Kate Beckinsale's back injury was caused by a wardrobe mishap.

The 48-year-old star was hospitalised in Las Vegas last month and though it was speculated she'd hurt herself while shooting her movie Prisoner's Daughter, she's admitted nothing dramatic had happened.

Appearing on The Late Late Show with James Corden, the Underworld star said: "Having done eight or nine hundred action movies, I hurt myself putting on a pair of leggings in a hotel room. And I was in my hotel room putting on a pair of leggings and then it felt like a sort of guitar string snapped"

Kate  — who has 22-year-old daughter Lily with former partner Michael Sheen — admitted the pain was "worse" than when she gave birth and she was left unable to do "anything".

With few options to hand, the Van Helsing star had to stay lying down on the hotel room floor until the emergency services arrived to help.

She explained: "Eventually an ambulance came and they rolled out a sheet and picked me up in it, like a sort of a sausage and put me in a gurney."

Kate was rushed to hospital and given a cocktail of drugs to ease the pain, leading the teetotal actress to joke about how she found out what life would be like for her if she drank alcohol.

She joked: "'[I found out] what kind of a drunk I am. And so did everyone else. I'm not the ''do you know who I am, have you seen all my films'' type, which is a huge relief. So I'm really glad I'm not. But I am a ''everyone is trying to steal my f***ing ovaries' [type of drunk]."

Last month, Kate thanked fans for their support after it was revealed she was in hospital, but she didn't explain at the time what had happened.

She shared a photo from her hospital bed, which showed an IV attached to her arm, and wrote: "Feeling a lot better. Thank you so much for your kind messages and love x (sic)"

Watch Kate's interview on The Late Late Show here:


Photo: TPG News/Click Photos