More foot exercise studies to confuse you.

Don't necessarily believe all that you read. Please to not take away from this study that these 4 exercises: short-foot exercise, toes spread out, first-toe extension, second- to fifth-toes extension are golden goose exercises to rehab your athlete. On first glance if one is not thinking, that could be a mistake in translation.

"The intrinsic foot muscles maintain the medial longitudinal arch and aid in force distribution and postural control during gait."  That is a pretty bold statement by the study's authors. We would argue that a far less misleading statement would be that "the intrinsic foot muscles are a piece of the puzzle, just a piece, and to dismiss the powerhouse tibialis anterior, tibialis posterior, long and short toe flexors and particularly the extensors is a glaring oversight".  Yes, I know, the authors just wanted to study the intrinsics, I get it, -- one just has to be careful of the conclusions made when the study is so microscopic compared to the global perspective at hand.  Please, read on.

This study tried to correlate the effects of these 4 exercises: short-foot exercise, toes spread out, first-toe extension, second- to fifth-toes extension on activation of the foot intrinsics muscles they chose to observe (abductor hallucis, flexor digitorum brevis, abductor digiti minimi, quadratus plantae, flexor digiti minimi, adductor hallucis oblique, flexor hallucis brevis, the interossei, and lumbricals).

They looked at the activation before and after exercise in just 8 athletes. They did not look at non-athletes and yes, this is a terribly small N sampling and the study only used T2 weighted MRI to make these conclusions.

The study's conclusion was "Each of the 4 exercises was associated with increased activation in all of the plantar intrinsic foot muscles evaluated.".  

Here is my concern*. 
Did they consider the various foot typings ? (*Caveat, I have not read the entire study, I am trying to get it). There are many variables to consider including arch integrity, forefoot type, rearfoot type, foot flexibility, step width, step length, client weight amongst other things. Yes, that makes for a near impossible study, I get it. And, it does not appear they had a control study that looked at what happened right after walking. Wouldn't it be fair, and wise,  to see what the study showed after barefoot walking for 1-2 minutes ? I bet many of these muscles show significant activation there as well, after all, they were weight bearing and stepping down on the foot which requires the muscles to be activated and utilized.  So, does that then mean these 4 exercises are any better than walking ? Does that mean they will suffice for homework for your client ? Does that mean they will strengthen these muscles ? And, does activation mean proper pattern utilization of these muscles, meaning, is there functional translation over to functional use ? Yes, that is not what the study was looking at, but for darn sure that would have been nice info to know. Just take the study for what it found, and do not step beyond those tiny boundaries. We hope that is what they will go for in the next stage of study.  To be fair, they also concluded, "These results MAY have clinical implications for the prescription of specific exercises to target individual intrinsic foot muscles."  Safe words. Yes, I capitalized the word MAY.

- Dr. Shawn Allen, one of the gait guys.

Thomas M. Gooding, Mark A. Feger, Joseph M. Hart, and Jay Hertel (2016) Intrinsic Foot Muscle Activation During Specific Exercises: A T2 Time Magnetic Resonance Imaging Study. Journal of Athletic Training In-Press. 
http://natajournals.com/doi/abs/10.4085/1062-6050-51.10.07
http://dx.doi.org/10.4085/1062-6050-51.10.07

Development of the arch: Functional implications | Lower Extremity Review Magazine

A nice, referenced piece from one of our fav’s, Dr Michaud.

“Although early research suggested a limited connection between arch height and lower extremity function, more recent research confirms that arch height does indeed affect function. Information obtained from measurements that accurately identify the height of the medial longitudinal arch may lead to more effective treatment protocols. By identifying specific injuries associated with low and high arches, it may also be possible to prevent these injuries.”

Attempting to regain a level playing ground for your foot.

