What is Knee Arthritis?
If you suffer from knee pain, it’s possible you have arthritis. Arthritis of the knee is a disease which wears away the cartilage between the femor (thigh bone) and the tibia (shin bone) causing the two bones to scrape against each other, raw bone on raw bone. When this happens, the joint becomes pitted, eroded and uneven. The result is pain, stiffness and instability. In some cases, motion of the leg may be greatly restricted. The two most common types of knee arthritis are osteoarthritis and rheumatoid arthritis.
Osteoarthritis is a progressive, degenerative disease, i.e. a condition where the joint over time loses cartilage etc., as explained above. Cartilage serves as insulation between the bones of the joint, and when the cartilage of the knee joint wears away due to osteoarthritis, the resulting pain and inflammation can be debilitating (weakening). Your chances of osteoarthritis of the knee increase with age; the condition most often affects middle-aged and older people. Osteoarthritis may first appear between the ages of 30 and 40, though symptoms may not be present in the early stages. By the age of 70 many people may have this type of knee arthritis.
The question of what causes osteoarthritis of the knee has not been answered. Prior knee injuries seem to increase the likelihood of osteoarthritis, but many people with knee arthritis have never had a serious knee injury. Osteoarthritis is the most common form of arthritis, and many people have a genetic predisposition to this chronic disease.
The primary symptoms of osteoarthritis are pain in the knee, swelling and stiffening of the knee joint. In the early stages of osteoarthritis the pain may be mainly associated with activity. As the cartilage wears away and the bones of the joint rub against each other, pain can become more severe and constant, interfering with regular daily activities and disrupting sleep.
In the early stages of osteoarthritis, treatment may involve several techniques. Behavioural and lifestyle changes including losing weight and changing routines to avoid painful situations can be very effective in relieving pain. Specific medications may provide relief from pain. Physical therapy may improve muscle strength and joint mobility, reducing the symptoms of osteoarthritis in the knee. Injections of fluids into the knee is also an option that may lubricate the knee and reduce the pain and swelling of the joint. Partial or total knee replacement surgery may be necessary as the disease progresses and daily functioning becomes more impaired.
Unlike osteoarthritis, rheumatoid knee arthritis involves inflammation of the lining of the joints known as the synovium. Though less common than osteoarthritis, rheumatoid arthritis is among the most debilitating of the over one hundred forms of arthritis. Rheumatoid arthritis usually develops in middle age, but may occur in the 20s and 30s.
The exact cause of rheumatoid arthritis is unknown. It’s possible that a virus or bacteria may trigger the disease in people with a genetic predisposition to rheumatoid arthritis. Rheumatoid arthritis is an autoimmune disease in which the tissue of the joint’s lining is attacked by the body’s immune system. It’s also possible that rheumatoid arthritis is caused by severe stress. The disease sometimes occurs after a life-changing event such as divorce, loss of a job or a severe injury.
The primary symptoms of rheumatoid arthritis include pain and swelling in the joints and difficulty moving. Other symptoms may include loss of appetite, fever, loss of energy, anaemia, and rheumatoid nodules (lumps of tissue under the skin). Apart from orthopaedic surgeons, rheumatologists specialise in the treatment of rheumatoid arthritis. If you think that you may have this condition, please speak to your general practitioner who may refer you to a specialist.
Treatment of rheumatoid arthritis usually involves medications, some of which are called "disease modifying" in that they change the way in which the disease progresses, and also pain killers. In severe cases, surgery may be indicated to replace the knee joint with an artificial joint. If you think you may have arthritis of the knee, contact your doctor for a complete evaluation and a discussion of the options available for treatment.