What’s your Foot Type? : Part 2

Welcome to Monday! Here is the next in the series…

Rearfoot valgus.

Remember the foot tripod? It consists of the the 3 points: the base of the 1st metatarsal (under the sesamoids), the base of the 5th metatarsal, and the calcaneus. In this foot type the rear leg of the tripod is compromised as the rear foot collapses medially (the heel or calcaneus,  everts or moves laterally) causing subsequent collapse of the arch and midfoot.

This foot type causes an excessive internal rotation strain on the lower kinetic chain, often with collapse of the knees inward (genu valgum or “knock knees”). Due to the midfoot collapse, the deep calf muscles are typically overused and strained leading to medial ankle region tendonopathies, as they attempt to slow the rate of pronation and arch collapse.

This foot type has a difficult time going from pronation to supination to prepare for a rigid foot push off in the propulsive phase. Because the lower limb is internally rotated so much, the external rotators are over burdened leading to fatigue and weakness of the glutes and shortening of the TFL, leading to the chronic IT Band syndromes. Low back pain is common because of forward tip of the pelvis.

2 down, 3 to go!

Confused between the ear?

Have no fear. Shed no tear.

Our shoe fit program is almost here!     (Everyone has a little Dr. Seuss in them)

The Shoe fit functional testing module (also available separately from the 3 part program) discusses foot types in more detail.

The Gait Guys: promoting foot and gait competency everywhere!

Gait, Arm Swing and Reorganizing the Brain→

When we injure a body part there is a price to pay. The brain takes note of pain and usually uses its backup plan of neurologic inhibition or alteration of a motor pattern to protect that injured area and allow it to heal by moderating or altering the forces and demands upon said tissues.

This is a mechanism we need to have in place. But if we do not heed its warnings to dial things back and rest, recover and heal the brain will make alternative changes.

In this neurologically based article linked above in the title, the authors discuss several important things.

“Getting a cast or splint causes the brain to rapidly shift its resources to make righties function better as lefties, researchers found.
Right-handed individuals whose dominant arm had to be immobilized after an injury showed a drop in (brain) cortical thickness in the area that controls primary motor and sensory areas for the hand, Nicolas Langer, MSc, of the University of Zurich in Switzerland, and colleagues reported.
Over the same two-week period, white and gray matter increased in the areas that controlled the uninjured left hand, suggesting "skill transfer from the right to the left hand,” the group reported in the Jan. 17 issue of Neurology.
The findings highlight the plasticity of the brain in rapidly adapting to changing demands, but also hold implications for clinical practice, they noted.“

This article highlights the rapid changes in motor programs that occur. It does not take long for the body to begin to develop not only functional adaptations but neurologic changes at the brain level within days and certainly less than 2 weeks.

We tell our patients, if pain does not go away fairly quickly, that we need to get on top of the injury quickly. That is not to say you need to reach for the phone every time you  have pain but you need to heighten your awareness of the injury’s status and  you need to make sure you are not driving session after session of training into a festering injury. If you do not let something heal and recover, the brain will find a way around it.  And it will imprint that new motor pattern into hard wiring if you do not heed the warning signs.  This new wiring is a compensation pattern. And the longer it is there the more the neurologic pattern becomes embedded by layerings of myelin coating.  Which means that in the future, if you fatigue or injury another local tissue, this old compensation pattern is waiting in the shadows looking for an opening to rear its ugly head for old times sake. 

Shawn and Ivo …  Two plastic fellas, just like everyone else. 

Email from a reader: Chronic IT Band and Plantar Fasciitis

I have been reviewing your Youtube videos and blog posts over the last few weeks, I am a triathlete suffering from plantar fasciitis and ITB issues, and I’m not really close to a major center where I can get treatment so I’m self educating. I’m very interested in the videos you have about function of the foot, and how the toes relate to the arch, fascinating! You mention exercises for the feet, to help the muscles function and learn to work separately. I was wondering if you have any of these exercises posted online, I am not able to hold the arch position or use my toes separately, I think these movements would go a long way to helping me figure why I’m having issues with the PF. Great job on all the info, I love being able to access info like you guys have online, makes me want to learn more… thanks!!

 

 

Becky H

AB, Canada

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Dear Becky:

Sorry to hear about your chronic issues.  Make sure you evaluate your glutes. The pelvis must remain relatively quiet and not tip forward or backward (anterior or posterior tilt) during all forms of ambulation. When it tips more forward the glutes become challenged and can become inhibited. When inhibited internal rotation of the hip minimizes or is lost and the ITBand tightens to attempt to drive that internal rotation. It is a good internal rotator as is the anterior g. medius and coccygeal division of the glute maximus (hence the glute connection).  This will put stain on the patellofemoral joint and may cause tracking issues or lateral knee regional pain (or ELPS….. excessive lateral patellar pressure syndrome).  Additionally, when the foot tries to pronate more to drive more internal limb rotation (because it is obviously not happening at the hip in this scenario) the plantar fascia can become strained because of the pronation lengthening of the longitudinal arch of the foot.

Regarding the foot exercises……. they are coming….. we just need time. We would pay for more time, but we cannot seem to find it on amazon or ebay.  If anyone is selling, we will line up to buy !

thanks for your email question.

Keep the emails coming. Those of you who have emailed us recently or in the past, we  have received them and they are being answered in length in the podcasts we are about to launch. They are coming, you will love them.  It just comes down to editing time.  There is that “time” word again !

A runner with an inverted heel and functional hallux limitus

Here is a long Q and A Dr. Ivo had with a client who emailed us quite awhile back. It is very informative and it has links to the readers gait videos.  We hope you find this informative.

Q:    I am a long time distance runner (33 years of marathoning so far ) that has had back and hip problems since the 1980’s. I have tried all sorts of therapies, but I have a funky stride on my left side. I started going to an ART doctor this week. He said I have an inverted heel on the left side and functional hallux limitus on both sides, however on the left side (with the inverted heel) the foot pronates down to get the first metatarsal to touch the ground. So my left heel supinates and the forefoot pronates and does this strange movement that creates havoc with my leg and hip (at least that is my understanding).

