Osteoarthritis is the most common of all disorders of the joints. The first symptoms appear usually in the 4th decade, and 60 to 70% of people are affected by the 7th decade.
Early on, more women than men are affected by osteoarthritis, but this discrepancy is less marked in the elderly. There is a strong hereditary tendency, especially in the case of hand joints in women. There is evidence that genes coding for collagen components within cartilage may be abnormal, explaining the family clustering of this condition.
The earlier the onset and the greater the genetic factors, the greater the risks of developing osteoarthritis are. Patients with both parents affected will most certainly develop osteoarthritis.
Obesity is an independent risk factor for osteoarthritis of the knee, and may predict development of the condition 30 years later. Although mechanical loading is the obvious explanation for this link, other metabolic abnormalities associated with obesity may be involved.
Joint hypermobility (joints that stretch further than normal) is also an independent risk for the development of osteoarthritis. Some patients may have extreme hypermobility, leading to recurrent stress injuries and early osteoarthritis of weight-bearing joints.
Obesity linked to osteoarthritis
Symptoms of osteoarthritis
Treatment of osteoarthritis
Reviewed by Dr Ingrid Louw, MBChB, MMed (Int), rheumatologist/physician, (private practice), June 2011