We all have mornings when we wake up a bit stiff. We all know the achy feeling that comes from working too hard in the garden, sitting too long at the computer or sleeping in an awkward position. And, from time to time, we have all suffered pain because we've lifted a heavy object in a slightly wrong way. Even a particularly ferocious sneeze can cause a twinge of discomfort. But arthritis goes far beyond these occasional aches and pains.
The condition that we commonly refer to as arthritis includes a number of diseases that result in inflammation, pain and stiffness, primarily in the joints and connective tissues. Connective tissues are the supporting structures for joints, such as muscles, cartilage, ligaments and tendons. In many cases, these diseases affect other parts of the body as well. Arthritic disorders may be are chronic, but some, such as gout, are intermittent. The conditions that are truly inflammatory (that is, with actual joint inflammation present) cause warmth and swelling, whereas others are degenerative, in which cartilage lining the joint wears out and the amount of inflammation is minor.
The ends of bones meet at the joint, where they are cushioned by cartilage, a layer of smooth pliable tissue. Around many of the larger joints, such as the knee, hip and shoulder, there is a pad-like sac or cavity called the bursa, which is lined with cells similar to those lining the joint. In addition to acting as a buffer to reduce friction between the muscle, tendon tissue and bone, this inner lining produces a fluid, synovial fluid, that keeps the joints lubricated and provides nutrients. Ligaments connect and support bones to keep them in proper alignment, whereas tendons connect muscles to bones. Joints move when a muscle on one side of a joint contracts and pulls on the tendons that attach to a bone on the other side of the joint.
The word arthritis means joint inflammation. Inflammation, a natural part of the body's response to injury and infection, is a complex process that produces swelling, pain, warmth and redness. But inflammation is not only a response to injury, it may perpetuate injury as well. Significant problems arise when inflammation is persistent, intense or recurrent or spreads to other areas of the body.
Joints and the surrounding areas become inflamed for a number of reasons, including trauma, disease, infection or merely wear and tear, which naturally occurs over time. Many forms of arthritis are thought to result from the uncontrolled inflammation of an autoimmune disease, in which the body's defense mechanism malfunctions and attacks its own tissues. At other times, the joint area becomes inflamed and tender for no apparent reason.
When joints become arthritic, swelling causes stiffness, rigidity and tissue damage. Pain, which is the body's signal that something is wrong, occurs as the joint is moved to the brink of its own limits. As mobility decreases, the muscles surrounding the joint also weaken, allowing for further injury to the joint. Over time, the cartilage breaks down, the bone erodes and the joints become misshapen. It is this process, regardless of the source, that may develop in the worst forms of arthritis.
There are more than 100 different types of arthritis, and each has its own characteristic symptoms and its own course. In addition, the way in which the disease progresses varies from individual to individual. If you suffer from an arthritic condition, you will most likely experience pain and limited movement at the involved sites. In chronic forms of arthritis, there may be times when the disease is active (flares) and times when it is inactive (remission). Depending on the specific condition and how severe it is, arthritis can interfere with even the most ordinary activities, such as walking, dressing or bathing. In the most inflammatory types of arthritis, such as rheumatoid arthritis, pain and stiffness are more severe in the morning or on certain days. Sometimes symptoms disappear completely for considerable stretches of time, only to flare up again later.