“Remember, we were born with both our rearfoot and forefoot designed to engage on the same plane (the flat ground). We were not born with the heel raised higher than the forefoot. And, the foot’s many anatomically congruent joint surfaces, their associated ligaments, the lines of tendon pull and all the large and small joint movements and orchestrations with each other are all predicated on this principle of a rearfoot and forefoot on the same plane. This is how our feet were designed from the start.  This is why I like shoes closer to zero drop, when possible, because I know that we are getting closer to enabling the anatomy as it was designed. This is not always possible, feasible, logical or reasonable depending on the problematic clinical presentation and there is plenty of research to challenge this thinking, yet plenty to support is as well. The question is, can you get back to this point after years of footwear compensating ? Or have your feet just changed too much, new acquired bony and joint changes that have too many miles on the new changes ? Perhaps you have spent your first 20-50 years in shoes with heeled shoes of varying heel-ball offset. Maybe you can get back to flat ground, maybe you cannot, but if you can, how long will it take? Months ? Years ?  It all makes sense to me, but does it make sense for your feet and your body biomechanics after all these years ? Time will tell.” -Dr. Allen

Fundamental foot skills everyone should have, subconsciously. This video shows a skill you must own for good foot mechanics. It needs to be present in standing, walking, squatting, jumping and the like. It is the normal baseline infrastructure that you must have every step, every moment of every day. 

Is your foot arch weak ? Still stuffing orthotics and stability shoes up under that falling infrastructure ? Try rebuilding a simple skill first, one that uses the intrinsic anatomy to  help pull the arch up.  If your foot is still flexible, you can likely re-earn much of the lost skills, such as this one. This is a fundamental first piece of our foot, lower limb and gait restoration program. We start here to be sure this skill is present, then add endurance work on it and then eventually strength and gait progressions. This is where it starts for us gang. 

Shawn and Ivo, the gait guys

Podcast 69: Advanced Arm Swing Concepts, Compensation Patterns and more

Plus: Foot Arch Pathomechanics, Knee Pivot Shift and Sesamoiditis and more !

A. Link to our server: 

http://traffic.libsyn.com/thegaitguys/pod_70ff.mp3

Direct Download: http://thegaitguys.libsyn.com/podcast-70

Permalink: 

B. iTunes link:

https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138

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

http://store.payloadz.com/results/results.aspx?m=80204

D. other web based Gait Guys lectures:

www.onlinece.com   type in Dr. Waerlop or Dr. Allen,  ”Biomechanics”

______________

Today’s Show notes:

1. “Compensation depends on the interplay of multiple factors: The availability of a compensatory response, the cost of compensation, and the stability of the system being perturbed.”
What happens when we change the length of one leg? How do we compensate? Here is a look at the short term consequences of a newly acquired leg length difference.
http://www.ncbi.nlm.nih.gov/pubmed/24857934
2. Medial Longitudinal Arch Mechanics Before and After a 45 Minute Run
http://www.japmaonline.org/doi/abs/10.7547/12-106.1

3. Several months ago we talked about the pivot-shift phenomenon. It is frequently missed clinically because it can be a tricky hands on assessment of the knee joint. In this article “ACL-deficient patients adopted the … .* Remember: what you see in their gait is not their problem, it is their strategy around their problem.
http://www.clinbiomech.com/article/S0268-0033(10)00264-0/abstract

4.Do you know the difference between a forefoot supinatus and a forefoot varus?
"A forefoot varus differs from forefoot supinatus in that a forefoot varus is a congenital osseous deformity that induces subtalar joint pronation, whereas forefoot supinatus is acquired and develops because of subtalar joint pronation. ”
http://www.ncbi.nlm.nih.gov/pubmed/24980930

5. Pubmed abstract link: http://www.ncbi.nlm.nih.gov/pubmed/24865637
Gait Posture. 2014 Jun;40(2):321-6. Epub 2014 May 6.
Arm swing in human walking: What is their drive?
Goudriaan M, Jonkers I, van Dieen JH, Bruijn SM

6. This is Your Brain On Guitar
http://www.the-open-mind.com/this-is-your-brain-on-guitar/


Why alignment of the big toe is so critical to gait, posture, stabilization motor patterns and running.

