Monday, June 29, 2020

Neuroplasticity and ACLR Rehabilitation - Part IV

Last week, we started our discussion talking about explicit strategies (internal focus on the movement itself) and implicit strategies (external focus on the movement effect).  These are types of training or verbal instructions we give to patients during performance of rehabilitation exercises.  What the studies show is that implicit strategies have a better carry over to sport and create greater neuroplastic changes in the higher centers (specifically the motor cortex, somatosensory area and cerebellum).  These types of changes reduces risk for reinjury with return to play as these are the patterns the athlete resorts to during functional activity. 

In our last discussion, we talked about the difference between these two strategies and when using one form of training or instruction may be indicated versus another form.  We also discussed how your verbal instructions can significantly alter movement and I gave the specific example of how this can alter the movement when performing a functional movement assessment. 

When looking at how this might impact our training, we can look at the study by Benjaminse et al Phys Ther Sport 2015.  In this systematic review, the authors looked a different forms of training.  For this example, we will use the ACLR specifically and doing single limb training.  Based on the data we have collected on over 18,000 athletes with the ViPerform AMI, we know control of both the magnitude of frontal plane motion and speed of valgus during single limb performance is critical.  If athletes can control this during training and functional activities (sports) then we know we have impact or mitigate some of the risk with them returning to play.  Based on the neuroplasticity research, there are some innovative ways do accomplish this.

Using a single leg balance on an unstable surface as an example.  In this exercise, I want the athlete to control the magnitude of frontal plane motion and speed of that motion.  In exercise A, I am placing a mirror in front of the athlete and asking them to control their knee,  Don't let the knee go in toward midline.  In this instance, I am using an internal focus, focusing on the movement.  In exercise B, I give the athlete a PVC pipe and ask them to keep the bar horizontal.  In this example, I am using external focus, focusing on the result of the movement. 


What we see here is the result.  In exercise A, although the athlete is successful at controlling her frontal plane motion, she also has a lot of hip motion occurring.  At the same time, what we find (or according to the research) is that this does not carry over as much to her actual movement in sport.  In exercise B, we see that not only is she maintaining better alignment at the knee but her hip position is also much better.  Considering this may have better carry over to sport, then this might be a strategy that I employ.  At the same time, I can add additional stresses to the system to make her maintain that positioning and posturing while specifically targeting her areas of weakness.  If you go back to our blog where we talked about rapid neuromuscular response (RNMR) training, you can see some specific exercises targeting that. 

In the next example, using a single leg squat.  In exercise A, I am placing a mirror in front of the patient and asking them to perform a single leg squat and asking them to keep their knee over their toe and not allow their knee to go in towards midline.  This is again a form of internal focus where I am focusing on the movement.  In exercise B, I am placing a cone in front of the athlete and asking them to reach toward the cone with their knee.  This is a form or external focus or a focus on the result of the movement. 


Again, what you see in exercise A is that the athlete, although better, still has some increase in frontal plane motion at the knee and has a lot more motion at the hips.  In exercise B, we not only have better control of frontal plane motion but also much better positioning and posturing of the entire kinetic chain and core. 

Again, these are two examples but you can see how internal focus versus external focus can be applied with our training.  That said, I want to be clear.  Although the research does say that external focus does have a better carry over to sport and functional activity, as with all training, I believe there the need to use both forms of training.  Similar to OKC and CKC exercise.  Research supports use of CKC exercise but I strongly believe that both OKC and CKC exercise have a place in rehabilitation and performance training.  To focus on just one, I think you miss part of the picture.

I hope you found this valuable and next week, we will continue this discussion.  Specifically, next week I will talk about a device we are using in our ACLR rehab that addresses all this as well as some of the results we are seeing with.  As always, I appreciate all our followers and hope you find this useful in your practice.  If you do, please follow me on instragram @bjjpt_acl_guy and Twitter @acl_prevention.  I also just launched a new website, www.drtrentnessler.com.  My vision is to create a movement revolution in the world of ACL rehab.  Check it out, hear more about my story and where we are headed.  Train hard and stay well.  #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,  ViPerform AMI RTPlay, 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 also a Brazilian Jiu Jitsu purple belt and complete BJJ/MMA junkie. 

Monday, June 22, 2020

Neuroplasticity and ACLR Rehabilitation: Part III

Last week, we discussed in detail the Grooms study which showed that there are in fact some changes that occur in the higher centers in the brain after an ACL injury.  As much as we think our typical rehabilitation will address this, the reality is and the studies show, these deficits remain unless they are specifically addressed.  These remaining deficits may be one additional factor that leads to increased reinjury rates post ACLR. 

When talking about neuroplasticity and how do we effectively train to improve these deficits that occur, you will hear some talk about the constrained-action hypothesis.  This hypothesis suggests that an internal attentional focus could be negative on an athlete, causing them to interfere with their body's natural movements.  In other words, there are two types of focus, internal focus and external focus. 

