Ankylosing Spondylitis (AS)
Ankylosing spondylitis (AS, from Greek ankylos, fused; spondylos, vertebra; -itis, inflammation), previously known as Bechterew's disease (or syndrome) and Marie-Strumpell disease, is a chronic inflammatory disease of the axial skeleton with variable involvement of peripheral joints and nonarticular structures. It mainly affects joints in the spine and the sacroiliac joint in the pelvis, and can cause eventual fusion of the spine.
Ankylosing spondylitis is a member of the group of the spondyloarthropathies with a strong genetic predisposition. Complete fusion results in a complete rigidity of the spine, a condition known as "bamboo spine". There is no cure for AS, although treatments and medications can reduce symptoms and pain.
Signs and symptoms appear gradually, usually around 23 years of age. Initial symptoms are typically chronic pain and stiffness in the middle part of the spine or the entire spine, often with pain referred to one or the other buttock or the back of the thigh from the sacroiliac joint. Since the initial signs and symptoms are not specific for ankylosing spondylitis, there is a lag-time between onset of disease and diagnosis, which averages between 8.5 years and 11.4 years.
About 40 percent of AS patients experience inflammation in the anterior chamber of the eye (uveitis), causing redness, eye pain, floaters and photophobia. Visual acuity is usually maintained and the fundus is normal. This is thought to be due to the association that both AS and uveitis have with the inheritance of the HLA-B27 antigen. Other common symptoms of AS include: chest pain and generalized fatigue. When the condition presents before the age of 18, it is relatively likely to cause pain and swelling of large limb joints, particularly the knee. In prepubescent cases, pain and swelling may also manifest in the ankles and feet, where calcaneal spurs may also develop.
Pain is often severe at rest, but improves with physical activity. However, many experience inflammation and pain to varying degrees regardless of rest and movement.
Some of the therapies that have been shown to benefit AS patients include:
Exercise programs, either at home or supervised, are better than not having an exercise program;
Group exercises are better than home exercises;
Extending regular group exercises with few weeks exercising at a spa resort is better than group exercises alone.
Moderate-to-high impact exercises like jogging are generally not recommended or recommended with restrictions due to the jarring of affected vertebrae that can worsen pain and stiffness in some patients.
Prognosis is related to disease severity. AS can range from mild to progressively debilitating and from medically controlled to refractory. Some cases may have times of active inflammation followed by times of remission resulting in minimal disability, while others never have times of remission and have acute inflammation and pain, leading to significant disability.
Over a long-term 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.