There are two ways of thinking about the arch of the foot when it comes to competent height.  One perspective is to passively jack up the arch with a device such as an orthotic, a choice that we propose should always be your last option, or better yet to access the extrinsic and intrinsic muscles of the foot (as shown in this video) to compress the legs of the foot tripod and lift the arch dynamically.  Here today we DO NOT discuss the absolute critical second strategy of lifting the arch via the extensors as you have seen in our “tripod exercise video” (link here) but we assure you that regaining extensor skill is an absolute critical skill for normal arch integrity and function.  We like to say that there are two scenarios going on to regain a normal competent arch (and that does not necessarily mean a high arch, a low arch can also be competent….. it is about function and less about form): one scenario is to hydraulically lift the arch from below and the other scenario is to utilize a crane-like effect to lift the arch from above. When you combine the two, you restore the arch function.  In those with a flat flexible incompetent foot you can often regain normal alignment and function.  But remember, you have to get to the client before the deforming forces are significant enough and have been present long enough that the normal anatomical alignments are no longer possible. For example, a hallux valgus with a large bunion (this person will never get to the abductor hallucis sufficiently) or a progressively collapsed arch that is progressively becoming rigid or semi-rigid.

Think about these concepts today as you watch your clients walk, run or exercise.  And then consider this study below on the critical importance of the abductor hallucis muscle after watching our old video of Dr. Allen’s competent foot.  

CONCLUSIONS AND CLINICAL RELEVANCE:

The abductor hallucis muscle acts as a dynamic elevator of the arch. This muscle is often overlooked, poorly understood, and most certainly rarely addressed. Understanding this muscle and its mechanics may change the way we understand and treat pes planus, posterior tibial tendon dysfunction, hallux valgus, and many other issues that lead to a challenge of the arch, effective and efficient gait. Furthermore, its dysfunction and lead to many aberrant movement and stabilization strategies more proximally into the kinetic chains.

*From the article referenced below,  “Most studies of degenerative flatfoot have focused on the posterior tibial muscle, an extrinsic muscle of the foot. However, there is evidence that the intrinsic muscles, in particular the abductor hallucis (ABH), are active during late stance and toe-off phases of gait.“

We hope that this article, and the video above, will bring your focus back to the foot and to gait for when the foot and gait are aberrant most proximal dynamic stabilization patterns of the body are merely strategic compensations.

Study RESULTS:

All eight specimens showed an origin from the posteromedial calcaneus and an insertion at the tibial sesamoid. All specimens also demonstrated a fascial sling in the hindfoot, lifting the abductor hallucis muscle to give it an inverted ‘V’ shaped configuration. Simulated contraction of the abductor hallucis muscle caused flexion and supination of the first metatarsal, inversion of the calcaneus, and external rotation of the tibia, consistent with elevation of the arch.

http://www.ncbi.nlm.nih.gov/pubmed/17559771

Foot Ankle Int. 2007 May;28(5):617-20.

Influence of the abductor hallucis muscle on the medial arch of the foot: a kinematic and anatomical cadaver study.

Wong YS. Island Sports Medicine & Surgery, Island Orthopaedic Group, #02-16 Gleneagles Medical Centre, 6 Napier Road, Singapore, 258499, Singapore. 

In this great little slow mo video we see some things. Do you ? … The Perfect Runner.

1. First clips….. awesome toe extension through the entire swing phase all the way into early contact phase.  You have read here before on our blog entries how critical toe extension is for stable and optimal arch contruction prior to foot loading. Suboptimal arch height can mean that pronation loading occurs in a suboptimal foot tripod posturing and can mean difficulties controlling the normal end point where pronation should stop and convert back into supination to ensure rigid toe off.  (It is kind of like two runners in a 100m sprint. One starts at the line off the blocks and the other gets to start 1 second earlier 10 meters back from the line and gain speed towards the line before the gun goes off.  This is what it is like to start pronation prematurely, or with a suboptimal arch, the starting line where things are fair to all parts has been moved. The foot (the other guy in the race) doesnt have a chance.  Maybe a bad example but you catch the drift we’re surfin’ here.)  Back to our point, Niobe has great running form and great technicals.  Great midfoot strike, yes a little forefoot here but that is what happens when you are barefoot naked on hard surfaces. You have to get good form before you can clean up the technicals.  We spend alot of time on the technicals of running once form is clean. It is what makes the difference between 2nd place and a winner. And it is these little things that mushroom into nagging injuries over time.  We cannot express enough how important toe extension range and strength is for proper foot function and a strong neutral foot tripod.  We rarely have to address long toe flexor strength, short flexor strength yes, but not long.  Toe curls, towel scrunches, picking up stuff is not on our list of homework.

