Parsi Teb Physical and Mental Health Journal 
Arthritis in the Knee
There are three different types of arthritis that can occur in your knees. The most common type is osteoarthritis, a progressive disease that slowly wears away joint cartilage. This type of arthritis is most likely to strike after middle age.
Rheumatoid arthritis is an inflammatory disease that can strike at any age.
When arthritis develops following an injury to the knee, it is called post-traumatic arthritis. It can occur years after a torn meniscus, injury to a ligament, or fracture of the knee.
Some types of arthritis can cause fatigue. Read about more symptoms of arthritis in the knee.
Gradual Increase in Pain
Arthritis pain can begin suddenly, but it is more likely to develop slowly. At first, you may notice pain in the morning or after you’ve been particularly inactive. Your knees may hurt when you climb stairs, stand up from a sitting position, or kneel. It may hurt just to go for a walk. In some cases, you may feel pain when you’re doing nothing more than sitting down. Some people with arthritis say that damp weather or other changes in weather can bring on pain. Knee pain that wakes you up from sleep can be a symptom of osteoarthritis.
Swelling or Tenderness
Buckling and Locking
Over time, the muscles in your knee may weaken and the entire joint structure can become unstable. The overall weakness in the knee can cause your knee to give way or buckle. The joint can also stick or lock up so you can’t bend it or straighten it out when you want to. You may find that these symptoms come and go for no apparent reason.
Cracking or Popping Sounds
You may feel a grinding sensation in your knees as you move. You might even hear cracking or popping sounds coming from your knees. These symptoms may be occurring because you’ve lost some of the smooth cartilage that helps with a smooth range of motion. If you have arthritis of the knee, the disconcerting noises and the grinding feeling are a result of rough surfaces and bone spurs rubbing over each other as you move your joints.
Poor Range of Motion
Arthritis can make it increasingly challenging for the knee joints to glide as they should, making previously simple movements difficult or impossible. You are most likely to notice a restricted range of motion when you climb stairs or participate in athletic activities. Osteoarthritis progressively wears away at cartilage. As arthritis worsens, it becomes harder for joints to function normally and it can become increasingly difficult to perform simple everyday tasks. In time, you may have trouble walking without the assistance of a cane or walker.
Loss of Joint Space
X-ray of the knees is an excellent diagnostic tool because it can clearly show the loss of joint space that causes those unsettling sounds and a poor range of motion. The space that normally allows freedom of movement is lost to bone spurs and other rough surfaces on the ends of bones. Bone spurs can occur when the cartilage is worn through, or from calcification. These spurs are a common sign of osteoarthritis.
Deformities of the Knee
As arthritis progresses, you may start to notice changes in the appearance of your knees. It can create a sunken appearance as muscles surrounding the knees thin and weaken. Your knees can start to point toward each other, creating a knock-kneed effect. They can also bend outward, creating a bow-legged look. Deformities of the knee can range from barely noticeable to quite severe.
