Ok, it's been 25 - 30 years, so I'll share admit:
When my kids were little, they had Gameboys. It had 'something' that made it heavier, I think battery related, just can't remember.
It was one of the first Game Boys, so it didn't save how far a person got in a game, the next time you just had to start over.
I was so determined to finish that Tetris game I got a sore wrist. I can't remember what was sore, but the DO (doctor of Osteopathy) gave me a steroid injection.
Took care of the problem, no side effects, never returned (When it was available, we got a 'thing' that enabled us to play Game Boy games on the tv.)