Welcome to Friday Follies.

Here we see people putting their foot in their mouth….

Have a great day

Ivo and Shawn

The extensor hallucis brevis revisited…or……axes of rotation

In a previous post, we described the attachments and importance of this little, but important muscle. Today we will explore that further.(4 images above, toggle through them)

We recall that the EHB is not only a dorsiflexor of the proximal hallux, but also a descender of the head of the 1st metatarsal . Why is this so important?

The central axis of a joint (sometimes called the instantaneous axis of motion) is the center of movement of that articulation. It is the location where the motion will occur around, much like the center of a wheel, where the axle attaches. In an articulation, it usually involves one bone moving around another. Lets look at an example with a door hinge.

A hinge is similar to a joint, in that it has parts with is joining together (the door and the jamb), with a “joint” in between, The axis of rotation of the hinge is at the pivot rod. When the door, hinge and jamb are all aligned, it functions smoothly. Now imagine that the hinge was attached to the jamb 1/4” off center. What would happen? The hinge would bind and the door would not operate smoothly.

Now let’s think about the 1st metatarsal phalangeal joint. It exists between the head of the 1st metatarsal and the proximal part of the proximal part of the proximal phalanyx. Normally, because the head of the 1st metatarsal is larger than the heads of the lesser ones, the center of the joint is higher (actually,almost 2X as high; 8mm as opposed to 15mm). We also remember that the 1st metatarsal is usually shorter then the 2nd, meaning during a gait cycle, it bears the brunt of the weight and hits the ground earlier than the head of the 2nd.

The head of the 1st metatarsal should slide (or should we say glide?) posteriorly on the sesamoids during dorsiflexion of the hallux at pre swing (toe off). It is able to do this because of the descent of the head of the 1st metatarsal, which causes a dorsal posterior shift of the axis of rotation of the joint. We remember that the head of the 1st descends through the conjoined efforts of supination and the coordinated efforts of the peroneus longus, extensor hallucis brevis, extensor hallucis longus, dorsal and plantar interossei and flexor hallucis brevis (which nicely moves the sesamoids and keeps the process gong smoothly).

Suffice it to say, if things go awry, the axis does not shift, the sesamoids do not move, and the phalanyx crashes into the 1st metatarsal, causing pain and if it continues, a nice spur you can write home about.

Ivo and Shawn….Still Bald…Still good looking…still promoting foot literacy everywhere

Gait / Running: Problems with Big toe pain or power ? The Big toe in motion: another look at a past video we did on EHB and impact on the big toe ! Enjoy this blast from our recent past……. 2.5 years ago……  this video is worth your 5 minutes if you want to get smarter at this stuff !

enjoy…….. Shawn and Ivo

Gait Topic: The Mighty EHB (The Short extensor of the big toe, do not dismiss it !)

Look at this beautiful muscle in a foot that has not yet been exposed to hard planar surfaces and shoes that limit or alter motion! (2 pics above, toggle back and forth)

The Extensor Hallicus Brevis, or EHB as we fondly call it (beautifully pictured above causing the  extension (dorsiflexion) of the child’s proximal big toe) is an important muscle for descending the distal aspect of the 1st ray complex (1st metatarsal and medial cunieform) as well as extending the 1st metatarsophalangeal joint. It is in part responsible for affixing the medial tripod of the foot to the ground.  Its motion is generally triplanar, with the position being 45 degrees from the saggital (midline) plane and 45 degrees from the frontal (coronal) plane, angled medially, which places it almost parallel with the transverse plane. With pronation, it is believed to favor adduction (reference). Did you ever watch our video from 2 years ago ? If not, here it is, you will see good EHB demo and function in this video. click here

It arises from the anterior calcaneus and inserts on the dorsal aspect of the proximal phalynx. It is that quarter dollar sized fleshy protruding, mass on the lateral aspect of the dorsal foot.  The EHB is the upper part of that mass. It is innervated by the lateral portion of one of the terminal branches of the deep peronel nerve (S1, S2), which happens to be the same as the extensor digitorum brevis (EDB), which is why some sources believe it is actually the medial part of that muscle. It appears to fire from loading response to nearly toe off, just like the EDB; another reason it may phylogenetically represent an extension of the same muscle.

