You want to hop on the bike, hit the tennis court or work on the car, but stiffness in the joints causes you to hold off. This may be a problem shared by millions of Americans, new research shows.

There's osteoarthritis. And rheumatoid arthritis. And infectious arthritis, childhood arthritis, Still's disease, lupus, Sjogren's disease and many more. In total, there are more than 100 kinds of arthritis.

Arthritis symptoms can get in the way of many social activities, which can affect quality of life. So researchers wanted to know which aspects of arthritis most affected social life.

Inflammation is the reason patients with rheumatoid arthritis develop swollen and painful joints. But inflammation is not unique to rheumatoid arthritis; it is also behind other painful joint conditions.

A little over half a century ago, cigarettes were not seen as a danger. Some doctors even recommended them. Today, we know that cigarettes are linked to a variety of health problems, including arthritis.