ACL Injury: What you need to know.

ACL Injury: What we learned from an orthopedic surgeon and two sport-certified specialists from Langford.


For those of you who attended our ACL workshop in August (and there were a TON of you) thank you!  We are so glad we get to share our knowledge with our community. For those of you who missed it, here are a few things we shared.


What is the ACL?

The ACL (Anterior Cruciate Ligament) is a ligament which helps hold your knee together.  A ligament connects bone to bone (as opposed to a tendon, which connects tendon to bone).  The ACL connects your femur (thigh bone) to your tibia (shin bone), and it does so in a way that keeps you from hyperextending or rotating your knee certain ways.  It acts in concert with other ligaments, like the PCL and MCL, with the meniscus, and with the muscles of your leg to control the motion of your knee as you move.

How does an ACL tear?

Usually, an ACL tear happens during a pivoting motion, a hyperextension of the knee, or what we call a valgus force (when the knee drops in compared to the foot).  The biggest predictor of ACL injury is actually history of previous ACL reconstruction (on the same knee or opposite knee) or even previous injury of any kind, especially an ankle sprain.  ACL injuries often happen without contact, but can happen when someone hits the outside of a player’s leg, which drives the knee inward. Football, soccer and basketball players are at higher risk of injury, and women are more likely than men to tear an ACL.  One of the things we look at as physical therapists is how a player jumps and lands.

Photo by janulla/iStock / Getty Images
Photo by janulla/iStock / Getty Images

Here is a video showing poor landing mechanics.  The first video shows landing in less of a squat, with straighter legs.  The second shows knees collapsing in together. The third demonstrates landing on heels instead of the balls of the feet, and landing with toes turned out.

What can you do to reduce your risk (or your kid’s risk) of injury?

We will have another blog coming up with some specific exercises, but remember a few things about ACL injury prevention.  First, strengthening should happen progressively over time, adding about 10% per week in intensity, duration and/or resistance.  Emphasis should be on hamstrings (especially for women), gluteal muscles, and core. In addition to strength, we need to train movement control, which is how we use our strength to move our bodies through space.  Exercises that help with motor control include step-downs, jumping and landing drills, single leg jumping drills, and single leg balance drills.

There are a few injury prevention programs with some research behind them, including the FIFA 11+ program for soccer.  This is done as a warmup and includes s15 exercises that emphasize core stabilization, eccentric thigh muscle training, proprioception and dynamic stabilization (movement control), and plyometric exercises (jumping and landing).  You can learn all about the FIFA 11+ HERE.

Lastly, there is increasing evidence that early sport specialization can increase injury risk for athletes.  This means that kids really shouldn't compete in only 1 sport, nor should they play a primary sport for more than 8 months each year.  Don't worry about performance--there is NO evidence that specializing early improves performance.  In fact, most elite-level athletes don't specialize until late adolescence, and the majority of Division 1 athletes were not highly specialized at any point during their high school careers.

What if I already tore my ACL?

Dr. Dustin Richter, MD taught us about ACL injury risk, surgical considerations, and post-surgery care. Everyone should know that surgery is elective, not required.  Note that surgery is not meant to treat pain or prevent arthritis. Rather, the goal of surgery is to provide STABILITY to the knee so you can keep doing the activities and sports you want to do without your knee giving out.  If you can return to play without this type of instability (knee giving out), you may not need surgery.

If you choose not to have surgery, you should work with a physical therapist to strengthen and train your movement control, progressing to sport-specific exercises in order to meet your goal to return to play without knee instability.  At Langford Sports & Physical Therapy, we have two sport-certified physical therapists who went through rigorous residency programs in order to gain a TON of knowledge and experience with sport injuries and surgeries. All of our physical therapists work with these two to provide the most effective treatment possible, so no matter which PT you choose to work with, you will get the best care possible.

If you choose to have surgery, here are a few things to remember.  Healing time of an ACL graft (a new ACL) takes at least 3 months, and your new ACL will be weakest between 8 and 12 weeks after surgery.  This is super important to know, as you will be limited during this time in order to reduce your risk of re-injury while you heal. Timelines for return to sport may vary, and you should always work with your surgeon and physical therapist to determine your readiness, but Dr. Richter told us that, generally, returning to jogging in a straight line can start about 3 months after surgery, more pivoting and cutting can happen around 5-6 months, and return to sport should happen around 9-12 months.  We used to return much earlier, but recent literature suggests waiting until 1 year to allow proper healing and training is best.

How do I know if I’m at risk?

We offer sport injury screenings at MoveTru with our certified athletic trainer, Julie Holt, ATC…  Contact us today if you or your sports team would like to go through this testing to see what you need to do to reduce your risk of injury.  If you've already torn your ACL and need a good PT, contact us to schedule today.

Now what?  Keep up to date and catch the details you missed with our blog.

In case you were overwhelmed by the amount of information that was presented, follow our blog online or find us on Apple News for regular updates. Our next article will have some exericises you should include in your training program to reduce your risk of injury.

Thank you again, and please be sure to swing back in, either to see a PT for an injury, work with Julie for an injury risk screening, or to try a MovNat class or run on the AlterG.