The star is forced to axe tour dates after a dance routine goes a bit wrong...
BRITNEY SPEARS has pulled out of two dates on her US tour after injuring her knee.
The superstar was performing in Moline, Illinois when she injured her knee during a dance routine in the encore. The performance was cut short and the singer came out to apologies
As a result, shows in Chicago and Detroit have also been pulled.
The dates will be rescheduled for April.