Monday, December 5, 2016

Challenging the Status Quo - template

Over the course of the last couple of weeks, we have been providing some clinical commentary on what we have learned in 20 years of clinical practice and over 15 years in movement assessment.  Obviously, we can't encapsulate everything we have learned in a blog or two but we can provide some insights.  We have begun to discuss in detail, over the last 2 weeks, that we need to recognize where the flaws are in our current ways we assess so we can do things better.
  
During the last 2 weeks we went into depth on some movements we can look at and what the research tells us about how we should look at them.  Assessing these movements as described in the literature should and will guide our specific interventions.  At the beginning of this section, we highlighted what we know are well documented movement risk factors.  As a point of reference, these are:
The above referenced articles are only a few of the large number of studies showing the same thing. So although there is only one referenced here, these are some of the more current ones that have been done over the last 10 years highlighting the same risk factors.  Based on the literature, we know several things.
  1. Frontal plane motion of the knee greater than 10 degrees in motion is bad!  The larger the magnitude of this motion, the worse it is.  An athlete that has 20 degrees of frontal plane motion is at greater risk than an athlete with 10 degrees of frontal plane motion.
  2. Speed at which this motion occurs is a risk factor!  An athlete that has10 degrees of motion that occurs slowly is at less risk than an athlete that has 10 degrees that happens very fast.  Although we have not published this, some guidelines we see are: 
    •   In a single leg squat if valgus occurs at >20 degrees per second, then the athlete is at greater risk
    • In a single leg hop if valgus occurs at >100 degrees per second, then the athlete is at greater risk
  3. >20% variance in single limb symmetry is bad!  Keep in mind, an athlete can move equally bad on both legs so although, in this scenario, they are symmetrical, it is still bad.  But overall, a >20% variance is bad.  Larger the variance, the greater the risk.
  4. Asymmetry (shifting weight to one side) during the squatting motion is bad!  Whether you call it a lateral shift or lateral displacement of the pelvis during a squatting motion, this has a direct impact on force attenuation and force generation.  The larger the asymmetry is during the squat the greater the risk is.   
  5. Inability to maintain core stability within 10 degrees is bad!  This should be assessed for the ability to maintain stability in flexion/extension and rotation. 
In addition to the above, we also know there are demographic risk factors that should be considered.  
 
Considering all the above, then we should take a look at the standard of practice for movement assessment in athletics.  Remember the intent is to question the status quo so that we can do what we do better.  At the end of the day, we are not concerned about offending people, but rather prevent more injuries in our athletes!  As such, most would agree the most commonly used movement assessment today is the Functional Movement Screen or FMS.  For those of us familiar with the FMS, we recognize that the research based risk factors noted above is not assessed using the FMS.  Looking at some of the specific movements:

  • Overhead squat - assesses several factors but is not assessing lateral displacement of the pelvis or lateral shift
  • Hurdle step & In-line lunge - although they are measuring asymmetry of motion assessed with the FMS, it is not assessing magnitude or speed of frontal plane motion of the knee during SL performance or the asymmetry of this frontal plane motion.
  • Trunk stability and rotational stability test have little research support related to their correlation and core stability in sport.
In addition to the above, some additional challenges:

  • Fatigue not assessed.  Does 3 repetitions performed with each exercise give a true picture of what the athlete looks like in sport.
  •  Demographic risk factors not considered in overall risk rating.
  • Composite score of 21 is not sensitive enough to detect minor improvements in movement.
Considering the above, then the results of some of the current research is not a surprise.  Some of the current studies include:

  • Bardenett et al - Int J Sports Phy Ther 2015 - looked at the FMS as a predictive tool in high school athletes.  Of the 167 high school athletes that were assessed during the pre-season, the results showed the FMS was good at recognizing asymmetry in the movements tested.  But they found that the results were not a good at predicting injury.
  • Dorrel et al - J Ath Train 2015 - performed a systematic review and meta-analysis of research from 1998 to 2014.  What the results showed was that the FMS demonstrated low predictive validity for injury prediction and leading the authors to conclude that this should not be used for injury prediction.
  • Bushman et al Am J Sports Med 2016 - looked at the FMS as a predictive tool in active male soldiers.  Of the 2476 soldiers assessed, the FMS demonstrated low sensitivity and low positive predictive value.  This lead the authors to conclude this could lead to misclassification of injury risk in military personnel.  If they are assigned to hazardous duty as a result of this misclassification, it could potentially place the soldier at greater risk.
  • Frost et al J Strength Cond Res 2013 - did the FMS on healthy firefighters and scored each on the assessment.  This was followed 3 minutes later by performing the test again but just prior to testing each firefighter was instructed on what they were being scored on.  Each participant had an average of 2.6 point (12.4%) improvement in their overall score with just knowledge of how the test is scored. 
  • Wright et al Bri J Sports Med 2016 - in this clinical commentary based on the literature review showing a low sensitivity of 24% led the authors of this paper recommending that this should not be used for injury prediction or for making return to sport calls.
Despite all the above, the FMS has been instrumental in advancing what we know about movement and screening for risk.  The FMS and the developers behind it have been instrumental in the creating this shift to look more closely at movement.  As a result, the positive impact they have had on the field and injury prevention is immeasurable.  But as a science, we must advance based on what we know.  Consider, can we do it better?

