I have done this, nothing freaks you out more than looking down at your own knee, and seeing the knee cap on the side of it instead of in front of it. The key will be how much ligament damage to the knee cap there was, and if the knee cap itself is damaged. It hurts like hell though....I may cry. Mahomes ruled out with a knee injury. Spent only a few minutes in the X-ray room and was signaling to the trainers that it was the outside part of his right knee.
Edit: early rumor says a dislocated kneecap. Could be a few weeks, could be season-ending surgery. We will only know after an MRI which I would assume is scheduled for as early as humanly possible tomorrow morning