I read recently, possibly from a link on this board, that [some theropod dinosaur] had forelimbs that could not be rotated such that the “palms”, so to speak, faced the ground, that they for the most part, faced each other. So the big dinos hands were permanently oriented in a downward karate chop.
What I didn’t recall from the article was that whether that was universal or just common among the big guys.
I’'m pretty sure it is all theropods. The comment was specifically about the 'raptors in Jurassic Park being able to open doors, so it’s not just the big ones.