We hope you enjoyed this week's commentary and hopefully it provoked some new thoughts.  Next week we will close this out with looking at not over complicating movement and raising the standard of practice. 


 
Dr. Nessler is a practicing physical therapist with over 17 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment.  He is the developer of an athletic biomechanical analysis, is an author of a college textbook on this subject  and has performed >3000 athletic movement assessments.  He serves as the National Director of Sports Medicine Innovation for Select Medical, is Chairman of Medical Services for the International Obstacle Racing Federation and associate editor of the International Journal of Athletic Therapy and Training. 

Monday, November 28, 2016

Question Status Quo - Part IIIb

Over the course of the last couple of weeks, we have been providing some clinical commentary on what we have learned in 20 years of clinical practice and over 15 years in movement assessment.  Specifically some clear conclusions which we have begun to discuss in detail.  These include:
  1. Movement is very complex and very hard for the majority of people to see and assess
  2. The standard of practice is often 5-10 years behind the literature and clinical advancements
  3. There is a strong correlation to improvements in movement efficiency and to mitigating risk of injury and improving athletic performance
  4. We need to recognize where the flaws are in the current ways we assess movement are so that we can become better at what we do
  5. Sometimes movement is just movement and we try to over complicate it
  6. The standard of practice or care, in my opinion, tends to be the standard of the lazy and status quo. 
Last week, we began to discuss the need to recognize the flaws in our current methodology and what can we do better.  Knowing the need for efficiency, we also made a couple of suggestions on movements we should assess quickly and how the research tells us we should look at.  Last week, we looked at the single leg squat and single leg hop in detail.  Today, we will expand on that.

Over the course of the last 2 decades, clinically, I have always felt the core was a key component to stability of the lower and upper kinetic chain.  Using the lower kinetic chain as an example, having a stable surface to pull on, it made sense the quads, hams, gluts, etc could then generate much more force than with an unstable core.  The analogy I always used in the clinic is sitting on a rolling stool is to have a patient pull on you without securing yourself.  They pulled on you and you roll.  Now repeat this and stabilize yourself so you don't roll.  How much more force can they generate pulling on you?  Why?  Because they are pulling on a stable surface.  This analogy applies to the ability of the quads/hams being able to generate more force when they are pulling against a stable surface.  At the same time, providing a stable surface also provides proper length tension relationships for the muscles of the lower quarter which has a direct impact on force production. 

Ironically, this has also been vetted in the literature in the last 10+ years.  Chaudhari et al Am J Sport Med 14 showed that professional baseball players who had poor core stability were 3 to 2.2 times more likely to miss 30 days throughout the baseball season.  These players reported more shoulder injuries than those players with a stable core.  Chaudhari et al J Strength Cond Res 11 also showed the impact improvements in core strength have on athletic performance.  In this study, they showed that pitchers who had improvements in core stability also had walked less players and less hits per inning.  Although it has not been vetted in the research yet, I would hypothesize that improvements in core stability also has a direct impact on pitching velocity.  There is also a correlation to core strength and lower kinetic chain injury risk.  Frank et al  Am J Sport Med 2013 also showed that improvements in core stability resulted in decreases frontal plane motion of the knee which decreases stress to the ACL.  We now know the impact this has on lower limb injury risk but what about performance?  Hoshikawa et al J Strength Cond Res 13 showed that improvements in core stability had an impact on vertical jump.  So based on the above, we obviously need to test the core.  So if we do test the core, what should we test or how should we test it?

Tong et al Phys Ther Sport 14 showed high EMG activity of the core during the plank test.  Looking back at the basics (Nordin & Frankel - Basic Biomechanics of the Musculoskeletal System) we know that 10 degrees of motion of the spine from neutral in flex/ext or rotation puts a lot of stress on the structures of the spine.  If this motion occurs under high loads associated with sport (which range from 4-8 times body weight) that this not only compromises the structures of the spine but also the lower kinetic chain.  Therefore, stability of the spine (within 10 degrees of flexion/extension and rotation) during this test is one thing that should be evaluated.  Norms for this test vary by age and Strand et al J Human Kin 14 have shown what some variations are by age.  For athletes, this should be a sustained position for 1 minute.  During this time, close attention should be paid to the stability of the spine in this position in the previously mentioned motions. 


Most people who perform the plank do it incorrectly.  The key to this motion is to ensure the hip and spine are in a neutral position.  As depicted here, training and testing in this position has a much better carry over to upright posturing and is a better indication of true stability in these neutral positions. 

In addition to the plank test, another test that should be considered is the side plank test.  Ekstrom et al J Orth Sport Phy Ther 07 showed highest EMG activity in the side plank was with the gluteus medius.  So the side plank is an excellent test for assessing the strength and endurance of the core and the gluteus medius.  Just as noted previously, this test should be assessed for the ability to sustain the position in neutral spine in lateral sidebending as well as rotation.  As stated previously, there are norms published for this test but for most athletes, testing this position should be done for 1 minute time.

