To be clear, Kristen Stewart was using crutches on the red carpet at the Oscars on Sunday night, and she appeared to be limping when she came out on stage to present. And backstage, according to the Associated Press, Anne Hathaway told her to "break a leg." 

It began when Hathaway, holding her Oscar for Best Supporting Actress, "ran into" Stewart: 

"Oh no!" Hathaway said.

"I know, I'm an idiot," Stewart replied. "But congratulations!"

When Hathaway asked if Stewart was going to use the crutches on stage, she explained her decision not to, to which Hathaway responded: "Well, break a leg," Hathaway said. "Oops."

How Hathaway

The injury as of yet has not been explained

Update: There is an explanation. Stewart cut her foot stepping on glass