Podcast 88: interpreting Shoe Wear patterns & Running Surface Effects

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Plus: Biometrics in Pro Sports, Epigenetics and How Exercise changes our DNA, Hip Dysplasia„ Pavlik harnesses.

We hope you find today’s show helpful. Remember, we don‘t know everything, and we do not expect everyone else to know everything either. We are just bringing our logic and knowledge and hopefully truth to the web … . . Please, Correct us when we are sharing inaccuracies, as we try to do the same. There is alot of misguided info on the web and in the wrong hands, people can get hurt … . we feel we are doing our part to carve a safe path. But, when we go astray, please our dear brethren……call us out on it ! We insist. -Shawn and Ivo

Other Gait Guys stuff

Download links:

A. http://traffic.libsyn.com/thegaitguys/pod_88_solid.mp3

B. http://thegaitguys.libsyn.com/podcast-88

iTunes link:

Gait Guys online /download store (National Shoe Fit Certification and more !) :

other web based Gait Guys lectures:
Monthly lectures at : www.onlinece.com   type in Dr. Waerlop or Dr. Allen,  ”Biomechanics”

Show notes:

New biometric tests invade the NBA

How Exercise Changes Our DNA

An integrative analysis reveals coordinated reprogramming of the epigenome and the transcriptome in human skeletal muscle after training. Lindholm ME
Epigenetics. 2014 Dec 7:0. [Epub ahead of print]

Hip Dysplasia

Journal of Pediatric Orthopaedics:
January 2015 – Volume 35 – Issue 1 – p 57-61
Back-carrying Infants to Prevent Developmental Hip Dysplasia and its Sequelae: Is a New Public Health Initiative Needed? Graham, Simon M.

Plus: Pavlik harness

Does Correct Head Positioning Make You Run Faster?http://runnersconnect.net/running-injury-prevention/running-form-proper-head-position/

Running surfaces

How to Read and Interpret the Wear Pattern on Your Running Shoes

Do you know your stuff? Would you correct this child’s gait ? Give them orthotics, exercises, force correction, leave them alone ? 

Is he Internal Tibial torsioned ? Is he “pigeon toed” ,if that is the only lingo one knows, 😦  Does he have femoral torsion ?  A pronation problem locally at the foot or an internal spin problem through the entire limb ? Or a combination of the above ? 

What’s your solution?

It MUST be based on the knowledge necessary to fix it, not the limits of YOUR knowledge. You can never know what to do for this lad from his gait evaluation, no matter how expensive your digital, multi-sensor, 3D multi-angle, heat sensor, joint angle measuring, beer can opening, gait analysis set up is. You can never know what to do for this lad if you do not know normal gait, normal neuro-developmental windows, normal biomechanics, know about torsions (femoral, tibial, talar etc), foot types etc.  It is a long list.  You cannot know what to do for this kid if you do not know how to accurately and logically examine them. 

Rule number 1. First do no harm.

If your knowledge base is not broad enough, then rule number one can be easily broken ! Hell, if you do not know all of the parameters to check off and evaluate, you might not even know you are breaking rule number one !  If everything looks like a weak muscle, every solution will be to “activate” and strengthen and not look to find the source of that weakness.  Muscles do not “shut down” or become inhibited because it is 10 minutes before practice or because it is the 3rd Monday of the month. You are doing your client a huge disservice if you think  you are smarter than their brain and activate muscles that their brain has inhibited for a reason. What if it were to prevent joint loading because of a deeper problem ?  If every foot looks flat and hyper pronated, and all you know is orthotics or surgery or shoe fit, guess what that client is prescribed ? If all you see is torsions, that is all you will look to treat. If all you see is sloppy “running form” and all you know is “proper running form” forcing your client into that “round peg-square hole” can also lead to injury and stacking of compensation patterns.  

One’s lack of awareness and knowledge, are one’s greatest enemies. If you don’t know something exists, because you’ve never studied or learned it, how can you be aware of it ? If you’re not spending enough time examining a client, you might not be aware of an issue even though you may be knowledgeable about the issue.
One must have both awareness and knowledge. One must also be aware that compensations are the way of the body. What you see is not your client’s problem. It is their strategy to cope.