The side plank, like the plank is often done incorrectly.  The testing position should be similar to what is depicted here in this picture.  All too often, athletes will position themselves in position that shortens the gluteus medius which will then limit the strengthening of this muscle.  Doing this during the test will decrease the reliability this will have to hypothesis about glut strength, especially in single leg stance and result in less than optimal training carry over to sport. 

*Note on Side Plank - over the course of the last 10 years in using this as a part of our testing with athletes, we have found some correlations that we have yet to see in the published literature.  One of those we want to highlight because this is critical to our interpretation and associated intervention.  Depicted here is what we term tibial drop.  The athlete (basketball player) is unable to maintain a neutral ankle position during this test.  This is most likely the result of ankle weakness and in this case, associated with a history of chronic ankle sprains.  If we had not been looking at the feet during a side plank position this would have been missed and the athlete would have scored low.  The hypothesis for this would have been weak glut medius.  The program that would have been implemented may have had some impact but think we would all agree not near the impact as if we addressed the foot/ankle weakness.

Over the course of the last couple of weeks, we have talked about what we should look at.  Hopefully the discussion on single limb testing and core testing provides some insight and guidance on where the literature is leading us.  Next week, we will close out this portion on the movement aspect by looking at the specific research related to some of the fallacies with current assessments we use, what the research tells us and how we can apply.



Dr. Nessler is a practicing physical therapist with over 17 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment.  He is the developer of an athletic biomechanical analysis, is an author of a college textbook on this subject  and has performed >3000 athletic movement assessments.  He serves as the National Director of Sports Medicine Innovation for Select Medical, is Chairman of Medical Services for the International Obstacle Racing Federation and associate editor of the International Journal of Athletic Therapy and Training. 

Monday, November 21, 2016

Challenging the Status Quo - A Clinical Commentary Part III

Over the course of the last couple of weeks, we have taken a slightly different direction with our blog, offering more of a clinical commentary than our typical literature review.   20 years of practice with over 15 years in movement assessment has led me to some clear conclusions which we have begun to discuss in detail.  These include:
  1. Movement is very complex and very hard for the majority of people to see and assess
  2. The standard of practice is often 5-10 years behind the literature and clinical advancements
  3. There is a strong correlation to improvements in movement efficiency and to mitigating risk of injury and improving athletic performance
  4. We need to recognize where the flaws are in the current ways we assess movement are so that we can become better at what we do
  5. Sometimes movement is just movement and we try to over complicate it
  6. The standard of practice or care, in my opinion, tends to be the standard of the lazy and status quo. 
Over the last couple of weeks, we discussed in detail #1- #3.  Hopefully this has lead to some reflection on what we do and more importantly what we can do differently.  This week, we will dive into a discussion that I am a little uncomfortable with.  Recognizing where the flaws are in the current ways we assess movement.  I am not uncomfortable because I am unfamiliar with the topic, but uncomfortable with because so many times we get tunnel vision, passionate about we do and hypersensitive if people question it.  People know what they know and get very comfortable with certain assessments.  There is also a lot of passion around what people do and rightly so.  So, this discussion is not about you as a clinician or your thought process but more about the tools which we use.
 
Before we start, let's start with understanding to basic facts.  #1 - Just because something assesses movement does not mean that it is assessing a movement associated with risk.  #2 - Training methods that are designed based on a movement assessment will be affective at making someone stronger no matter what.  If you take someone with a weakness, train that weakness, they will get stronger.  That is not rocket science.  That is why, when seeing results like 30% reduction in injury risk, to me, is nothing to get excited about.  Is that a result we are happy with?  Could we do better?

Keep in mind, the topic of this blog is challenging the status quo.  It is easy to be critical of anything, especially in an environment where the other side is not able to respond to said criticism.  This discussion is not to sway you one way or the other, but is more intended to get people to think outside the box.  Leverage what we know from the literature to constantly question the way we do things.  END OF THE DAY, what we are currently doing is NOT working.  Injury rates continue to rise in youth athletics all the way to professional sports.  We have to do something different.

 
Insanity - doing the same thing over and over and expecting a different result! 
 
As much as we think everyone knows about movement, I am still surprised on a weekly basis how many folks tell me it is the result of turf vs. grass, femoral notch depth, Q-angle, and hormones.  Yes, we know that these are risk factors but can we change those?  And since we can't should we just do nothing?  Absolutely not!  So, I know this has been stated over and over in our blogs, but for refresher, let's look at what movements put you at risk.  Because it is the movements we can measure and the movements we can change.  If changed, this should mitigate injury risk.  Therefore understanding this will help guide our discussion. 
 
Known published risk factors include:
  • Magnitude of knee frontal plane motion – Stearns et al. Am J Sport Med 2014
  • Fatigue increases knee frontal plane motion – Brazen et al. Clin J Sports Med 2010
  • Stability in SL performance best indicator of risk – Myer et al. Am J Sports Med 2012
  • Symmetry in SL performance indicator of risk – Rohman et al. Am J Sports Med 2015
One thing we typically find in our research is that cost, days on the DL and recordable injuries commonly have a substantial percentage of those numbers coming from a few players.  Stated in another way, we find a team of 28 players with high injury costs, recordable injuries and days on the DL that a large percentage of those injuries and costs are coming from 10-15% of the players.  Season over season, they tend to be some of the same players.  So how do we find who those players are?  All too often, we think we need a comprehensive movement assessment to determine risk.  Many times, for efficiency purposes in an athletic setting, we need just one or two movements we can look at that will give us a key indication of risk.  Screen out the worse players.  Those that are found to be at high risk with these movements could then have a more comprehensive assessment. 

