What is this riddle? It's the one thing that virtually no team can solve: injuries. The Packers have been riddled by them (think Jermichael Finley, Ryan Grant, Nick Barnett over the course of the season). The Bears don't have any.
At Football Outsiders, we track injuries in a variety of ways. One is Starter Games Lost, or SGL. The idea is simple: How many times did a player who would have been in the starting lineup if healthy miss a game? By this definition, a starter can be a player who was penciled into the starting lineup before the season but suffered an injury, like Elvis Dumervil of the Denver Broncos. It can also be a player who became a starter once the player ahead of him in the lineup was injured, only to become injured himself. An example would be Packers safety Morgan Burnett, who took over as the starter for an injured Atari Bigby, only to tear his ACL and force the Packers into starting third-stringer Charlie Peprah.