Kneed Some Rehab

NFC Championship game shines light on knee injuries

/ Author:  / Reviewed by: Joseph V. Madia, MD

In the aftermath of the Chicago Bears' 21-14 loss to the Green Bay Packers in the NFC Championship game, it seemed like the blame was placed squarely on the shoulders of Bears quarterback Jay Cutler.

Cutler wasn't blamed so much for his sub-par performance as he was for not playing and leaving the game with what was later diagnosed as a sprain of the medial collateral ligament (MCL) in his left knee.

The immediate response from former and current NFL players on Twitter was quite negative, with many questioning his toughness and saying that they would have played through the injury, which begs the question: Can someone really play football with an MCL sprain? Let's take this opportunity to look at the parts of the knee that are commonly injured in athletics, and what athletes can do to overcome them.

Medial Collateral Ligament (MCL)
The MCL runs down the inside part of the leg and connects from the femur (thigh bone) to the tibia (the shin bone that runs down the front of the leg). Providing structural support to prevent the knee from bending inwards, in a movement called valgus stress is one of the main purposes of the MCL. It is no wonder that the MCL is commonly injured in skiing (landing hard) and in football when a force strikes the outside (lateral) part of the leg, causing the MCL to be stretched too far and causing a sprain.

Any level of MCL tear is referred to as a sprain regardless of how badly the fibers are torn, and are graded from first-degree, meaning only a few fibers are torn, through a third-degree sprain, meaning the entire ligament has been torn in half. The MCL has a counterpart on the outside of the knee, the Lateral collateral ligament (LCL), but because of its flexibility, the LCL is rarely injured as often as the MCL.

Treatment for an MCL tear consists of the “RICE” method – rest, ice, compression, and elevation – with the severity of the sprain determining the length of treatment. Grade I sprains may take 1-2 weeks for the person to get back to normal, grade II, 3-4 weeks, and grade III sprains up to 3-4 months for complete rehabilitation, often with some time spent on crutches and in a brace. Surgery to repair the MCL is not common unless a patient has multiple ligaments in the knee that are injured and also need repair.

Anterior Cruciate Ligament (ACL)
Most sports fans or athletes will have heard of the ACL, as it is the most commonly injured ligament in the knee. In layperson's terms, the ACL runs from the femur to the tibia in a direction that could best be described as from the back of the femur to the front of the tibia. This connection prevents the tibia from moving forward from underneath the femur (imagine a dog on a leash jumping forward, the dog being the tibia, the dog walker being the femur, and the ACL as the holds the tibia back). Eighty percent of ACL injuries are 'non-contact' injuries, meaning that the knee does not sustain a blow when the ACL is ruptured, but the injury instead comes from a sudden change in rotational force, like a quick pivot or change in direction that's too forceful for the ligament to sustain (there's also a characteristic loud “pop” that occurs when it tears, usually to the horror of the victim and those around within earshot).

Treatment for an ACL tear is rehabilitation, corrective surgery, or both, but not everyone who suffers an ACL tear will need surgery. Usually young people or athletes who want to return to their previous level of activity will need surgery, since the instability caused by the tear often affects performance. Older people or sedentary individuals who don't expect to participate in a triathlon or climb Mt. Kilimanjaro, may benefit from simple rehabilitation.

Posterior Cruciate Ligament (PCL)
The PCL, located inside the knee joint, is the counterpart to the ACL. Like the ACL, the PCL provides stability and prevents movement of the tibia away from the femur, but in the opposite direction that the ACL does. The PCL connects from the anterior part of the femur in a downwards and backwards direction, preventing the tibia from sliding out in a backwards direction from under the femur.

Contrary to ACL injuries, the PCL is often injured from a direct blow causing a hyperextension of the knee (when the knee bends too far forward). An example would be if a ball carrier in football was tackled by being hit from the front, directly in the knees, causing him to fall forwards while his foot was still planted in the turf.

In non-athletes, a PCL injury is common in people who are in car wrecks and have their bent knees strike the dashboard of the car, causing the shins to be forcefully pushed back. In addition, the movment and impact that result in PCL tears also tend to tear the MCL as well, causing a condition called multidirectional instability.

Like MCL injuries, PCL tears are graded I through III. Grade I and II injuries are treated through rehabilitation and strength training of the quadriceps (front thigh) muscle, while only grade III tears are candidates for surgery. Because of the difficulty of the surgery, PCL repair is controversial and its value debated among orthopedic surgeons. Only candidates who have severe instability or negative impact in their quality of life usually end up getting surgery.

Can You Play?
The level of activity that an athlete can or can't sustain with one of these injuries is very individual. In the case of Jay Cutler, it was reported that his injury happened late in the second quarter of the game, and he was eventually pulled early in the third quarter because the instability caused by his injury was making it difficult for him to throw the football accurately, and the sudden lack of mobility was making him a liability on the offense.

Unfortunately for him and for Bears fans across the country, he'll have the entire offseason to rehabilitate it, as well as watching the Super Bowl on television with the rest of us.

Review Date: 
February 1, 2011