Swinging games

My father likes to play quite roughly with my one-year-old, and their favorite game is when Grandpa swings baby through the air by his arms. I just worry about all the force on those little joints. Am I being an overprotective mother?

This game actually does have the risk of dislocated shoulders. The same applies to the game where the child walks between two adults and they swing the child along. Dislocated shoulders are painful but easy to fix.