Are you helping your client ? Hurting them ?  Adding risk to their activity ? Are you stepping beyond your skill set ?  

Rule Number 1: First do no harm. 

Shawn and Ivo

PS: we will get to this case another time, we just wanted to make a point today about the bigger problems out in the world.

the gait guys

Podcast 87: Podcast 87: The Kenyan’s Running Brain & “The” Anterior Compartment.

Plus, Some unknown facts about going minimalism and barefoot. We POUND anterior compartment strength today gang ! Hope you enjoy !

Show sponsors:

A. Link to our server: 

Direct Download: 

Other Gait Guys stuff

B. iTunes link:

C. Gait Guys online /download store (National Shoe Fit Certification and more !) :

D. other web based Gait Guys lectures:
Monthly lectures at : www.onlinece.com   type in Dr. Waerlop or Dr. Allen,  ”Biomechanics”

Show notes:

On high heels and short muscles: A multiscale model for sarcomere loss in the gastrocnemius muscle


The Brain Needs Oxygen

Maintained cerebral oxygenation during maximal self-paced exercise in elite Kenyan runners.

J Appl Physiol (1985). 2014 Nov 20:jap.00909.2014. doi: 10.1152/japplphysiol.00909.2014. [Epub ahead of print]

The texting lane in China

Dialogue on endurance training,
NeuroRehabilitation. 2006;21(1):43-50. 

Effects of dorsiflexor endurance exercises on foot drop secondary to multiple sclerosis.  Mount J1, Dacko S.

APOS Therapy
we were asked out opinion on this

Foot instrinsic dialogue
Motor Control. 2014 Jul 15. [Epub ahead of print]

Quantifying the Contributions of a Flexor Digitorum Brevis Muscle on Postural Stability.
Okai LA1, Kohn AF.

There are many factors in adults that impair gait. It is not all biomechanical. This is part of our ongoing dialogue on the aging population and why gait impairments and falls are so prevalent.
Acta Bioeng Biomech. 2014;16(1):3-9.
Differences in gait pattern between the elderly and the young during level walking under low illumination.
Choi JS, Kang DW, Shin YH, Tack GR.

Podcast 86: The Best of The Gait Guys Podcast: Part 1

Show sponsors:


A. Link to our server: 


Direct Download: 


Other Gait Guys stuff

B. iTunes link:


C. Gait Guys online /download store (National Shoe Fit Certification and more !) :


D. other web based Gait Guys lectures:

Monthly lectures at : www.onlinece.com   type in Dr. Waerlop or Dr. Allen,  ”Biomechanics”

Test your Mental Clinical Thinking Skills with this pedograph case. 

A few months ago, we discussed this case in great detail. There is likely little chance you will see our thinking progression with these final conclusions without sitting down with a warm cup of coffee and going over these 2 prior blog posts on this case (part 1 and part 2).  Besides, it will be a good review for you and it is great mental gymnastics.  This kind of analysis gets easier each time you do it but we have to through out our standard warning. This is the kind of stuff one needs to be able to go through on the fly in one’s practice, it is something to aspire to.

First of all, caveats:

  • Our discussions on this case were all theoretical.  What we went through was an exercise in static assessment and clinical thinking
  • One cannot, and must not, make clinical decisions from a static assessment. 
  • As in all assessments, information is taken in, digested and then MUST be confirmed, denied and/or at the very least, folded into a functional and clinically relevant assessment of the client before the findings are accepted, dismissed and acted upon. 
  • Gait analysis or pedograph-type assessment are helpful tools, but not the final answer.

Our static exam proposal on this case came up with the following theories (please stand up and mimic as we discuss, trust us, it will help you). *Remember: the foot on YOUR LEFT is the RIGHT foot for the purposes of this discussion. And remember, this is all theoretical, this is an exercise in biomechanical and clinical thinking, nothing more.

