The mobile phone has brought a communications revolution to China, but doctors point out it is also causing a health problem -- with the thumb.

In particular, the popularity of text messaging -- known as "thumb culture" -- is being blamed for the new phenomenon.

Because of instant delivery and low charges, text messages have rapidly become one of the most popular means of communication among young people.

Figures show that in 2002, 90 billion text messages were sent through China Mobile and China Unicom, two major telecommunication service providers in China. That works out as an average of about 246 million messages per day. And the figure rose to 300 million a day during the SARS outbreak.

But young people are now paying for their messaging mania.

Tang Xiaoyan describes herself as a text message addict. Working in the Beijing branch of a Chengdu-based cultural communications firm, she has no relatives in Beijing and lives far from her friends, so text messages are her major entertainment.

Tang says her monthly expenditure on text messages ranges from 150 to 200 yuan (US$18.30 to $24.40).

However, Tang said her thumbs had become sore. "It's getting worse day by day," she said.

A doctor told her she wrote too many text messages and her tendons were injured.

Wang Heping, a senior doctor with Renmin Hospital of Northwest China's Gansu Province, said: "I have diagnosed four cases of tenosynovitis this year, and I believe there are more people who haven't seen a doctor."

Thumbs might be hurt by pressing the phone keypad too much, too quickly and in a very small area, Wang said.

"To keep your thumbs healthy, the best way is to write less messages and do more physical exercise," he said.

(Xinhua News Agency July 22, 2003)