is arthritis actually osteoarthritis?
Osteoarthritis. Osteoarthritis is the most common form of arthritis in the knee. It is a degenerative,wear-and-tear type of arthritis that occurs most often in people 50 years of age and older, but may occur in younger people, too. In osteoarthritis, the cartilage in the knee joint gradually wears away.he most common types of arthritis are osteoarthritis and rheumatoid arthritis, but there are more than 100 different forms. In 2012, more than 51 million people reported that they had been diagnosed with some form of arthritis, according to the National Health Interview Survey.