*The EDB and EHB are quite frequently damaged during inversion sprains but few seem to ever look to assess it, largely out of ignorance. We had a young runner this past year who had clearly torn just the EHB and could not engage it at all. He was being treated for lateral ankle ligament injury when clearly the problem was the EHB, the lateral ligamentous system had healed fine and this residual was his chief problem.  Thankfully we got the case on film so we will present this one soon for you !  In chronic cases we have been known to take xrays on a non-standard tangential view (local radiographic clinics hate us, but learn alot from our creativity) to demonstrate small bony avulsion fragments proving its damage in unresolving chronic ankle sprains not to mention small myositis ossificans deposits within the muscle mass proper.

Because the tendon travels behind the axis of rotation of the 1st metatarsal phalangeal joint, in addition to providing extension of the proximal phalynx of the hallux (as seen in the child above), it can also provide a downward moment on the distal 1st metatarsal (when properly coupled to and temporally sequenced with the flexor hallicus brevis and longus), assisting in formation of the foot tripod we have all come to love (the head of the 1st met, the head of the 5th met and the calcaneus).

Wow, all that from a little muscle on the dorsum of the foot.

The Gait Guys. Definitive Foot Geeks. We are the kind of people your podiatrist warned you about…

This week for neuromechanics, something a little different. A fun video by Mark Gungor about the differences between male and female brains. Sit back, relax and prepare to laugh!

Of interesting historical note; he describes the differences between the male and female brains perfectly as the contrast to early neuronal theory out forth by Ramon Satiago Cajal: Prior to the 1800’s it was thought the nervous system was continuous (much like the female brain wiring) however he (Ramon) proved it was contiguous (ie. there were synapses).

The Gait Guys….Thinking outside the box, even though we have a special “gait box” in our brains.

Ivo and Shawn

We’ve got an angle….. The Progression Angle

1st of a non sequential series

The progression angle is the angle to foot makes with the ground at initial contact of gait to loading response, and it is often carried through the gait cycle to toe off (see left image above). It is something we often look at to see how a patient may be compensating. It often represents how forces are traveling through the foot (see right image above).

The normal line of force through the foot during a gait cycle should begin at the lateral aspect of the heel, travel up the lateral column of the foot, across the metatarsal heads from the 5th to the 1st, and then through the hallux (see L part of right picture above.

We remember that the foot strikes the ground in a supinated posture, then pronates from initial contact through the middle of midstance (to provide shock absorption and initiate medial spin of the lower extremity: see picture bottom left); the foot should then supinate, to make the foot into a rigid lever, with this being initiated by the opposite limb going into swing and externally rotating the stance phase lower extremity (se picture bottom right)

The progression angle is determined by many factors, both anatomical and functional, and is often a blend of the 2.

Anatomical factors include:

• subtalar joint positioning
• tibial torsion
• femoral torsion
• acetabular dysplasia

and functional causes can include:

• compensation for a hallux limitus or rigidus
• weak glutes (of course we wouldn’t leave our favorite muscle out)
• loss of ankle rocker
• over or under pronation
• and the list goes on….

Next time we begin breaking this down into bite sized chunks to aid digestion.

Ivo and Shawn. Bald. Good Looking. Middle Aged. Definitive Foot and Gait Geeks : )

The Gluteus Maximus: Part 2. More talk on gluteal function & its place in the gait and running cycle.

The gluteus maximus controls:

Flexion / Extension: The Sagittal Plane
- the rate and extent of limb flexion at term swing: this is eccentrically controlled
- hip extension: this is concentrically controlled
- hip flexion rate during loading response (eccentric at foot loading): this will help to control the vertical loading response as the body mass loads the limb there must be enough eccentric strength of the glute maximus to control-stop this loading so that hip extension can occur. This will indirectly assist in control some of knee flexion.

