How to Avoid the Ominous ‘Pop’ That Signals a Knee Injury

Proper form is important when pivoting, turning and landing

How to Avoid the Ominous 'Pop' That Signals a Knee Injury

Contributor: Lutul Farrow, MD

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Athletes know the unmistakable “pop” when they’ve torn their anterior cruciate ligament (ACL). The injury can put a quick end to the season and sometimes requires surgery and extensive rehabilitation.

Proper form can help athletes avoid this serious injury.

If you play soccer, basketball, tennis or volleyball, you should be especially mindful of two things:

  • How you “cut” – taking hard, quick steps to accelerate in another direction
  • How you “plant” – landing on your feet from a jump or a step

These cutting and planting maneuvers cause about 70 percent of all ACL injuries. The jumping, landing and pivoting involved in these sports all stress the knee’s ACL — particularly in female athletes.

Initiating a cut or landing after a jump can compromise the ACL’s ability to resist rotational forces. Planting incorrectly can overwhelm the ACL’s ability to move the knee the way it is designed to do.

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How the ACL works

The knee’s four main ligaments tether your shin bone (tibia) to the thigh bone (femur) where they meet at the knee.

The ACL plays a vital stabilizing role. It keeps the tibia from sliding up under the femur. It also limits over-rotation of the knee joint.

Female athletes at higher risk

Men and women athletes maneuver differently in a jump or cut, which puts women at higher risk for injury.

Women tend to activate their quadriceps first, while men tend to activate their hamstrings first. This difference in activation may alter the amount of strain applied to the ACL and other knee ligaments.

In addition, after a jump, women tend to land with their knees closer together than men. Athletes who land with their knees farther apart seem to have less risk of ACL injury.

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Fatigue: a problem for both sexes

Fatigue is a hazard for male and female athletes. Tired athletes are more likely to use poor mechanics.

For example, they may land with their knees closer together. This is especially true when a fatigued athlete makes a split-second decision to execute an unexpected move.

Supervised training reduces risks

Studies show that training programs supervised by sports health professionals improve athletes’ leg strength and jump-landing techniques.

Proper training decreases ACL injury rates in basketball, volleyball and soccer. The techniques that improve ACL safety can also enhance performance, and increase vertical jump height, acceleration and the ability to change direction.

Nothing can prevent ACL injuries altogether. But knowing the potential causes and maximizing your prevention strategies can stop the “pop” and its frustrating consequences.

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