Once called the "invisible illness", RSI - otherwise known as non-specific arm pain - is believed to effect about 200,000 workers in the UK. It causes crippling pain and loss of strength, particularly in the wrists and hand, and is caused by highly repetitive movements, such as keyboard work.
Medical examination of RSI victims often fails to find a physical cause for the pain and disability, and it is still not recognised officially as an industrial injury.
Researchers from University College (UCL), part of London University, used a scanner to show that when RSI sufferers move their hands, the major nerve to the hand does not move out of the way of the associated tendons.
"It is important that the nerve moves, otherwise when people move their hands, the nerve gets pinched, compressed and irritated, causing pain," said Jane Greening, a physiotherapist and research fellow at UCL, and co-author of the study.
"The restricted nerve movement, seen in the people suffering from RSI, may not just be happening in the hand but also higher up in the arm, which would explain the diffuse symptoms associated with the condition," she said.
The study of seven RSI sufferers showed they had only 31 per cent of the normal nerve movement when they flexed their wrists.
The results also showed that it was irrelevant how long someone had had the condition - the reduction in nerve movement was the same. Those participating in the study had had RSI for anything from four months to seven years.
"Scans of the wrist and measuring the nerve movement could become a test for RSI and be a valuable tool for treating people," Ms Greening said.
The Chartered Society of Physiotherapy (CSP) welcomed a clinical test for the condition and said that is should be recognised as an industrial injury to ensure that sufferers have access to specialist treatment. Phil Gray, chief executive of CSP, said: "The weight of scientific evidence that [shows] RSI has a physical cause is such that it can not longer be dismissed by sceptics as a figment of the imagination.
"RSI must now be recognised as an industrial injury. With this official status, employers will be compelled to protect their staff."Reuse content