ACL tears Disproporitionate rates

Females tear their ACL, anterior cruciate ligament, up to 10 times more than their male counter parts from non contact injuries.
This means that they are just running along, cutting, pivoting, and landing and boom! They are on the ground.  There are approximately 22,000 ACL injuries in female athletes each year from high school to collegiate sports.  1/10 girls that compete collegiately in any sport(not just jumping, cutting and pivoting sports) will tear their ACL prior to graduation.  That is crazy.  It is especially crazy when it is preventable.

The Cause:  Different biomechanics.  Females demonstrate different landing and decelerating patterns than men.   Females have tendency to land with their feet flat and heels hitting the ground.  This also occurs with less flexion of the hips which causes excessive force through the knees.

As a female hits puberty the long bones of the leg the femur(thigh bone) and tibia(shin bone) grow as they begin to ascend to their adult height and skeleton.  However this occurs with an increase in estrogen and a decrease in testosterone.  A boy typically sees a significant spike in testosterone as their limbs begin to grow.  This in turn creates an increase in the ability to develop more muscle tissue and control the movement of the now increasing long levers of the tibia and femur producing torque at the knee.

The knee is a hinge joint primarily but has 6 degrees of freedom.  It can move forward and back, side to side and rotate each direction however most of the motion is front to back.  The joints in which most of the rotatory motion occurs are at the ball and socket joint of the hip and the pseudo ball and socket joint of the ankle.

When the hip and knee joint are not controlled during dynamic movements, the excessive rotational torque is distributed to the knee tearing the ACL.  There are 2 and sometimes 3 bundles to the ACL which is actually twisted and runs at an angle. It is designed to resist some rotational and angular forces but easily tears in the position of dynamic knee valgus, which you see above with opposite side hip drop, thigh bone and knee medially deviating and rotating internally.  This is often seen with pronating of the foot and ankle or collapsing of the medial arch of the foot.
 

Females also demonstrate less of an ability to fire their hamstrings at high speeds.  During slow speeds they are equal to boys but at faster speeds they are deficient.  This makes sense.  The ACL is a restraint to anterior tibial movement and tears with excessive anterior tibial translation.  The lachman test, pictured above, is the gold standard for testing the ACL in which anterior force is exerted manually on the tibia by an examiner to assess integrity of the ACL.

 When the hamstrings contract, they exert a posterior pull on the tibia which allows the knee to flex or bend as pictured above.  Females typically tear their ACL during high velocity movements such as decelerating, cutting and landing from a jump.  This suggests that the nervous system is not sending the appropriate message to fire the muscles to stabilize the knee quickly enough.

The best part about this is that bioemechanics and nervous system responses are easily trainable.  Most ACL injury prevention programs have a greater than 90% success with participants not experiencing these devastating injuries.

Females are not built like males and they need specialized training.  They at least need to be screened to determine if they have high risk biomechanics.  I often say that female athletes are the most neglected population in the country.  How can we allow 22,000 of our sisters, daughters, cousins, nieces and friends to experience this nearly preventable injury each year.

In conjunction with the Sport Science Lab, Revolution Physical Therapy has an answer for our young ladies.  I am now offering a free screening for any female who would like to know if they are at risk.  I feel  so strongly about this that I am willing to help people for free.  If you don't know if you or your loved one is at risk, then how can you know how to prevent it.  It's like smoking cigarettes, at some point a smoker will get health problems.  Undeniable.  If you are a female athlete playing sports involving cutting, pivoting and jumping  without the appropriate training, you are eventually going to have a knee problem.  This could be season or career ending.  Thousands of college bound females lose their scholarships every year from indifference, denial and neglect..  Time to make a change.  Join the Revolution!

Please contact me or my office at 724.591.8005

Lyneil Mitchell, DPT
drlyneil@revolutionphysicaltherapy.com
www.revolutionphysicaltherapy.com


20630 Route 19 Suite 102. Cranberry Twp, PA 16066