Osteoarthritis of knee occurs due to the breakdown and loss of cartilage in one or more joints. The cartilage which is found between bones is a protein substance that acts as a cushion preventing friction. As we age, the cartilage deteriorates, becomes rough and eventually it wears down completely. This will result in bones rubbing against each other. Primary osteoarthritis is that which the cause is not known while secondary osteoarthritis is when the cause of the condition is known. Aging is commonly associated with primary osteoarthritis in which case water in the cartilage increases while the protein degenerates.
The cartilage will start to degenerate by forming small crevasses. If the worn out joint is continuously used, irritation and inflammation of the cartilage occurs leading to swelling and joint pain. New bone outgrowths may develop resulting in limited joint mobility. Secondary osteoarthritis of knee develops as a result of another disease. It can be caused by diabetes, gout, obesity, hormone disorders surgery or trauma to the knee joint. Obesity leads to the knees carrying more body weight placing stress on the joints. People with abnormally formed joints are more prone to mechanical wear which results in cartilage loss.
There are various symptoms associated with osteoarthritis of knee. The most prominent is pain in the joints during or after movement, stiffness especially in the morning or following an extensive period without activity. When you apply pressure to the joint you may feel some tenderness and you may lose some flexibility; inability to move the knee joint in certain directions. Bone spurs may develop around the joint and you may feel hard lumps and grating sensations when the joint is in use. As the cartilage degenerates, the knee joints can get deformed leading to a bowleg. Limping can occur in obese people and it can get worse as the cartilage degenerates.
To diagnose osteoarthritis, an X-ray may be done to indicate the loss of cartilage. Joint fluid analysis can be performed to see if gout is the cause of the pain. Since there is no cure for osteoarthritis of knee, treatment generally focuses on easing pain and inflammation. Painkillers reduce stiffness but will not repair the damaged joint. Non steroidal anti-inflammatory drugs have been known to reduce inflammation and relieve pain. Use of warm or cold packs on the knee is effective and eases pain significantly. If the knee joint is particularly painful, steroid injections are administered directly.
At times steroid injections may not work in which case hyaluronic acid injections are given. It restores temporarily the joint fluid thickness allowing lubrication and improved mobility. Exercise is important as it strengthens muscles around the knee joint and maintains and improves mobility. It helps in cases where weight reduction is needed such as obesity. Resting the knee joint will reduce stress, swelling and pain. Surgical procedures such as bone realignment focus on shifting body weight from the part of the knee that is worn out. Joint replacement is whereby the osteoarthritis of knee is replaced by metal or plastic devices known as prostheses.