By checking out your videos, is rearfoot varus the same as inverted heel? or is there something else you can point me to. I am getting ART treatment for the heel, mobilizations on the foot, and the doctor suggested cutting out part of a Dr. Schools ¾ foot insole underneath the first metatarsal to see if this makes the toe and metatarsal work.

You can see short videos of my funky left foot stride here: http://recoveryourstride.blogspot.com/2010/06/inverted-heel.html
Any thoughts or advice would be much appreciated.
Jim

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Hi Jim

Thanks for the post and video. I apologize for the late response. It was very helpful as we use it to analyze most athletes. I am not sure if you can email the original file; it would make an excellent teaching tool.

To answer your question, an inverted heel is usually synonymous with rear foot varus deformity. The latter technically means that you are unable to evert your heel to zero degrees. Eversion is a necessary component of rearfoot pronation and if it cannot occur there, it will occur in the midfoot or forefoot. I would need to see a picture of your foot to tell you where yours is probably occurring; my guess is the forefoot. It appears you may also have a difference in the length of your legs as well, either functional or anatomical.

You have external tibial torsion. This means the angle your ankle makes with your lower leg (ie the angle formed by a line bisecting the medial and lateral malleolus and a straight one) is in excess of 25 degrees (it is usually 20-25 degrees). It is a congenital condition that appears largely unilateral in your case. Internal tibial torsion would be when the angle is less than 20 degrees and the foot points in.

The limb buds appear somewhere near the end of the 5th week of embryological development and continue to develop into the paddle shaped vestiges we have come to know as hands and feet over the ensuing weeks. At around 7 weeks, the axes of the upper and lower extremity buds are parallel. They then bend 90 degrees (forming elbows and knees) and stearicaly rotate opposite one another, so that the ventral (or flexor) surfaces of the arm and forearm face anteriorly in norma anatomica and the ventral (or flexor) surfaces of the lower extremities face posteriorly. So in other words, this is a genetically determined sequence of events, which can sometimes (but rarely) run awry, with no influence from muscle activity or inherent osseous torsions.

This condition means that when your knees point straight ahead, the foot points to the outside; if you point your foot straight, the knee points to the inside (both are demonstrated on your video). This creates a problem because if you straighten your foot, anatomical constraints do not allow your ankle to dorsiflex (ie extend) and this is another necessary component off pronation. If the pronation cannot occur here, shock absorption will need to occur elsewhere (ie your knees, hips and spine; see our post entitled “learning to walk properly”). This is ultimately what caused your hallux limitus.

The 1st ray cutout you are describing may help; however if you have a hallux limitus, you probably do not have enough range of motion available to get the head of the 1st metatarsal down to the ground to make an adequate tripod. ART, exercise, and mobilization may help but you must be diligent. If conservative measures fail, you may need an orthotic, custom built by someone who understands the problem and can help alter your mechanics accordingly. Orthotic therapy should help to make the problem less and less, and should be used in conjunction with exercises, to insure your prescription is becoming less and less and you are not becoming dependent on them.

Hope that helps.

Dr Ivo

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Thank you for the reply Dr. Ivo,
I assume you are referring to the Youtube videos of my running. I can send them to you. Which one (ones) do you want. I have to study your reply as there is a lot in there and a lot that makes sense as to what I have noticed.
You also wanted to look at pictures of my feet. I put some up a couple of years ago when I was trying to figure out what was going on with them and attempting various solutions of my own. Would these be adequate (look down the page) or were you thinking of something else: http://recoveryourstride.blogspot.com/2008/06/if-foundation-is-off.html

I have moved away from the cut out insole that I described earlier and had an insole specifically made for HFLput in my shoe yesterday by the Doctor who is well-known for his work with HFL. I guess Dr. Dananberg would be the best guy to see for this and fortunately his office is close by. http://recoveryourstride.blogspot.com/2010/06/functional-hallux-limitis.html

That is interesting and comforting that you infer that some can be weaned from the use of orthotics for FHL. Thanks again for your replay.
Jim

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You are welcome Jim.

I looked at your pictures. You can see in the 2nd one down that you invert the foot and have space between the 1st and 2nd toes (from trying to reach medially with your big toe and create a medial leg of your foot tripod). I was not sure you would do well with the 1st ray cutout, as it appears your foot doesn’t have the flexibility. You can also see the toes hammering (ie curling of the toes) to try and maintain some stability of your foot.

The 3rd picture shows your tibial torsion quite nicely, with your knee turned in and the 4th with the knee straight and foot toeing out (increasing the progression angle).

I would love the front and rear view video of your running. with your permission, I would like you to send these and allow us to use your photos from the site to create a teaching case. We will give you and your site full recognition.

Dr Dananberg is top notch. I knew him when I practiced in Gloucester, MA. You are in good hands.

Dr Ivo

Neuromechanics Weekly:

Gait Noise

Think of “Gait Noise” as those things which alter the sum total of all neuronal activity acting at a specific locus. Gait noise is all of the aberrant signals that distort the correct and most functionally desirable signal necessary for a clean gait.  Think of noise as the static found between radio stations, that irritating white noise that blurs out the perfect radio station from coming in clearly.  Gait noise is thus anything that impairs a clear sensory and motor signal to and from the central nervous system required for clean uncompensated gait. These definitions will help you understand where we are going with this.

1. Communication: Anything that interferes with, slows down, or reduces the clarity or accuracy of a communication. Thus, superfluous data or words in a message are noise because they detract from its meaning.

2. Quality control: Variability that may be caused by changes in the ambient conditions, faulty machine performance, or uneven quality of the material or human factor inputs.

3. Telecommunications: Random disturbance introduced into a communication signal, caused by circuit components, electromagnetic interference, or weather conditions. Also called line noise.

Gait noise is therefore very undesirable. It could be interpreted as seeing a foot turned out more than normal, more than the other side. Seeing that compensation is a motor impairment and an undesirable motor pattern, but it also sends aberrant sensory information back into the nervous system. Bad information in, bad information out, and a viscous cycle ensues.  Gait noise can occur from a total knee replacement, from a scar, from a sprain, a broken bone, from the numbness of a diabetic neuropathy etc.  These all cause impairment of the sensory-motor-sensory loop.  Gait Noise theoretically could occur anywhere along the neuraxis (spinal cord and brain-brainstem) or even the peripheral nervous system, but it makes most sense to think of it happening where neurons congregate; most likely at synapses, especially at the spinal cord level. The wiring of the nervous system extends to all tissues, so the noise can occur anywhere for almost any reason.