Rotation:
- external rotation of the limb: this is concentrically controlled
- assists in controlling the rate of internal rotation: this is eccentrically controlled

Pelvic Posturing:

- controls rate of Anterior Pelvic Tilt (APT): this is eccentrically controlled (this is relative hip extension as discussed in Part 1 last week)

- assists in Posterior Pelvic Tilt (PPT): this is concentrically driven

- controls sacroiliac joint mobility through FORCE CLOSURE (force closure is a compression of the joint surfaces by the contraction of muscles that cross the joint)

Divisions:

- the sacral division of the gluteus maximus is mostly a pure sagittal plane driver at the hip joint
- the coccygeal division is more of an adductor and internal rotator at the hip joint
- the iliac division is more of an abductor and external rotator at the hip joint

The gluteus maximus also has some fascial attachments into the posterior aspect of the TFL-ITBand. Remember, this TFL-ITB complex is an internal rotator of the limb in the gait cycle. You will recall that internal rotation is a precursor to hip extension. The hip must first, and adequately, internally rotate in the gait cycle before hip extension can occur. This means that for correct and complete gluteus maximus contraction to occur in the second half of the stance phase we must have adequate internal hip rotation. Without it, all of the things we talked about last week in our glut maximus blog post cannot occur properly. Now, back to our attachment disucssion of the gluteus maximus to the ITB-TFL mechanism. This attachment allows the gluteus maximus to produce posterior tension on the ITB-TFL mechanism so that it can be anchored to provide it’s internal rotation function on the limb. So, here we have a powerful hip extensor and external rotator providing assisted effects on an internal rotator of the limb. Isn’t the body a beautiful and amazing thing ! (Well it is. But if you will recall from the detailed layout above that the gluteus maximus in the eccentric phase of contraction functions to control the rate of internal hip rotation you will not be surprised or enlightened. Rather you will enjoy the brilliance of how an anchoring muscle is eccentrically giving up length while an agonist muscle is concentrically taking up length). The gluteus maximus-TFL relationship….. it is beautiful teamwork in helping, not exclusively of course, control limb rotation during loading responses.

Next time you see a client’s knee drift too far inwards during a lunge, or walking or running we hope this whole discussion will spring a light bulb moment for you. You must look at the complex function above in controlling the limb during pronation and supination. Merely inserting an orthotic is not going to fix a proximal deficiency, it could modulate it however. But wouldn’t you want to fix it ? Who wants an orthotic if you don’t need one ? Some people do, don’t get us wrong, but many do not. And then some just need them temporarily to gain the awareness and skill of posturing and function and once that is achieved the device and be weaned.

Just some more functional anatomy talk on a Monday morning…….from us, The Gait Guys

Shawn & Ivo

Gait and Foot pain in a 30 year runner. A possible Forefoot varus.

Hi Gait Guys:

I could use some help. I’ve been running/cycling for 30 years. Three years ago, I had surgery on my left knee that realigned my patella (lateral release.) Until recently, I lived in custom orthotics and motion control shoes. I’ve been reading chi-running and natural running and bought a pair of shoes for which I’m transitioning a little a day. My left foot is the problem: it severly overpronates and I have a neuroma. I’ve been walking barefoot and in five-fingers for a while and my feet a definitely getting much better. The natural running style feels much better on my ankles,knees and hips, which used to hurt a lot. Also, cycling hurts only when I get off my bike, my knee is killing me for a while.

My left forefront seems to move too much even with this new style of walking/running. I’m wondering if I have forefront varus that could be helped with a wedge. My real problem is that I currently live in Las Cruces, NM, where there is no running store and no experts on this stuff. Most podiatrists do the same, generic thing for all patients. Is there a little wedge I could try without having it inserted into a custom orthotic? Is there a place to go to analyze my gait/running that would be worth my time and expense to visit? Any advice would be gratefully received.

Thanks for your time, …. AT

_____________________________________

Thanks for the note AT.

We are glad that the natural style running is helping. remember to go slowly and follow the rules of Skill, Endurance, Strength as you progress into less supportive shoes.