So based on the above, can we come up with 2-3 movements which will aid us in identifying risk?  Based on the above, one movement we should look at should be the single leg squat.  But technique and how it is performed is critical.

  • How many Reps should we do?  Due to the impact of fatigue, this should be done for minimum of 10 reps.  This allows us to start to see the impact on performance
  • What should be position of contralateral leg?  Khuu et al In J Sport Phy Ther 2016 showed the difference in EMG activity with SL squat and position of the contralateral limb.  EMG activity with the contralateral leg in extension is very similar to that in sport.  From a specificity standpoint, this position is the one that mimics running position best and the position similar to how the body is positioned during non-contact ACL injuries. 
  • What are motion are we looking for?  During the course of this movement we should be assessing the magnitude of frontal plane motion.  We know that as this motion increases, then so does the risk. 
  • Does speed of motion matter?  In addition to magnitude of motion, we also know that speed at which this motion occurs is a risk factor.  For example valgus at 21 degrees/sec in a single leg squat is a risk and 100 degrees/sec in a single leg hop is a risk.  Although we can't quantify that with our eyeball, we can see if valgus is happening very fast on one side compared to the other. 
  • What about loss of balance?  Loss of balance is a huge risk factor.  The more recordable losses of balance one has during performance of a single leg squat, the more susceptible they are to injury. 
In addition to the above factors, we should also compare right side performance to left.  Rohman et al showed limb symmetry is important.  But, keep in mind, athletes can move equally bad on each leg so we need to also consider all the above.

Although a single leg squat will give us some good idea of movement, another movement that is very telling, is a hop plant test.  In our work, we use both a single leg hop and the single leg hop plant.  However, if I had to choose one over the other, I would choose the single leg hop plant.  It is much harder for an athlete to compensate with this movement. 


During the single leg hop plant, the athlete is asked to stand one leg and hop in a forward direction followed by posterior, then lateral then medial.  They are asked to reframe from touching down the contralateral limb during the course of the test.  It is imperative with this test to do under close supervision and always discontinue the test if you see the athlete is at risk or that the movement is too great. 
  • How many reps?  With this test, we typically do 2 rounds of all 4 directions.  This equates to a total of 8 reps.
  • What do I look for?  You are assessing for all the same factors as above. 
Next week, we will continue this discussion in this area but hopefully this has given us some things to think about and two practical tests we can implement in our screening.  Next week we will continue to discuss some additional movements we can screen in addition to some of the flaws with current movement assessments.

I would like to thank you for being a follower of our blog.  It is an honor that I do not take lightly and from my family to yours, we wish you a joyous and safe Thanksgiving.  I would also like to give a shout out to #TroyTrojans.  One of our #ACLPlayItSafe schools that is nationally ranked for the first time in the universities history! #GoTrojans!
 

Dr. Nessler is a practicing physical therapist with over 17 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment.  He is the developer of an athletic biomechanical analysis, is an author of a college textbook on this subject  and has performed >3000 athletic movement assessments.  He serves as the National Director of Sports Medicine Innovation for Select Medical, is Chairman of Medical Services for the International Obstacle Racing Federation and associate editor of the International Journal of Athletic Therapy and Training. 
 

Monday, November 14, 2016

Challenging the Status Quo - A Clinical Commentary Part II

Last week, we took a slightly different direction with blog, offering more of a clinical commentary than our typical literature review.   I had mentioned that after spending countless years in reviewing of the literature, clinical research and over a decade assessing movement, it led me to some clear conclusions:
  1. Movement is very complex and very hard for the majority of people to see and assess
  2. The standard of practice is often 5-10 years behind the literature and clinical advancements
  3. There is a strong correlation to improvements in movement efficiency and to mitigating risk of injury and improving athletic performance
  4. We need to recognize where the flaws are in the current ways we assess movement are so that we can become better at what we do
  5. Sometimes movement is just movement and we try to over complicate it
  6. The standard of practice or care, in my opinion, tends to be the standard of the lazy and status quo. 
Last week we discussed the complexity of human movement and how difficult it is for most to reliably assess human movement with a high degree of validity.  We further discussed how the standard of practice is typically 5-10 years behind the most current literature and why that may be the case. 

Today we will continue along this route to discuss the implications that poor movement have on athletic performance.  If we take a pure evidence based practice approach, we know that only 43% of athletes who tear their ACL return to the same level of athletic performance (McCullough et al Am J Sport Med 2012).  Whether you are measuring the impact this has on vertical jump, sprint speed or points/rebounds scored (Harris et al Am J Sports Med 2013), we know if you tear your ACL that this has long term impact on athletic performance measures.  But what if you don't tear your ACL.  Do these same movements put you at risk for performance issues. 

