Lady McCartney is dancing with Latin dancer Jonathan Roberts

Producers held back the former model's routine until almost the end of the show, but she fared well with judges.

The 39-year-old, who has an artificial leg, was told by judge Bruno Tonioli: "You've got more guts than Rambo."

Lady McCartney split from former Beatle Sir Paul McCartney last May. The couple are in the process of getting divorced.

The former model lost her left leg below the knee when she was hit by a police motorcycle in 1993.

She told viewers she had joined the competition to show it was possible to overcome disability.

"A little kid sitting there who's just lost a limb, I hope they're gonna go: 'Oh, I can.'"

Sixth place

But it was not Lady McCartney's leg-work that drew criticism from the US TV show's panel of judges.

"You've got to watch your arms," choreographer Carrie Ann Inaba told her.

"When you're worried about your leg and your weight on your leg, your shoulders get really tense."

"I'm just glad I didn't fall over," said Lady McCartney of her performance, which scored 18 out of a possible 30.

Lady McCartney and dance partner Jonathan Roberts finished sixth out of 11, but she was upbeat about the result. "I thought I'd be the lowest so I'm pleased," she said.

Former *NSync singer Joey Fatone took first place with a jokey cha cha cha.