The forefoot motion you are sensing MAY indeed be a forefoot varus; we would need to see and examine your foot to know for sure. The fact that you have had a neuroma and needed a lateral release are suspect for a forefoot varus.  With that 1st metatarsal head (the medial tripod) unstable and allowing more forefoot pronation your control of internal rotation of that limb is going to be difficult and drag patellar tracking off line. If it is a rigid deformity, it may never totally be gone, though you may be able to increase the range of motion of your foot sufficiently to compensate elsewhere. We have attached a photo of a prefabricated forefoot varus post (note its thickness on the outside edge and tapering as it moves inwards to the pre-fab it is attached to. It is a wedge.). In our in-house labs we make them custom to the client to get perfect control. We make them out of thermo-rubber-infused cork so we can grind them down as clients earn better ability to anchor the metatarsal tripod with intrinsic muscle strength through our specific exercise programs. It is also used for Rothbart Foot types which has some similarities to a forefoot varus. Make sure you do not have a Rothbart variant. We did a blog post on Rothbart many years ago. Search for in the search box from our archives.

Getting a thorough evaluation is paramount. We are not aware of any gait labs in Las Cruces, but Jaqueline Perry’s Pathokinesiology lab is in Rancho Los Amigos (click here for more info). Dr Waerlop is located about 70 miles west of Denver and Dr Allen is in the Chicago suburbs. Only after an evaluation, could exercise suggestions or an orthotic or other device recommendation could be made.

Thanks for your inquiry

Ivo and Shawn

Redoing your gait analysis?

Gait Guys:

How often do you need to get a gait analysis done when buying new runners? Started running one year ago and bought my first “real” pair of runners last spring. I have a ‘neutral’ foot or gait. Do I need to get it done now again when buying new ones or should I just go with the neutral runner gain? Does it change much over time with all that mileage?

Name Removed

Our Response:
Your running style will evolve (for better or worse) as you evolve as a runner. If you have had an adequate gait analysis initially, you should probably have a new one done every 6-12 months, depending on your training (style and mileage) and what your ultimate goals may be, especially if you are working at improving your running gait (which we hope you are!).

Ivo and Shawn

READY

Great Gait: You don’t see this that often

Great gait brought to our attention by one our readers; one his questions was how he had such great “kick back” traveling at the speed he was traveling at. 

 

Here is an efficient gait:  note he mid foot strikes (you may need to watch it a few times to see it) close to under body and does not over stride; he has great hip extension, and a forward lean at the ankles; even arm swing (note elbows do not go forward of and wrists do not go behind body). It all adds up!

So what causes such great hip extension? Largely 2 factors: forward momentum and glute (all 3; max, med and min) activation. From the last post and EMG studies, we know the glute max contracts at initial contact (foot stance) through loading response (beginning of mid support) and then again at toe off to give a last “burst”; the gluteus medius and minimus contract during most of stance phase. initially to initiate internal rotation of the femur (a requisite for hip extension);  the former to keep the pelvis level and assist in extension and external rotation during the last half of stance phase to assist in supination and creating a rigid lever to push off of. This is, of course, assisted by the opposite leg in swing phase.

Forward lean and momentum move the axis of rotation of the hip behind the center of gravity, assisting the glute max to extend and prepare the lower limb for the bust at push off. The stance limb, now in external rotation, makes it easier to access the sacral (especially) and iliac fibers of the glute max and the posterior fibers of the gluteus medius.

What a orchestration of biomechanics resulting here, in a symphony of beautiful movement.

The Gait Guys. Bringing you great gait, when available…..

A little something for our triathletes today on Friday Follies.

:-)

S & I (thx Les)

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Gait: When is the last time you used the swear words “closed kinetic chain” ? How well do you understand your Gluteus Maximus ?

These are just some fragmented, early morning, mental ramblings about the genius of the body. We are sure to follow up with more glute talk in time.

When the foot is engaged with the ground one of the major functions of the gluteus maximus is to draw the pelvis into posterior rotation (with some assistance of some other regional muscles of course). The pelvis is extending on the femur through the hip joint axis. If the foot is off the ground one would call this hip extension. But when the foot is on the ground, it is still hip extension, however our mental reference must change. This motion we have described, when the foot has purchase on the ground, is what happens when we return upwards from a squatted position (see ! it is still hip extension). You may find it a brain twister to look at the qluteus maximus also as a rotator of the pelvis away from your foot progression direction. Meaning, we think of the gluteus maximus also as an external rotation generator but when the foot is ground engaged contraction of the G. Max spins our pelvis (and connected torso) away.

