Who Gets Osteoarthritis & Why?
Osteoarthritis is generally associated with age; x-rays show signs of the disease in more than half – and perhaps as many as 80% - of people aged 65 years and older.
Overall, 2-3% of the total adult population shows signs of OA, more often in women than in men.
Osteoarthritis typically develops due to instances of trauma across specific joints, especially those that are weight-bearing, such as the hips and knees. This trauma causes the joint cartilage and underlying bone to fail, and is considered primary OA.
Osteoarthritis may also develop without the presence or effects of heavy loads or trauma, specifically in cases where a person’s cartilage, bone, joints or supporting ligaments and muscles have experienced abnormal growth or conditions, due to a variety of causes. This is considered secondary OA – risk factors for secondary OA include:
- Bone/joint deformities or mechanical abnormalities
- Joint or bone injuries
- Long-term, repetitive joint use (ie. running, pounding, bending, etc)
The only sign that osteoarthritis may have a systemic (as opposed to direct, causal) factor is the increased presence of hand-related OA symptoms in obese people, despite the lack of correlation between any weight-bearing situations and use of the hand itself.