2. Second clip. He is skirting the issue of cross over without going too far. He could do a bit better but all in all pretty decent.

3. Emmanual Pairs, big dude ! No cross over. Awesome form.

4. Krysha Bailey. Long jumper. As with all sprinters, no cross over, beautiful form.

Just some easy topics and viewing for a Saturday blog post.

Have a good day brethren !

Shawn and Ivo

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In our ever popular; ask the Docs, here is another question from a reader
Transverse Arch

How would one go about “rebuilding” their transverse arch? The latter is pretty much convex. This also accomapnied by very tight long toe extensors (as evidenced by their tendons being very prominent at the top of my foot and my toes being curled at rest) and have suffered on and off from Morton’s neuroma. The ball of my shoes (right in the middle) is where the insoles of my shoes see the most wear. It’s not a huge concern of mine, but I would like to deal with this. I’ve suffered several ankle injuries (as a basketball player) and although I’ve tried orthotics in the past (for the neuroma), I’ve relied mostly on minimalist footwear (except when playing ball of course…). I know some rehab would be in order and would likely work. I’ve “reconditoned” my big toe abductors in the past and can even cross my second to over my big toe, so am just looking for some direction.

Thanks

E

 

Hi E

As you probably are aware, there are 3 arches in the foot: the medial longitudinal (the one most people refer to as the “arch”, the lateral longitudinal (on the outside of the foot) and transverse (across the met heads).

Your collapsed transverse arch seems like it may be compensated for by a rigid, probably high medial and lateral longitudinal arches. This creates rigidity through the midfoot (and often rear foot) and creates excessive motion to try and occur in the forefoot. Depending on how much motion is available, this may or may not occur.

You don’t seem to be able to get your 1st metatarsal head to the ground to form an adequate tripod, so you are trying, in succession, to get some of the other, more flexible ones there (thus the wear in the “ball” of the foot you noted). This results in increased pressure, metatarsal head pain, possibly a bunion and often neuromas.

From your description, you actually have very weak long toe extensors (and possibly some shortening) which is causing the prominence of the tendons, along with overactivity of the long flexors (and thus the clawing) in an attempt to create stability. I am willing to bet you have tight calves as well (especially medially, from overuse of the gastroc to control the foot) and limited hip extension with tight hip flexors.

The foot tripod exercises are a great place to start, as well as heel walking with the toes extended and walking with the toes up (emphasizing extension, which counteracts the flexors). Stay away from open back shoes and flip flops/sandals; continue to go barefoot and get some foot massages to loosen things up. Maybe use one of those golfballs to massage the bottom of the foot when you get off the course and get some golf shoes that aren’t quite so rigid.

Ivo and Shawn. Still middle aged. Still bald. Still good looking….

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Biomechanical and Clinical Factors Related to Stage I Posterior Tibial Tendon Dysfunction.     Rabbito M, Pohl MB, Humble N, Ferber R.

CONCLUSION:

The increased foot pronation is hypothesized to place greater strain on the posterior tibialis muscle, which may partially explain the progressive nature of this condition. J Orthop Sports Phys Ther, Epub 12 July 2011. doi:10.2519/jospt.2011.3545.

 

What the Gait Guys say about this article:

Do these results really surprise us? The Tibialis posterior (TP) is one of the more important extrinsic arch stabilizing muscles. It is a stance phase muscle that fires from the loading response through terminal stance. It ‘s proximal attachments are from the posterior aspect of the tibia, fibula and interosseous membrane and its distal attachments are the undersurface of all the tarsal’s except the talus and the bases of all the metatarsals except the first.

Since the foot is usually planted when it fires, we must look at its closed chain function (how does it function when the foot/insertion is fixed on the ground), which is predominantly maintenance of the medial longitudinal arch, with minor contributions to the transverse metatarsal and lateral longitudinal arches; flexion and adduction of the tarsal’s and metatarsals, eccentric slowing of anterior translation of the tibia during ankle rocker. It is also an external rotator of the lower leg and is the prime muscle which decelerates internal rotation of the tibia and pronation. As the origin and insertion are concentrically brought towards each other during early passive heel lift it becomes a powerful plantarflexor and inverter of the rearfoot.  There is also a  component of ankle stabilization via posterior compression of the tarsal’s and adduction of the tibia and fibula.