  • Internal focus is where there is a focus on body movements.  Typical instructions we give that drive this type of focus is - don't let your knees go in toward midline, don't let your knee go over your toes, etc.
  • External focus is where there is a focus on the movement effect.  Typical instructions we give that drive this type of training is - when you jump, try to touch the hanging ball, when you jump, try to jump past the line.
Benjaminse et al Knee Surg Sports Traumatol Artho 2011 showed that explicit strategies require an internal focus on the movement itself and is less likely to transfer to the sport itself.  However, Implicit strategies require external focus on the movement effect and are more likely to transfer over to sport.  At this point, you may be saying to yourself, well that is great but what the heck does that mean?  Benjaminse et al Phys Ther Sport 2015 performed a systematic review demonstrating the effect of internal focus and external focus instructions on jump landing technique.  What the authors found was that external focused instruction resulted in better motor performance and movement technique than internal focused instruction.  

Based on all this, there are some major takeaways from what we have learned so far.  
  1. Be mindful of the instructions we use when we are instructing athletes
  2. Verbal instructions have a direct effect on motor performance 
I am going to digress here for a moment but we will return to talk about some specific training applications to training.  We have noticed something similar when doing our 3D movement analysis.  When providing instruction to the athlete,for example, on the full squat test, we find the more verbal instruction we give to the athlete the less natural their actual movement is.  
  •  Example 1 - I ask the athlete to perform a squatting motion to 90 degrees with the feet shoulder width apart while keeping their chest up and not allowing their heels to come off the floor.
  • Example 2 - I demonstrate a squat and then ask them to repeat the motion.
In example 1, I will get the motion that I described.  This may not be the natural motion the athlete uses when doing squats but rather their interpretation of what I have described.  In example 2, I will get a squatting motion that is more natural to what the athlete typically does.  In this case, where I am attempting to get a 3D baseline movement assessment, I am want to get their natural motion.  Therefore, I use very little instruction and more demonstration (example 2).

That being said, if you go purely by the research, this would suggest that we don't ever use some form of internal focus training.  Personally, I think there is a place for that.  If you have someone that has a profound dynamic valgus that they demonstrate during all high level functional activity then I am going to work on that.  I will do some targeted training where I will have them control the frontal plane motion of their knee.  I think this is important to build some foundational strength so that when we move to more aggressive sport specific movements that they are able to control that motion.  When I get to that level of training, they then have the base strength and endurance to maintain frontal plane control at which point I will move to some more of an external focus.  

Next week, we will discuss this topic a little more in depth and get into some specific training ideas based on what we are learning.  As always, I appreciate our views and hope you find this useful.  If you do, please follow me on instragram @bjjpt_acl_guy and Twitter @acl_prevention.  I am constantly posting the latest research in injury prevention and sports medicine.  Don't miss out and please share with your colleagues, athletes and training partners and again follow us on instagrm @ bjjpt_acl_guy and twitter @acl_prevention.  Train hard and stay well.  #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,  ViPerform AMI RTPlay, 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 also a Brazilian Jiu Jitsu purple belt and complete BJJ/MMA junkie. 

Monday, June 15, 2020

Neuroplasticity and ACLR Rehabilitation - Part II

Last week, we started our discussion about neuroplasticity and how there may be changes in the higher centers of the brain that occur following an injury.  One of the studies we mentioned was the study by Grooms et al J Orthop Sport Phys Ther 2017.  The purpose of this study was to compare differences in brain activity during knee flexion and extension exercises in those that had an ACLR compared to matched controls.

Methods:
15 athletes who were average of 38 months post ACLR where compared to 15 matched controls.  Healthy matched controls were matched on age, sex, height, mass, extremity dominance, education level, sport participation and physical activity level.  All subjects filled out an IKDC (international knee documentation committee) questionnaire. 

Each subject had a functional MRI performed while they performed a unilateral leg extension/flexion exercise depicted below.  Each subject performed the task for 30 seconds rested 30 seconds and performed 4 blocks of movement and 5 blocks of rest.  Brain activity was mapped during the course of the exercise and comparisons to matched controls were made.



Conclusion:
ACLR patients had significantly lower scores on the IKDC when compared to matched controls.  The ACLR group had increased activation in the contralateral motor cortex, contralateral lingual gyrus and ipsilateral somatosensory area.  There was also diminished activation in the ipsilateral motor cortex and ipsilateral cerebellum. 

What this tells us is that there is altered activation in regions of the brain that are responsible for sensory, motor and sensory-visual-spacial processing.  Obviously these are key areas and proper functioning is a key part of successful return to sport performance as well as mitigating injury risk with return to sport.  If you consider the two studies I spoke about last week, this may be one reason we still see these biomechanical deficits so far out from surgery despite the fact that they have had surgery.  The fact that these subjects are 38 months post op, tells you that these deficits DO NOT self correct. 

