Employers are being warned they will end up with a painful bill if they do not do more to prevent their staff falling victim to workplace repetitive strain injuries.
A study last week by the Chartered Society of Physiotherapy warned that nearly half a million workers now have RSI.
The Forum of Private Business has now warned this is likely to have dire financial implications for businesses.
"Not only can RSI in staff lower productivity and profits, it can also be used as the basis for a costly claim by an employee for compensation against a firm," said FPB spokesman Rex Garratt.
Almost 450,000 UK workers have upper limb disorders, with health and social work employees most affected, said the Chartered Society of Physiotherapy.
Between 2003 and 2004 about 4.7 million work days were lost to RSI, as workers took an average 18 days sick leave.
The society called its findings "shocking" and urged firms to do more to protect workers.
The number of workers with RSI has increased by 52,000 over the past three years, it added.
RSI rates were increasing among workers in communications, transport and education.
