Lions quarterback Matt Stafford suffered a dislocated knee cap on Sunday, according to an ESPN report. "He twisted his knee a little bit," coach Jim Schwartz told the Detroit Free-Press. "Obviously we'll have to do a lot of tests and those kind of things. He wasn't able to really get it warmed back up again, and we didn't want to put him back in the game." ESPN reported on Sunday night that Stafford's injury was a dislocated kneecap that popped back in while he was on the sideline. It's an injury that could cost him a game or two.