It's happening around TV sets in more than 10 million households across the US.

An interactive video game is connecting grandparents with their grandchildren and providing a great workout.

But is there such a thing as too much Wii?

Doctors say “yes.”

Orthopedic specialists call it Wii-itis.

"Sort of sparked a whole other type of injury that we've actually never even seen before," says Dr. John Sperling, orthopedic surgeon at the Mayo Clinic in Rochester, MN…"For most people, they would play maybe an hour of tennis and stop after that, but with the Wii, there's an unlimited amount of time you can play, and there's really not the same feedback of getting tired playing a sport," says Dr. Sperling.

WNDU by Maureen McFadden, 10/1/09

Tags: Orthopedics, Orthopedics, Wii