Again, if we wanted to take a pure evidence based approach, we could look to the literature to guide us in this respect.  For example, we know that the same movements that put you at risk for a non-contact ACL injury also impact athletic performance (Myers et al J Strength Con Res 2005).  We also know that lack of core stability not only puts you at risk for an ACL injury but also has a direct impact on pitching performance in MLBs (Chaudhari et al Am J Sport Med 2011).  But do we really need a research paper to tell us that? 

Sometimes those of us in the health professions get to caught up on "Is it proven in the literature".  I don't think there is anyone of us, as a coach, strength coach, physical therapist or athletic trainer, that could not look at the athlete in the above picture and know this would impact her athletic performance.  If she is a basketball player, any of us could see this poor movement pattern demonstrated here would have a direct impact on her vertical jump.  If she does this in a bilateral hop, can you imagine what this would look like in single limb performance?  9 times out of 10, if you see this in bilateral performance, you can be guaranteed that you will see this in single limb performance. 

Ok, so I get it.  We may see that in a female high school athlete but if I work at the collegiate or pro level, the kind of movement patterns I see would not be that clear or easy to see.  Really?  Is it that it is not that easy to see, or that when we should be quantifying it we might not be looking at it?  This is a perfect example of a pro athlete who "passed" his movement assessment but when the rubber met the road (broad jump) this is how his mechanics looked.  In high level exceptional athletes, they may perform at extraordinary levels with poor movement.  So do we let that go for fear of messing up their performance?  Does the risk that this puts them at less of an issue in comparison to the "potential" impact on performance?  This is a valid question and one we must consider.  Although there is NO research on this, what we do see is that when these movements are improved, that there is a direct and positive impact on athletic performance.  When the athlete is given a movement specific program that is supplemented with their traditional training, we see that the positive changes in movement are then carried over to their movement during high level athletic performance.  This then equates to improvements in athletic performance. 

Again, this is not validated in the research but I think anyone who deals with athletes, that sees movements like this, see this as truly a no brainer.  Like we said last week, movement is complex.  But what we do see is if you can make an athlete move more efficiently, then you will mitigate their risk for non-contact musculoskeletal injuries and improve their athletic performance. 

Next week, we will continue this discussion and look at challenging the status quo.  I hope what you take away from this section is:

  1. Previous ACL injury has a big impact on future athletic performance - therefore we must do MORE to prevent
  2. Movement has a direct impact on athletic performance!
  3. We need to talk to athletes and coaches more about the impact that our programs have on PERFORMANCE versus injury risk
Taking this approach will improve compliance with programs and create greater adoption of programs by our coaching staff.


Dr. Nessler is a practicing physical therapist with over 17 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment.  He is the developer of an athletic biomechanical analysis, is an author of a college textbook on this subject  and has performed >4000 athletic movement assessments.  He serves as the National Director of Sports Medicine Innovation for Select Medical, is Chairman of Medical Services for the International Obstacle Racing Federation and associate editor of the International Journal of Athletic Therapy and Training. 

Monday, November 7, 2016

Challenging the Status Quo - A Clinical Commentary

Over the course of the last 2 years, I have tried to provide you a weekly blog that is based on the most current peer reviewed literature and evidence.  I am going to veer off that trend for this blog and hope you don't mind.  Please let me explain.  I hope you have enjoyed this blog and the various series within it that we have done.  If you have learned one thing, walked away with one clinical pearl at all during the course of this time, it was all worth it to me.  I am honored to have you as a follower of this blog and appreciate you sharing the passion for injury prevention with me.  This is not a blog that I am paid to do, it takes a lot of time and research but it is something that I take very seriously and am very passionate about.  To me, this was a calling that God called me to.  He called me to be a physical therapist and He called me to take on this challenge.  I don't know why me but I have accepted it and devoted my entire career to it. With His direction and will, we have accomplished some amazing things.  Why do I feel this was a calling?

Back in 1998, in my own practice in Phoenix, Arizona, I had 22 young athletes come into my clinic over a 2 week period of time with ACLR.  During the course of their rehab, I was providing the most current standard of practice to these young athletes.  However, in doing their discharge evaluations and seeing them move, seeing them walk and seeing them run, I could see movement patterns that I knew instinctively that put stress on their ACL and put them at risk for re-injury.  This is prior to all the great literature that we have now so this started me on a mission of discovery.  I felt a deep, deep desire to do something for these kids.  After going back to get my doctorate and spending countless years in reviewing of the literature, clinical research and over a decade in development, it led me to some clear conclusions:

  1. Movement is very complex and very hard for the majority of people to see and assess
  2. The standard of practice is often 5-10 years behind the literature and clinical advancements
  3. There is a strong correlation to improvements in movement efficiency and to mitigating risk of injury and improving athletic performance
  4. We need to recognize where the flaws are in the current ways we assess movement are so that we can become better at what we do
  5. Sometimes movement is just movement and we try to over complicate it
  6. The standard of practice or care, in my opinion, tends to be the standard of the lazy and status quo. 
This is why this is a clinical commentary.  This is based on one person's perception after years of literature review, clinical practice, educating clinicians and assessing 4000+ athletes.  That said, I am Joe Blow PT, I am nobody and have an opinion based on the above.   But it is only my opinion.  Take it or leave it but it will provide insight of why I do what I do and why I do this blog.  This particular blog is a blog to question the status quo.  Whether you are a clinician, a coach and athlete, question what you get from your health care provider.  Sometimes the experts aren't necessarily the experts even though they are very good at convincing you they are.  Laziness bothers me.  Especially if those that the public sees as the leaders are truly taking the easy road out and doing things half ..... (let you fill that in).

