People often ask me why I don't use the normal designators -- out, probable, questionable, and doubtful -- when referring to injuries. The fact is that the Official Injury Report uses very clear definitions for those terms while I have a bit more gray area in mine. I'm more concerned with the effects of the injury rather than whether or not someone will merely play and I continue to think that it's more valuable as well. The OIR has its uses and it works; studies of the use of the designations shows that teams are not gaming the system and that players in aggregate come very close to the defined percentages. I don't deal in averages; I deal in specifics, trying to dig into the injuries through information and sourcing. Heck, I'd rather invent my own terms anyway. Let's get to it:

The Steelers are keeping things very close to the vest on Parker. So far, they've only said that he has a sprained knee, leaving us to guess on the severity and his timeline. At this stage, all we know is that he's out this week, but going forward there are a lot of things that come into play. It's safe to say that the injury isn't sending him to surgery, or he would have been in by now. There's a precedent for teams being able to keep a surgery secret, as was done last year with Philip Rivers during the playoffs, but that's pretty tough to pull off. The most likely scenario is an MCL sprain, something he'd need a couple weeks of rest at least and then return with a brace. Depending on the severity, the secondary support structures, and his leg's strength, Parker could return from that at level, more or less. It's all speculation, and just as important is how the team plays with Rashard Mendenhall taking the feature role. If Mendenhall performs as well as the rest of this class of rookie RBs, the Steelers will get some extra time to get Parker back closer to perfect.

"Strain: a tearing of muscle or tendon." It's the simplest definition, but key in understanding what's happening with Westbrook. It could have been much worse, such as another Lisfranc or other foot injury. It might have been a severe sprain or high ankle sprain. With a strain, the most likely area is the Achilles tendon, which is the strongest tendon in the body, but something of an all or nothing area. When it snaps, it's fixable, but a player is done for the season. Westbrook suggested in a radio appearance that the damage was to "ligaments and tendons," so there might be more going on here that just a strain, but Andy Reid specifically said there was no ligament damage in his press conference. At this stage, there's just not enough information to know exactly what's going on, making analysis something of a wait-and-see proposition. Westbrook's practice this week (or lack thereof) might not be indicative either, as the Eagles have shown a tendency to let him rest during the week when it was his chronic knee issues slowing him. As for Donovan McNabb, he has a bruised sternum. It's a painful injury, but should heal up normally and quickly. He shouldn't have any deficits heading into Sunday.

Favre just plays. Let's face it, love him or hate him, he's always going to show up at kickoff. We know he loves a challenge, that he wants the things that he doesn't think will just be given to him, and that he still feels that near-insane persistence that keeps him chasing things he may never get. The Jets aren't a great team, and even with Favre in place of Chad Pennington, the Iron Chef Excels over at Football Outsiders think it's about a one-win improvement. Favre's sprained ankle will likely keep him out of practice and limit his movement on Sunday, but as with many QB injuries, we have to look at his style of play. He's more mobile than most realize, not necessarily in a tuck and run way, but he does move out of the pocket to buy time. Being slowed a bit is going to force his line to keep him protected more, which could shift some focus to the running game early. Word is that Kellen Clemens will be ready, just in case Favre has to be pulled for his own protection.

Fantasy players seem happy about the points Tomlinson put up on Monday night. He managed to score a couple times, catch a couple passes, make some yardage and didn't do the same thing to his owners he had done in Week 2. Still, it's the low average and lack of burst that have fantasy owners worried. Without some magical cure, Tomlinson's toe isn't going to heal in a snap; it's going to take time and rest, two things you just don't get between games, especially in a short week. Tomlinson ran behind his line and took the "easy" yards rather than looking for the big break, which just never came. It's smart in ways, since he's unlikely to be able to take advantage of those holes and he has to be more concerned with making the positive yardage he can than getting caught improvising. With the bye week a ways off, Tomlinson isn't so much a risky play as he is one that's unlikely to get you the value you expected when you drafted him No. 1.

