Britney Spears Injures Knee

David Letterman joked during his Late Show monologue on Thursday night, “Did you hear about Britney Spears? She was shooting a music video and during the filming she injured her knee. So let this be a lesson to you kids out there, I know it looks easy, but lip-synching can be dangerous. And isn’t this the second time she’s injured her knee in the last several months? She’s having a lot of trouble, she puts on a very athletic act and she damages her knees but don’t worry, she went to the best surgeon in the country. I believe it’s the same guy who worked on Monica. Same guy there who took care of her knees.”