Osteoarthritis is the most common form of arthritis in the United States. This painful disease affects an estimated 21 million adults. This ailment begins with the breakdown of joint cartilage and is most common in the joints of the fingers, knees, hips and spine. It also can affect, but is less common in, the wrists, elbows, shoulders and ankles. The breakdown of cartilage associated with osteoarthritis results in the pain and stiffness in the affected joints.
The causes of osteoarthritis are not known, but when it occurs in the less commonly affected joints, it is typically associated with direct injury or unusual stress to that joint. Many people who have strenuous jobs requiring constant bending of the knees, repetitive bending or squatting have a high incidence rate of osteoarthritis.
The symptoms of steoarthritis are steady or intermittent joint pain, stiffness after periods of inactivity, tenderness or swelling in the joints and a crunching or rubbing sound when the joint is used. It normally progresses slowly, and early in the disease the joints may ache only after use.
Symptoms normally appear first in the fingers, for which the thumb joint is commonly affected. Finger-related osteoarthritis is typically genetic. Knees also show early symptoms of osteoarthritis as these joints typically bear heavy weight. The symptoms may show up any time a patient has to bend the knee, such as getting up from a chair or climbing a staircase. Hip pain is also common early in the disease and can cause difficulty moving, bending and walking. When osteoarthritis affects the spine, it can cause stiffness in the back and neck, and numbness in the arms and legs.
As the disease progresses, cartilage in the joints starts to break down. When this happens, the ends of the bones thicken and the joints may lose their normal shape. That is why it is not uncommon for those who suffer from osteoarthritis to have knobs on the joints. In the fingers, the knobs that appear on the end joints are called Heberden's nodes, and the ones on the middle joints are called Bouchard's nodes. As the cartilage breaks down further, the bones may actually touch during movement. This rubbing together can cause great pain.
The inflammation associated with osteoarthritis causes the release of prostaglandins, a group of potent hormone-like substances produced in human tissue to mediate a wide range of physiological functions, including inflammation. Prostaglandins are thought to be the primary cause for the pain associated with the disease. In the advanced stages, where the bones rub together, prostaglandin production is greatly amplified.
Prostaglandin production is controlled by a group of enzymes called cyclooxygenase or COX. There are two known types of COX enzymes: COX-1 and COX-2. The COX-2 enzymes are thought to be the most closely associated with pain. Thus, many pain relievers have been developed to block the effects of COX-2 enzymes. However, research indicates that blocking only one type of COX enzyme can create a very dangerous imbalance. This imbalance presumably is what has lead to heart attacks, strokes, blood clots, and other cardiovascular side effects linked to Vioxx use. (Read in detail about COX enzymes.)
Drugs such as Vioxx, used to relieve the pain of arthritis, are designed to block the production of prostaglandins by inhibiting COX-2 enzymes. In September 2004, Vioxx was recalled by Merck because of side effects related to elevated incidence of heart attacks, stroke and blood clots. If you are taking Vioxx to treat osteoarthritis, you should immediately consult your physician. In addition, you should contact an experienced Vioxx personal injury lawyer to discuss your case and determine if compensation might be available. In many cases, Vioxx-related cardiovascular diseases require extensive, costly therapy, which can wreak havoc in victims' family lives. This is why many Vioxx injury lawyers often recommend that their clients also consult with attorneys who practice as family attorneys and divorce lawyers. In addition, some Vioxx victims require the help of a skilled auto accident attorney.
Other best-selling COX-2 inhibitors, Celebrex and Bextra, have also been found to increase the risk of heart attack. Pfizer, the manufacturer of Celebrex and Bextra, has not pulled the drugs from the market, but has stopped direct marketing to consumers.
The following factors typically increase the risk for development of osteoarthritis:
- Age: Persons over 65 years of age or more likely to have this disease.
- Gender (Female): Before age 45, osteoarthritis is more common in men; after this age it is more common in women. Women typically have the first symptoms in the hands and fingers.
- Joint Injury or Overuse: Any injury or overuse that would have affected the integrity of the joint, the integrity of the cartilage or caused the joint to be overly stressed.
- Obesity: Since being overweight places greater stress on the joints, obesity is a common factor associated with the development of osteoarthritis.
- Genetics: There are some hereditary defects of collagen, which is a primary component of the cartilage that can lead to deterioration of the cartilage and ultimately to steoarthritis.