  • Suspect Counter-clockwise pelvis distortion pattern (causes relative internal rotation on LEFT and external rotation on RIGHT), this will drive Left knee hyperextension and Right knee flexion (hence foot plantar pressures as we discussed in previous 2 blog posts linked above). This of course cannot be seen, but we are extrapolating from our clinical experiences.
  • poor pronation and internal limb spin control on the left (hence longer foot and toe hammering). Obviously, we would see a dramatic shift of the pressures to the medial foot if this were truly the case.  Perhaps this is because of the greater lateral left pelvis drift forcing the glute and foot pronatory controls to have to work harder and longer, and maybe even quicker, to control the internal spin and pronation. Over time, they fatigue and fail rendering a flatter, more pronated and longer heel:toe ball length ratio. This would also give credence to the left toe hammering/gripping response.
  • static increased left limb weight bearing (left hip drift)
  • abrupt right foot loading pattern (more mid-forefoot strike), perhaps as reflected by the static forefoot loading. Again, supposition.
  • with all of the above, it is suspect that this client will appear to have a subtle limp, coming off the left quickly or prematurely as they speed through uncontrolled pronation and resulting in an abrupt right limb loading response that mostly skips through heel strike and results in a more aggressive mid-forefoot loading response.  This, sort of, creates a catching of the loading response by the quadriceps more than the gluteals. This can cause medial knee drift (valgus loading) if the medial knee stabilizers are not up to task, this also creates a sudden patellofemoral compresson event and unappreciated sudden tension on the extensor mechanism (the quad-patella-patellar tendon complex).  Can you say generic anterior knee pain ?

Just some thoughts. Please go back to the prior 2 blog posts to delve deeper into the conclusions we have brought about here, we have other good reasoning to suspect the above as the scenario. But remember, what you see is not the problem, we see people’s compensations, their strategies. This was just an exercise in “what ifs”, nothing more. But you will see it in your clinic, just substantiate it with an exam, not what you necessarily see in your clients gait or static assessment. Static assessments are for fools, don’t be a fooled fool.  What  you see is not the problem.

Remember this critical fact.  After an injury or a long standing problem, the job of muscles and motor patterns is to stabilize and manage loads (stability and mobility) for adequate and necessary movement. Injuries often leave a mark on the system as a whole because adaptation was necessary during the initial healing phase. This usually spills over during the early movement re-introduction phase, particularly if movement is reintroduced too early or too aggressively.  Plasticity is often a culprit. Just because the injury has come and gone does not mean that new patterns of skill, endurance, strength (S.E.S -our favorite mnemonic), stability and mobility were not subsequently built onto the apparently trivial remnants of the injury. There is nothing trivial if it is abnormal. The forces must, and will, play out somewhere in the body and this is often where pain or injury occurs but it is rarely where the underlying problem lives. Is the compensation top down, bottom up, or both ?

Don;t be a fooled fool. Get the facts.

Shawn and Ivo, the gait guys

The case of the dropped (plantarflexed) metatarsal head. Or, “How metatarsalgia can happen”.

This gentleman came in with fore foot pain (3rd metatarsal head specifically), worse in the AM upon awakening, with first weight bearing that would improve somewhat during the day, but would again get worse at the end of the day and with increased activity. The began insidiously a few months ago (like so many problems do) and is getting progressively worse.

Rest and ice offer mild respite, as does ibuprofen. You can see his foot above. please note the “dropped” 3rd metatarsal head (or as we prefer to more accurately say, “plantarflexed 3rd metatarsal head”) and puffiness and prominence in that area on the plantar surface of the foot. 

To fully appreciate what is going on, we need to look at the anatomy of the short flexors of the foot. 

