Rihanna cancelled her Grammy performance due to bronchitis. She actually arrived at the venue of the awards, the Staples Center, but did not walk the red carpet. She went straight to rehearsals but left. It was reported that a doctor on site recommended that she quit the performance because it could permanently damage her vocal cords. Rihanna reps said she really wanted to perform but reluctantly decided she had to listen to her doctors. 
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