Osteoarthritis Risk: Handy Finding
Finger Length Could Be a Clue About Your Osteoarthritis Odds
Jan. 3, 2008 -- Is your ring finger longer than your index finger? That may show a risk for knee osteoarthritis, especially in women, a British study shows.
Osteoarthritis is the most common type of arthritis. In osteoarthritis, the protective cartilage that cushions the ends of bones within joints gradually wears away. It can affect almost any joint in the body but commonly involves the weight-bearing joints: the knees, hips, and spine.
Osteoarthritis becomes more common with age and extra weight. Finger length may also be a risk factor, according to the new British study.
It's not about whether your fingers are long or short. Instead, it's about the ratio between the length of your index finger (the second finger, counting from the thumb) and your ring finger (the fourth finger).
Handful of Osteoarthritis Risk
The British study included more than 2,000 people with severe knee and/or hip osteoarthritis and more than 1,100 people without knee or hip osteoarthritis.
The researchers, based at England's University of Nottingham, eyeballed the length of participants' ring and index fingers, following up with hand X-rays for precise measurements.
The key finding: People whose index finger was shorter than their ring finger were about twice as likely to have knee osteoarthritis, compared with other participants.
That pattern was stronger for women than for men. Among women, those with an index finger shorter than their ring finger were three times more likely to have knee osteoarthritis.
The finding may also be true for hip osteoarthritis, but because most participants with hip arthritis also had knee osteoarthritis, it was hard for the researchers to confirm that.
Other osteoarthritis risk factors -- including age, sex, BMI (body mass index, which relates height to weight), previous joint injuries, and physical activity -- didn't explain the results.
Rheumatology professor Michael Doherty, MD, and colleagues aren't sure how to explain their findings. They note that men are more likely than women to have index fingers that are shorter than ring fingers, so hormonal factors may be involved, but that's not certain.
The study appears in January's edition of Arthritis & Rheumatism.