McFadden played through turf toe last week and was productive, if not explosive. One detail that's been offered in some stories actually tells us a lot more than anything else: McFadden went through three pairs of cleats, seeking a comfortable level of traction due to his inability to "dig in" the front and get acceleration. With the steel plate and a numb toe, McFadden had no way to do something that comes naturally to him, and because of that, couldn't use the burst he possesses. While Lane Kiffin thinks the toe will magically clear up, he should check the college scouting on his young RB. McFadden had a very similar injury -- a dislocated toe, injured in a bar fight -- back in his college days and it took him about six weeks to come back, and even then was slowed. Turf toe doesn't heal overnight, so I'd expect McFadden to be very similarly limited this week -- he didn't practice on Wednesday -- then to use the bye week to clear things up.

At 3-0, you'd think that the Titans were having no issues at all, but that's certainly not the case. They're using a backup QB, a timeshare at RB, and are missing their WR1. Gage missed last week with a strained groin and things are looking rough for Week 4. However, it was Gage, not Justin McCareins, who was on the field Wednesday. Don't read too much into this since, as one observer told me, "Gage wasn't banged up from the game." It's an interesting point, but Gage's groin is still slowing him, especially on deceleration, forcing Gage to jog to slow rather than simply stopping. We'll have to watch the practice reports, but I have a feeling Gage may well be a "check with me" come Sunday.

The Vikings need all the help they can get, and Rice looks to be helpful this week. Coming back from a PCL sprain in just two weeks is nice healing, but this season is showing us that we have to once again re-set the rehab clocks for players coming back from knee injuries of all sorts. Whether it's Philip Rivers or Jeff Saturday, knees are becoming nearly routine recoveries when just a few years back they'd have been season, and even career, enders. Rice will be playing braced, so he may have some trouble with acceleration and separation, but the offense can adjust to those limitations through smart routes. One thing to keep in mind is that even with Bernard Berrian slowed, Aundrae Allison has been a solid option, meaning Rice is likely to function as WR3.

Harris wins the Ronnie Lott Award this year, or would if that was real. Harris apparently asked to have his spleen removed post haste after his injury on Sunday. Why? He apparently thought the quicker he had the splenectomy, the faster he could come back. He even suggested he might not miss a game. Look, I can admire courage and grit, but I can't admire ignorance. Harris is out for this week because the doctors treating him have better sense than he does. Harris' attitude really isn't that odd in the NFL and is one of the reasons players need good, independent care, if only to protect them from themselves when they go for the Lott nomination.

I like Green. He's a great story and a smart guy. I worried when he went to Miami last year, knowing that he was one big hit away from losing those smarts and so much more. He doesn't need the money, but as Brett Favre showed us, sometimes it's really not about the money for these guys. Green's severe concussion in 2006 remains a danger, and one more bad hit could lead to more permanent damage. Green was lucky to come back as well as he did from a hit with the force that one head injury expert felt might have decapitated some people. I can only hope he has some of that luck left and that it rubs off on the Rams offensive line.

Adrian Peterson will play this week and should get a similar workload to last week, around 20 touches, plus some receptions. Watch Chester Taylor however. He was limited and could shift some of those touches back to Peterson ... Steven Jackson missed practice Wednesday with a sore groin. Remember what limited him last season? ... Roscoe Parrish will miss a month after thumb surgery. It's almost the same injury that put Marques Colston on the shelf ... Vince Young is back at practice, but he's a few weeks away from even being considered for playing time ... Everyone describes the Lions as "hapless." What the heck is "hap"? ... Doesn't look like Joey Galloway will be ready to go this week, though his foot is "improving" ... Donte Stallworth looks like he'll be available this week, but Braylon Edwards is still limited by his shoulder ... Devin Hester was held out of practice Wednesday and looks unlikely for Sunday ... A Week 5 return for Kevin Curtis is possible, though the emergence of DeSean Jackson makes it less of a rush ... Can defenses be an injury predictor? Playing against Tennessee and Philly sure seems to be. Longtime friend Rick Averyt says that the Philly defense "molested" the Steelers last week, but physical play and a couple big hitters can rack up injury numbers and slow offenses the following week.

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