play a role in helping minimize the pain and other symptoms for patients. Many physicians will prescribe a period of rest if pain is too severe and is exacerbated by movement. Rest can be coupled with application of heat or warmth to alleviate stiffness, or ice or cold packs for local swelling, as needed.

In addition to refraining from activity, changing the intensity or type of activity or exercise can prevent further strain on affected joints.

Some straightforward activity modifications in a few daily activities can make a significant difference in how severely ankylosing spondylitis affects a patient’s life.

For example:

• Minimizing the weight of items a patient can pick up (e.g., less than 20 pounds)
• Switching from high impact exercise (like running) to a low impact exercise (such as swimming or pool therapy)
• Adjusting the work environment (e.g. using a drafting table in place of a standard desk or taking frequent breaks)

Patients should work with their doctors and therapists to review activities that should be modified or eliminated.

Complete rest is not usually recommended. Continuing moderate activity and exercise is generally recommended for people with ankylosing spondylitis to help maintain joint flexibility and general mobility.

 

Ankylosing Spondylitis Medications

Most treatment plans for ankylosing spondylitis include medication to help reduce the pain and stiffness experienced by patients. Once the pain and stiffness are controlled, a daily exercise program can be adopted to increase movement and flexibility. Several classes of medications can provide relief, including:

• Traditional pain management medications and steroid injections
• Disease modifying anti-rheumatic medications
• Biologics and immuno-suppressants.

Traditional Pain Management Medications

Many patients in the early stages of ankylosing spondylitis and with less severe forms of this type of arthritis find pain relief with well-known pain medications.

• Over-the-counter (OTC) non-steroidal anti-inflammatories (NSAIDs). These drugs are the most commonly used medications to treat the joint pain and back pain associated with ankylosing spondylitis. The group includes:
  • Aspirin
  • Ibuprofen (such as Advil, Motrin, and Nuprin)
  • Naproxen (such as Aleve).

For many people they reduce the pain and stiffness associated with ankylosing spondylitis. The main NSAIDs risks include gastritis, peptic ulcer disease, increase in blood pressure and possibly an increased risk of heart attack and stroke.

• Prescription drug therapies. Increasing evidence suggests that the class of NSAIDs known as cycloooxygenase-2-specific inhibitors, or COX-2 inhibitors (e.g., Celebrex), may reduce the risk of stomach problems associated with NSAIDs, although each patient will need to weigh the unique benefits and risks of COX-2 inhibitors. Other anti-inflammatory medications prescribed for the disease include prescription-strength naproxen (such as brand names Anaprox, Naprelan or Naprosyn), Indomethacin (such as Indocin), tolmetin (such as Tolectin), and Sulindac (such as Clinoril). Prescription NSAIDs carry the same risks as OTC NSAIDs (discussed above).
• Oral steroids (e.g. prednisone) are almost never used in treating ankylosing spondylitis. Steroid injections can be effective for acutely painful or swollen joints, such as the knee, but are almost never given in the spine joints.
• Corticosteroid injections (e.g. cortisone) may help to relieve enthesitis of the Achilles tendon or plantar fascia.

Disease-Modifying Anti-Rheumatic Drugs (DMARDs)

Drugs called DMARDs, which are typically used to treat rheumatoid arthritis (RA) and include sulfasalazine and methotrexate, have been used with limited benefits in ankylosing spondylitis patients.

• Sulfasalazine. This drug is primarily used to control the joint pain and joint swelling from arthritis of the small joints (e.g. for knees, not the spine). Side effects, however, can include headaches, abdominal bloating and nausea/vomiting. Rarely, patients can develop bone marrow suppression. Accordingly, it is important for doctors to regularly monitor the blood counts of any patients taking sulfasalazine.
• Methotrexate can also be effective in controlling symptoms associated with severe ankylosing spondylitis. Side effects include bone marrow suppression, oral ulcers, nausea, gastritis, and liver toxicity. Like sulfasalazine, use of methotrexate requires frequent monitoring of the blood counts and liver profile.

Biologics

These newer drug therapies are in a class of drugs also referred to as TNFα (tumor-necrosis factor alpha) blockers. These drugs aim to reduce the amount of TNF (a protein in the body that triggers inflammation leading to the symptoms of ankylosing spondylitis) produced by the immune system of patients. Some have been shown to actually slow the progression of the ankylosing spondylitis. In addition, they appear to treat both the joint pain associated with ankylosing spondylitis, as well as the spinal arthritis itself.

