Knee injuries... an ounce of prevention will help you long term

Every youth athlete will have an injury to deal with at some point during their time participating in a youth sports league or ona high school sports team. One of the most devastating injuries is an ACL injury.  This is one of the most prevalent injuries at every level of sports. According to a study conducted by the American Academy of Pediatrics (AAP) presented on October 24, 2015 at the National Conference, ‘The incidence of Anterior Cruciate Ligament (ACL) tears has increased over the last two decades, with overall incidence increasing 2.3% percent, where the incidence was higher in females than males’. There was as annual 3% increase in the proportion of Anterior Cruciate Ligament (ACL) tears treated surgically during the study period; from 55% in 1994 to 75% in 2013.  Also, adolescents have a number of unique risk factors that differently affect their injury risk profile, including player variation in size and skill, and potentially underdeveloped sensory and neuromuscular control, as explained by Alex Gornitzky.  According to the Centers for Diseases Control (CDC), “the anterior cruciate ligament Anterior Cruciate Ligament (ACL) injury affects as many as 250,000 individuals in the United States annually. Resulting in an annual health care cost exceeding $2 billion, this injury typically occurs in the physically active population, and while the incidence of ACL injury is greater in males due to greater exposure to physical activity, the relative risk of injury per exposure is 2 to 8 times greater in females.” (

It has been found in numerous studies that one of the key factors that contribute to an increased chance of an Anterior Cruciate Ligament (ACL) injury is instability of the knee joint due to inactivity and or muscular stiffness in the hamstring. A strong flexible hamstring is a key factor in limiting the load placed on the ACL during physical activity reducing the risk of injury.  There are also several other key factors that are speculated to increase risk of injuring Anterior Cruciate Ligament (ACL) in female athletes including but not limited to:

·        Lower extremity alignment (wider pelvis, knee valgus, foot pronation)- “knocked kneed” “flat feet”

·        Joint laxity

·        Hamstring flexibility

·        Muscle development-  strength imbalances 

·        Hormonal differences  

·        and ACL size 

I have personally seen dozens of ACL injuries over my collegiate and professional career, and as a parent of athlete. One of the worst ACL injuries is the non-contact Anterior Cruciate Ligament (ACL) injuries that are common in most sports, like soccer, lacrosse, basketball, and volleyball, and football. All of the above mentioned factors are interconnected and can be address with the help of a comprehensive training program that is designed to improve any strength imbalances, bio-mechanical issues, and mobility issues.  There are training methods that can be implemented into a training regimen that can help reduce the risk of sustaining a Anterior Cruciate Ligament (ACL) injury, and should be added to the training program for athletes at all levels specifically designed by a professional trainer.



One of the key factors that can increase the risk of an Anterior Cruciate Ligament (ACL) injury, are significant strength imbalances in the lower extremities. 

Specifically, the hamstring muscles are comprised of three muscles, the semitendinosus, semimembranosus and the biceps femoris.                                                                                   


The quadriceps Femoris muscles (“Quads”) has four parts: rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius.


And the three main muscles that comprise the  Glutial complex or “ butt”: gluteus maximus, gluteus medius, gluteus minimus.


Improving the strength imbalances in these three areas of the lower extremities can reduce the risk of a Anterior Cruciate Ligament (ACL) injury.

There are possible ways to reduce the risk of an Anterior Cruciate Ligament (ACL) injury, which consist of  addressing specific movement patterns through corrective exercise such as proper ankle, knee and hip alignment and improving ankle. This is often refered to as an individual being “Knock Kneed” or the technical term Valugus where the knees internally rotate and collapse inward, as shown below:

Foot, ankle and hip mobility are another risk factor.  When these  multi-directional joints and limbs  have a limited range of fundamental motion, the joint in the middle will be subject to movement patterns that increase the risk of injury, especially to the Anterior Cruciate Ligament (ACL).

According to Recent studies conducted by Barber-Westin SD, Noyes FR, Galloway M*,  revealed that young female athletes are four to six times more likely than boys to suffer a serious non-contact ACL injury.  This discrepancy between male and female athletes and the increased risk to sustain non-contact a Anterior Cruciate Ligament (ACL) injury  is due to several factors:

1.       Structural differences such as degree of knee laxcity, Q angle (referring to the width of the hips in comparison to the knee joint) which may cause undue stress on the knee which may lead to a vulgus knee (refered to as being “knock kneed”)

2.      *Females have a higher tendency to have risky landing patterns that are associated with ACL injury. The majority of ACL injuries occur during landing from a jump or sudden deceleration where muscular strength imbalances occur between the quadriceps and hamstrings; the quads tend to generate more strength than the hamstrings during jumping and sudden deceleration.

3.      Hormonal changes with the onset of puberty may cause joint laxcity due to the its effect onligaments.


The training protocol used in my training facility consists of a 4 step process that is used to help improvethe athletes movement patterns, address any muscular strength imbalances, and improve the core strength and endurance of the athlete. This protocol is based on my experience and education as a Trainer/Coach, and volleyball dad. It is very important that if you believe that your athlete is at increased risk to sustain a Anterior Cruciate Ligament (ACL) injury please contact us to schedule a movement assessment. The plan should be somewhat generalistic in its design because of varying degrees of structural dysfunction, muscular strength imbalances in the lower region of the body, “irregular” movement patterns, and because everyone moves bio-mechanically different.

 For more information please refer to the link below.





 -Jump-land characteristics and muscle-strength development in young athletes: a gender comparison of 1140 athletes 9 to 17 years of ageAm J Sports Med. 2006;34(3):375-384

- US National Library of Medicine National Institutes of Health; Natalie Voskanian corresponding author Department of Orthopaedic Surgery, University of California San Diego, 350 Dickinson St., #121, San Diego, CA 92103-8894 USA