Osteoarthritis, the most common form of arthritis, occurs when protective cartilage inside a joint wears down. This type of arthritis is unheard of in children and is rare in young adults, but often occurs in older people and people who are overweight. Because of this, osteoarthritis was long considered a natural product of aging and everyday wear and tear on joint cartilage.
However, many experts now believe the cause is much more complex. External factors, such as injuries, can set the stage for osteoarthritis, but how fast it progresses and how severe it becomes depends on a number of factors. Here are just a few factors that can increase your osteoarthritis risk.
- Genetic factors. Roughly half the risk of developing this condition can be attributed to your genes. Multiple genes are thought to be involved. What's more, the genes may have different effects depending on the joint affected and whether you're a man or a woman.
- Excess weight. Weight-bearing joints don't hold up well under the continued strain of extra pounds. One study found that overweight young adults were more likely to develop knee osteoarthritis than their slimmer counterparts. Losing excess weight can reduce the chance of developing osteoarthritis and make daily living much easier if you already have it.
- Joint injury. Injury to a joint, from either repeated use or trauma, may also trigger osteoarthritis. Because bones, joints, and muscles that are damaged rarely heal perfectly, joint injuries can create unusual mechanical stresses that lead to abnormal wear and tear.
- Other health issues. Osteoarthritis can develop in a joint already damaged by another disease, such as rheumatoid arthritis, infectious arthritis, or gout.
For more on keeping your joints healthy and ways to ease the pain caused by osteoarthritis, buy Living Well with Osteoarthritis, a Special Health Report from Harvard Medical School.