Movement is very complex.  Of the 2000+ clinicians (PT, ATC, MDs) that I have taught over the last 15 years, only about 1% can assess movement to the degree that I would consider proficient and accurate.  Is that a training flaw or is it that movement is that complex?  If consider the fact that the medical profession still struggles with development of a comprehensive return to play assessment or even a movement assessment, then I would suggest that it might be that complex.  There is over 15 years of biomechanical literature on movement and yet we STILL don't have it figured out.  Simply stated, when you look at an athlete (like the one pictured here), you have to look at the entire kinetic chain instantaneously.  You have to see what their foot/ankle are doing, the knee, hip and pelvis, and where the core is in relation to the center of gravity.  You have to see where all these same joints and segments are in relation to one another.  You have to see which one falls first in relation to the rest.  And you have to assess all this in an instant.  The human eye and brain are just not equipped to take all that in and interpret it at the speed at which movement occurs.  So, many have resorted to technologies to aid them in assisting in that.

With the advent of some of the 2D technologies, this has done a lot to advance what we know about movement.  It is a great tool and better than the eyeball alone.  Yet, at the same time, many fail to question the true validity and reliability of what they are doing.  Too many believe it is technology and therefore it must be accurate.  All too often, I sit in lectures at professional conferences where a clinician will present a running assessment or movement assessment done with 2D technology where they show improvements in the angle of ankle pronation or knee valgus by 5-10 degrees based on a treatment they did.  So, you are telling me that your treatment improved their movement by 10 degrees?  Or is it that your placement of your starting and ending points of your angular measurements on 2D video was off by 5-10 degrees?  Do they know that studies indicate that there is a 10-15 degree variance in measurements taken from 2D video versus when you measure using palpation and a goniometer or a Viacom system?   Unless they are using markers on the body to palpate the bony landmarks and making measurements from that then you have to question the validity of this measurement.  Do they know that the orientation of the camera to the horizontal and vertical can dramatically change the angular measurement taken from 2D video?   Unless they are using a plumb and level on the camera to ensure this is level to the horizontal and vertical, then you have to question the validity of this measurement.  My point, less than 1% take it to that step and if they aren't then how valid is the information you are getting?  It is fine if you are using that for documenting progress but when you try to apply that to determining an athlete's ability to return to play safely, that is really where we need to proceed with caution.

The standard of practice is often 5-10 years behind the literature.  Case in point.  Recently, I was asked to review an athlete's case that was seeing a local PT.  A PT that is considered to be "the sports medicine guru", treats all the high level athletes and local pros.   This athlete, high level semi pro MMA athlete, chronic knee condition was treated for over a month and being sent for evaluation for return to training camp.  Movement assessment clearly shows where there are some gross deficits and yet review of the chart shows none of those being addressed in a closed kinetic chain training or in the aggressive nature that would an athlete of this nature would need.  Sadly, this athlete even stated where he felt weak and yet this was not even being addressed.  Why is that?  I can't answer that specifically in this case, but what I will say is that had this person been reviewing any of the literature in the last 5-10 years, there would have been a significantly different intervention.  In most cases, most don't review the literature.  Most will rely on what they learn in a course which is sometimes not even most current evidence based.  As a health care professional, it should be our professional obligation to keep up on the literature and use that to develop our evidence based interventions. 

Next week, we will continue this discussion and look at challenging the status quo.  I hope what you take away from this section is:

  1. If you are doing assessments with 2D video, take it to the next level.  Always question the validity of your data.  If you do that, you will ALWAYS look for ways to improve it.
  2. Keep up on the literature.  Don't rely on courses or someone else's interpretation.  Pull the literature, evaluate it and see how this can impact your clinical treatment TODAY!

Dr. Nessler is a practicing physical therapist with over 17 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment.  He is the developer of an athletic biomechanical analysis, is an author of a college textbook on this subject  and has performed >4000 athletic movement assessments.  He serves as the National Director of Sports Medicine Innovation for Select Medical, is Chairman of Medical Services for the International Obstacle Racing Federation and associate editor of the International Journal of Athletic Therapy and Training. 

Monday, October 31, 2016

How Do We Know When Is The Time To Return To Sport? - Part II

In last week’s blog we talked about the impact that injury has on return to sport and specifically the impact on performance.  This led to the question, how do we make return to sport calls.  Is there a way to assess both biomechanical risk factors in a closed kinetic chain and performance measures?  What does the research tell us? There are several ways this is being done today. 

One of the standards of practice is the use of the Functional Movement Screen. But is this a good predicative tool for determining return to play?   