In the words of Dr Ted Carrick, “Is the lesion at the receptor, the effector, the peripheral nerve, the spinal cord, the brainstem, the thalamus, the cerebellum or cerebrum?”  Where is the problem in otherwords ?  Lets explore how this relates to “Gait Noise”.

Today lets look at the receptor. Receptors are the information gatherers of the nervous system. Think of your 5 senses (vision, smell, taste, sound and touch). These are all subserved by receptors. Vision and touch seem to most affect gait and movement. This post will concentrate on touch.

Touch encompasses not only physical touch but also proprioception (see here for review of proprioception and receptors). These receptors: Pacinian corpuscles, Merkel discs, end bulbs of Krause, bare nerve endings, joint mechanoreceptors, muscle spindles and Golgi tendon organs are all included here. These sentinels provide the central nervous system (CNS) with mechanical environmental information, for comparison with that same information (there is much redundancy in the CNS) and other environmental information (balance, vision, hearing, etc), so that you can formulate (consciously or subconsciously) a response.

In short, there are multiple systems converging, in this case, on the peripheral receptor. Remember, receptors can be activated in may ways. A touch receptor could be activated not only by touch, but also by heat, cold, pressure, or even chemical (metabolic or toxic) means. Just like you may be a great tennis player, you could probably play racquet ball, handball, or football, even if you never played before. You may not excel, but you could get by. Receptors are no different; they may be BEST activated by touch, but other means could certainly do the job. This inadvertent activation creates receptor bias, as we like to call it “noise”, and that information is sent to the CNS for processing. If a touch receptor is activated, it is activated, and the CNS  sees it as an activation, whether it is intentional or not. These mixed signals are then processed along with everything else, creating “noise”.  And the noise might not be a desired signal. And these signals can be what initiates a gait change, a compensation, whether it be from information mis-processing or a strategy to cope.

Think of the application to your gait analysis, next time you are seeing something that you think you shouldn’t be seeing.  This is the problem with video gait analysis (as we take a moment to pound the wall on this topic ONE MORE TIME !).  What we see on a video analysis is not necessarily the problem, nor does what you see warrant a correction or a specific shoe. What we are seeing on video is their coping strategy after all of the CNS signals (noise and non-noise) have been processed, it is what they can do with what is available to them and with what makes most sense to the brain.  We have said before, as a classic example, that an over pronating foot might be a necessity to compensate for lack of internal hip rotation because the brain deems that functional pathology as more damaging at the hip than the hyperpronation at the foot.  Who are we to deem that the foot needs an orthotic or a stability shoe because of what we see?  Who are we to think that we can outsmart all the sensory-motor calculations of that persons brain without knowing all of the functional limitations of their body ? Perhaps if we take an hour to assess our client, and then see them for another visit or two, we can then correlate the gait video, our findings and our corrective work and then truly qualify a logical reasoning.  But this is a far more difficult game that this simple gait video or foot plantar pressure digital foot mapping nonsense.

Ivo and Shawn; the voices in your head, helping you sift out the noise.

The Chef: Another abnormal gait pattern in celebrity chef and The Travel Channel’s Anthony Bourdain.

It was just a few nights ago after a 13  hour day with patients that I got home and climbed into bed, looking forward to flipping through channels to find something to alter my brainwave state. I needed to find something that would allow me to dial down into a slumber.  Much to my happiness I found one of my favorite shows, “No Reservations” with my favorite chef.  I get a real kick out of Tony. This is one smart dude. He is pretty slick with the english language.  Did you ever get to read his New
York Times best seller “Kitchen Confidential”?  What a killer book. We recommend the audio book read by the author himself.  It turned the restaurant scene upside down.  Has anyone ever told you not to order fish Monday through Thursday ? It is all in the book.  Why else do I love Bourdain?  His command of the english language is exceptional, and creative.  For example, he once said, “what would it be like to be a meat-filled Pinata at a Pit Bull convention?”.  Things like that stick with you.

Anyhow, so there I am lying in bed dozing off, listening to Bourdain talk about Mozambique and there he is in all his slender glory walking down the street with his sidekick Samir.  “Red Alert, Red Alert ! "  The clinical brain snaps back on.  Dammit !  Knowing very well I had to rewind the cable box to see it again, but knowing I was slowly descending into deeper brainwaves, I quickly rewind and grab my iphone to record the gait you see above.  You see, when you are a gait nerd like us, nothing escapes you when it is this obviously wrong. It is a disease; trust us.  We cannot go anywhere anymore without noticing pathologic gait.  It appears we cannot even watch a cooking show. And since we live on a planet where everyone walks, it must be a penance for something we must have done in another life.

Onto Bourdain’s gait. 

Look at Tony’s circumducting feet compared to Samirs (on the right).  Samir clearly engages pelvis lift on the swing leg side which is typically brought on by engagement of the hip abductors (g. medius) on the stance leg side. This lift on the swing side allows the swing leg to have ample room to pendulum through without having to prostitute the knee or foot posturing.  The knee and foot simply sagittally hinge through, this is economical gait.

Bourdain on the other hand shows little if any swing side pelvis lift driven by stance leg hip gluteus medius engagement.  This creates a clearance problem for the pendulum swing leg.  So now the problem becomes how to get the leg to swing through without catching the toes and foot. You must create clearance. Clearance can be obtained by:

1. generating opposite  hip abduction forcing the swing leg hemi-pelvis to lift
2. increasing hip flexion which will initiate a steppage gait. This will be combined with increased knee flexion. This is productive and necessary if you are climbing stairs or trying to unload a painful turf toe near the end of stance phase push off.  When seen in normal walking gait it may represent neurologic pathology.  But folks with hip problems or weakness will use it to get around to avoid tripping.
3. circumduct the swing leg hip. The act of swinging the leg outward and around will eat up the leg length.
4. circumduct the foot.

