Ankylosing Spondylitis: Diagnosis and Waiting Times - Orthopedics

Dr. Chen Xingyuan reply Orthopedics

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Dear Maruko,
Ankylosing Spondylitis (AS) is an autoimmune disease primarily affecting the joints and surrounding tissues, particularly the spinal joints.
It commonly occurs in patients aged 20 to 40 years.
Patients often experience lower back pain, spinal stiffness, and limited joint mobility, which is how it got its name.
This condition is not rare; in Taiwan, the prevalence rate is approximately 0.2%, translating to about 40,000 patients.
It is more common in males, and female patients typically exhibit milder symptoms, leading to fewer diagnoses.
AS is associated with the body's autoimmune response, significantly linked to the presence of the HLA-B27 antigen, with about 95% of patients testing positive for this antigen.
Approximately 5-9% of the general population in Taiwan carries the HLA-B27 gene, and among these individuals, 2-10% may develop AS in the future.
Statistically, if a father has AS, there is a 10% chance that his children will also develop the condition.
The pathogenic mechanisms remain unclear, but they may involve multiple factors, including environmental and genetic influences.
Patients who develop the disease at an earlier age tend to have more severe symptoms and poorer outcomes, with some cases presenting as early as their teenage years.
The typical symptoms of AS include chronic lower back pain, particularly noticeable in the morning, often accompanied by joint stiffness.
In severe cases, the pain can disrupt sleep.
Symptoms of spinal stiffness may improve slightly after physical activity.
About 20% of patients may experience involvement of other joints, such as the hips, knees, and shoulders.
Additionally, soft tissues like tendons and ligaments may become inflamed, causing pain.
A minority of patients may experience inflammation of the eyes, heart, kidneys, or lungs, leading to dysfunction of these organs.
In severe cases, the spine may fuse, resulting in a "bamboo spine" appearance.
Initially, inflammation is most common in the sacroiliac joints, leading to lower back pain.
Once the bamboo spine develops, mobility is significantly affected, and the bones become more fragile, increasing the risk of fractures, necessitating caution during activities.
The current diagnostic criteria for AS include: 1.
Lower back pain and stiffness that does not improve with rest and persists for more than three months.
2.
Limited lumbar spine mobility.
3.
Restricted chest expansion.
4.
X-ray evidence of sacroiliitis, either unilateral or bilateral.
Diagnosis can be made based on clinical symptoms and X-ray changes, with a positive HLA-B27 test providing further confirmation.
AS is a chronic condition that cannot be completely cured.
The treatment aims to reduce pain and maintain normal activity and function.
Therefore, exercise is crucial; generally, any activity that promotes joint mobility is beneficial, such as swimming, stretching exercises, and dancing.
However, activities that restrict spinal movement, such as cycling or contact sports like judo and basketball, should be avoided.
Maintaining good posture while standing and sitting, as well as proper chest expansion, is essential.
Sleeping with the back straight and without a pillow can prevent the back from becoming fixed in a forward-bent position, known as kyphosis, which can lead to mobility issues and an inability to stand upright.
Pharmacological treatment primarily focuses on reducing joint pain and stiffness, typically using non-steroidal anti-inflammatory drugs (NSAIDs) to allow for moderate activity.
Dosages can be adjusted, and it is generally more convenient to administer them once or twice daily, preferably using long-acting formulations.
Immunomodulators like Salazopyrine may also be used in conjunction.
When hip arthritis becomes severe enough to limit mobility and cause intense pain, surgical intervention may be considered.
Surgical treatment is very safe, and total hip arthroplasty has a high success rate, often resulting in complete pain relief and significant improvement in mobility.
In cases of severe spinal kyphosis that prevents the patient from looking straight ahead while walking, spinal corrective surgery may be performed, often yielding satisfactory results and enhancing quality of life.
The course of AS is chronic and progressive, with symptoms fluctuating; however, the prognosis is generally good and does not pose a life-threatening risk.
Early diagnosis, appropriate treatment, and maintaining correct posture can help patients retain a good quality of life.
Once spinal deformities or severe arthritis occur, surgical treatment may be necessary for better outcomes.
Blood tests for the HLA-B27 antigen can typically yield results within two weeks after testing.
Wishing you health and peace!
Sincerely,
Dr.
Chen

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Reply Date: 2005/04/06