Alas, there is soooo much more than the typical open chain function of plantar flexion, adduction and inversion. Perhaps it is some of these other, closed chain functions, that cause the “progressive nature of the condition”?

We remain…The Gait Guys…Going above and beyond basic function and biomechanics.


Even cadaver feet speak volumes...

We hope you are thinking about muscles in a CLOSED CHAIN fashion, rather than open chain. In other words, when the foot is on the ground, it becomes the fixed point and the more proximal portion is the moveable portion. This paper shows (as Dr Allen did in his most excellent youtube video about foot function   http://youtu.be/TyRE9dReVTE  ) that the abductor hallicus is a dynamic elevator of the arch, in addition to being a great toe dorsiflexor and rear foot inverter!

Yup..we are definitely Gait Nerds….

Follow up post on yesterdays FOOT TRIPOD VIDEO
Good Day Fellow foot geeks !
Yesterday we posted a quick video  of a young  teenager who came to us for orthotic prescription.  As you  can see in the early part of the video he had a flat foot posturin…

Follow up post on yesterdays FOOT TRIPOD VIDEO

Good Day Fellow foot geeks !

Yesterday we posted a quick video of a young  teenager who came to us for orthotic prescription.  As you can see in the early part of the video he had a flat foot posturing and increased foot progression angle (feet pointing too much east and west). 

The increased foot progression posturing can be a problem, and accentuate pronation strategies,  particularly if it is outside the normative values of 5-15 degrees. This is because during midstance the limb is internally rotating.  If the foot progression angle is increased as the limb internal rotation occurs while the body mass is progressing over the foot in midstance, the positioning of the medial tripod of the foot is far off the forward/sagittal progression line (the direction of walk). When the tibia and femur internally rotate on such a foot posturing the degree of pronation is accelerated and accentuated. In another way of explaining it, the subtalar joint is almost falling medially outside of the tripod boundaries and thus cannot be controlled by the tripod. It would be like placing a camera directly on the letter “c” in the triangle diagram above, where the points of the triangle represent the positions of the camera tripod legs. The camera is at risk of tipping over because the mass of the cameral is not within the solid boundaries of the triangle.  In the foot, these tripod leg points would be represented by the 1st and 5th Metatarsal heads and the heel forming a triangle.  The goal is to stabilize the tripod on level ground and place the camera  (foot) in the middle of the tripod for maximal stability.  But, when the foot progression angle is increased, the triangle and foot position take on the triangle appearance above, risking pronation excesses.

The problem is that many folks do not know they have developed this problem posturing until symptoms occur.  This young lad was brought into our offices by an aware mom who had heard of similar successes we have had with other children and adults. 

It took all of 10 minutes to retrain his awareness of the foot tripod and posturing of the feet underneath the body (where he noticed that he could not pronate as much as seen at the end of the video clip).  HE did awesome as you can see.  For the first time in his life he saw an arch and knew how to correct his foot posturing. He became aware of the use and need for good toe extension to raise the arch (a phenomenon known as The Windlass Mechanism of Hicks).  The last stage would be to help  him retrain these strategies in gait and various movements. 

We will see if we can find that video somewhere.

Bottom line, …….did this kid need an orthotic……. NO !  It would have kept absent the strength development of the muscles needed to make the correction you see in the video.  This kid now has a fighting chance to develop normally.

Hope this helps to explain what was going on in yesterdays video.

We are………foot nerds…….

Shawn and Ivo

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Foot Arch Question: Sent in from one of our readers

How would one go about “rebuilding” their transverse arch? The latter is pretty much convex. This also accomapnied by very tight long toe extensors (as evidenced by their tendons being very prominent at the top of my foot and my toes being curled at rest) and have suffered on and off from Morton’s neuroma. The ball of my shoes (right in the middle) is where the insoles of my shoes see the most wear. It’s not a huge concern of mine, but I would like to deal with this. I’ve suffered several ankle injuries (as a basketball player) and although I’ve tried orthotics in the past (for the neuroma), I’ve relied mostly on minimalist footwear (except when playing ball of course…). I know some rehab would be in order and would likely work. I’ve “reconditoned” my big toe abductors in the past and can even cross my second to over my big toe, so am just looking for some direction.
Thanks


Our Response:

As you probably are aware, there are 3 arches in the foot: the medial longitudinal (the one most people refer to as the “arch”, the lateral longitudinal (on the outside of the foot) and transverse (across the met heads).

