ACL Tears and Injuries – The What, The Why and The How

Everything You Need to Know About ACL Tears

DR. BRUCE JOSEPH BUCKMAN, PT, DPT

You no longer have to be an avid sports fan to hear about the ACL any more. If you are a parent of a young athlete, a recreational athlete, or weekend warrior, I would surely bet that you have heard of this ligament and its injury epidemic. In our practice, ACL injuries are becoming more common than ever before, with age ranges from children of 12 years old to active adults of all ages. But why? Why are ACL tears in athletes becoming more and more common?

We will get there, I promise.

But first… a little background. What is the ACL?

The ACL is one of the four main ligaments of the knee, along with the Medial (inside) Collateral Ligament, Lateral (outside) Collateral Ligament, and Posterior Cruciate Ligament that connects and stabilizes the femur (thigh bone) to the tibia (big lower leg bone) and fibula (small lower leg bone). As a general rule, ligaments prevent or restrict motion to specific joints. The motions they restrict are determined from their origin and insertion.

  • Collateral Ligament
    • Collateral ligaments are outside ligaments, as seen below. These ligaments prevent valgus and varus (side to side) stresses to knee
  • Cruciate Ligament
    • Cruciate ligaments are found deep in the knee joint. The Anterior (front) cruciate ligament and Posterior (back) Cruciate Ligament cross in an ‘X” pattern to prevent front to back sheer stresses on knee joint.

The ACL, specifically, prevents anterior (or forward) translation, and internal rotation of the tibia on the femur. In other words, the ACL also prevents lateral rotation of the femur on the tibia.

How does the ACL play a role in my daily life?

Accelerating, decelerating, reacting, turning, twisting, and jumping, occur in almost every sport, and with these motions, our ligaments, along with muscles, prevent our joints from moving in unwanted or injury susceptible directions. However, when our muscles are broken down, our bodies are fatigued or malnourished, and our minds are not focused on the demanding task at hand, we put ourselves at risk for injury. Now, these are not the only reasons why ACL tears occur, but the fact is that an estimated 70% of ACL tears are sustained through non-contact mechanisms; the remaining 30% result from direct contact. This means, that 70% of the time, we cannot blame the contact sport, or another person for causing us injury.

So here are some facts:

  • The majority of ACL injuries (70%) occur while playing agility sports, most often reported in basketball, soccer, skiing and football.
  • ACL tears are most prevalent in patients 15-45 years old.
  • Female-male ACL tear ratio has been reported to be as high as 9:1 by NCAA statistics.

To explain the reason for females being nine times more likely to sustain an ACL injury than males, please see Figure 1. But, what else goes into that 70% non-contact number?

Fatigue

As touched on earlier, mental and physical fatigue can play an overwhelming role in injury. The concept of “overuse” is an educational piece for not only athletes, but many parents as well. Parents, think back to when you were growing up… what sports did you play, what seasons did they occur in, how many of your teammates had ACL injuries?   Many of the athletes whom I encounter in my practices who have had or are currently rehabilitating from an ACL tear report that they are a single sport athlete and play that sport all year round, on different teams possibly even at the same time. While not bad to build skill, our bodies need time rest, muscles time to recover, and minds to mentally decompress. Are the young athletes today, achieving this?

 The warm up and cool down

 The importance of the warm-up and cool-down cannot be overstressed. A warm up, should consist of active or dynamic movements that prepare and simulate game or practice-like situations, yes even contact movements. These movements and activities should aim to increase heart rate, initiate perspiration, and effectively warm up our bodies for the sport specific activities to come. Without a proper warm up, our bodies, muscles and joints are not properly acclimated to weather, external/environmental factors, or stretch/stress to come. A cool down should consist of static stretching and or foam rolling along with proper nutrient replenishing to allow our muscles, and minds to re-acclimate to normal.

 Finally, does field turf increase risk for injury?

The quick answer is that the jury is still out. While multiple research studies have been conducted, researchers have not found substantial evidence for or against field turf. Natural grass can yield many different surface types depending on the weather, while turf does not “give” as much as soil. My recommendations? When playing on turf, use a low cleat, to prevent planted feet from getting stuck when performing cutting, twisting, or jumping motions.

Stay tuned for Part 2 of this series, where I will talk about a few exercises for ACL prehabilitation or rehabilitation.

 Figure 1: Sex Differences in Females Compared to Males

 

Anatomical Differences Muscular and Neuromuscular Differences Laxity and Range of Motion
Wider Pelvis Diminished muscular force Greater range of motion
Increased flexibility Dependence on quadriceps muscle for stability Genu recurvatum (knee hyperextension)
Less-developed ACL Longer time to develop force Increased knee laxity
Smaller ACL in size Longer electromechanical response time Increased hip mobility/rotation
Increased genu valgum (knock knee position)
Increased medial tibia rotation

Wilk, K.E; Arrigo, C. Rehabilitation after anterior cruciate ligament reconstruction in the female athlete. Journal of Athletic Training 1999;34(2):177-193

References

THE FIRST SNOW IS UPON US, SO HERE ARE A FEW TIPS:

 

Now that the snow is obviously here, I want to make sure you protect yourselves from getting hurt.  

A recent poll points to snow shoveling as the leading cause of back and neck pain during the winter months. “Chiropractors are finding that some patients experience back and neck pain as a result of improper snow shoveling technique,” said Dr. Dennis Mizel, President of the Ontario Chiropractic Association. “Improper technique can be anything from bending at the waist instead of the knees to throwing snow instead of pushing it. When you combine improper technique with the average weight of one shovelful of snow (five to seven pounds) it becomes even more evident that this is a serious problem for both adults and the children who help them.”

We find at The Spine and Health Center of Montvale that back problems always surface in patients during the winter, especially those who are not used to participating in challenging physical activity on a regular basis.  Activities that require exertion that is more than someones normal daily routine like as winter sports or pushing stuck cars can cause back injuries. However, snow shoveling is the number one reason patients present with back pain in the winter.

 

Don’t let winter be a pain in the back – ‘Lift light, shovel right.’ Here are a few things to help prevent you from getting hurt:

1. Warm-up. Before beginning any snow removal, warm-up for five to ten minutes to get the joints moving and increase blood circulation. A good warm-up should include stretches for the back, shoulders, arms and legs. This will ensure that your body is ready for action.

2. Don’t let the snow pile up. Removing small amounts of snow on a frequent basis is less strenuous in the long run.

3. Pick the right shovel. Use a lightweight push-style shovel. If you use a metal shovel, spray it with Teflon first so snow won’t stick.

4. Push, don’t throw. Push the snow to one side and avoid throwing it as much as possible. If you have to throw, avoid twisting and turning – position yourself to throw straight at the snow pile.

5. Bend your knees. Use your knees, leg and arm muscles to do the pushing and lifting while keeping your back straight.

6. Take a break. If you feel tired or short of breath, stop and take a rest. Stop shoveling immediately if you feel chest or back pain.