It is the largest joint in the human body. The knee is a modified hinge joint, which permits flexion and extension as well as slight internal and external rotation. The knee is vulnerable to injury and to the development of osteoarthritis.
Many knee problems are a result of the aging process and continual wear and stress on the knee joint (i.e., arthritis). Other knee problems are a result of an injury or a sudden movement that strains the knee
When you experience pain in your knee, it may be comforting to know you’re not alone. This is an extremely common complaint. Because of that many people ignore it, hoping the discomfort will fade on its own. In many cases, it does. But waiting too long to go to the doctor can lead to long-term damage if you have a serious injury or condition. That’s why you should seek medical attention if you experience any of the following signs:
Arthritis: Although there are many different kinds of this disease are characterized by joint inflammation, the two that most commonly affect knees are osteoarthritis and rheumatoid arthritis.