Your collapsed transverse arch seems like it may be compensated for by a rigid, probably high medial and lateral longitudinal arches. This creates rigidity through the midfoot (and often rear foot) and creates excessive motion to try and occur in the forefoot. Depending on how much motion is available, this may or may not occur.

You don’t seem to be able to get your 1st metatarsal head to the ground to form an adequate tripod, so you are trying, in succession, to get some of the other, more flexible ones there (thus the wear in the “ball” of the foot you noted). This results in increased pressure, metatarsal head pain, possibly a bunion and often neuromas.

From your description, you actually have very weak long toe extensors (and possibly some shortening) which is causing the prominence of the tendons, along with overactivity of the long flexors (and thus the clawing) in an attempt to create stability. I am willing to bet you have tight calves as well (especially medially, from overuse of the gastroc to control the foot) and limited hip extension with tight hip flexors.

The foot tripod exercises are a great place to start, as well as heel walking with the toes extended and walking with the toes up (emphasizing extension, which counteracts the flexors). Stay away from open back shoes and flip flops/sandals; continue to go barefoot and get some foot massages to loosen things up. Maybe use one of those golfballs to massage the bottom of the foot when you get off the course and get some golf shoes that aren’t quite so rigid.

Hey everyone. Have a Great 4th of July!

The Gait Guys

Research to support that we are on target !

CONCLUSIONS AND CLINICAL RELEVANCE:

The abductor hallucis muscle acts as a dynamic elevator of the arch. Understanding this mechanism may change the way we understand and treat pes planus, posterior tibial tendon dysfunction, hallux valgus, and Charcot neuroarthropathy. (see our video attached, it is much of what we talked about in this video just a few months ago).

*From the article: “Most studies of degenerative flatfoot have focused on the posterior tibial muscle, an extrinsic muscle of the foot. However, there is evidence that the intrinsic muscles, in particular the abductor hallucis (ABH), are active during late stance and toe-off phases of gait.

RESULTS:

All eight specimens showed an origin from the posteromedial calcaneus and an insertion at the tibial sesamoid. All specimens also demonstrated a fascial sling in the hindfoot, lifting the abductor hallucis muscle to give it an inverted ‘V’ shaped configuration. Simulated contraction of the abductor hallucis muscle caused flexion and supination of the first metatarsal, inversion of the calcaneus, and external rotation of the tibia, consistent with elevation of the arch.

http://www.ncbi.nlm.nih.gov/pubmed/17559771

Foot Ankle Int. 2007 May;28(5):617-20.

Influence of the abductor hallucis muscle on the medial arch of the foot: a kinematic and anatomical cadaver study.

Wong YS. Island Sports Medicine & Surgery, Island Orthopaedic Group, #02-16 Gleneagles Medical Centre, 6 Napier Road, Singapore, 258499, Singapore. yueshuen@yahoo.com

The Gait Guys: Some strategies in Controlling the Foot Arches and Big Toe

As promised. We fixed the volume.  Less hiss next time. Enjoy

Dr. Shawn Allen of The Gait Guys speaks about proper stabilization of the medial foot and arch. Muscle specifically discussed are a team: FHB (flexor hallucis brevis), AbDuctor hallucis, and tibialis posterior. He discusses the functional anatomy, normal and pathologic movement patterns of the arch and first ray complex and big toe (hallux). His foot’s ability to show the optimal patterns for the arch and hallux are excellent examples. Follow up videos and DVDs will show more details you need to know, and some of the exercises he and Dr. Ivo Waerlop use to restore a foot that has lost these abilities. The DVDs are in the works. Take their lectures and CME on www.onlineCE.com. Visit them at www.thegaitguys.com and on their facebook PAGE & Twitter of the same name for daily feeds of unique things.