Arthritis definition, acute or chronic inflammation of a joint, often accompanied by pain and structural changes and having diverse causes, as infection, define arthritis deposition, or injury. 4 million recipients identical to the rate found in the general population. Inflammation of a joint or joints resulting in pain and swelling.
2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company. Acute or chronic inflammation of one or more joints, usually accompanied by pain and stiffness, resulting from infection, trauma, degenerative changes, autoimmune disease, or other causes. 2005 by Houghton Mifflin Company. What does Tis the Season mean? Arthrosis is a broad term for degenerative and other diseases of the joint and is more commonly understood in the form of osteoarthritis.
Therefore the term arthosis is sometimes considered to be synonymous with osteoarthritis while at other times arthrosis is seen as a prelude to or the early stages of osteoarthritis. Arthrosis is not a commonly used term to describe degenerative joint disease. To fully grasp the meaning of arthrosis, it is important to first understand the anatomy of the joint. The ends of bones that are part of a joint have a smooth surface known as the subchondral bone. Over it lies the articular cartilage which is strong yet flexible connective tissue that protects the bone, allows for easier movement between the surfaces and also acts as a shock absorber. It is this cartilage that is part of the articular surface and not the bone itself.
An outer capsule secures the joint. Cartilage is a flexible connective tissue. The cartilage cells are known as chondroblasts which produce and release large amounts of different substances, like collagen, into the extracellular matrix. It is this matrix that is responsible for the characteristics of cartilage namely its strength and flexibility. Sometimes chondroblasts are trapped within the matrix and is then referred to as chondrocytes.
The cartilage is constantly undergoing wear-and-tear. Cartilage cells, however, are constantly replenishing the cartilage matrix and therefore maintaining the integrity of the cartilage. With age, the ability to replenish any tissue diminishes but does not cease altogether. Even in younger people, the body’s ability to replenish tissue is limited by time.
If there is constant and excessive wear and tear of the articular cartilage which exceeds the replenishing time, then the cartilage will erode. This is the reason why arthrosis is more commonly seen in the elderly and more frequently in those who are very active. There are also other factors that further complicate this like inflammatory mediators which affect normal cartilage regeneration although there is little or no inflammation of the joint. Similarly if there is some underlying disease which slows or stops the activity of the cartilage cells, the cartilage will eventually wear out. As it weakens, bits of cartilage break off and float around in the joint space. The bone tissue is now exposed to the same wear and tear as the articular cartilage but lacks the flexibility and regenerative capability. It is then destroyed over time and this condition is known as osteoarthritis.
The symptoms of arthrosis develops very slowly. In the early stages of cartilage erosion, there is no symptoms. Furthermore this is a degenerative rather than inflammatory joint condition and can therefore go by unnoticed for long periods. Once the symptoms start then it gradually worsens over a long period of time. The pain is typically isolated to the affected joint. It may be worse during and after movement of the affected joint. In milder cases, the pain may be absent until a person moves and it persists for a short while after.
Rest often relieves the pain. In some cases, firm pressure on the skin over the joint will elicit pain. This tenderness of the joint is not usually accompanied by swelling as is the case in inflammatory causes of joint pain like rheumatoid arthritis. The stiffness of the joint is another common symptom. It is most prominent after waking up in the morning and with long periods of inactivity. Moving around may ease the stiffness but excessive movement will ultimately lead to pain. The stiffness tends to worsen over time as the condition progresses.
Even when the stiffness eases, the normal range of motion may not be the same. This loss of flexibility hampers a person’s level of mobility over time. A grating sound may be heard from the joint particularly as the condition progresses. Sometimes this can also be heard as a snapping or clicking noise, depending on the joint that is affected. Normally the articular cartilages of either ends of the bone rub together to some extent.