  • Bardenett et al - Int J Sports Phy Ther 2015 - looked at the FMS as a predictive tool in high school athletes.  Of the 167 high school athletes that were assessed during the pre-season, the results showed the FMS was good at recognizing asymmetry in the movements tested.  But they found that the results were not a good at predicting injury.
  • Dorrel et al - J Ath Train 2015 - performed a systematic review and meta-analysis of research from 1998 to 2014.  What the results showed was that the FMS demonstrated low predictive validity for injury prediction and leading the authors to conclude that this should not be used for injury prediction.
  • Bushman et al Am J Sports Med 2016 - looked at the FMS as a predictive tool in active male soldiers.  Of the 2476 soldiers assessed, the FMS demonstrated low sensitivity and low positive predictive value.  This lead the authors to conclude this could lead to misclassification of injury risk in military personnel.  If they are assigned to hazardous duty as a result of this misclassification, it could potentially place the soldier at greater risk.
  • Wright et al Bri J Sports Med 2016 - in this clinical commentary based on the literature review showing a low sensitivity of 24% led the authors of this paper recommending that this should not be used for injury prediction or for making return to sport calls.
On clear example of this is a recent paper, Dobson et al, Ortho J Sports Med 2016, that looked at injury rates, specifically ACL injuries in NFL players.  Despite implementation of the FMS, biodex testing of quad to hamstring ratios and other such tests, NFL ACL injury have risen dramatically.  Up till 2010, ACL injury rates were occurring at a rate of ~10 ACL injuries per year.  From 2010-2016 there have been a recorded 219 ACL injuries (~36/yr).  So despite having access to all the latest information, they are still not impacting them in a positive way.  What gives?  Simply stated, we are NOT looking at the right things.  When a player can score a 17 on a screen and yet his knees nearly touch on a broad jump, then we are obviously not looking in the right direction.

In 2011 Grindem et al published a paper looking at the single leg hop tests as a predictor of knee function.  In this study the authors compared the single leg hop test to the International Knee Documentation Committee (IKDC).  The IKDC is a self-reported outcome measure that has been shown to have a very sensitivity and specificity to actual knee function.  The authors compared the results on the single leg hop to IKDC scores for those who had ACLR.  The following diagram indicates the single leg hop tests that were performed.  This study showed that symmetry in single leg hop for distance predicted self-reported knee function on the IKDC with a high degree of sensitivity and specificity.   The single leg hop for distance is a great measure of power output in the horizontal.  This same measure of power output can also be obtained with a single leg for height.  One is great for forward propulsion (hop for distance) and one is great for vertical propulsion (hop for height).  Both of these are critical in sport but when also considering mechanics (adduction in the frontal plane) how do you quantify that with either of these tests?  Or is that even possible? With the advent of technology, it is possible, at least for the vertical single leg hop.  Taking a look at the picture here, we can easily capture not only quantify the mechanics with the single leg hop but we can also quantify her vertical displacement during the test.  Having both of these factors performed over multiple repetitions, we can then get a biomechanical assessment of risk as well as comparison of the right limb to the left limb in terms of power output.   But how do we do that objectively and with a high degree of reliability?
As we have stated in previous blogs, frontal plane motion is not the only risk factor.  Rohman et al Am J Sport Med 2015 showed that symmetry in single limb performance is a critical measure for risk.  We also know from Kristinaslund et al Am J Sports Med 2013 that one of the best indicators of risk and athletic performance is performance in single limb testing.  We can watch and record these movements with various technologies (like Dartfish) but that is often time consuming and takes a higher level or expertise to be able to do it in a fashion that is efficient and reliable.  In addition to 2D technology, we are seeing a plethora of new 3D wearable sensor technologies hit the market that are extremely reliable.  Many of these use IMU (inertial measurement units) with accelerometers, gyrometers and magnetometers to detect motion, rotation and acceleration data.  With these technologies, we can now quantify movement with lab quality results and are able to quantify both the magnitude of valgus that occurs in addition to the speed at which that motion occurs. 

As we see a further blending of these types of technologies with the movement sciences is when we will really see an impact on both lower limb injury rates and improvements in athletic performance.


Dr. Nessler is a practicing physical therapist with over 17 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment.  He is the developer of an athletic biomechanical analysis, is an author of a college textbook on this subject  and has performed >3000 athletic movement assessments.  He serves as the National Director of Sports Medicine Innovation for Select Medical, is Chairman of Medical Services for the International Obstacle Racing Federation and associate editor of the International Journal of Athletic Therapy and Training. 
 

Monday, October 24, 2016

How Do We Know When Is Time To Return To Sport? - Part I

Over the course of the last several years, we have posed the question, “Does Return to Sport = Return to Sport Same Level?”  This is a topic that is still not quite clear in the research and one which is becoming clearer and hotly debated.  As , what is reported in the literature depends on how you quantify return to sport.  Is this simply returning to play or is it returning to play with pre-injury level of agility, speed, power?  How do you determine pre-injury level of agility, speed and power?  This will vary greatly by sport.  However, we are starting to see researchers look more closely performance measures when looking at "return to play".  Some of the current measures being assessed include:
 
  • Timed 10 yard split or 40 yard dash
  • Vertical jump or single leg hop for distance
  • Timed agility drills
  • Time to take down (MMA)
Depending on how you quantify your return to play criteria will often lead to varied interpretation of the results.  In research, performance measures have not been typically evaluated and as such, reporting return to play percentages have been a lot higher than what we see on the field.  In a recent study by Anand et al, Am J Sports Med 2016, we see when we start to look at some of the performance criteria, that the percentages are much lower than previously reported.  
 