Bourdain is doing #4. It is a pretty lazy gait strategy, you can see it is lazy. It probably requires very little energy to flip the foot outside the normal ankle dorsiflexion foot swing progression.  What must be the cost to activating the peronei and the lateral toe extensors to flip that foot around like that ? Sure you can see that the knees are for a moment carried outside the sagittal plane but who cares, right ? 

There are a couple of concerns. One is that failure on a single step to generate sufficient foot/ankle circumduction will result in a foot catch and a fall.  Another is the trouble in always getting that circumducting foot to land precisely in the near sagittal plane. When you move the foot on an arc you really only have a narrow target to land the foot within the 5-15degree landing zone. Circumduct too far and the foot is in-toed and more rigid due to it being supinated during midstance, circumduct too little and the foot is more out-toed and increased pronation risk increases.  This goes for running as well.

Go back and watch Samir’s walk. Clean and done right, the swing leg is a passive pendulum. Tony’s is obviously different. Who knows, maybe he has bad hips ? Maybe it was always a struggle to walk normally. He is 6'4” so we cannot blame it on excessive height unless he lives in a house that has 6 foot ceilings, because then his strategy would be our gait of choice. It would be the only one that would effectively work !  Maybe that is it. Maybe he lives in Smallville ?

We don’t think so.  The only for sure way to know would be to get him on our exam table and see what parts he is not using. We would put big money on weak gluteus medius, bilaterally.  It is the one we see most often in this abnormal gait pattern.

Shawn and Ivo, tortured gait observers in a world of ambulatory pathology.

Welcome to our hell.

What’s your Foot Type?: Part 1

Ready for Monday Morning? This is the 1st of a 5 part series to get your week going and help get you in a “Gait Guys” frame of mind

Rearfoot varus

What if many of your nagging and seemingly un resolvable injuries as an athlete were from an undiagnosed foot type? What if every shoe, insert and orthotic you implemented in an attempt to help manage these problems was not the solution, but rather a means of “band aiding” the problem because your anatomy was compromised from the start? 

Wouldn’t it be nice to have some answers to all the questions you have as to why your interventions were less than optimal? Wouldn’t life be better if you knew that your anatomy was slightly left of center and that this was the true cause?  Life as an athlete sure would be more tolerable and perhaps, just perhaps, a life with fewer nagging injuries.

The main issue is that the majority of humans have less than perfect feet. The “perfect” neutral foot is one in which the rearfoot and the forefoot lie on the same plane, meaning that the forefoot and the rearfoot lie square on the ground when ankle and subtalar joint mechanics are neutral.  This insures the tripod of the foot (the base of the big toe, the base of the little toe and the center of the heel) remain on equal footing, creating a balance of power between the muscles and articulations.

There are many reasons at to why we do not all have perfect feet with pristine mechanics to run and walk on.  Some are genetic, some congenital, and some developmental. Regardless, as the saying goes “You have what you have, so why not make the best of it?”

In a nutshell, there are 5 basic foot types; two involving challenges to the forefoot, and two challenging the rear foot. These can be rigid and non adapting, flexible and adapting, or somewhere in between. The fifth type is the ideal of what we all hope to have. This 5 part series will help you to understand each and the biomechanics associated with the anatomical variant.

Rearfoot varus.

The rear foot varus is a foot that has the heel inverted, almost appearing as though the ankle is about to roll, like a common ankle sprain. Here the rear of the tripod is compromised. Because of this lateral shift of weight through the contact phase of walking or running, the foot is over supinated  (plantar flexed, inverted and adducted) at toe off.  The owner of this foot type usually has excessive use of the peroneal muscle group to fight this supinated tendency and prevent ankle sprains.  The 4^th and 5th metatarsals typically take on more stress, and are often painful. Loading the lateral aspect of the limb shifts the center of gravity and challenges stability in the frontal plane, often leading to hip problems, such as trochanteric bursitits and IT band friction type syndromes and knee/patellar tracking issues.

Confused? Have no fear. Our shoe fit program is almost here! The Shoe fit functional testing module (also available separately from the 3 part program) discusses foot types in more detail. Watch here on Mondays for a different foot type each week!

The Gait Guys: promoting foot and gait competency everywhere!

Keep Digging

We are often asked by coaches, trainers, runners, therapists or folks on the internet sending us video clips “What is wrong with this gait?” or “Why do I have pain?”. Sometimes, we are able to provide an explanation which seems too simple, but is often correct. Things usually are more simple than one makes them out to be.  It often corrects the immediate problem, only to have another crop up a few weeks later.

Why?

To paraphrase from the words of SHREK; peoples compensations are like onions; they have layers. It is not that you were incorrect, not at all.  You may have been correct for “that” issue.  But, uncovering and remedying one problem often leads us to the next weakest link in the chain.

We still have fond memories of Dr Ted Carrick grilling us in the post graduate neurology program “What is the longitudinal level of the lesion? Most pathologies occur at one locus; if you diagnose more than one, it is usually due to metastasis, multiple vascular occlusions, or clinical incompetence. Is the lesion at the receptor, the effector, the peripheral nerve, the spinal cord, the brainstem, the thalamus, the cerebellum or cerebrum”.

The information to glean here is that often we need to establish and limit our focus to ONE area where the problem could be, and sort out that issue first. This necessitates us thinking through the problem and coming up with ONE problem which could cause all the problems you are seeing. This applies to gait and motion assessment as well.

Think of the patient with right sided knee pain caused by patellar tracking issues. Is the retro patellar inflammation the cause? Not usually (unless there has been direct trauma), it is often the symptom (or compensation). Maybe the cause is a forefoot varus deformity causing abnormal knee mechanics because they cannot descend the 1st ray adequately. Maybe this is due to insufficient extensor hallicus brevis function, or is it the peroneus longus? Maybe it is due to a congenital deformity of the foot. Maybe it is due to a functional (or anatomical) leg length discrepancy. Or maybe it is a problem with the left shoulder affecting tandem arm swing with that leg ? … you get the idea.

