A closer look at Jay Cutler's knee injury

Jay Cutler's early exit from Sunday's NFC Championship Game, which his Chicago Bears lost to the division-rival Green Bay Packers, has led to plenty of emotionally charged discussion, including criticism of the quarterback. Let's take a closer look at what we know about Cutler, specifically his knee injury.

After the game, Cutler indicated he was injured late in the first half after taking a hit to the outside of his knee. He did return after halftime for one series but subsequently departed when he could not perform effectively. On Monday, the Chicago Sun-Times reported that Cutler was undergoing an MRI to determine "the extent of a torn MCL believed to be in his left knee," citing a source close to the situation. During his Monday news conference, Bears coach Lovie Smith referred to Cutler's injury as an "MCL sprain," adding that this confirmed what the team had suspected at the time.

The somewhat vague description Smith provided of Cutler's injury does not add clarity to the situation. A sprain represents damage to a ligament, the connective tissue which, in joints such as the knee, connects one bone to another. There are varying degrees of sprains ranging from Grade I (minor, minimal structural damage) to Grade III (severe; essentially a complete ligament tear). All sprains, it could be argued, are tears since there is some form of tissue damage. It has become somewhat common, however, in the world of sports reporting to refer to a "torn" ligament only in the case of a complete tear, while the term "sprain" is generally used for lesser injuries. That said, caution is warranted when interpreting reports, as the terms are often used interchangeably. Without a specific grade of sprain, it's impossible to know just how significant Cutler's injury is.

The MCL ,or medial collateral ligament, is one of four main stabilizing ligaments of the knee, and specifically reinforces the inner aspect of the knee joint. Consequently, a blow to the outside of the knee is a common mechanism of MCL injury, and quarterbacks are particularly vulnerable because they plant on their front foot to throw the ball. New England Patriots quarterback Tom Brady was injured when a lineman rolled into his knee (on his lead leg) while his foot was planted as he stepped up to throw. Cincinnati Bengals quarterback Carson Palmer suffered a major knee injury, including an MCL tear, when he was hit while throwing. Of course, Brady and Palmer also suffered other tissue damage, including torn ACLs, which complicated their recovery. While Smith did not reference any additional injury to Cutler's knee, he did not explicitly state that there was no damage beyond the MCL.

Injury to the MCL can render the knee unstable, particularly for lateral mobility, but can also make it difficult to plant full weight through the leg. A quarterback needs to have the confidence to step up in the pocket and the strength to deliver the ball over that lead leg. He also needs to have the ability to scramble to avoid contact and protect himself. Smith addressed that issue in his news conference when he spoke of the medical decision to remove Cutler in the second half of Sunday's game. "You never want a player on the field if he can't protect himself or perform his duties," Smith said. He added that if the Bears had won Sunday, Cutler "would have been questionable" for the Super Bowl.

As to what is next for Cutler when it comes to treatment, that is also unclear. The majority of MCL injuries do not require surgery; a period of rest followed by rehabilitation to regain motion and strength is typically in order. In the case of more severe sprains, the knee might be braced for several weeks to immobilize it so the tissue can repair itself. In rare cases, such as Brady's, the ligament requires surgical reinforcement. No matter what the plan is for Cutler, he should have ample time to recover before the 2011 season.

Perhaps the moral to the story here is that it remains difficult, if not impossible, to judge the severity of an injury from a distance. Not only are all injuries unique, each athlete's response to injury is very different. Decisions regarding return to play are some of the most difficult to make for medical personnel who must balance a player's desire to return with the interest of protecting him. How a player responds under those circumstances is as variable as the personalities that make up the NFL. But as Cutler is finding out, it might be his response, more than the injury itself, which becomes the topic of conversation.