Finger length linked to osteoarthritis risk

12.00.00am UTC (GMT +0000) Tue 8th Jan 2008

New research has suggested that having uncommonly long ring fingers could indicate a person is at greater risk of developing osteoarthritis (OA) of the knee. A study of more than 2,000 people, published in the journal Arthritis and Rheumatism, suggests that people whose index finger is shorter than their ring finger are up to twice as likely to suffer from OA.

Previous research has established that index to ring finger length ratios (referred to as 2D:4D) have hormonal connections, including prenatal testosterone levels, lower oestrogen concentrations and higher sperm counts.

In the latest study, a team from Nottingham University looked at whether the ratio was linked to OA risks. In the trial, 2,049 people were recruited from orthopaedic surgery lists and a rheumatology clinic in Nottingham. All had clinically significant symptomatic OA of the knees or hips.

Another 1,123 individuals with no radiographic evidence of hip or knee OA were used as controls. Researchers used radiographs to assess the 2D:4D length ratio in all cases. It was discovered that people whose index finger was shorter than their ring finger were more likely to have OA.

"The 2D:4D length ratio appears to be a new risk factor for the development of OA," concludes the study's leading researcher, Professor Mike Doherty."Specifically, women with the 'male' pattern of 2D:4D length ratio - that is, ring finger relatively longer than the index finger - are more likely to develop knee OA." However, the team said that the "underlying mechanism of the risk is unclear."

An Arthritis Research Campaign spokeswoman said the results were fascinating but that more research was required