By: Sydonya Barker for Knee1Of the more than 300 injuries reported in the NFL since football season began in September, thirty-five percent are knee-related – making knees the body part most susceptible to injury in the sport.
The soft tissue components of the knee make it vulnerable to injuries, especially for athletes. “Knee injuries are very common… Just living life puts you at risk,” says Dr. Rick Wright, a sports medicine specialist at Washington University in St. Louis, MO.
As the largest joint in the body, the knee is supported by four ligaments that hold the bones together.
The collateral ligaments on both sides of the knee provide side-to-side stability. The lateral collateral ligament (LCL) is located on the outside of the knee. The medial collateral ligament (MCL), located on the inside of the knee, is usually injured when an athlete’s firmly planted foot receives a blow to the outside of the knee, causing the knee to bend inward. Pain is the most common symptom of an MCL injury. Still, athletes can usually return to competition right away. Swelling and bruising generally occur one to two days later.
The two other ligaments, essential for proper alignment, are the posterior cruciate ligament (PCL) and the anterior cruciate ligament (ACL). Both the PCL and ACL are inside the knee and cross each other as they stretch diagonally from the bottom of the thighbone to the top of the shinbone. They provide front-to-back stability for the knee joint.
“Of the four major ligaments of the knee, injury to the ACL is most common,” says Dr. John Pinkowski, General Orthopedic Surgeon at Akron General Medical Center in Ohio. Each year, 95,000 to 250,000 people in the United States sustain injuries to their ACLs.
The ACL controls movement of the lower leg by preventing the shinbone from moving too far forward away from the knee. ACL injuries occur most frequently when athletes pivot with their feet firmly planted on the ground. These sudden rotations cause the knee to overextend. As such, ACL injuries do not usually result from contact with other players.
In recounting his experience with an ACL injury, high school quarterback Jeremy Belanger said, “My knee popped…I knew it was torn.”
Like Belanger, many athletes report feeling or hearing a “pop” in their knees after an ACL tear. The immediate swelling that follows is the result of small blood vessels bleeding into the joint empty space.
Other important features of the knee’s anatomy are the menisci—the two cartilage disks resting between the thighbone and the shinbone.
As the shock-absorbing cushions of the knee joint, menisci distribute bodyweight between the thighbone and the shinbone.
Degenerative injury occurs in the menisci over time; the older one gets, the softer the menisci become. With most athletes, however, traumatic injury results when they are hit in the knee from the side. Similar to an ACL injury, a torn meniscus causes sharp pain, swelling, and very often, athletes hear a “pop.” If the tear is large, the knee can feel locked because the torn cartilage can obstruct the joint’s mechanics. The knee must then be “wiggled” into place.
When football players are hit on the outsides of their knees, the ACL, MCL, and the menisci can tear simultaneously resulting in the “unhappy triad.” Although originating from the same place, treatment options for each injury are different.
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Some Knee Injuries in the NFL
1. Ray Lewis - Ravens
2. Mike Alstott - Buccaneers
3. Deion Branch - Patriots
4. Troy Vincent - Bills
5. LaVar Arrington - Redskins
5. Duce Staley - Steelers
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An athlete can usually treat an MCL or LCL injury by wearing a knee brace because these injuries often heal on their own.
A torn meniscus, however, threatens the shock-absorbing quality of the knee and increases the risk of developing arthritis in the joint. However, many people live normal lives despite tearing their menisci.
ACLs require the most serious treatment because this ligament does not heal when injured. Not everyone requires surgery, however. Usually, one-third of patients do well with rehabilitation alone; another third may avoid surgery by lowering their activity level; and the final third of patients require surgical intervention.
Although knee injuries are not entirely preventable, proper warm-up routines can increase flexibility in the knee joint thereby reducing risk and injury.
