Preventing ACL Injuries


One of the most devastating athletic injuries is an anterior cruciate ligament (ACL) sprain or tear. Athletes who participate in high-impact sports like soccer, football, and basketball, are more likely to injure their ACL, but it can happen to anyone.

In the leg there are three bones that meet to form the knee. These include you femur (thigh), tibia (shinbone), and patella (kneecap). These three bones are connected in your knee by four primary ligaments. These ligaments include two collateral ligaments and two cruciate ligaments.

The medial collateral ligament (MCL) is on the inside and the lateral collateral ligament (LCL) is on the outside of the knee. These ligaments control the sideways motion of the knee and brace it against unnatural movement.

The anterior cruciate ligament (ACL) is located at the front of the knee and the posterior cruciate ligament (PCL) is located at the back. Cruciate ligaments cross in front and back of the knee forming an X and control the back and forth motion of the knee.

Sprains and Tears

Ligaments that are injured are referred to as sprains and are graded on a scale of severity.

  1. Grade 1 Sprains - Mild damage: 

    In a grade 1 the ligament has been slightly stretched but still provides the knee joint with stability. 

  2. Grade 2 Sprains - Partial tear: 

    This is where the ligament has been stretched to the point where the joint has become loose and lacking in stability. 

  3. Grade 3 Sprains - Complete tear: 

    These types of sprains are most commonly referred to as a complete tear of the ligament. The ligament has been split in to two separate pieces. This makes the knee joint completely unstable. 

These types of sprains are most commonly referred to as a complete tear of the ligament. The ligament has been split in to two separate pieces. This makes the knee joint completely unstable.

Most ACL injuries are complete or near complete tears falling in the Grades 2 or 3 category. There are many causes for these types of tears. They include: 

  • Rapid change of direction
  • Sudden stopping 
  • Slowing down while running 
  • Landing incorrectly from jumping 
  • Direct impact from a collision
Who is at Risk?

There are several factors that put people at higher risk of ACL injuries. Risk factors that can be controlled include areas like high BMI, jumping and landing mechanics, hormones, and using an appropriate playing surface.

Risk factors that are non-modifiable include areas such as genetics, age, gender, and anatomy of the knee. Those with a previous ACL tear are 15% more likely to reinjure the previously repaired ACL.

One of the most notable differences that put an athlete at risk is gender. Females are four to six times more likely than males to sustain an ACL injury. In fact, females who play soccer or basketball year round have an ACL tear rate of approximately 1 in every 20 athletes. Many factors contribute to women being at higher risk for ACL injuries. These include strength, genetics, performance patterns, and anatomy.

Things you can do to prevent injury:

Many things can be done at home to help prevent ACL injuries.

Stretching: It is important to be flexible enough to move freely and be able to maintain ideal form. Focus on stretches for your thighs, calves, and hips. Pay attention to your body and areas that are particularly tight.

Strength Training: Having adequate strength in your hips, thighs, and core is key to providing support to the knee and preventing ACL injuries. Activities such as squats, single leg squats, lunges, lunges with a twist, walking lunges and single leg deadlifts are good places to start.      

Core Strength: Improving muscle strength around your back, chest, and abdomen can improve overall form and decrease unnatural movement to the knee. For core strength use exercises such as side planks, hip bridges, chops and lifts, and multi-directional shuffle steps.

Balance Exercises: Many injuries occur when an athlete is off balance. Gains in this area come from repetition and will greatly decrease your risk for injury. Balance exercises include a ball juggling, a single leg ball pass, and other single leg activities.        

Agility Training: Get comfortable with agility and change of direction. Do cone drills with a strong focus on form. Move in patterns that take you from front to back, side to side and diagonally. Start slowly to focus on good form. From their increase your pace while maintaining good form. Always remember to keep you kips over your knees and your knees over your ankles.          

Practicing Good Form: Practice good jumping technique. Jump straight up several times. Jump and land with your knees and feet point straight ahead. Do not allow for your knees and feet to bow or turn. Let your knees bend softly each time you land. Ask someone to watch your form and provide feedback. Remember to keep your chest high and have good alignment. Incorporate catching a ball to this while maintaining good form. Progress to jumping laterally while focusing on knees and feet straight. Increase speed but maintain form. In all of these exercises it is always important to keep proper form. Quality is always valued over quantity.

Finally and equally important is to allow your body to rest. Don’t allow your busy schedules to allow fatigue to impact your technique. Rest is essential for gains to occur. Make time for sleep, rest days, and alternate with lighter workouts.

Hear Jada's story about her experience with an ACL tear and her road to recovery.