Week 16 injuries: Adrian Peterson facing lengthy rehab

Adrian Peterson's 2012 status is now up in the air thanks to a torn ACL suffered in a meaningless Week 16 game. (AP) It's bad enough to see a player suffer an

Adrian Peterson's 2012 status is now up in the air thanks to a torn ACL suffered in a meaningless Week 16 game. (AP)

It's bad enough to see a player suffer an injury while his team's in the thick of the playoff race. In a lot of ways, though, it's even more heartbreaking when someone hits the turf in a meaningless, late-season game.

But that's exactly what happened to Adrian Peterson Saturday in Washington, in a game that could not have gone much worse for the Vikings -- in addition to Peterson's knee injury, rookie QB Christian Ponder suffered a concussion, and Minnesota won to eliminate itself from the No. 1 pick race.

SI.com injury expert Will Carroll once again hops on board to help us break down Peterson's prognosis, as well as the outlooks for some other players injured in Week 16:

• Adrian Peterson, RB, Vikings (knee): Minnesota's superstar running back suffered a gruesome injury when he took a helmet on his left knee, which caused his leg to bent awkwardly. Peterson tore both the ACL and MCL in his knee.

Carroll: There's going to be a lot of ink and pixels burned on this, perhaps the biggest injury of the season. Yes, bigger than Peyton Manning. Peterson, in theory, is in the prime of his career, just as important to his team's future, and also signed long term. Players come back from ACL surgery all the  time -- Wes Welker, Carson Palmer, and Edgerrin James are good comps here. Welker came back in eight months and without issue from a similar injury; Palmer also had a severe traumatic O'Donoghue's Triad (which is the combo of ACL, MCL, and meniscus damage) and came back; James is a positional and physical comp, and while he didn't come back to the theoretical 100 percent, he did come back and play well for a number of years at a high level.

It's hard to separate age and wear from the effects of the surgery, which is to say, ignore the surgery. Ignore the ligaments. The key is the amount of cartilage damage Peterson suffered. He should be on the normal 8-to-12 month rehab scheduler, which would have him back anywhere from training camp to mid-season 2012.

Who takes Peterson’s spot?: For the Vikings' final game of the season, it'll be Toby Gerhart. How Minnesota proceeds into 2012 depends on Peterson's rehab timetable.

•Tony Romo, QB, Cowboys (hand): Romo whacked his hand on the helmet of an Eagles' pass rusher early Saturday and did not return.

Carroll: Sometimes people punch walls. That's essentially what Tony Romo did, except the wall was a lineman coming at him and the helmet didn't give. Romo's hand was bruised, not broken, and swelled up visibly. It hurts and will affect his grip, but shouldn't be a long-term injury. Once the swelling comes down and his grip is back, he should be fine. This is why boxers wear gloves.

Who takes Romo’s spot?: With Jon Kitna on injured reserve, the Cowboys had no choice but to turn to Stephen McGee. Romo should play in Week 17 against the Giants, but McGee will again be Plan B.

•LeSean McCoy, RB, Eagles (ankle): McCoy limped off Saturday and was sent to the locker room for X-rays. He returned for a brief time, but spent the majority of the late stages on the bench.

Carroll: A simple ankle sprain can be darned painful. LeSean McCoy didn't do any long-term damage when he rolled his ankle Saturday, but well behind Maurice Jones-Drew for the rushing title and eliminated from the playoffs, McCoy doesn't have anything to play for either. The Eagles should and probably will be conservative with him.

Who takes McCoy’s spot?: Philadelphia's playoff hopes are over, so the Eagles may opt to rest McCoy in favor of Ronnie Brown for much of Week 17.

•Reggie Bush, RB, Dolphins (leg): Bush sat out Miami's last couple of drives Saturday after injuring his right leg. He said later he did not think it was serious.

Carroll: Reggie Bush was finally durable enough to put up solid numbers for a full season. His leg injuries stayed away (apparently handed down to Daniel Thomas, who left Saturday's game with a knee injury.) Bush had a mild hamstring strain in the game, a reminder for anyone who believes in him that signing him based on his one good year ignores the five previous injury prone ones.

Who takes Bush’s spot?: Thomas' injury could leave the Dolphins scrambling in Week 17 if Bush cannot go. Lex Hilliard might be the next in line for carries.

• Matt Light/Logan Mankins, OL, Patriots (leg/knee): Light was a surprise scratch late Saturday after tweaking his ankle in warmups. Mankins then fell during the Patriots' win, when Jared Odrick landed on his leg, leaving New England very thin up front.

Carroll: Once the Pats adjusted to their line being shorthanded, they played like we're used to seeing from Tom Brady and crew. Mankins' injury is the more worrisome of the two. He'll have further tests early this week, but any damage could affect his playoff status. Light will rest a few more weeks and hope he can hold up in the playoffs.

Who takes Light and Mankins' spots?: Rookie Nate Solder had to step in at left tackle, with Donald Thomas jumping into Mankins' spot at left guard. That would be the look in Week 17 if neither Light nor Mankins returns.

• Brian Dawkins, S, Broncos (neck): Dawkins suffered his third neck injury of the season Saturday, less than a week after sitting out vs. the Patriots because of an issue in the same area.

Carroll: Tingling in the arm. Weakness. Reduced range of motion. This describes why Peyton Manning needed neck surgery and also describes what Brian Dawkins is dealing with. There's likely a herniated disc in there, the result of one hit or an accumulation of hits. Did you know that defensive players have a tendency to lose height during their NFL careers due to the sheer force and compression put on their spine by repeated hits? It's the second scariest thing I've ever heard about the NFL.

Who takes Dawkins’ spot?: David Bruton jumped back into the lineup at safety for Dawkins, and if the situation with Dawkins is as serious as it sounds, he might be in line for a lot of playing time going forward.

•Delanie Walker, TE, 49ers (head): Walker was carted off after taking a knee to the head from Seattle linebacker LeRoy Hill. Initial reports indicated that he suffered a concussion, as well as a possible broken jaw.

Carroll: Walker's head was hit by a knee, causing his helmet (unsnapped, mind you) to fly off. He then hit the back of his head on the turf. One hit is bad, two is worse. At some point, the NFL's just going to have to say that players have to snap their helmets. There's no need to unsnap them every play, but there is a need to have properly fitted and properly worn protective gear.

Who takes Walker’s spot?: Vernon Davis remains San Francisco's top option at tight end, but Justin Peelle might be forced into action in Week 17 and the playoffs.

•Patrick Peterson, CB, Cardinals (Achilles): Peterson had to leave Saturday's game early with what was deemed a strain to his left Achilles.

Carroll: Patrick Peterson might be the next Darrelle Revis, the next Devin Hester or a combination of both. Right now, he's the next Troy Polamalu. Last year, Polamalu was slowed at the end of the season by an Achilles strain. Peterson's is very similar -- a mid-grade strain near the origin of the tendon. It will heal without surgery, but further strain in this weakened state could cause a full rupture. (By the way, any sprain or strain is a tearing of the fibers. Where most say "tear", they mean "rupture", which is a complete tearing. This knowledge comes in handy and will keep you from tweeting things like "Whew, it's just a sprain. I thought it was torn.")

Who takes Peterson’s spot?

Andre Roberts