Although the cause of Ankylosing Spondylitis is not fully understood, genetic factors play a part, and the condition may be triggered by some sort of environmental event (such as a viral infection) occurring in someone who is genetically predisposed.
A number of genes have been identified as possibly to blame. It’s been known for some time, for example, that there is a link between Ankylosing Spondylitis and people with a certain blood type called Human Leukocyte Antigen B27 (HLA B27), indicating a genetic link.
The underlying process involves episodes of inflammation affecting the joints of the spine, as well as other joints such as the pelvis, hips, ribs, feet, shoulders, knees, wrists and ankles. The inflammation particularly occurs at the points where ligaments and tendons attach to the bone. As the inflammation subsides, new bone grows, replacing the elastic tissue of the tendons and ligaments and so making the joints stiff or fused together.
In some cases of Ankylosing Spondylitis, other parts of the body such as the eyes, bowel, lungs and heart may be affected.
What Are The Symptoms?
Ankylosing Spondylitis may cause lower back pain that can spread and be felt in the buttocks and thighs, lower back stiffness. Other symptoms include tiredness, weight loss and a mild fever.
Pain and stiffness in the affected joints are usually worse early in the morning and after resting, but improve with exercise as the day progresses.
Because the spine loses its normal shape, people may find their back becomes bent forwards. This can make walking and moving around painful and difficult.
If the ribs and chest wall become stiff or fused, then it may become more difficult to breathe in and the affected person may rely on moving their diaphragm to shift air in and out of the lungs. They may find it harder to get over colds and respiratory infections.
Who's Affected By Ankylosing Spondilitis?
AS usually starts in the late teens and early 20s. Men are affected more than women.
What's The Treatment?
It's not possible to prevent Ankylosing Spondylitis, AS and there's no cure. However, people with AS can prevent further problems by sticking to a healthy weight, eating a diet rich in calcium, vitamin D and protein, and avoiding contact sports that may damage the joints.
Physiotherapy that includes back and breathing exercises helps to keep the spine and joints strong. Keeping active and taking regular exercise is key to keeping symptoms under control, improving posture and preventing spine deformities.
Paracetamol or anti-inflammatory medication, such as ibuprofen, are used to relieve pain and inflammation. More powerful anti-inflammatory drugs such as steroids may be recommended, especially during acute flare-ups of the condition. Other more powerful drugs that are sometimes used include anti-TNF therapy and Disease Modifying Anti-Rheumatic Drugs (DMARDS).
In serious cases, surgery may be needed, especially to replace damaged joints or correct the shape of the spine.
Unlike most inflammatory conditions, many people find their ankylosing spondylitis gets much better as they get older.