Go ahead, stand on your right foot and contract your glute maximus. Which way does your body rotate ?

So, when contracted, if the right foot is on the ground the body pelvis-torso will spin to the left.

So, how do we use our glutes to help us move forward ?

Well, this is a complicated chain of events and this was not the purpose of our ramblings today. This muscle does not work in isolation. Might we just say that there is an opposite swing leg moving forward into flexion which helps to redirect that spin into a sagital progression. Go ahead, stand on that right foot again, contract the glute maximus and note the left rotation, but now add the left forward hip flexion placing the left foot into forward progression. Do you feel that torque and compression through the right hip, core and spine ? Do you have enough core strength to not prostitute the pelvic neutral posturing ? Did you drop into an anterior pelvis tilt (APT) ? Go ahead now, add the anti-phasic motion of contralateral arm swing just to add some more complex rotation to the picture. Are bells and whistles going off about some of your clients problems ? You might want to go back and re-read our work on Arm-Leg swing now. (click here). We plan to build on these concepts in the very near future ….. keep up with us, be ready !

There was alot going on here in what we just did. More on this another day, time to go put this gait stuff to our Friday patients. That is right, we just don’t talk about this stuff, we live it. Remember, unless your patients, clients and athletes wheeled themselves into your facility …… they walked in via the gait cycle. Know your stuff.

Have a great weekend peeps

Shawn & Ivo

“Learn a clean motor skill slowly, add endurance to that slow clean skill, add strength to that skill. Rinse and repeat.
Layering progressive skills and eventual speed to the prior skill achievements … until, like any high end movement endeavor, the task is unconsciously competent. Skipping any step in this logical neurophysiologically based ladder will result in a compensation pattern.”

—

The Gait Guys

Shawn & Ivo

“Form is dictated by Function.”

—

Excerpts from, “Building the Elite Efficient Injury free Athlete”. The topic at this years ITCCCA lecture.

It’s been said “Form follows Function” , to be clear……Form is dictated by Function.

For example, If you do not have good ankle rocker function your Form will:

1- not be optimal
2- require compensation / cheating
3- change, be limited, and prevent desirable Form
(Inefficiency + increased workload = eventual injury or system failure)

Your Form can only be as good as the Functioning of your physical parts.
If you or your athlete has bad Form….. Spending weeks on “running FORM clinics” or training hard to improve a loss of Form may only force new compensations. The solution to better “Form” is often sitting right in front of you in the form of biomechanical dysfunction. When you see bad Form you should ask yourself if that person lacks the functional parts to give you good Form. What you see in someone’s Form are their capabilities with the parts they have that work.

Mind you, some athletes or patients have all normal functioning parts available to them and all they need is Skill coaching or first level skill rehabilitation exercises … the first part of S.E.S. (*Skill, Endurance, Strength). Just always be on the look out for bad function.

Said another way, forcing what you think is good Form will quite often not work on someone with limitations; It will only develop further strength into a compensation pattern that you do not want. Instead, do the necessary initial work to resolve the function limitation so that you can begin to engrain skill Form patterns.

An elite and efficient athlete is one who:
1- has the parts ( sport is matched for body type),
2- presents with no dysfunction … . thus clean FORM,
3- understands that “more is not always better”
4- and has a coach, trainer or medical professional that can teach progressing levels of S.E.S. into that individual.

From this years lecture on “Building the Elite Efficient Injury free Athlete” presented January 14th at the ITCCCA (Illinois Track & Cross Country Coaches Association. This was a standing room only event. We look forward to presenting what we learn in 2012 at next years event. Thanks to all those who endured 2 hours sitting in the stairwells, on the floors and in the seats. Good luck this season everyone !

Shawn, Ivo & Coach Chris Korfist

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Educate yourself here (click). SOPA PIPA

Watch this girl walk. What is the most striking feature of her gait?

Is it the genu valgus? Is it her progression angle (or lack of?) Her Left sided increased arm swing? Her body shift to the left in Left stance phase?

