Monday, March 30, 2020

Psychological Measures for Return to Sport Following ACLR - Part IV

Over the course of this blog series, we have been discussing Kinesiophobia (fear of movement) that is sometimes associated with athletes who have an ACL reconstruction.  During last week's discussion, we pointed out some objective measures we see in our athletes who demonstrate higher levels of kinesiophobia.  The two main things we see are:

  • An increase in lateral shift or shift of body weight over to the non-involved limb during squatting motions.  Noehren et al Am J Sports Med 2018 found similar findings in their study where they found athletes with higher levels of kinesiophobia unloaded the involved limb during drop jumps.   The following video describes lateral shift in more detail.

  • An increase in speed of valgus during single limb activities.  What we see in these cases is athletes who report higher levels of kinesiophobia fall into larger magnitudes of valgus at much higher rates of speed.  The video below is an illustration of an athlete who falls into a large degree of valgus at a higher rate of speed during single limb exercises.  


The question is, is it the chicken before the egg or the egg before the chicken.  In otherwords, is it the kinesiophobia that results in the lateral shift to the uninvolved side and lost of control of the limb speed and magnitude OR is it the lateral shift and high speeds that results in the kinesiophobia.  Although we don't know that answer, we do have our thoughts and theories on.  

That said, what we do know is that we can train an athlete to correct a lateral shift and we can train them to control the magnitude of motion of the knee in the frontal plane and the speed at which it occurs.  What we do know, is that when we do correct both of these things that kinesiophobia is dramatically reduced and in most cases completely eliminated.  

There are a lot of ways to correct a lateral shift, increase control of frontal plane motion and speed of motion.  The exercises described here are just a couple of examples of ones that we do.

Lateral Shift
The first step to correcting a lateral shift is first measuring the degree of lateral shift.  We do this with a 3D wearable sensor, called DorsaVi.  The video below is an example of how we do this in college athletics.  



There are other ways of doing this with 2D (video) technology.  Filming the athlete from the posterior view, drop a plumb line at midline from the cervical spine to the sacrum.  During the squatting motion, the hips should remain relatively equal distance from that plumb line.  If not, then the athlete is shifting their weight to one side which alters loading and recruitment patterns.  Measuring this gives us a baseline to start from.  In addition, this also provides us a visual cue we can use to show the athlete what a lateral shift is.  This is critical to gaining their understanding of and in helping them correct the motion.  

Once the athlete understands the lateral shift, we then can start working on correcting it.  There are couple of ways we address this.

  • Squatting on a force plate.  Now this may sound super expensive and out of reach of most clinics, however we use a new technology on the market call the Boditrak.  The video below demonstrates the Boditrak.  In this example, we would use this a biofeedback during the squatting motion.  We bluetooth this to a TV placed in front of the athlete.  This allows the athlete to see what the weight distribution is between the limbs.  If a lateral shift occurs, the athlete would see this demonstrated in the display and could easily correct this after multiple repetitions.  




  • Squatting with video.  Similar to what is described above, we can do the same thing without the force plate and while doing a live feed with a video.  In this scenario, we film the athlete from the posterior view and bluetooth this to a TV placed in front of the athlete.  This way, the athlete can perform the squatting motion all while visually correcting their lateral shift.
  • Squat Neuromuscular Re-education - this is another technique we will do to help correct a lateral shift.  This is a little more of an aggressive form of training which we will describe in more detail in our next blog.  
In our opinion, a lateral shift must be corrected.  All too often we see athletes that are returned to play or performance training who still demonstrate significant lateral shifts.  The problem with this is that the same athletes will then carry this lateral shift over when doing squats under load.  So, if they demonstrate a 2" to 3" lateral shift under body weight, they tend to demonstrate the same thing when performing squats with 200 to 300#.  Although this is bad under normal bodyweight conditions, this is really bad when done under higher loads.

Next week, we will continue this discussion on how to a how to correct a lack of stability (motion and speed of motion) in single limb activities.  We hope you have enjoyed this discussion and stay tuned as we continue the discussion.   #ViPerformAMI #ACLPlayItSafe



Dr. Nessler is a practicing physical therapist with over 20 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment and ACL injury prevention.  He is the founder | developer of the ViPerform AMI, the ACL Play It Safe Program, Run Safe Program and author of a college textbook on this subject.  Trent has performed >5000 athletic movement assessments in the US and abroad.  He serves as the National Director of Sports Medicine Innovation for Select Medical, is Vice Chairman of Medical Services for USA Obstacle Racing and movement consultant for numerous colleges and professional teams.  Trent is also a competitive athlete in Brazilian Jiu Jitsu. 

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