George Pimentel / WireImage 1 / 5
George Pimentel / WireImage 1 / 5

Natalie Portman says she dislocated a rib on the set of her new movie, "Black Swan," and that producers didn't have an on-site medic.

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"I injured a rib," she said Monday night in an appearance on the "Late Show With David Letterman." "I, like, dislocated a rib. It sort of went under another one -- when you get lifted -- it just sort of went under.

"It's funny because when I got injured, I called the producer. I was like, 'Could you get the medic? I need an ice pack or something right now,' and he was like, 'Oh, we don't have a medic because it's super low-budget.' I have been working for, like, 20 years (and) I don't even think that's legal. I was like, before you take away a medic, take away my trailer -- and the next day I didn't have a trailer, I swear to God!"

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Portman, 29, plays a ballerina in the Darren Aronofsky film and has spent up to eight hours a day in dance training to make her portrayal believable.

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