The flexor digitorum brevis (FDB) is innervated by the medial plantar nerve and arises from the medial aspect of the calcaneal tuberosity, the plantar aponeurosis (ie: plantar fascia) and the areas bewteen the plantar muscles. It travels distally, splitting at the metatarsal phalangeal articulation (this allows the long flexors to travel forward and insert on the distal phalanges); the ends come together to divide yet another time (see detail in picture above, yes, we are aware it is the hand, but the tendon structure in the foot is remarkably similar)) and each of the 2 portions of that tendon insert onto the middle of the middle phalanyx (1) 

As a result, in conjunction with the lumbricals, the FDB is a flexor of the metatarsal phalangeal joint, and proximal interphalangeal joint (although this second action is difficult to isolate. try it and you will see what we mean). In addition, it moves the axis of rotation of the metatasal phalangeal joint dorsally, to counter act the function of the long flexors, which, when tight or overactive, have a tendency to drive this articulation anteriorly (much like the function of the extensor hallucis brevis above in the drawing from Dr Michauds book, yes, we are aware this is a picture of the 1st MTP).

Can you see the subtle extension of the metatarsal phalangeal joint and flexion of the proximal interphalangeal joint in the picture?

We know that the FDB contracts faster than the other intrinsic muscles (2), playing a tole in postural stability (3) and that the flexors temporally should contract earlier than the extensors (4), assumedly to move this joint axis posteriorly and allow proper joint centration. When this DOES NOT occur, especially if there is a concomitant loss of ankle rocker, the metatarsal heads are driven into the ground (plantarflexion), causing irritation and pain. Metatarsalgia is born….

So what is the fix? Getting the FDB back on line for one. 

  • How about the toe waving exercise? 
  • How about the lift spread reach exercise? 
  • How about retraining ankle rocker and improving hip extension?
  • How about an orthotic with a metatarsal pad in the short term? 
  • How about some inflammation reducing modalities, like ice and pulsed ultrasound. Maybe some herbal or enzymatic anti inflammatories?

The Gait Guys. Increasing your gait and foot literacy with each and every post. 

1. http://en.wikipedia.org/wiki/Flexor_digitorum_brevis_muscle

2. Tosovic D1, Ghebremedhin E, Glen C, Gorelick M, Mark Brown J.The architecture and contraction time of intrinsic foot muscles.J Electromyogr Kinesiol. 2012 Dec;22(6):930-8. doi: 10.1016/j.jelekin.2012.05.002. Epub 2012 Jun 27.

3.Okai LA1, Kohn AF. Quantifying the Contributions of a Flexor Digitorum Brevis Muscle on Postural Stability.Motor Control. 2014 Jul 15. [Epub ahead of print]

4. Zelik KE1, La Scaleia V, Ivanenko YP, Lacquaniti F.Coordination of intrinsic and extrinsic foot muscles during walking.Eur J Appl Physiol. 2014 Nov 25. [Epub ahead of print]

Learning and being humbled.

There is a quote out there by someone that suggests that in the moments of talking and teaching one will learn nothing, for one is merely spouting off the limits of what one already knows, some of which is likely outdated or incorrect. One cannot teach that which one has not previously heard, experienced and mastered.
*Learning is about listening, and evaluating our prior beliefs against the current wisdom. It is about unlearning the false and relearning the latest truths that have come to light. Learning is not about talking.

Dear Gait brethren: Ivo and I do not have all the answers, but we seek and share what we know daily in this realm of The Gait Guys. Through challenging old and current theories, principles and research, one’s insight and wisdom can only grow. We will get things wrong, and we will admit when we do, and thank those who teach us the present truths. We have no single guru we follow, nor should you. No one person or method has all the answers to all of your client’s woes. The day you only trust one guru and one theory and the day you stop seeking, learning, unlearning, and being humbled to the mistakes one has made and been taught, is the day one begins a journey to being left behind and possibly insignificant in time. Thanks to all of you who correct us, teach us, humble us and trust us. It has been a great year here on TGG, thanks for hanging out with us ! 
“The illiterate of the 21st century will not be those who cannot read and write, but those who cannot learn, unlearn, and relearn.” ~Alvin Toffler.
Enjoy the funny cartoon, it is sort of related to the words above. It is a huge comment on communication, communication in relationships and possibly stuff that gets communicated in seminars. Things get lost in translation everyday, sadly. But perhaps that is a good thing, perhaps that is why theories and principles morph into greater wisdom. Not all change is bad.