After nearly 20 years at the top of her game, it appears the passing of time may at last have caught up with Kate Moss.

The supermodel arrived at Sir Paul McCartney's 65th birthday party in a dress that revealed a pair of distinctly bony knees.

She was wearing a cream Old Hollywood-style garment, slashed to the thigh, for the the party.

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Kate Moss, arriving at Sir Paul McCartney's 65th birthday party, wore a dress that revealed her rather knobbly knees

The dress is clearly a favourite, since it was worn by Miss Moss when she celebrated her own birthday in January. However, it was not very forgiving when she climbed from her car, exposing legs that appeared bony and sinewy.

It has been rumoured in recent months that her contract with cosmetics house Rimmel is under threat because the 33-year-old model's partying lifestyle has taken its toll on her appearance.

Prominent veins were also visible on her hands as she clutched a fuchshia-wrapped birthday present for Sir Paul, father of her close friend, fashion designer Stella McCartney.

She arrived shortly before midnight and spent the early hours of the party on Tuesday night drinking Singapore Slings and Margarita cocktails with Elton John and David Furnish, writer and producer Richard Curtis and Jools Holland.

The party was organised by Stella, 35, and her sister Mary, 39, at Sir Paul's home in St John's Wood, North London. Others at the 1940s-themed event included Tracey Emin, photographer David Bailey and former Beatles producer Sir George Martin.