So how do we currently make the call to return an athlete to sport?  Who decides when it is time to return to sport and how do we know if the athlete is ready?  Currently there is not a standardized way to make return to sport calls.  Wilk et al, J Sport Phys Ther 2014, in an editorial and literature review, asked that very question.  Can we do better?
This is something that is desperately needed and being asked for.  More often than not, making this call relies heavily on the surgeon to aid in making that decision.  Often the surgeon will base this decision on what the current research says about tissue healing and graft strength, an extensive orthopedic exam performed in his office, comparison of involved limb to non-involved limb strength on Biodex testing and often feedback from the treating physical therapist or athletic trainer.  Currently, this decision is based on the most current and up to date information we have available.  Or is it?  Does an open kinetic chain strength test (Biodex) really tell us anything about how stable the limb is in closed kinetic chain conditions, in running, landing or cutting situations?  Adduction in the frontal plane is a risk factor and hip strength plays a big role in.  Does this test give an indication of hip strength?  Is there a better way to assess frontal plane motion?
The reason all this is so important is due to the number of athletes that return to play too early and end up being re-injured.  We know from Rugg et al, Am J Sports Med 2014 that players with a previous ACL injury are at an 8 fold increased risk of re-injury, will consume more time on the DL and cost more in health care dollars.  Return too early and you increase injury risk.  Return too early and performance is negatively impacted.  We can all think of a NFL or NBA player who has had an ACLR and once they returned to play, just did not play at the same level as previous or hesitated to move to the injured side.  We can all think of a UFC fighter that was hesitant to move to the previously injured side upon return to the ring.  That hesitation, that lack of confidence has a huge performance impact.

Over the last couple of years, several papers have attempted to look at just that.  In some of our previous blogs we cited   McCullough et al who published a MOON study in 2012 that looked at return to sport following ACL reconstruction.  What they showed was that 63% of high school players and 69% of college players were able to return to sport following ACL reconstruction.  They also showed that only 43% of those athletes were able to return to the same level of sport as prior.  In this case, return to same level of sport was defined as same level of pre-injury performance as self-reported by the athlete.  Similar studies have attempted to do this in NBA players.  Harris et al published a paper in 2013 that looked at the impact of ACLR on future performance in fifty-eight NBA players.  Performance was measured by comparing pre-injury data to post injury data in the following areas: games per season played, minutes played, points & rebounds per game and field goal percentage.  Several interesting findings came out of this study including 40% of the players who tore their ACL during a game, did so in the fourth quarter.  86% of players returned to the NBA and 12% of players returned to the FIBA or D-league.  98% of the players that returned to the NBA and 3% had revision of their ACL.  Performance upon return to sport following surgery declined significantly for all subjects.  However, this was not statistically significant when compared to controls during this same time period.  Busfield et al 2009 also investigated this in NBA players.  They looked at 27 NBA players who had ACLRs.  Of those, 22% did not return to the NBA and 78% did return to play.  Of the 78%, 15% had an increase from pre-injury performance and 44% had a significant reduction from pre-injury performance.
In both of these studies, return to play was determined by performance measures in the game (points, rebounds, free throws, etc).  All of these are good measures of performance but are indirect measures of power output, sprint speed and agility.  Is there a more direct way to measure this impact?  In a June 2014 paper for the American Journal of SportsMedicine, Aune et al looked at return to play in NFL players after a lateral meniscectomy.  In this study, return to play was defined as the ability to play in a regular season game.  Of the 77 subjects, 61% were able to return to play.  Additional findings included only 24.6% of the 77 subjects where still playing in the NFL at follow up (average 4.5 years) and speed position players (running backs, linebackers, etc) were 4.0 times less likely to return to play. 
All these studies bring out some key facts. 

  • Performance is negatively impacted by injuries and with return to sport.  This highlights the importance of directly measuring the pre/post performance variance. 
  • The fact that over 40% tore their ACL in the fourth quarter tells us that fatigue plays a significant role.  This highlights the importance of considering this in the assessment with return to play.    
  • The fact that speed position players were 4.0 times less likely to return to play may indicate the impact that injury has on power output.  Since these positions are so dependent on explosive power and agility, you would expect that if injury does have a big impact on performance that these positions would be the most significantly impacted.
The research is clearly telling us that injury does have an impact on performance.  As such, should we include this as a part of our assessment in return to sport and if we do, how do we do it?  Some will tell you the answer is clear and they are currently doing.  But do we have a standardized return to sport protocol?  No!  Whether it is an agility test, single leg hop test or figure eight, these tests are still very subjective and athletes will often figure out how to compensate to obtain desirable results.  Is there a way to assess an athlete for return to sport that also assesses biomechanical symmetry and performance symmetry?  Yes!  Make sure to check out part II next week we will discuss that in more detail.



Dr. Nessler is a practicing physical therapist with over 17 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment.  He is the developer of an athletic biomechanical analysis, is an author of a college textbook on this subject  and has performed >3000 athletic movement assessments.  He serves as the National Director of Sports Medicine Innovation for Select Medical, is Chairman of Medical Services for the International Obstacle Racing Federation and associate editor of the International Journal of Athletic Therapy and Training.