Oteoarthritis (OA) is a chronic disorder associated with damage to the cartilage and surrounding tissues and characterised by pain, stiffness, and loss of function.
Arthritis due to damage of joint cartilage and surrounding tissues becomes very common with aging.
Pain and stiffness are common following awakening or inactivity and disappears within 30 minutes, particularly if the joint is moved.
Osteoarthritis, the most common joint disorder, often begins in the 40’s and 50’s. Almost all people to some degree by age 80. Before the age of 40, men develop osteoarthritis more often than women, often because of injury. Only 50% of people have some evidence of osteoarthritis on x-rays (often by age 40), have any symptoms. From age 40 to 70, women develop the disorder more often than do men. After age 70, the disorder develops in both sexes equally.
What Causes Osteoarthritis?
Normally, joints have such a low friction level that they are protected from wearing out. Even after years of typical use, overuse, or injury. Osteoarthritis is caused most often by tissue damage. In an attempt to repair a damaged joint, chemicals accumulate in the joint and increase the production of the components of cartilage.
Next, the cartilage may swell because of water retention, become soft, and then develop cracks on the surface. Tiny cavities form in the bone beneath the cartilage, weakening the bone.
The attempt of the tissues to repair the damage may lead to new growth of cartilage, bone, and other tissue. Bone can overgrow at the edges of the joint, causing bumps (osteophytes) that can be seen and felt. Ultimately, the smooth, slippery surface of the cartilage becomes rough and pitted, so that the joint can no longer move smoothly and absorb impact.
All the components of the joint—bone, joint capsule (tissues that enclose most joints), synovial tissue (tissue lining the joint cavity), tendons, ligaments, and cartilage—fail in various ways, thus altering the function of the joint.