What is ankylosing spondylitis?

Ankylosing spondylitis is a generalised chronic inflammatory disease, mainly affecting the spine and sacroiliac joints. It is characterised by pain or stiffness of the back, often with involvement of the hips and shoulders.

Statistics on ankylosing spondylitis

1 in 2,000 births. Males tend to be affected more severely and at an earlier age. Usual onset is between 15 and 25 years of age.

Risk factors for ankylosing spondylitis

Ankylosing spondylitis tends to run in families. Relatives may have the disease, or another disease that is associated, for instance reactive arthritis, psoriatic arthritis or enteropathic arthritis.
It is thought that the manifestation of these disease is due to both a genetic component and some external triggering event such as infection.

Progression of ankylosing spondylitis

The disorder is first manifested by episodic inflammation of the sacroiliac joints in the late teens or early 20’s. Pain in one or both buttocks and lower back pain and stiffness are typically worse in the morning, and relieved by exercise.

Symptoms of ankylosing spondylitis

Most people with ankylosing spondylitis are young men in their late teens or early 20s who complain of persistent back pain and early morning stiffness. A smaller number experience pain in their hands or feet. Pronounced stiffness of the spine is the most typical sign, with diminished movements in all directions.
In severe cases the entire backbone may be fixed in a rigid position (‘poker back’), and chest expansion on breathing is reduced. Sometimes the hip joints are involved and become completely fused with resulting loss of movement. Some people may also develop eye, heart and breathing complications.

How is ankylosing spondylitis diagnosed?

Diagnosis is made on the basis of clinical examination, spinal x-ray and blood tests.

Prognosis of ankylosing spondylitis

Prognosis is good if an early diagnosis is made. Most patients never require hospitalisation. With special exercises and pain relief, most patients are able to lead independent lives and be fully employed.

How is ankylosing spondylitis treated?

Patients are encouraged to exercise to maintain spinal mobility and function. Surgery is generally not recommended unless disease is severe. Pain is treated with anti-inflammatory drugs with good effect.


  1. Solomon L, Warwick D, Apley AG, Nayagam S. Apley’s Concise System of Orthopaedics and Fractures (2nd edition). London: Arnold; 2001.
  2. Collier JAB, Longmore JM, Scally P. Oxford Handbook of Clinical Specialties (6th edition). Oxford: Oxford University Press; 2003.
  3. Kumar P, Clark M (eds). Clinical Medicine (5th edition). Edinburgh: WB Saunders Company; 2002.

All content and media on the HealthEngine Blog is created and published online for informational purposes only. It is not intended to be a substitute for professional medical advice and should not be relied on as health or personal advice. Always seek the guidance of your doctor or other qualified health professional with any questions you may have regarding your health or a medical condition. Never disregard the advice of a medical professional, or delay in seeking it because of something you have read on this Website. If you think you may have a medical emergency, call your doctor, go to the nearest hospital emergency department, or call the emergency services immediately.