Arthritis literally means "inflamed joints" and incorporates more than 150 disorders characterised by pain, swelling, tenderness and limited movement. Such disorders can affect not only the joints, but also other connective tissues, including muscles, tendons and ligaments as well as the protective covering of internal organs. Arthritis may be caused by inflammation in a joint, be degeneration of a joint as a person becomes older, or by a disorder of which arthritis is a symptom. A few examples of the more common arthritic conditions: Osteoarthritis sometimes called degenerative joint disease or osteoarthrosis - is one of the oldest and most common types of arthritis. It is characterised by the progressive loss of cartilage, the slippery material that cushions the ends of bones, together with changes in the bone below the cartilage leading to bony overgrowth. Cartilage breakdown causes bones to rub against each other, causing pain and loss of movement. Most commonly affecting middle-aged and older people, and can range from very mild to very severe. It affects hands and weight-bearing joints such as knees, hips, feet and the back, with symptoms of pain, stiffness, inflammation and loss of mobility. Also, if you"ve had a severe injury in earlier life that caused cartilage damage, you may be more susceptible to the degenerative changes. Unlike some other forms of arthritis, osteoarthritis only affects joints, and not internal organs. Although there is no cure for osteoarthritis there is a variety of known treatments and management techniques that help people control and reduce the effects of the disease. Rheumatoid arthritis is an autoimmune disease that causes chronic inflammation of the joints, the tissue around the joints, as well as other internal organs. (Autoimmune diseases are illnesses that occur when the body tissues are mistakenly attacked by their own immune system). Although RA is often a chronic condition, it tends to vary in severity and may flare up or be well controlled. Periods of increased disease activity - called flare-ups or flares - alternate with periods of relative remission, during which the swelling, pain, difficulty in sleeping and weakness fade or disappear. Joint involvement in RA affects both sides of the body equally; the arthritis is therefore referred to as symmetrical. It is characterised by the inflammation of the membrane lining the joint, which causes pain, stiffness, warmth, redness and swelling. The inflamed joint lining can invade and damage bone and cartilage. Inflammatory cells release enzymes that may digest bone and cartilage. The involved joint can lose its shape and alignment, resulting in pain and loss of movement. It most often begins in early adult life, between the ages of 30 and 40yrs. In children, the condition is known as juvenile rheumatoid arthritis. Lower back pain is rarely a symptom but one can experience neck pain. Although rheumatoid arthritis can have serious effects on a person's life and well-being, current treatment strategies - including pain relief medications, a balance between rest and exercise, and patient education and support programs - allow most people with the disease to lead active and productive lives. In recent years, research has led to a new understanding of rheumatoid arthritis and has increased the likelihood that, in time, researchers can find ways to greatly reduce the impact of this disease. Ankylosing Spondylitis is a form of chronic inflammation of the spine and the sacroiliac joints (one of the joints in the pelvis, formed by two bones, the sacrum and the ilium.) Ankylosing spondylitis is also referred to as spondylitis or AS, and is the main disease among the related conditions called seronegative spondylarthropathies. Chronic inflammation causes pain and stiffness in and around the spine. Over time, chronic spinal inflammation (spondylitis) can lead to a complete cementing together (fusion) of the vertebrae, a process called ankylosis. Ankylosis causes total loss of mobility of the spine. It affects males more than females and heredity may play a role in determining who gets ankylosing spondylitis. The associated pain is worse during periods of rest or inactivity and people often awaken in the middle of the night with back pain. Typically, symptoms lessen with movement and exercise. Ankylosing spondylitis is also a systemic rheumatic disease. Therefore, it can cause inflammation in other joints away from the spine, as well as other organs, such as the eyes, heart, lungs, and kidneys. It is important to remember that AS is a disease of varying severity and many people continue to live normal lives both personally and professionally. And while there is no cure, AS can generally be successfully managed to minimise its potential effects.