Week 13 saw a few of the league's top IDPs go down with injuries, while a few others were ruled out because of injury before games started.
The biggest injury is the hamstring ailment suffered by San Francisco's Patrick Willis, who is probably the league's top IDP in a year-to-year context. Fortunately, Willis isn't supposed to miss much time with the issue, though he'll be replaced in the starting lineup by Larry Grant this week, at least.
While they aren't as historically established as Willis, Indianapolis linebacker Pat Angerer and Tennessee cornerback Jason McCourty arguably have been just as valuable IDPs this season, and both left their respective games with injuries, too. Angerer is, fortunately, expected to play through the knee injury he suffered Sunday, though it's not clear whether McCourty will play this week after suffering a concussion against the Bills on Sunday.
In addition, Ray Lewis (turf toe), Desmond Bishop (calf), George Wilson (neck stinger), Von Miller (thumb) and Darian Stewart (concussion) missed their respective teams' games. Returns look very possible for Wilson, Miller and Stewart, all of whom have practiced this week, but things aren't as clear for Lewis and Bishop.
Colin McCarthy, LB, Titans
It's doubtful that any defender has seen his IDP stock improve as much as McCarthy has over the last three weeks. The rookie from Miami has 37 tackles (31 solo), one interception, two passes defensed and two forced fumbles the last four weeks. Barrett Ruud (groin) still had not practiced as of Thursday, meaning McCarthy has a good shot to start again Sunday. He would be an advised IDP start if that ends up being the case.
Elvis Dumervil, DE, Broncos
Now that he's finally healthy, Dumervil is looking like the player he was in 2009, when he finished the year with 17 sacks. Dumervil didn't get his first '11 sack until Week 9, but he has been making up for lost time by totaling 6.5 sacks in his last five games. It would be helpful if Von Miller (thumb) made a return to discourage double-teams, but Dumervil appears capable of producing even if he doesn't have much help around him.
Larry Grant, LB, Giants
With Patrick Willis (hamstring) likely out against Arizona this week, Grant is in line to start against a Cardinals offense that gave Beanie Wells 47 carries the last two weeks. Grant is obviously nowhere near Willis' level, but he could still pay off as a one-week spot start given that defensive coordinator Vic Fangio has shown a remarkable ability to get his defenders to play at a high level this year. Grant did a fine job himself in Willis' place last week, totaling six tackles (five solo) and a sack as the 49ers allowed just 31 yards rushing against St. Louis.
London Fletcher, LB, Redskins
McCarthy might be the IDP with the greatest shift in value lately, but Fletcher has been the hottest overall. After starting the year with just 22 tackles (10 solo) in the first four weeks, it looked like Fletcher's '11 season was going to end up a stinker. But in the eight weeks since, Fletcher has an insane total of 102 tackles (59 solo), an average of 12.75 (7.4 solo) per game, giving him a league-leading 124 tackles through 12 games. He also has one sack, one interception, five passes defensed and a forced fumble over that span.
Jabaal Sheard, DE, Browns
Sheard is primarily a deep-league and dynasty-league consideration at the moment, but the second-round pick still deserves some props for his promising rookie season. Even if the Pittsburgh product's total of 5.5 sacks in 11 games doesn't jump out, he should be on most IDP radars given his production in recent weeks. He has been red hot in his last three games, totaling 15 tackles (11 solo), three sacks and three forced fumbles. He's very quietly tied for the league lead with five forced fumbles, too.
Patrick Chung, S, Patriots
Chung (foot) could make a return from his four-game absence this week -- he has two days of limited practice heading into Friday -- but the uncertainty regarding his status makes him difficult to plan around as an owner, and the lengthiness of his absence might mean that he's not guaranteed to produce upon return.
LaMarr Woodley, LB, Steelers
After making a return to the lineup after missing three games with a hamstring injury, Woodley unfortunately aggravated the injury against the Bengals on Sunday. He missed Thursday's game against Cleveland, and even when he does get back on the field he's expected to play in a rotational role with Jason Worilds. Outside of dynasty leagues, it's difficult to argue that Woodley is worth owning in most cases.
Jamar Chaney, LB, Eagles
Chaney was having a decent season as an IDP, totaling 80 tackles (57 solo) in 12 games while adding a sack and two interceptions, but his production might drop off a bit. Chaney was relieved of his nickel-formation role in favor of Casey Matthews, which limits Chaney's snap count to obvious run situations and early downs.
Nick Fairley, DT, Lions
Fairley was doing well for himself with his expanded workload against the Saints on Sunday, finishing with three tackles and a sack, but he aggravated his highly problematic foot issue, and now no one should be surprised to see him miss more time. With an injury of such a lingering nature, it looks like Fairley might not produce in any reliable fashion until '12.
Morgan Burnett, S, Packers
Burnett's IDP value is relatively stable -- he has 77 tackles (53 solo) and three interceptions through 12 games -- but he hasn't been especially impressive on the actual field. He hasn't made much of an impact since forcing a fumble against the Rams in Week 6, totaling just 30 tackles and four pass defenses in the six games since. Getting spun in circles by Travis Beckum last week was a bit shameful, too.