It appeared his right foot got stuck in the turf while planting on his right foot and cutting left. He wasn't touched on the play.
He didn't bear weight on his right leg walking off the field, and didn't return to play.
Peyton Manning should appropriately "feel sick".
Between 72 percent and 95 percent of ACL injuries are "noncontact", occurring in athletes who haven't collided with a person or taken a blow to the knee.
If there was a pop and immediate swelling, then there is an 85 percent chance his ACL ruptured, 10 percent chance he dislocated his patella, and a five percent chance another type of sprain occurred such as an MCL sprain or possibly a hyperextension injury.
The ACL usually ruptures completely, though partial tears (or sprains) can occur.
A sprain of magnitude to require an athlete to be helped off the field usually involves a bone bruise or contusion when the tibia (shin bone) impacts or collides with the femur (thigh bone) producing microfractures. These aren't visible on x-ray, but light up like a light bulb on MRI.
What’s the bad news?
There's no rehab for a bone bruise. Time only; lots of it. Six weeks minimum.
A patella dislocation is usually repaired surgically in the NFL. End of season.
And the ACL? We all know the news on that one.
Marc Silberman, M.D.
New Jersey Sports Medicine and Performance Center