Keep looking and digging until you have found the 1 THING that can explain what is going on. Maybe it’s the individual; maybe it’s their footwear. maybe it is remnants of unresolved factors from an old ankle sprain, old fracture maybe something else. Maybe a c-section scar disabling the abdominal wall and reducing the anchoring capacity of the abdominals into the hip thus impairing the quadriceps and thus knee tracking ? The possibilities are endless. If you can’t explain it by a single problem or fault, maybe it is time to run some blood work, send them for a vascular flow analysis, or more often than not; expand our knowledge base.

We are The Gait Guys… Two guys digging deeper and looking for the cause.

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Welcome to Friday Follies. Or should we say Friday Bloopers.

Here is a previously unreleased version of an intro to a review Dr Allen had done. Dr Ivo, knowing how Dr Allen feels about heavy metal, made this spoof.

Enjoy!

Ivo and Shawn

Retail Focus Thursday: The Lateral Flare

We recall that The lateral flare is part of the outsole, where it is elongated laterally (as opposed to medially, as in a medially flared shoe), to create stability.

Look at the above example (left above). Notice how the cushioning is different at the lateral aspect of the outsole; in this case: two densities. In this case, Nike Cesium, there is no lateral flare but plenty of entry zone cushion !  In this case this is to “ease the foot into pronation” (keep the foot longer in supination) and is considered a motion control feature (along with dual density midsoles and torsional rigidity, among others).

The typical lateral flare however, as seen in the middle picture drawing, can be a good thing and acts differently than the soft lateral entry zone of the Cesium above. The typical lateral flare will help to pronate the rearfoot, helping minimize the risk for ankle inversion; something you do not want especially when trail running where heel strike is sometimes more pronounced. The Nike above on the other hand, without the lateral flare, will keep the foot in supination longer, and tends to increase stresses to the lateral column of the foot.  Not a good trail running shoe example !

Typical lateral flares, speed up initial pronation (when walking we usually strike on the outside of the heel, as do some heel strike runners.  The flare creates a greater distance to travel in the same amount of time; again; see center pic above). It does not appear to increase total pronation or affect impact forces. It is a good idea for one problem, but often creates another. Not everyone can handle an increased speed of pronation effectively: these folks need to suddenly decelerate the medially spinning leg. What will do that? Most likely the glutes (max and medius); the vastus medialis (contracting eccentrically) and the anterior leg muscles (like the tibialis anterior, extensor digitiorum longus, extensor hallucis longus). You have probably been reading our posts for some time now. How many individuals have competency in these muscles? Not many.

Regarding the lack of lateral flare in the Nike shoe above, this feature has a tendency to “close” the knee medially and “open “it laterally. On the other hand, a typical laterally flared shoe will open the medial knee joint line and close the lateral but this does depend on the degree of tibial torsion and varum.  These lateral flare issues need to be strongly thought out when prescribing a shoe for a client.  This can be a double edged sword. Arthritis is most likely going to effect the medial (inside) knee 1^st so you will want to chose a shoe that does not compress that medial knee.  

The bottom line? Proceed with caution with ANY shoe that has a motion control feature and know what you are recommending.

A little lost? Have no fear;  the complete shoe fit program (with IFGEC certification if desired) is coming in the next few months. Watch here, on Facebook or Twitter for the announcement. What is the IFGEC you ask ? “The International Foot & Gait Education Council” , a group of experts brought together from around the world in a combined braintrust to further foot, gait, running form and shoe forward thinking.

The Gait Guys…Shoe Geeks Extroidinaire. Helping you help your clients make better shoe choices

Neuromechanics Weekly: PART 2:

Stretching increases strength in contralateral muscles?

Lots of cool links in this post. please try and find time to check them out.

Figure it out?  Ever wonder about some of the magic behind some of those manual therapy techniques that are out there ? Sometimes it is not magic at all !

There are 2 related reasons we can think of to cause this seemingly odd length-strength phenomenon (OK, there are more, but this is what we are going to cover today):

• Reciprocal Inhibition
• Crossed extensor reflexes/responses

We remember reciprocal inhibition (as demonstrated in LEFT picture above) is when we activate or stimulate a muscle, the Ia afferent from that muscle stimulates that same muscle to contract (this is how a simple reflex arc works) and, through an inhibitory interneuron, inhibits the antagonist muscle on the opposite side of the joint.

Remember, that Ia afferents go to muscle spindles (don’t remember? look here); they respond to LENGTH changes. Wouldn’t you say stretching affects length? If we were talking about the R tricep surae group, we would be inhibiting the R anterior compartment.

But wait, the article said it affects the opposite side….Of course, there is more…

The picture on the right shows the crossed extensor response or reflex (don’t remember? look here). In a nutshell, when you FIRE the flexors on one side, you INHIBIT the extensors on the same side (sound like reciprocal inhibition? It should… it is : ) You also FIRE the extensors on the opposite side while INHIBITING the flexors on the opposite side. (Yes, the opposite side extensors will inhibit the opposite side flexors as well. Yes, this is also reciprocal inhibition).

But wait, that means the opposite calf would be weaker, not stronger, right?

It would be weaker if being called upon to be used at that moment in time, BUT in the study, stretching increased ROM of the stretched calf 8%, with a 1% loss of ROM of the opposite calf (study summary).

Hmm… sounds like shortening to me. That would mean that those spindles (ie the opposite calf)  would be MORE RESPONSIVE to stretch (ie a change in length; and coincidentally, the Golgi’s more responsive to the tension change) . And what happens when we preload a neuronal pool? The likelihood of firing is increased (like doing a Jendrassik maneuver to increase a reflex). The rest is neural adaptation (strength gains initially are due to increased efficiency of the nervous system. For a review to see our video on this, click here)

Interesting that one of the comments on the article was “I don’t have the full text of the paper but a summary prepared by Chris Beardsley and Bret Contreras states that one of the mechanisms for crossover in the case of unilateral strength training is thought to be modulation at the spinal cord level.”   Could they be talking about reciprocal inhibition and crossed extensor responses?

Wow! Very cool! And to think, you knew the answer. We are proud of you!