We would like to discuss her progression angle. We remember that the progression angle is the angle the foot makes with the ground at heel strike and through stance phase (another way of describing it is, Are your feet turned out or turned in?). It is determined by many factors (forefoot position, subtalar joint angle, tibial abnormalities, femoral torsions, etc). In this case it is highly suspect that it is due to subtalar varum and internal tibial torsion, at least from what we can see and what we now without the advantages of an exam and clinical information.  Lets now make this assumption and talk about it from this angle.

Tibial torsion is due to the development of the tibial shaft. It begins in utero, where most of us have tibial varum (due to intrauterine positioning), usually Left sided more than right (because most babies are carried on their back on the Left side of the mother and the Left leg overlies the Right in an externally rotated and abducted position.

At birth, we usually have a 5 degree toe in due to a 30 degree angle between the talar dome and head, which slowly decreases to approximately 18 degrees as we grow into adulthood, leaving us with a 4 degree toe out (still a fairly narrow progression angle). Meanwhile, the tibial plateau and malleoli are parallel at birth and the distal tibia “untwists” externally as we age (at a rate of about 1-1.5 degrees per year) till it reaches an ideal of 22 degrees in adulthood.

Over rotation of the distal tibia (relative to the proximal) results in external tibial torsion with a “toe out” or as it is referred to as, increased progression angle. Under rotation results in internal tibial torsion, or a “toe in”, also referred to as a decreased progression angle.

Some sources say that the development of the talus (angle between the dome and head) is largely responsible for foot position and progression angle. We think that careful measurement (looking at the transmalleolar angle, a topic for another post) reveals which it is, and in our experience, it is usually a combination of both (ie tibial torsion and talar development).

This video is an excellent clinical example of an in toed gait, a negative progression angle.

Ivo and Shawn…The Gait Guys….Yes, we are torsioned (or twisted as some may argue)….straightening out the facts so you don’t have to.

More constructive dialogue on The Cross Over Gait: Q & A Session with a Mid-Distance Coach.

Dear Dr. Allen,

I attended your sessions yesterday at the ITCCCA Clinic, which I appreciated very much.  I am a retired middle/long distance runner who is now getting into coaching.  I have always been fascinated by this kind of research and spotting warnings [things presented at the conference this year ] before they become injuries.  I think that the attention you are bringing to video analysis, form, and SES is the most significant change happening in the sport of running.  Applying this analysis to young runners will help countless numbers of them, both by identifying weaknesses to strengthen and by alerting coaches to an athlete’s propensity for certain overuse injuries. 

As your work gains much deserved attention, I do have a concern with your approach to the “cross-over gait."  I spoke with you briefly about it yesterday, and I have been thinking about it since then.  From my experience and amateur research, it seems as though a distance runner does well to strike both feet along a single line.  Here is a little of my reasoning:

Distance running is largely about efficiency.  While a sprinter gets more power and speed by pushing in a zig zag pattern from foot to foot, that does not mean it is an efficient action.  A distance runner does want some power in his/her stride, but cannot afford to waste any energy like a sprinter can.  I would argue that the difference between a sprinter’s ideal stride and a distance runner’s ideal stride should reflect this. 

It seems logical that a runner’s most efficient push-off point is directly beneath his/her center of gravity.  If we strike the ground to the left or right of this point, some energy goes into sideways motion or adjusting for the asymmetrical force with more glute action.  To your point, this off-center stepping pattern almost certainly yields more power than a straight-line pattern, as the best short-sprinters all use it.  I found this video of Carl Lewis’ beautiful stride demonstrating your point.

However, if you look at the best distance runners in the world, and even middle distance runners, you’ll see much more "cross-over."  The other two videos I list below aren’t great, because they’re in real time, but you can still discern the in-line foot strike of most of the athletes.  These runners may be getting less power out of their glutes, but they’re taking advantage of the gluteus maximus’ natural design to rotate the pelvis forward efficiently.  For most of the race, I’m not convinced that altering that pattern would be productive.
 
I am far less knowledgeable than you in physiology and biomechanics, and I have not performed the necessary research to substantively contradict you, but I write to request that you investigate this issue further.  I may also have misunderstood the nature of your form adjustment work with middle- and long-distance runners; kicking at the end of the race or surging in the middle could very well take more of a sprinter’s form.  The general stride of a distance runner, however, is likely specific to the particular demands of the race and the body’s aerobic limitations. 

