The term ACL is something that we are all familiar with. More often than not, when someone thinks or talks about the ACL, it is connected to an injury. Whether you have had an ACL injury or not, it is extremely likely that you know someone that has. ACL injuries are common, especially when it comes to athletes and even more so when it comes to female athletes.

Dr. Michael Parman and Dr. Ryan Ziegler’s discussion on ACL Injuries in Youth Female Athletes provides an in-depth explanation to what the ACL is, how ACL injuries occur and how they are treated, along with why these injuries occur more often in female athletes and how they can be prevented.

What is the ACL?

The ACL, or Anterior Cruciate Ligament, is one of four main ligaments in the knee and is located within the intercondylar notch. Ligaments are soft tissue structures that connect one bone to another bone and provide stability for a joint. The ACL is the ligament that connects the femur (thigh bone) to the tibia (shin bone) and prevents excessive translation, or shifting, as well as rotation of the tibia in relation to the femur.

How Common are ACL Injuries?

ACL injuries account for a large proportion of knee injuries sustained while playing sports, and most resulting in surgery. In the U.S. alone, there are approximately 400,000 ACL reconstruction surgeries each year (Murray, 2021).

When comparing ACL injuries to males and females, women are more prone to an ACL injury than men at a 3-6:1 ratio (Parsons et al, 2021). This means that female athletes are, on average, five times more likely to sustain an ACL injury than their male counterpart. Additionally, females tend to sustain ACL injuries at a younger age compared to males.

How do ACL Injuries Occur in Athletes?

There are two common ways or mechanisms that an ACL Injury can occur in athletes. The first way an ACL injury can occur is from direct physical contact to the outside of the knee. This typically occurs in contact sports, like football. Injuries that occur this way are more difficult to prevent and typically result in significant trauma to the knee with multiple structures, including the ACL injured.

The second way the ACL can fail, and the most common way, is through a non-contact, pivoting injury. This is when the athlete’s foot is planted and the bones of the leg twist in opposite directions under full body weight. For example, the femur internally rotates while the tibia externally rotates. While the ACL is responsible for preventing too much tibial rotation, it will ultimately fail, and rupture, if too much force is applied. This injury typically occurs in sports that require sudden, quick changes in direction such as soccer, basketball, and football.

The risk of sustaining an ACL Injury caused by a non-contact, pivotal rotation can potentially be reduced by certain rehab and strengthening exercises prior to competition.

Treatments for an ACL Injury

A combination of history, how the injury happened, physical examination, and imaging are crucial when determining whether an athlete has a torn ACL. Typically, after an initial exam of the knee, the physician will order an MRI to evaluate the ACL along with other ligaments within the knee as well as the cartilage and meniscus. Once the doctor determines that the ACL is torn, they will then decide on the best treatment plan for the patient.

When it comes to ACL injuries in athletes, the current recommendation is surgical reconstruction of the torn ligament. This is done to re-create the stability that the original ACL provided to the knee joint, allowing athletes to return to sport as well as protect against future cartilage, meniscus, and joint degradation.

Why are Female Athletes more Prone to ACL Injuries?

So why do female athletes tear their ACL at a higher rate than their male counterparts? The answer is that there are multiple factors that can play a role in this. Some of these risk factors are non-modifiable and are simply due to the differences in anatomy between males and females. For example, women tend to have a smaller diameter ACL, along with a smaller intercondylar notch which can impinge on the ACL during tibial rotation. Additionally, females have a higher tendency of hypermobility/joint laxity or being loose jointed, putting the ACL at higher risk of becoming injured.

Modifiable risk factors include poor landing mechanics, lower hamstring to quadriceps ratio (quad dominance) and core stability. Females have a tendency to land or plant their feet with increased knee valgus and extension. This biomechanical risk factor puts the knee in a vulnerable position, especially when associated with a sudden change in direction.

Fortunately, an athlete’s landing mechanics can be improved by strengthening these neuromuscular risk factors, hip abductors and core muscles, along with learning proper landing techniques. By working on these improvements, the athlete can, in theory, limit the number of times they are putting their knees at risk of an injury.

Local Strength Training Programs:

Appleton – Blaze Sports & Fitness

• Speed & Strength Youth Program – The Speed & Strength Youth Programs at Blaze feature six key components: Dynamic Warm-up, Balance, Power, Agility, Speed, and Strength Training.

• Sports Performance – Blaze Sports and Fitness offers Sports Performance Training with their professional coaches who have collegiate to professional coaching, and training experiences. They provide sport-specific experience from coaches at all levels, so you can learn from people who know what it takes to perform at a high level in the high school, college, and professional arenas.

Green Bay: Synergy Sports Performance

• Athlete Performance Class – Synergy’s speed class will help athletes develop skills that boost performance in every sport. We will learn running technique and form, stabilization and strength, linear and lateral quickness. Our athletes don’t just work to be fast. They’re strong, agile, powerful and determined to succeed at whatever they take on!

Prevention Programs:

• NMT Pre-Season Programs
  • Sportsmetrics
    • 6-week program3 days/week90-minute sessionsFocuses on “dynamic warmups, plyometrics, jump and strength training”.Essential Components included neuromuscular and muscle strength.
  • Prevent Injury and Enhance Performance (PEP) Program
• NMT Warm-up In Season Programs
  • FIFA 11+
    • 20-minute program
      • Focuses on “cardiovascular and preventive exercises in a three-level progression difficulty.
    • Replaces customary warm-ups.
    • 15 exercises
  • WIPP (Sportsmetrics), NCAA, Olympic, etc.

Preventing an ACL injury takes effort, but it is important to note that the hard work will pay off. Data shows that injury prevention programs work. One study showed that Plyometric Training decreased peak landing forces by 22%, decreased knee adduction and abduction moments by 50%, increased ham-quad muscle peak torque ratio by 26%, and increased hamstring muscle power by 44% (Hewett et al, 1996). Overall, there was an 88% risk reduction of all lower extremity injuries, not just ACL injuries (Noyes &Westin, 2014). Furthermore, another study shows that after performing the FIFA 11+ prevention program, there was a “significant reduction in overall leg injuries, overuse injuries, and severe injuries” (Soligard, 2008).

If you or someone that you know is suffering from an ACL Injury, Schedule an Appointment with Dr. Parman, Dr. Ziegler, or another OSMS physician.

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ACL Injuries in the Female Athlete
Author: Frank Noyes
Textbook

FIFA 11+ ~ A Warm Up Proven To Reduce Injuries – Jubilee Sports Physiotherapy