Vick's injury explained further

According to Eagles coach Andy Reid, quarterback Michael Vick has a crack in his rib cartilage, and running back LeSean McCoy has a crack in a rib bone.

Brian Sennett, chief of sports medicine at the University of Pennsylvania, said the injuries are similar but different.

"The last one inch of the distance from the rib to breast bone is cartilage," Sennett said. "It is different from the kind you'd have in a knee. It looks like a rib, but it's made of a cartilage material that allows you to have flexibility so your rib cage can get bigger. These structures look like ribs but are a rubbery material."

When you injure your chest, one of three things can happen, Sennett said. You can break a rib, injure the junction of the rib and the cartilage, or injure the cartilage, which is what Vick did.

"His is to the cartilage," Sennett said of Vick, "and so you would manage it similar to a broken rib. Usually the player is out somewhere between two to four weeks."

The Eagles have not detailed the exact location or severity of either injury.