Ivo and Shawn…Neuro Geeks too!  And applying it to gait, running and motor patterns of all types !

Neuromechanics Weekly: PART 1:

Stretching increases the strength in contralateral muscles?

The question is why (isn’t that always the question?). Applying your knowledge of neurology, can you figure it out?

Here’s a hint: There are at least 2 related reasons. See the pictures above and check back at noon for our theory.

Stew on this for an hour, seriously !   Engage your brain on this very important topic and we will see you in one hour.  For the next hour as you stretch, or stretch athletes, or patients or as you prescribe stretching as some homework to someone, think about how stretching one muscle creates strength in a contralateral muscles.  If you learn to use the power of the nervous system to your advantage you can get much better results.  The Gait Guys do.

Click above for the article

Video Gait Case: A troubled Youth.

This is a video of a teenage girl with chronic posterior knee pain. What do you see in her gait. Don’t cheat yourself. Before you read below see what you can see first and then drop your eyes down to our work below.

1. Heavy rear foot lateral strike. This is rearfoot inversion at its worst. This is considered rearfoot varus. Hyperpronators will often display the opposite, a rearfoot valgus. In this case, a heavy lateral strike leads to sustained lateral foot weightbearing which will mean she stays on the outside or lateral aspect of her foot too long and thus stays in supination.
2. The heavy lateral foot strike will often lead to knee hyperextension during initial contact and often continues throughout stance phase, as this is a position of stability for the joint. At the end of the video as her knees come into view you can see the degree of knee hyperextension (somewhat). This may remind you of our blog post months ago on anterior knee pain (Anterior Meniscofemoral Impingement Syndrome). Such an anterior pitch of the pelvis and lumbar extension can obviously lead to shortness and shortness-weakness of the psoas and rectus femoris to name just a few.
3. This type of gait will often lead to an accentuated lumbar spine lordosis curve (functional usually) with an accentuation of the anterior pelvic tilt and resultant inhibition of the lower abdominals. This furthers the knee hyperextension and thus the cycle continues (the knee hyperextenion perpetuating the anterior pelvis and weak abdominals which then drive continued knee extension). Bringing these topics and blending them with items in #2 will naturally limit the degree of hip extension (since the extension of the limb is occurring in the lumbar spine) and lead to inhibition and weakness of the gluteus maximus.
4. Quite frequently a heavy lateral rear foot strike results in a heavy pronation event at the forefoot loading period (forefoot pronation) particularly when the foot progression angle (turn out) of the feet is large. We DO NOT see this here. However, in these cases one had better have exceptional medial foot tripod skill, endurance and strength (S.E.S once again) as well as great strength in the long and short big toe flexors (FHL, FHB) to help anchor that medial tripod because the forces that are coming into the forefoot in those case are like a rhino at feeding time. However, in this case, there is a plantar flexed 1st ray posturing of the forefoot. A trained eye can see some of the functional characteristics of this forefoot type, but you really must confirm its presence on a clinical examination mainly because you want to know if it is a rigid or flexible forefoot variant. A plantarflexed 1st ray is sometimes found paired with a rearfoot varus, as the foot is trying to find the medial tripod. A forefoot valgus is also possible, but this usually results in the medial foprefoot striking the groung 1st, as opposed to the lateral, as we see here. These people often have great difficulties getting off of the outside of the foot and onto the medial foot to adequately toe off the big toe. This is sometimes referred to as an apropulsive gait.

Wow, all this from some bad gait skills and some minor foot variances huh ?! Yup.

Which brings us to shoes. Wouldn’t it be nice to be well versed on all these issues before you slap her into a neutral shoe ? Because she clearly does not need a stability shoe; pronation is absent in these feet. So, do you pick a neutral shoe with a soft lateral heel crash zone ? How about one with a lateral rearfoot cut out (or “entry” as it is often called? What about no cut out ? Would she do better in a straight lasted shoe or curved ? There are plenty of questions, more than just these. But for this case…….lets stop here and answer just these few for now.

1. no soft lateral heel impact crash zone with this type of rear foot
2. use a shoe with no cut out (the beveled cut out at the lateral heel will promote more sustained lateral foot weightbearing). Shoes without a cut out (or entry) will help to drive that heel into eversion and pronation but you had better make sure you have changed their gait and ensured adequate medial foot tripod strength, because remember those types of feet will be driving into that medial forefoot in a major hurry with aggression…… but, thankfully this is not the case here.
3. Choose a Straight lasted shoe in this case. A more curve lasted shoe will promote more and faster pronation into that forefoot, there is already enough !

There is so much more to this game that simply promoting natural running form or natural walking form. So much more than simply dropping someone to a zero drop or minimal shoe. As we say, it is often not the shoe but the thing you put in the shoe……. but you have to know what shoe you put on the foot and how it is going to react to the foots abilities and its challenges.

Our Shoe Fit program is getting closer and closer to a release date. Those that have been through our program, formally or informally will have the knowledge and skills to dissect a case like this and make some good assessments and choices.

Shawn and Ivo. Gait Geeks, Shoe nerds, Running form teachers, …….. and halfway decent doctors too.

A brief look at the effect of shoe drop on abdominal engagement and the relation to low back pain.

Enjoy!

Ivo and Shawn

When Gait is lost. New developments in mobility.→

We live in pretty amazing times.  This device will change some people’s lives. As long as you have sufficient limb function this is a nice alternative to a wheelchair.

We found this while searching for another image and thought it fitting for a Friday:

“May you walk barefoot in joy and empathy, or shod with the shoes of your choice (or your charity), and may your path be the one that takes you where you need to go”

Have a great Friday

Ivo and Shawn

source: http://kathleenkirkpoetry.blogspot.com/2011_03_01_archive.html

Are you "running" yourself into hormonal trouble ?→

Do those 40+ mile weeks do only good things to your body or could they be hurting you ? Is all this exercise catabolic ? Have you ever heard of hypothyroidism ? How about screwing up the hypothalamus-pituitary-adrenal axis ?   If you are a chronic exerciser you might want to read on.

Define catabolic: The metabolic breakdown of complex molecules into simpler ones, often resulting in a release of energy.

