The word arthritis literally means joint inflammation, but it is often used to refer to a group of more than 100 rheumatic diseases that cause pain, stiffness, and swelling in the joints. The most common are osteoarthritis, rheumatoid arthritis, fibromyalgia, and gout. Most forms of arthritis are associated with pain that can be divided into two categories: acute and chronic. Acute pain is temporary. It can last a few seconds or a few minutes but diminishes as healing occurs. Acute pain is associated with burns, cuts and fractures. Chronic pain, such as that felt by people with arthritis, ranges from mild to severe and can last days, months, years or even a lifetime.
Osteoarthritis is one of the most frequent causes of physical disability among adults. More than 20 million people in the United States, alone, have the disease. By 2030, according the National Institutes of Health (NIH), 20 percent of all Americans – about 70 million people – will have passed their 65th birthday and will be at a higher risk of osteoarthritis.