Osteoarthritis of the Knee
Posted on Fri, Oct 01, 2010 @ 06:42 AM
A previous blog entry discussed osteoarthritis and exercise. Here is a more complete synopsis of knee osteoarthritis, its causes and treatments.
More than 20 million Americans suffer from osteoarthritis (OA), which is the number one cause of disability in the United States.
Even if you have knee osteoarthritis, there is hope to regain your active lifestyle and continue many of your favorite activities.
Knee osteoarthritis is a chronic disease. That means it will never get better and is likely to get worse over time. The knee pain and immobility are caused by wear and tear between the joints.
OA strikes three times as many women as men and most often occurs in people over 50. However, younger people who have been injured in sports or accidents can start having symptoms of knee pain in their 20s and 30s.
With OA, everyday activities may be painful or even impossible. Daily activities such as walking, driving, lifting, standing, bending, climbing stairs and exercising may cause extreme pain. It may even hurt to lay down, rest or sleep.
In addition to physical symptoms of knee pain, osteoarthritis takes an emotional toll. A National Council on the Aging survey sheds light on the way OA hampers peoples’ lives:
•OA sufferers reported gaining an average of 42 pounds since their diagnosis. This is partly due to patients’ inability to exercise as much as they would like to – a feeling expressed by 75 percent of OA sufferers.
•Loss of sleep, which can take a serious toll on relationships, productivity and public safety, is another side effect of OA. 37 percent of sufferers report losing two or more hours or sleep per night due to pain.
OA is a progressive disease. While early treatment of osteoarthritis can slow things down, affected knee joints continue to get worse. You may experience flare-ups as well as periods when you feel no symptoms of knee pain at all.
Healthy Knee 
The bones in your knee joint work like a hinge. They are covered by cartilage to keep them from rubbing together.
The space between the bones is filled with a thick, slippery liquid (joint fluid). Joint fluid acts like a shock absorber to cushion and lubricate your knee while walking, working or playing sports.
Mild to Moderate Osteoarthritis of the Knee
Your body’s joint fluid becomes less healthy and the cartilage begins to break down, leading to irritation and discomfort in the knee. Without healthy joint fluid, your knees become sore and swollen.
Progression to Severe Osteoarthritis of the Knee
As time passes, larger pieces of bone and cartilage can break off and float in the joint, causing pain and swelling. Large areas of cartilage can be completely worn away. Growths (bone spurs) may appear on the bone, leading to more irritation. In severe cases of osteoarthritis, your cartilage can be completely worn away. Your bones may actually rub together, causing pain and swelling.
Causes of Knee Osteoarthritis
Deterioration of articular cartilage is the main problem associated with knee osteoarthritis. The condition can be caused by:
•previous knee injury
•repetitive strain on the knee
•fractures, ligament tear, and meniscal injury which can affect alignment and promote wear and tear
•genetics which make some people more likely to develop knee osteoarthritis
•obesity
•problems with subchondral bone (the bone layer underneath cartilage)
Diagnosis of Knee Osteoarthritis
Medical history, physical examination, and x-rays are used to diagnose knee osteoarthritis. X-rays are very helpful, allowing the doctor to see evidence of joint space narrowing and rule out other causes of knee pain. If more detailed imaging is needed, an MRI may be ordered. Arthroscopic knee surgery is another way to view the condition of the knee. This may also be therapuetic.
Symptoms of Knee Osteoarthritis
Knee osteoarthritis typically develops gradually over a period of years. The primary symptoms associated with knee osteoarthritis include:
•pain (mild, moderate, or severe)
•stiffness
•limited range of motion in the knee
•localized swelling
Knee osteoarthritis pain is usually worse following activity, especially overuse of the affected knee. Stiffness can worsen after sitting for prolonged periods of time. As knee osteoarthritis progresses, symptoms generally become more severe. Pain can become continuous rather than only when weight-bearing.
Treatment of Knee Osteoarthritis
Knee osteoarthritis cannot be cured but there are treatments available to help manage the symptoms. Medications, starting with acetaminophen, can help manage and relieve pain. Some patients obtain better pain relief when using NSAIDs (nonsteroidal anti-inflammatory drugs) or Celebrex, the one remaining COX-2 selective inhibitor. There are opioid analgesic medications available for patients who need stronger pain relief.
Aside from medications, other treatments include:
•local intraarticular injections of steroids or viscosupplements
•exercise / physical therapy
•weight loss if overweight
•corticosteroid injections
•knee brace or support
•joint protection techniques - viscosupplementation injections
•heat and cold
•glucosamine and chondroitin sulfate
•arthoscopic exploration or total knee replacement
Getting diagnosed and treated while knee osteoarthritis is still in the early stages is most beneficial. If treated early, many people can effectively manage mild to moderate knee osteoarthritis. Have a discussion with your physician for appropriate options.
- Cote