“I tried to rescue my Jessica from the clutches of the cardio contingent, but to no avail until a month ago when she called to tell me that a blood test had confirmed her doctor’s suspicion: she had hypothyroidism — her body no longer made enough thyroid hormone. Her metabolism slowed to a snail’s pace and the fat was accumulating. Now she had a culprit to blame, it wasn’t the cardio causing her problems, it was her body rebelling. When Jessica asked my advice, I told her to do two things: schedule a second test for two weeks later and until then, stop all the goddamn running.”

-From the article, Women Running into Trouble.  By John Keifer, on Elitefts.com

There are plenty of studies showing that chronic cardiovascular workouts may help to shut down the thyroid gland and its production of T3 thyroid, the body’s metabolic regulator. If you need those references, the 2 articles in this blog post, one by Keifer and one by Kresser, have plenty to just get you started.

Wait a minute Gait Guys, months ago you wrote about gluten in my food affecting the thyroid and now possibly longer cardio exercise as well ? Yup, there are suggestions that it can be the case in many people. But that doesn’t mean you need to freak out. You just need to be aware and be smart.  

First, lets review the gluten thing one more time for our new readers. (if you want to read our gluten ataxia article from moons ago, here it is). Several studies show a strong link between AITD (autoimmune thyroid disease (both Hashimoto’s and Graves’)) and gluten intolerance. The link is so well-established that researchers suggest all people with AITD be screened for gluten intolerance, and vice versa. And some experts will even tell you to not trust the intolerance screens, rather just stay away from gluten all together. 

AITD is a case of mistaken identity says Dr. Kresser in his article. He mentions that

“the molecular structure of gliadin, the protein portion of gluten, closely resembles that of the thyroid gland. When gliadin breaches the protective barrier of the intestinal gut, and enters the bloodstream, the immune system tags it for destruction. These antibodies to gliadin also cause the body to attack thyroid tissue. This means if you have AITD and you eat foods containing gluten, your immune system will attack your thyroid”

Ok. Back to exercise now. 

OK Gait Guys you have my attention now.  So, you are telling me that regularly repeated sustained exercise can also possibly affect me as well ?  The answer is yes.  There is some reasonable and growing research on this topic, so just educate yourself and make your choices and watch for signs.

Here is how it works.  T3 is the body’s metabolic regulator and it can crank up to generate heat and fuel production through catabolic processes generating energy.  It can also down-regulate (hypothyroidism) to slow the body’s metabolism and lower body core temperatures. This slow down can cause weight gain and lethargy even if the person is active and exercising (Do you ever go to the gym and see those folks who are always on the treadmill or ellipticals, never seeming to lose weight ? Sure they could be eating 3 square meals at Crispy Creme but it could also be their thyroid). When T3 is in balance the body can regulate temperature and energy production without problems. Thus it can be extrapolated that long standing steady exercise (floating around that 65-75% VO2max) will generate long periods of increased body core temperatures and energy expenditure raising the watchful eye of the thyroid. If it could talk, the thyroid would be saying, “Hey, what’s going on out there guys ? Why are we cranking up the heat and blowing all these fuel sources, EVERYDAY !? ” And since the thyroid is always on this alert, it is watching for signs it needs to REACT to preserve the organism and its energy stores. So when it see these long periods of increased temperature and energy expenditure it naturally senses that it must intervene to preserve them. Thus, it drops T3 output, temperature drops as well as metabolism. The brain and hormonal regulatory feedback systems decide then that the problem is solved, the organism can survive to live another day.  Unfortunately for the athlete this is not a productive thing when training for a marathon, so they override the signs and symptoms and get back at it tomorrow. Now, in this state, other fuel sources become vulnerable including muscle and bone mass. Plus cortisol ramps up and we all know how destructive long term heightened levels of cortisol can be. Not only are they catabolic in sustained high levels, they alter the adrenal hormonal loops with the brain, sacrificing hormones like DHEA and pregenalone to mention only a few (ie.Pregnenalone Steal Syndrome) and their associated feedback loops.

We see alot of serious athletes with this kind of stuff and sometimes we have to order hormone panels for these problems to see just how messed up the loops are and to determine where to start. Sometimes we just look at them and ask why they think more training trumps rest and recovery.

As a brilliant doctor in these fields said to me the other day while discussing Keifer’s article, “When the HPA axis is activated, the CRH response from the hypothalamus to pituitary begins the upregulation of the adrenal axis and directly inhibits TSH.  And the glucocorticoid response will also inhibit TSH.  If the body is under siege and goes into a catabolic state it should naturally have an inbuilt protective mechanism to slow the rate of breakdown! ” Thank goodness our body has this mechanism !

What did he say ?  In a nutshell, what he said is that the hormonal systems are all connected via feedforward and feedback loops to make sure the body is balanced and healthy.  When the body is working out too much and expending too much energy, heat and breakdown for long periods of time turn on these protective feedback loops in an attempt to protect the body.  The thyroid and adrenals are often at the mercy of the process, as well as your healthy hormone levels, muscle and bone mass (read more on this in Kresser’s short article) as well as energy. 

Staying healthy, it is a fine line.  Don’t forget that rest and recovery are critical for your performance, but more importantly for your health.  A  recovery day should be just that, recovery ! Not an easy 50 mile bike ride !  That is not deemed as recovery to the hormonal regulatory mechanisms of the body.  This stuff bodes us to share the statement……. “more is not always better”.  Don’t forget that your body needs to be fed rest and recovery just as much as good food and sleep. And, do not mistake this article to say that exercise is bad either, we all know the truth there.

There are some really great articles out there that talk about the similar physiologic effects of brief high intensity workouts when compared to sustained steady state exercise.  And, they might help save your body in the process if you are one of the vulnerable ones (and there are alot of vulnerable ones !).

Want to read John Keifer’s orginal article on this, go back up to the link provided at the top of the page. We tried to summarize a very difficult topic (even for some physicians) so don’t feel bad.

Shawn and Ivo

Ya, we are a little more than just Gait Guys. We try to take care of our athletes on every level.  This may  not have been gait related today, but it sure was running related. 

