Ankylosing spondylitis (rheumatoid spondylitis, Marie-Strümpell disease, von Bechterew disease) is a chronic, inflammatory disorder primarily involving the sacroiliac joints, the axial skeleton, peripheral joints and entheses. The etiology of Ankylosing spondylitis is unknown, though genetic factors seem to be involved (HLA-B27).
Ankylosing spondylitis is a type of arthritis causing chronic multisystem inflammation mainly of the spine with differential involvement of various peripheral joints like the interphalangeal joints and other non-articular structures. It primarily affects the spine, sacroiliac joints in the pelvis and hip joints. Ankylosing spondylitis is a form of inflammatory arthritis. Enthesitis is a major feature of this disorder which involves inflammation of the place where ligaments and muscles are attached to the bones and accounts for much of the pain and rigidity. This can finally lead to severe bony fusion of the joints resulting in decreased flexibility and mobility.
Ankylosing spondylitis is a systemic, rheumatic disorder that can affect and involve multiple organs such as the eye, heart, lungs, skin as well as the gastrointestinal tract.
Ankylosing spondylitis is the most important cause for inflammatory back pain in young adults . Other important associations of this disorder include peripheral arthritis and non-articular features such as iritis and uveitis.
Ankylosing spondylitis has no definite cause, but is said to be a genetically determined disease, susceptibility to which is related to the presence of HLA-B27 antigen . In general, people who have this gene are at a higher risk of developing spondylitis.
Since HLA-B27 antigen is found equally in men and women, the incidence of the disease should also be equal, but it affects men more than women. White people with ankylosing spondylitis almost always carry a copy of the HLA-B gene. Family members are at a higher risk due to the chances of inheriting the carrier gene.
The disorder is more common in men than women, and in women the severity of the spondylitis is much milder . Population surveys using radiological findings as a criterion have shown a male preponderance. Onset of symptoms is usually between 15 to 35 years of age and very rarely occurs in elderly people.
The exact aetiology of this disorder is not clearly established, however, pathogenesis of this condition has clear association with HLA-B27 gene . The primary pathology is enthesitis, which is considered a hallmark of ankylosing spondylitis. Tumour necrosis factor- alpha (TNFα) and Interleukin-1 are also associated with Ankylosing spondylitis. There is a supposed interaction between the HLA-B27 gene and the CD8+ T cell which triggers the immune system to attack the cartilage .
In Ankylosing spondylitis, the rheumatoid factor tests are negative and the typical histological finding is an inflammation of the enthesis which is the insertion of tendon, ligament, capsule or surrounding fascia into bone .
In ankylosing spondylitis, the enthesis is inflamed at the vertebrae, showing that the entheseal fibrocartilage is a major target of the immune system. Early leisons usually occur in the sacroiliac joints which include subchondral granulation that erodes the joint and is slowly replaced by fibrocartilage and ultimately ossification. In the spine, it is seen at the interface of the vertebra and annulus fibrosus of the intervertebral discs. These discs ultimately undergo ossification which results in syndesmophytes. This leads to ‘bamboo spine’ appearance and fusion of the vertebrae.
In addition, there may be mild inflammation of the synovium which is present as a cushion around the joints.
With progression of the disease there is destruction of nearby articular and joint tissues as well, resulting in complete fusion leading to immobility.
Most of the cases of ankylosing spondylitis do well, and death is rarely associated with this condition . Despite restriction of spinal movement, patients are able to lead a normal life with a correct exercise regime.
In women, the disease is milder with little restriction and no physical deformity. Ankylosing spondylitis improves with age but does not resolve completely.
A typical case of ankylosing spondylitis presents with a gradual onset of lower lumbar pain which is of an inflammatory type. Fatigue may present along with the inflammation .
The first symptom of pain may arise from sacroilititis, with pain in the buttocks radiating down the back of both the legs. The pain can lead to stiffness and rigidity. The symptoms of pain and stiffness are worse in the morning or after long periods of inactivity. Heat and warmth generally ameliorate the condition. Once fusion occurs, pain reduces but flexibility and mobility of the spine are severely affected. This occurs due to overgrowth of bones resulting in bony fusion. Chronic spondylitis leads to loss of lumbar lordosis and increased kyphosis which may cause difficulty in breathing which is a serious complication of this disorder.
People with this disorder can also have arthritis of other joints, showing the typical signs of inflammation. If peripheral polyarthritis occurs, usually joints of lower limb are affected. Plantar faciitis may cause heel pain due to inflammation of the tendon or even pain at the back of the ankle leading to Achilles tendon .
There is always a time lag between the onset of the disease and the diagnosis as the disease has an insidious onset .
An accurate diagnosis by the physician is mainly done based on these main criteria:
Physical examination reveals signs of inflammation and decreased range of movements mainly seen in the spine. There may be tenderness on sacroiliac joints and postural abnormalities.
Radiographs of the spine reveal irregular margins with erosion of sacroiliac joints which are not seen in early stages. There may be fusion of joints along with demonstration of syndesmophytes between the vertebrae.
Blood tests to detect the HLA –B27  are not always useful as one should bear in mind that many people can carry this gene. Other blood tests can include an ESR to support inflammation.
Ankylosing spondylitis cannot be cured and treatment mainly focuses on relieving pain. Physical therapy and exercise enable the patient to carry out daily activities.
There is no prevention for this inherited condition. Prevention is aimed at preventing complications and minimising pain. Physiotherapy  and exercise programmes are helpful for keeping the spinal cord flexible, thus enabling easy
movements. Quitting smoking is advised for long term benefits.
Ankylosing spondylitis is a disorder that causes chronic inflammation of the joints in your spine, resulting in severe pain, stiffness and immobility. It can also affect other joints of the body as well as multiple organs of the body like eyes, kidney, heart, lungs and the skin. The exact cause is unknown due to which there is no known prevention or cure. It is predominantly seen in men than women.
The most common complaint is lower back pain which radiates till the hip. The onset of the pain is slow and gradual which can increase to stiffness and restriction of movement. Ankylosing spondylitis can also affect other organs mainly the eye, which should be treated immediately as it can lead to severe complications.
It is better to consult a medical care provider for correct diagnosis. A simple physical examination with a few tests is sufficient to confirm the condition.
The treatment is aimed at reducing pain and suppressing inflammation. There is no single treatment. Treatment consists of exercise and physical therapy to ease movements and prevent any physical deformity, which once occurs, is more difficult to treat. Exercise should be done regularly. Medications given are non-steroidal anti-inflammatory drugs to reduce inflammation.
Artificial joint replacement surgery is commonly performed for advanced cases affecting hip or knee.
The condition responds well to physical therapy, exercise and medications and does not frequently need surgery. Swimming is a good exercise for ankylosing spondylitis. Patients are advised not to use pillows to prop up their head or legs as it may aggravate fusion of the bones in the joints.
Ankylosing spondylitis does not get cured completely and the patient may show periods of relapse and remission. The main objective of the treatment is to reduce pain, maintain a good posture, facilitate easy movements and prevent deformity thus enabling patients to lead fairly normal lives.