Liza Minnelli says having knee replacement surgery was a “traumatic” experience.

The legendary entertainer underwent the painful procedure earlier this year but is now back working and is delighted by how quickly she has regained her strength and energy.

She said: “I'm running around like a wild woman. You know it's quite traumatic, having a full knee replacement. But I'm back in dance class every day, plus I go to the trainer. The strength is getting really great, and I'm touring all over the place. My god, I'm everywhere!"

Now that she is back on her feet, the 64-year-old star is looking forward to getting the chance to see ‘Poker Face’ singer Lady Gaga perform in concert.

She told website PopEater: "I love Lady Gaga! I haven't had a chance to see her live yet, but I like that she goes for it. I like somebody who says, 'Wait a minute, watch this.' And that's what she does."

Liza’s spokesperson revealed at the beginning of this year that she was to undergo the surgery after a lifetime of performing had taken its toll on her body, but insisted the procedure wasn’t serious.

The spokesperson said at the time: "Liza, who has been dancing on stage since she was a teenager, is 63. She is expected to make a full recovery."