_____________________

Retail Focus Thursday: The Heel Counter/ Heel box

Let’s differentiate between the heel counter and a lateral flare of the out sole.

The heel counter refers to the back part of the upper of a shoe that actually holds the heel in place (see left above).

The lateral flare is part of the outsole, where it is enlarged laterally, to create stability to a shoe. (see right above). It does this at the expense of speeding up pronation (we usually strike on the outside of the heel, creating a greater sidtance to travel in the same amount of time; again, another post for another time). Good idea for one problem, but often creates another.

The heel counter is necessary, because as the foot pronates from its initial contact with the ground through midstance, the calcaneus moves laterally (or as shoe pro’s say “it everts”).  If the calcaneus does not encounter something to abut up against (like the heel counter), to stop rearfoot pronation at the appropriate time, it will continue to evert and the medial arch will collapse.

“So what” you say? Excessive rearfoot motion, like this can not only cause prolonged midfoot pronation (remember it pronates to absorb shock to midstance, then supinates to create a rigid lever to push off of. Click here if you need a pronation review), but is a common cause of heel blisters. How many times do you remove a clients shoe (hopefully you are removing their shoes and looking at their feet before selling them some shoes) and you notice a “bump” (and sometimes a blister) on the back of the heel (see above) and the outer portion of the heel box is worn on the inside of the shoe? Hmm, sounds like too much room in the heel box.

What causes too much room in a heel box? Narrow heels (or calcaneii , as we like to say) or literally, too much room. The “too much room” scenario often happens when you put a woman’s heel (usually narrow) in a men’s shoe (often wide)

A little lost? Have no fear;  the complete shoe fit program (with IFGEC certification if desired) is coming in the next few months. Watch here, on Facebook or Twitter for the announcement.

The Gait Guys…Shoe afficianado’s. Bringing you the facts so you can make better decisions….

heel counter image from: www.hughston.com

The Boston Marathon Black & Bloody Toe nail epidemic. (want the truth, read on)

Just in time for all those black bloody toenails at the Boston Marathon. We are going to try to repost this blog post (last June 2011) every year around the Boston Marathon. We need to kill the myth of “ I lost my toe nails because my shoes were too short”.  How stupid is that theory !

Our next statement is always “well, if you bought shoes that short you deserve it. But we doubt that is the case."  Here is likely why you got a black toenail or lost your nail in the marathon. ”

The Gait Guys have it figured out for you.  This just makes more sense gang. It makes sense because it is the answer.  Click the link below.

http://thegaitguys.tumblr.com/post/6355488304/the-black-plague-ok-kinda-sort-of-subungal

Neuromechanics Weekly

Bad posture is ubiquitous:Our Flexor Driven Society

We know you visit here often and read the blog. You do it because of your desire to learn and possibly because of curiosity and wondering what exactly it is that we are saying, or not believing that we actually said it…and can back it up!  Do you remember that we said most joint and muscle receptor activity goes to the cerebellum? Do you remember that the cerebellum is NECESSARY for learning? Not just motor learning but ALL learning…

Curious? Read on…

If you think the economy is our problem, maybe you need to look a little closer. These  pictures are from a few days ago while at the playground with my kids (yes, the gait cam again…yes, we are watching YOU).

Many human ailments can be linked to imbalance. The Chinese recognized this a few thousand years ago with the concepts of Yin and Yang (pronounced Yin and Yawn; I can still hear Dr Springfield saying “Anyone who says Yang (rhymes with Tang) fails the course). Equal opposing forces are meant to remain in balance to create homeostasis.

This picture is a perfect example of flexor/extensor imbalance (stooped posture creating slow stretch of the extensors of the spine/back and gluteal muscles), which, over time (30 mins or  more) increases muscle length.

We are a flexor driven society. Think about all of the voluntary, fine manipulative movements you can make consciously (buttoning a shirt, typing, pushing off with gait). These are all corticospinal (long neurologic tracts from brain to spine) driven phenomenon (ie under conscious control) which are ultimately driving the flexors (go ahead, try and button your shirt with the backs of your fingers (ie. extensors); if you can do it, please send us the video, so we can post it).

Now think about the activities, like standing upright, that are dependent on our extensors, which are largely under the purview of the vestibulospinal system (driven from the cerebellum and vestibular nucleii in the brainstem). Try and contract your L2-L3 lumbar multifidus on the right: you can’t, because it is not under conscious control.

Let’s extrapolate further…We tend to use that which we can control, thus we use our calves and deep flexors of the posterior compartment of the leg. These cause knee flexion and plantar flexion of the foot (and dorsiflexion of the 1st MTP, provided there is adequate range of motion available), which reduce ankle rocker. They will reciprocally inhibit the anterior compartment muscles (like TA and EDL, EHL). Your center of gravity shifts and now you need to engage the quads to right it, rather than the more efficient gluteals. Now the pelvis tips forward due to action of the rectus femoris, shortening the glutes and putting them at a mechanical disadvantage (in addition to functionally weakening the lower abdominal compartment, making athletes more susceptable to hernias), so now we use the hamstrings (but these are reciprocally inhibited by the quads), so we default to the lumbar erectors and so on up the chain.

Flexor dominance leading to extensor inhibition. Not to mention that the cortico spinal pathway (flexors) inhibits the vestibulo spinal and retculospinal pathways (which both drive the extensors) in the brain stem. So, there is a local, segmental effect and cortical loop. When we continue to utilize certain pathways in the brain, they become ingrained (collateralization and facilitation) and that’s how bad motor patterns begin.

Look at the picture above again. Flexed lumbar and thoracic spines, flexed arms, flexed wrists, flexed hips, flexed knees. Not too much extensor activity going on, eh? Thus, More inhibition of the extensors.

We know you visit here often and read the blog, because of your desire to learn. Do you remember that most joint and muscle receptor activity goes to the cerebellum? Do you remember that the cerebellum is NECESSARY for learning? Not just motor learning but ALL learning…

So, sit up straight. Eat your vegetables and work your extensors. Your intelligence depends on it!

Ivo and Shawn. The Gait Guys. Telling you what you need to hear, but don’t necessarily want to hear. Yes, we are watching and yes, our glutes are engaged.