Ankylosing Spondylarthritis

Definition

Definition of Ankylosing Spondylarthritis
Ankylosing spondylitis, previously known as Bekhterev's disease, Bekhterev syndrome, and Marie-Strümpell disease is a chronic inflammatory disease of the axial skeleton with variable involvement of peripheral joints and nonarticular structures. AS is a form of spondyloarthritis, a chronic, inflammatory arthritis and autoimmune disease. It mainly affects joints in the spine and the sacroiliac joint in the pelvis, and can cause eventual fusion of the spine.

Symptoms

Symptoms of Ankylosing Spondylarthritis
The typical patient is a young male, aged 20–40; however, the condition also presents in females. The condition is known to be hereditary. Symptoms of the disease first appear, on average, at age 23 years. These first symptoms are typically chronic pain and stiffness in the middle part of the spine or sometimes the entire spine, often with pain referred to one or other buttock or the back of thigh from the sacroiliac joint.

Symptoms appear gradually. Initially they are usually not specific for ankylosing spondylitis. The average onset-to-diagnosis lag time has been estimated to be approximately 8.5 years to 11.4 years.

Causes

Causes of Ankylosing Spondylarthritis
Ankylosing spondylitis has no known specific cause, though genetic factors seem to be involved. In particular, people who have a gene called HLA-B27 are at significantly increased risk of developing ankylosing spondylitis.

As ankylosing spondylitis worsens and the inflammation persists, new bone forms as part of the body's attempt to heal. This new bone gradually bridges the gap between vertebrae and eventually fuses sections of vertebrae together. Those parts of your spine become stiff and inflexible. Fusion can also stiffen your rib cage, restricting your lung capacity and function.

Diagnosis

Diagnosis of Ankylosing Spondylarthritis
There is no direct test to diagnose AS. A clinical examination, MRI and X-ray studies of the spine, which show characteristic spinal changes and sacroiliitis, and a simple genetic marker blood test are the major diagnostic tools. A drawback of X-ray diagnosis is the signs and symptoms of AS have usually been established as long as 8–10 years prior to X-ray-evident changes occurring on a plain film X-ray, which means a delay of as long as 10 years before adequate therapies can be introduced. Options for earlier diagnosis are tomography and magnetic resonance imaging of the sacroiliac joints, but the reliability of these tests is still unclear. The Schober's test is a useful clinical measure of flexion of the lumbar spine performed during examination.

Treatment

Treatment of Ankylosing Spondylarthritis
No cure is known for AS, although treatments and medications are available to reduce symptoms and pain.

Physical therapy and exercise, along with medication, are at the heart of therapy for ankylosing spondylitis. Physiotherapy and physical exercises are preceded by medical treatment to reduce the inflammation and pain, and are commonly followed by a physician. This way the movements will help in diminishing pain and stiffness, while exercise in an active inflammatory state would just make the pain worse. Normal occupations may be precluded by the symptoms of the disease.

Some may require the help of walking aids, such as a cane, to help assist in balance and relieve some pressure on affected joints while walking and standing. Many with AS find it very difficult to sit or stand for prolonged periods of time, which can be as little as 20 minutes; therefore, many need to alternate times of sitting and standing, as well as times of rest.

Medical professionals and experts in AS have speculated that maintaining good posture can reduce the likelihood of a fused or curved spine which occurs in a significant percentage of diagnosed persons.

Prognosis

Prognosis of Ankylosing Spondylarthritis
AS can range from mild to progressively debilitating and from medically controlled to refractive. Some have times of active inflammation followed by times of remission, while others never have times of remission and have acute inflammation and pain.

Unattended cases of AS accompanied by dactylitis or enthesitis, especially when spine inflammation is not yet active, may result in a misdiagnosis of normal rheumatism. In a long-term undiagnosed period, osteopenia or osteoporosis of the AP spine may occur, causing eventual compression fractures and a back "hump". Typical signs of progressed AS are the visible formation of syndesmophytes on X-rays and abnormal bone outgrowths similar to osteophytes affecting the spine. The fusion of the vertebrae paresthesia is a complication due to the inflammation of the tissue surrounding nerves.

Organs commonly affected by AS, other than the axial spine and other joints, are the heart, lungs, eyes, colon, and kidneys. Other complications are aortic regurgitation, Achilles tendinitis, AV node block and amyloidosis. Owing to lung fibrosis, chest X-rays may show apical fibrosis, while pulmonary function testing may reveal a restrictive lung defect. Very rare complications involve neurologic conditions such as the cauda equina syndrome.

Prevention

Prevention of Ankylosing Spondylarthritis
Because genetic factors appear to play a part in ankylosing spondylitis, it's not possible to prevent the disease. However, being aware of any personal risk factors for the disease can help in early detection and treatment. Proper and early treatment can relieve joint pain and may help to prevent or delay the onset of physical deformities.