Possible Causes of Osteoarthritis

According to the American College of Rheumatology osteoarthritis most often affects middle-aged and older people. However the average age of people that responded to our survey was 35-45 and several were diagnosed in their teen years. That made me wonder what leads to OA in younger people? I soon found out that there are many factors that lead to the development of osteoarthritis.

Although OA is common worldwide certain ethnic groups have a higher risks of developing OA. For instance, Caucasians have a higher risk than Asians. Osteoarthritis in the hips is very common in the US, but the risk is lower in Asia or some Middle Eastern countries. So simply being Caucasian can increase your chance of developing OA.

Gender also plays an important role. Before age 45, osteoarthritis occurs more frequently in males. After age 55, it develops more often in females. In one Dutch study, at the maximum age of osteoarthritis prevalence, nearly 30% of women and 8.5% of men showed signs of osteoarthritis in the knee. Why? The cause for this gender difference in the higher rate of arthritic knees in women may be high-heeled shoes. One study indicated that wearing shoes with 2 1/2-inch heels or higher forces women to alter the way they normally maintain balance and puts strain on the areas between the kneecap and thigh bone and on the inside of the knee joint. If you are still wearing high heels, get rid of them! The younger males developing OA has traditionally been blamed on high impact sports, if this is the case than those statistics should be changing soon. Females seem to be playing high impact sports just as often as males now a days.

Obesity is another factor. Knees, for example, sustain an impact three to five times the body weight when descending stairs. If you weigh 200 pounds, that is 600-1000 pounds banging on those knees. If you are obese, any loss of weight will be beneficial. A loss of only five pounds can eliminate at 15-25 pounds of stressful impact on the knees.

Genetics appear to play an important role in the development of OA. One study found that a genetic factor may be involved in 30% of people with osteoarthritis in the hand and 65% of those with osteoarthritis in the knees. In another study, researchers reported a higher correlation of osteoarthritisbetween parents and children or between siblings than between husbands and wives. Researchers have also found a genetic defect that seems to promote a breakdown of the cartilage’s protective structure.

A number of people have anatomical abnormalities, such as mismatched surfaces on the joints, which could be damaged over time by abnormal stress. Legs of unequal length or skewed feet can cause jerky movement and may induce osteoarthritis.

Osteoarthritis can sometimes develop after trauma to or near a joint. Repeated stressful motions can also contribute to deterioration of cartilage as can muscle weakness. Weak muscles don?t support the joint properly and can lead to uneven wear. Other forms of arthritis can lead to OA. For instance, if all of us with RA were to be cured tomorrow, most would have OA as a result of the inflammation and erosion of RA.

As more and more baby boomers develop OA, more and more research will be done to find out the causes, potential treatments and ways to prevent it. The next few years will likely produce a plethora of information regarding osteoarthritis.

Well-Connected Report-Osteoarthritis, Copyright ? Nidus Information Services, Inc. 1999
American College of Rheumatology
Understanding Arthritis, The Arthritis Foundation, ? 1984
Arthritis Foundation
The National Institute of Arthritis and Musculoskeletal diseases, Handout On Health-Osteoarthritis