Trivia: Amy Adams had a small role in the Smallville TV show in its first season as a girl affected by Kryptonite.
Trivia: Mackenzie Gray plays Jax-Ur in the film, and also played a Lex Luthor clone in the Smallville TV show.
Trivia: When the pod launches to shoot General Zod's ship from the plane, one of the people in the plane gets blasted out of the back and lets out a quite noticeable Wilhelm scream. (01:58:05)
Trivia: The Sullivan truck and tractor repair shop is a reference to Chloe Sullivan from the Smallville TV show.
Trivia: Tahmoh Penikett, who plays Zed Eubanks, appeared in the TV series "Smallville" as two different characters.
Trivia: Chad Krowchuk, who played Glen Woodburn and would reprise his role in "Batman v Superman", played a character, Wendel Johnson, in the TV series "Smallville."
Trivia: Henry Cavill was considered to play the role of Superman in Superman Returns.
Trivia: While Zod and Superman are fighting on the street and Superman jumps on the Lexcorp truck tank, there is a sign of a smiling yellow face. That's the Comedian's badge from the graphic novel Watchmen (played by Jeffrey Dean Morgan, who plays Thomas Wayne in the DCU). Zack Snyder also directed the movie adaptation.
Trivia: The Batman logo is hidden in Jor-el's armour beneath his "S".
Answer: Kryptonians aren't invulnerable. It just takes a lot to hurt one after he has been charged by our yellow sun. There are several beings who are strong enough to break a Kryptonian's bones. Doomsday, Darkseid, etc. Since both are roughly equal in strength on Earth, its no different than one human breaking another's neck.
Grumpy Scot