By Kay Quinn, KSDK-TV, April 28, 2008

''Guitar Hero'' is among the most popular home video games out these days. It''s also led to a new classification of a common injury.

If you''ve ever had a sore shoulder, elbow or thumb after playing these games, chances are you''ve had what''s known as "Wii-itis" or "''Guitar Hero'' Thumb."

If you''ve ever played the game, you know how easy it is to get hooked. An hour or more later, you''re still strumming along to Black Sabbath or Joan Jett.

"My forearm''s gotten sore from playing ''Guitar Hero'' because you''ve got to move it really, really fast on harder songs," said Carlos Garcia, a ''Guitar Hero'' player.

Elizabeth Tauben is into playing the Wii as well.

"It''s not even a big motion," she said. "You''re barely moving, but you feel it the next day."

"These games are so enthralling that people will play for hours and hours and now realize that time went by and they wind up getting sore," said Dr. Mark Halstead, a sports medicine specialist at Barnes-Jewish Hospital and St. Louis Children''s Hospital.

That''s right. It''s not your imagination. Excessive ''Guitar Hero'' and Wii-playing can actually cause an overuse injury of the shoulder, elbow or hand, according to Halstead.

"Anything where you''re doing repetitive motion, whether it''s gripping onto an object, using your thumbs a lot, which all these video games are, yeah, you can get an overuse injury," said Dr. Halstead. "The common name is actually de Quervain''s tenosynovitis."

Just one of the hazards of having too much of this kind of fun: users typically feel the pain a day later.

"We like to out a whole bunch of catchy names on it," said Dr. Halstead. "So it''s been known as ''Space Invaders'' Thumb, Nintendonitis, now Wii-itis, which actually was described more from a shoulder problem than anything else. But it''s very similar to a kind of tennis elbow kind of thing."

In fact, it was reported in the prestigious New England Journal of Medicine. Some Acute Wii-itis was experienced by an otherwise healthy medical resident who woke up with intense pain in his shoulder. The diagnosis: tendonitis caused by playing too much Wii.

"If anybody''s doing repetitive stuff, whether it''s typing, doing stuff on the computer, shaking lots of hands like a lot of the political candidates, now they can get the same sort of thing," said Dr. Halstead.

Medical studies have shown this type of game playing is actually a form of exercise. Doctors believe it makes sense that your muscles and tendons would reflect intense game playing.

"You play for long enough, especially like bowling, or boxing, or baseball, or tennis, just from the swinging motion, your arm starts to get pretty sore," Tauben said.

"I get pain in my wrist up here from being tense on all the chords and stuff and shifting and back and forth," said Michelle Lange, another ''Guitar Hero'' player. "Also, my right arm, too. There''s really some, like, some fast passages you have to strum up and down, so my whole arm gets sore."

The treatment? Dr. Halstead said users can try this at home, but if you''re hooked on Wii and ''Guitar Hero,'' they might not like his advice.

"It''s a matter of just kind of cutting back on what you''re doing; icing, using a little anti-inflammatory for a few days, ibuprofen, motrin, things like that and usually that will settle down pretty quickly," Halstead said. "Usually it gets pretty painful that they''re going to want to stop doing that thing for a little bit, which is actually the thing that will get it better."

Once users rest, the pain should go away pretty quickly. But if users continue playing, those aches can stick around for a few days or even weeks.