Total Joint Replacement Educational Series Part 16: Lifetime Risk of Knee Arthritis

BACKGROUND INFORMATION:

• Arthritis is one of the most common reasons for disability.
• Primary diagnosis for 430,000 hospital discharges
• $14 billion in hospital charges
• 12.1 % of Americans older than 60 years of age had symptomatic knee osteoarthritis (wear and tear arthritis/most common type)

Johnston County Osteoarthritis Study

This study analyzed the lifetime risk associated with developing osteoarthritis of the knee and hip.  The study was designed to be representative of a civilian English speaking black and white population 45 years or older.  Participants had to be physically and mentally capable of completing the study.

The lifetime risk of developing symptomatic osteoarthritis of the knee by 85-years-old was 44.7%.  There were no significant differences by race, sex and education, but obese participants had a significantly higher lifetime risk (60.5% compared with 30.2% and 46.9% among those who were normal weight and overweight, respectively).   In addition, patients with a history of knee injury had a higher lifetime risk of 56.8% compared to 42.3%. 

Overall, this study demonstrates the high lifetime risk of symptomatic osteoarthritis is likely due to the aging of the population and the alarming rates of obesity.  One in two people is at risk of developing symptomatic knee osteoarthritis and two out of three obese people.  The link of obesity to symptomatic osteoarthritis demonstrates yet another reason to educate the public about weight loss and weight management.  Osteoarthritis is associated with enormous health costs as well as disability.  By educating the public on how to manage or even eliminate obesity and weight issues, we have the potential of decreasing the public health burden of this condition.

Murphey, L.  "Lifetime Risk of Symptomatic Knee Arthritis."  Arthritis and Rheumatism 59 (2008): 1207-1213.