Is technology injuring our kids?

Mitali Perkins' 13-year-old twins, James and Timothy, are avid gamers who own three computers, two Sony PlayStations, a Nintendo GameCube and a Microsoft Xbox. Physically, they're fit, with one oddity -- the boys can bend their thumbs all the way back to their forearms, and they constantly stretch and crack their knuckles with ease. For tasks like ringing a doorbell, dialling a phone number and changing the remote, they use their thumbs.

"The word 'arthritis' comes to mind," Perkins wrote in an email to CNET.co.uk's sister site, News.com.

The Perkins boys' flexi-thumbs could be genetic -- or they could be the physical adaptation of two game fanatics, just like big thighs are to bicyclists and strong shoulders are to swimmers. Whatever the case, the prolonged exposure to technology by a generation of kids has doctors, researchers and physical therapists expecting a rash of new repetitive stress injuries in the coming years.

A study from 2000 in Australia on the effects of laptops in schools showed that 60 per cent of students aged 10 to 17 complained of neck and back discomfort while using the PC.

"Not since the development of a written language has the task performed by children and adults changed so dramatically," according to the report from the International Ergonomics Association.

Unfortunately, conclusive research on the subject of computer ergonomics for kids has been lacking. But researchers are concerned nonetheless.

"The exposure to ergonomic risk hazards for children is expected to be higher than it would be for adults because of the sheer amount of time that they're on computers at home and at school," said Ken Harwood, director of the practice department at the American Physical Therapy Association.

"So we expect to be seeing more diagnoses of repetitive stress injuries (RSI) in kids in the upcoming years as these kids start to develop, but we lack the evidence that supports it," said Harwood, who's also a physical therapist and certified industrial ergonomic specialist.

Repetitive stress as young as eight
Some physical therapists and paediatricians are already citing cases of RSI in children as young as eight years old. Kids complain of headaches, neck problems and backaches, and when paediatricians can't identify the source, they'll send the child to a physical therapist.

"We see so many more middle school children with neck [pain] and backaches," said Doreen Frank, a physical therapist. "When we evaluate them and find there's been no trauma or no new activity, it narrows down to the fact that they sit for way too long and then they're on the computer way too long," Frank said.

Many adults who have witnessed kids swapping hobbies like football or dance for instant messaging and computer games aren't surprised by these concerns. But even athletic children can suffer as a result of prolonged states of sedentary computer slump without break that strain developing muscles and joints. In the last five years, Frank said, at least 5 per cent of her patients have been middle school children with neck and back pain, some as young as eight.

Alan Hedge, a professor of ergonomics at Cornell University, said it takes an average of five to ten years for people with poor computer habits to develop RSI problems. At that rate, kids in high school or college today might be primed for stress injuries while in the workplace -- and it would likely be recorded as a work-related injury. Because there's no national database tracking child ergonomics issues in schools, there would be no way for researchers to understand the scope of the effects, he said.

Still, there's hope that digital kids could adapt to their heavy computer use.

A theory called the 'Healthy Worker Effect' supposes that when someone performs a repetitive task for a long time, like lifting heavy boxes or surfing the Internet, the person can develop a resistance to problems associated with the activity. The effect may be developmental, according to Harwood, in that children could develop a body structure to handle more ergonomic stress than they would have if they started the task as an adult.