A doctor in Thailand has warned that a growing number of youngsters, especially university students were suffering from "trigger finger" and other related problems due to the time they spend on their smartphones.

A DOCTOR in Thailand has warned that a growing number of youngsters, especially university students were suffering from "trigger finger" and other related problems due to the time they spend on their smartphones.

Chutiphon Thammachari, a physiotherapist at Mahidol University's Faculty of Physical Therapy, said those who use phones for prolonged periods, bending their necks and elbows and tapping fingers on screens to text long messages were at risk.

"This can result in fingers, wrists, shoulders and even necks becoming "locked" in one position, with associated pain.

Chutiphon Thammachari, a physiotherapist at Mahidol University's Faculty of Physical Therapy, said they found that the ages of our patients are getting lower, since students are spending more hours on smartphones and computers," she said.

In a growing trend over the past two years, more young patients -- mostly students aged between 20 and 22 -- are seeking treatments for muscle and tendon inflammation at the university's Physical Therapy Centre.

According to Bangkok Post, trigger finger (stenosing tenosynovitis) is a disorder of the tendons characterised by stiffness and a sensation of locking when a finger is straightened, she said.

Meanwhile, the associated "texting thumb", or De Quervain's syndrome, is caused by inflammation of tendons controlling the thumb.

Frequent and prolonged use also puts phone users at risk of painful "tennis elbow", when tendons are overloaded by the need to hold the joint in a bent position.

The same problem can afflict tendons in the shoulder and neck.

To avoid these painful conditions, users should change the way they operate their devices, Chutiphon said.