Christina Aguilera has a different story when it comes to celebrity stories, but she is also counted among the celebrities who have undergone plastic surgery. If you look at the before and after image above you can notice the nose job easily. Christina had reason for the nose job, she told that she had injury on her nose and Doctor wanted her to have surgery .After rhinoplasty her nose is smaller and less bulbous in tip and thinner as well.
Apart from Rhinoplasty you might also want to know that she had a breast augmentation/ implants (breast enlargement) as well. Christina Aguilera showed drastic increase in her breasts at very tender age. After delivery of her son in 2008 Christina got rid of her big breasts and went for smaller ones.
In 2010, during promotion of one of her movie in Japan Christina applauded her fans by raising her arm and one can easily notice scar under her arm (pic below). Scar under her arm was result of breast augmentation as Doctors implant through armpit so as to not leave any scar on breasts.