The 30-year-old singer sizzled on the red carpet in a little black dress, but her strappy heels drew attention to a big patch of dry scaly skin on her ankle, reported Sun online.
Spears is busy these days judging and mentoring acts on the US version of the TV talent show.
In September, it was reported that Spears was battling skin condition psoriasis, and that it only flares up when she is under extreme pressure.