I think that coaches should be very careful to adjust a runner’s natural stride unless there is significant evidence supporting the change.  When the evidence is clear, I like that your approach is as deep as possible: finding the root cause of the weakness and working on it gradually.  I fully support your efforts to prevent injuries in this way.  I urge you to continue expanding the body of research and striving to improve the experiences of budding runners.

Thank you for considering my observations.  Please feel free to contact me anytime.

A.

______________________________

Our response:

Dear A.:

I appreciate your inquiry in the most cordial manner, the coaching world is blessed to have attentive and curious coaches like yourself. Great insight comes from great questions like this. 
I certainly do appreciate your concerns.  But your personal opinion needs some backing. I fully respect and understand your thoughts and although they are well thought out, there is nothing i have found in the literature to support it.  Mind you, there is not alot to support mine either however results do have a voice and when we make these changes, even in our mid distance runners, their injuries resolve and do not recur and their times drop.  So, there is some strength to the crossover correction it seems. More research would be nice but no one is doing it so we must base our thinking on some logic as laid out below.

Keep in mind efficiency comes with using each muscle optimally and quite often in
"line running” (crossing over) the gluteus medius and foot do not work correctly. Look at the terrible foot function in the video above. Please watch and read our 2 part series on the blog on Lauren Fleshman(links below). She is fraught with injuries and her hip and foot biomechanics are terrible as we point out in both of those blog posts.  Improving her muscle efficency in using them correctly will improve her overall kinetic chain efficiency, certainly make her less injury prone, and probably make her faster. 
As for putting one’s foot under their body mass,  I challenge your thought merely because when you are on one foot your center of mass is shifted over to the stance leg not directly under your sacrum (watch my 2 part series on youtube “hip biomechanics”,  here I explain the accepted biophysics of the kinetic limb).
The foot should be under the knee and hip, where the body mass has shifted in the single leg position.  The only person who will not shift their mass is one who doesn’t use their gluteus medius to draw the mass over the hip (again, it is in the hip mechanics videos) and that person will likely have hip problems in time because the compressive load on the femoral head is excessively abnormal plus they are often fraught with trochanteric bursitis and chronic ITB issues (let alone knee and foot issues).

Please digest what I have said here and lets keep a constructive and productive dialogue going, nothing I said here was meant to upset you, merely to try to give you my stance.
I am never afraid to have my theories challenged. I am humble enough to know I do not know everything and admit when I am wrong. I want to learn and get smarter so I can help more athletes and coaches become better.  So, if you can refute my dialogue above, particularly with science and research, I am happy to continue this learning experience for us both.  But please watch the videos I have mentioned first so we can base our discussions on solid functional anatomy and biomechanics (save us time, so we can get down to a good dialogue).
So, to this point, although i see your logic, I respectfully must disagree from sheer fact on anatomy, physics of body mass shift, and biomechanics.  I think you will find the 2 brief lectures on hip biomechanics exciting and helpful.
Remember, the swing leg is a pendulum, the most effective pendulum is one that never shifts its center of pivot (energy change),  the cross over gait shifts with every step. A centrated joint is one that pivots freely allowing the attached musculature to function as they were designed.
 I look forward to future constructive dialogue. I would like our relationship to be an asset for us both.

Below are the videos, in logical order, to support my response.

http://thegaitguys.tumblr.com/post/10239421449/dr-shawn-allen-discusses-gait-biomechanics-again

http://thegaitguys.tumblr.com/post/10400372557/in-this-part-2-installment-of-applied-hip-gait

http://thegaitguys.tumblr.com/post/13158702554/the-cross-over-gait-in-a-professional-runner

http://thegaitguys.tumblr.com/post/13298030775/how-a-really-fast-runner-could-potentially-be

http://thegaitguys.tumblr.com/post/13205227823/gait-video-analysis-olympian-carl-lewis-carl

Then of course there is the 3 part crossover gait series we did on August 24th & 25th (you can access our archives by clicking on the clock in the upper right corner of the blog page).

respectfully……. and fully appreciating your passion
shawn and ivo……. The Gait Guys

Foot Strength: Some Clinical Q & A.→

A Few question (and answers) about Foot Problems, from our Blog.