The four FDA-approved medications for ankylosing spondylitis are:

1. Enbrel (Etanercept). The first biologic approved to reduce signs and symptoms of ankylosing spondylitis. Enbrel is given as a weekly subcutaneous (under the skin) injection and can be delivered by the patient or a caregiver.
2. Remicade (Infliximab). Remicade is given as a 2-hour IV (Intravenous) infusion every 6 weeks by a rheumatologist.
3. Humira (Adalimumab). Humira is a subcutaneous injection given twice a month.
4. Simponi (Golimumab). Simponi is a subcutaneous, self-injected medication given once a month to treat active ankylosing spondylitis.

These four biologic medications are quite effective in reducing the inflammatory process which leads to the pain, fatigue and other symptoms of ankylosing spondylitis. Symptoms from injections such as redness, swelling, itching, rash or bruising sometimes occur at the injection site and typically last no more than 3 to 5 days. Patients should contact their doctor if these reactions don’t go away or worsen. Other, more serious, side effects have been reported with the biologics and must be discussed in detail with your treating physician.

As summarized here, there are several well-known and new medications available to ankylosing spondylitis patients. Patients should discuss the pros and cons of each with their doctor to determine if any of the medications identified here could be effective given their unique ankylosing spondylitis symptoms. All medications have side effects, and interaction among medications should be considered when developing a therapy plan.

Physical therapy and active, low impact exercise help considerably in the treatment of ankylosing spondylitis because they can prevent or slow development of a stooped posture which is a characteristic of many ankylosing spondylitis patients, as well as maintain movement and flexibility in affected joints.

Physical therapy generally will focus on promoting good posture, stretching to achieve greater flexibility, as well as strengthening exercises to support the spine. Deep-breathing exercises can also help patients focus their energy and increase lung capacity.

In addition to participating in physical therapy, some patients find relief from special support devices. Although they do not help in treating the disease, they may help maintain the posture or position achieved through physical therapy. These include:

• Lumbar supports (e.g., lumbar support pillows)
• Back braces
• Support mattresses or zero-gravity chairs.

Exercise can be difficult for ankylosing spondylitis patients when they are dealing with pain and changes to their posture. However, once pain is under control, it is important to remain active and exercise. Even moderate exercise can help patients maintain a healthy weight so the joints are not subjected to unnecessary stress. Physical activity and light stretching improve the flexibility needed to lessen pain.

Slow motion or non-weight bearing exercises are often prescribed for ankylosing spondylitis patients. These include:

• Tai Chi
• Yoga
• Swimming
• Pool therapy or water therapy
• Weight training
• Biking or stationary bicycling.

A qualified physical therapist or certified athletic trainer can help patients map out an effective program that both strengthens and minimizes the impact on affected joints.

Ankylosing Spondylitis Surgery

The majority of patients suffering from ankylosing spondylitis do not need to have surgery; however, surgery may be an option for patients suffering from severe ankylosing spondylitis and spinal deformities related to it, especially in the spine or hip joints. There are two types of surgery that may be an option for severe cases, depending on the patient’s clinical situation and symptoms: joint replacement or osteotomy.

Joint Replacement

For the hip, shoulder and knee problems related to this form of arthritis, joint replacement surgery can allow people to regain the use of joints that have been affected by ankylosing spondylitis. Hip, shoulder and knee replacement are becoming increasingly successful for people with severe pain and limited mobility in those joints.

Osteotomy

Surgical correction of the spine itself is also possible to address pronounced deformities such as a humpback or swayback, or the chin-on-chest posture characteristic of patients with advanced ankylosing spondylitis.

Indications that a patient may benefit from this type of surgery include:

• Severe, unremitting pain that is not sufficiently relieved by non-surgical care
• Neurological deficits
• Spinal instability
• Decreased ability to hold the head up and see horizontally
• Difficulty in completing everyday activities due to spinal deformity.

For patients who have not benefited from other forms of treatment, surgery can provide relief from some of the physical and associated emotional difficulties of spinal deformity caused by advanced ankylosing spondylitis. The decision to have surgery can be a difficult one, requiring patients to weigh the risks and benefits carefully.