A look at key players for each NFC North team who are coming back from injuries:
Chicago Bears: Place-kicker Robbie Gould needed offseason surgery after rupturing a semitendinosus tendon in Week 15 and still hadn't been cleared to kick 13 weeks after. All indications are that Gould will be ready for training camp and should once again be the Bears' place-kicker in 2013. Since he entered the NFL in 2005, Gould has the seventh-best percentage of conversions (85.6) among place-kickers with at least 100 attempts, an especially notable standing considering the typical kicking conditions at Soldier Field. With all of the other changes in the organization this offseason, the Bears need the reliability that Gould provides.
Detroit Lions: Safety Louis Delmas managed to play only 41.97 percent of the Lions' defensive snaps last season because of a knee injury that required surgery in training camp. Delmas' knees have been a bothersome issue for most of his career, and there has never been any doubt about the difference in the Lions' defense when he is in and out of the lineup. The team took a cautious approach to re-signing him in free agency, offering a modest deal that would pay him six-figure incentives for every game he plays if he manages to exceed his playing time from last season. The Lions signed free agent Glover Quin as well, but they need Delmas on the field.
Green Bay Packers: Two players who missed the 2012 season because of 2011 injuries could be in position to help the Packers in 2013. Offensive lineman Derek Sherrod had a second surgery this winter to finish repairing a leg he fractured in multiple places, and the Packers have hopes that he can compete for their open right tackle job. Tight end Andrew Quarless, meanwhile, is trying to get back on the field after blowing out his knee in December 2011. When healthy, Quarless might be the Packers' most balanced tight end in terms of receiving and blocking. Jermichael Finley is the team's top tight end, but Quarless could provide important versatility to the position.
Minnesota Vikings: Receiver Jerome Simpson's disappointing season in 2012 -- he caught 26 passes and no touchdowns in 12 games -- has been attributed in part to a mysterious back injury that decreased the explosiveness in his legs. The Vikings are hoping Simpson can regain the running and leaping abilities that helped him catch 50 passes for the Cincinnati Bengals in 2011. Although they signed Greg Jennings, the Vikings still have a need for a veteran receiver who can get downfield -- especially while rookie Cordarrelle Patterson is given time to develop. Simpson is the team's best option there.