Celebrities who've had plastic surgery

27 of 36: Kara DioGuardi said on Howard Stern's Sirius XM radio show in 2011 that she had liposuction on her knees. Pictured: Kara DioGuardi appears in a bikini at the finale of 'American Idol's ninth season in 2010, which marked her second and final year as a judge.

It is unclear whether Kara DioGuardi underwent cosmetic procedures prior to appearing on 'American Idol' in 2010. ( Photo / FOX)