Britney Spears displays her gruesome knee injury on Instagram

Britney Spears displayed her gruesome knee injury in a new video after hitting back at her ex-husband Kevin Federline. The superstar, 43, shared another dancing video on her Instagram account and could be seen with a huge bandage wrapped around her knee. Explaining her injury earlier this month , Britney said that she 'fell down the stairs' and her leg 'snaps out now and then' adding she's 'not sure if it's broken.'