One perfect example is a lateral shift.  As much as we think we catch it, correct it and prevent it in our ACL rehab, the reality is that there are a lot of therapist that do not.  The fact that we see this in mass physicals with college athletes who had an ACLR back in high school some 3 years ago tells us we did not catch it then.  The reality is, we have to do ACL rehab better.  Addressing the neuroplastic changes is a perfect example.   

Next week, we will take a look at a case study of an athlete with an athlete that is 11 months post ACLR.  The athlete was being evaluated for RTSport and we will see what the results were.  We will follow this up by some motor learning studies with ACL rehab to get some specific examples of exercise techniques we can deploy as a part of rehab.

Have you followed my instragram @bjjpt_acl_guy lately?  If not, you are missing out.  I am constantly posting the latest research in injury prevention and sports medicine.  Don't miss out and please share with your colleagues, athletes and training partners and please be sure to follow us on instagrm @ bjjpt_acl_guy and twitter @acl_prevention.  Train hard and stay well.  #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,  ViPerform AMI RTPlay, 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 also a Brazilian Jiu Jitsu purple belt and complete BJJ/MMA junkie. 

Monday, June 8, 2020

Neuroplasticity and ACLR Rehabilitation

One of the most challenging aspects of treating athletes who have had an ACLR comes at the conclusion of rehabilitation when we are attempting to make that final return to sport decision. Throughout the rehab process, we do everything we can to ensure that the athlete is physically and mentally ready for return to sport. We hope that the training methods we have implemented have prepared them for this. But what if I told you there is an aspect that we typically miss.

Have you heard of neuroplasticity?  Defined, neuroplasticity is the ability of the brain to form and reorganize synaptic connections, especially in response to learning or experience or following injury.  This has become an area of increased focus in ACLR because we know there are changes that occur in the higher centers (brain) after an ACLR.  If these changes are not addressed as a part of our rehab, then they can remain and increase the athlete's risk of reinjury with return to sport (RTSport).  At this point you may be saying to yourself, not my patients.  With the functional training that I do, by the time they are ready for RTSport, we have addressed this.  Have you?

Some recent studies have highlighted a sobering fact.  We are not as good as we think we are.  King et al Am J Sport Med 2019 performed 3D motion capture on 156 athletes that were 9 months post op ACLR and compared those to healthy controls.  The subjects performed:

  • Bilateral vertical drop jump test
  • Single leg vertical drop jump test
  • Single leg hop for distance
  • Planned and unplanned change in direction task
What the authors found was there was an asymmetry in loading in the bilateral vertical jump test and greater asymmetries in single limb testing.  Considering all these athletes had gone through rehabilitation and were progressed for RTSport, there was obviously something missing in the rehab process that allowed this degree of asymmetry to continue to exist.  

When you look at athletes who have gone back to sport and who are doing some kind of strength and conditioning with the team, then surly this must be corrected and resolved.  Ithurburn et al Am J Sport Med 2019 took this one step further and looked at athletes who had RTSport and were 2 years out post ACLR.  In this study, the authors looked at 64 male and female athletes and did 3D motion capture during bilateral and single limb vertical jump testing.  What the authors found was bilateral vertical jump test significantly improved with improved symmetry but single limb vertical drop jump test still demonstrated significant asymmetry.  

So despite going back to their normal routine, sports, sports training, weight lifting, etc, there still remained a significant deficit that puts that athlete at a greater risk of reinjury.  So what are we missing?  One, we need to do a better job of testing "biomechanical" factors throughout the course of rehab to ensure the interventions we are doing are in fact positively changing these.  But two, we need to make sure we are addressing the neuroplastic changes that occur.  

Neuroplasticity also known as brain plasticity or neural plasticity is the ability of the brain to change throughout one's lifetime. We know, for example, in stroke patients, that the brain has the ability to adapt and change as a result of the neural insult to the brain and can remap neural pathways so that non-damaged areas can take on some of the function of the damaged sections. That is neuroplasticity. In neuro rehabilitation settings we know this and can deploy certain techniques that will aid in this facilitating this process or neural adaptation in the brain. This aids to improved function despite the initial neural insult. In sports medicine, we rarely think about the changes that occur in the higher centers (in the brain) with an orthopedic injury.

However, next week, we will start looking at some recent studies, like the study by Grooms et al J Orthop Sport Phys Ther 2017 which highlights some of these neuroplastic changes that occur post ACLR.  This will lead into some specific training and programming we can do to change.  Stay tuned as I am super excited to share with you.

Have you followed my instragram @bjjpt_acl_guy lately?  If not, you are missing out.  I am constantly posting the latest research in injury prevention and sports medicine.  Don't miss out and please share with your colleagues, athletes and training partners and please be sure to follow us on instagrm @ bjjpt_acl_guy and twitter @acl_prevention.  Train hard and stay well.  #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,  ViPerform AMI RTPlay, 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 also a Brazilian Jiu Jitsu purple belt and complete BJJ/MMA junkie.