Dr. Ivo Waerlop and Dr. Shawn Allen,

I have had the pleasure of reading much of the content of your website and I have gained many valuable insights into the fascinating world of gait. I have a number of questions that I would love to get your perspective on though. First question: What exercises or techniques do you use to strengthen the intrinsic foot musculature? I gleaned that you are not particularly fond of flexor dominant exercises like towel scrunches so how do you functionally improve the strength, muscular balance and neuromuscular control over those little muscles? Second question: What strategies do you use when treating runners with plantar fasciitis? Would you move them into a less supportive or minimalist shoe or would you bump them up temporarily into a stiffer shoe or use a rigid orthotic?

I would like to also take the time to thank you guys for posting volumes of valuable information on your website. I have found that your website has a remarkable amount of solid, scientifically based information on topics that typically are rife with misinformation when discussed on other websites. Keep up the excellent work and I greatly look forwards to hearing your response to my questions.

Thanks,

JD

____________________

The Gait Guys Response:

JD:

Thanks for the support and the kudos. In answer to your inquiries:

“First question: What exercises or techniques do you use to strengthen the intrinsic foot musculature? I gleaned that you are not particularly fond of flexor dominant exercises like towel scrunches so how do you functionally improve the strength, muscular balance and neuromuscular control over those little muscles?”

Exercises are prescribed very specific to muscle weakness. There are no “swiss army knife” exercises. Each case is on an individual basis, based on physical exam and muscle testing. For the most part, there are really no bad exercises just bad choices for a specific case and poor execution (although one can easily find on YouTube a plethora of ridiculous examples of foolishness worthy of only The Darwin Award).

The small, intrinsic muscles of the foot have many functions, but flexion of the distal toes is not one of them (this is all afforded via the long flexors, FDL). Proprioception from the feet is very important and information from these muscles, as well as the articulations they traverse, provide the brain with much information about the environment, as well as the landscape they are traversing. Increasing proprioception from the feet (through gradual introduction of more minimalistic footwear and going barefoot) is as paramount, if not more important, as increasing strength. Skill, endurance, strength (S.E.S.) in that order (larger diameter, medium diameter and smaller diameter neurons respectively) is the rule for progressing exercise.    S.E.S. is an abbreviation we coined, but it is based purely on neurophysiology principles …  all of our information is science based. You will find no ‘internet forum’ assumptions here, as  you have so accurately gleaned. As for an example of some of our exercises, we are currently trying to find time to create some new videos of our current exercise protocols. As we mentioned however, it is a difficult projected since each case has different needs and differing orders of protocol. None the less, here is an “oldie but a goodie” from two years ago. Click here.

“Second question: What strategies do you use when treating runners with plantar fasciitis? Would you move them into a less supportive or minimalist shoe or would you bump them up temporarily into a stiffer shoe or use a rigid orthotic?”

A: The causes of plantar fascitis are multifactorial, but I think we all agree that overpronation of the rearfoot, midfoot, forefoot (or a combination) all play a frequent role. Following that assumption as a possible cause, the question is, What is causing the overpronation? Is it due to muscular incompetence? Is it due to loss of ankle rocker? Is it due to a loss of hip extension? Is it due to….. (fill in the blank).

The treatment depends on the etiology. As we just eluded, the cause is not always a foot issue, there can be top-down kinetic chain causes. Progressing them to more minimalistic footwear is a great idea (provided they have earned their right to be in it and have muscular competency and appropriate foot structure). The problem is that not everyone does have the necessary structure to drop into minimalism, some never and some need help with a logical progression.  Modalities like acupuncture, ultrasound and EMS, to reduce inflammation certainly help in pain management and can expedite the healing process. At times, if the case calls for it, using an orthotic to temporarily give them the mechanics they do not have, and relieve some of the tension of the fascia is appropriate. Sometimes the orthotic makes things worse (too much support, not enough support). Sometimes, albeit rare, the orthotic is suspect as the causal mechanism.  The root cause needs to be identified and then the appropriate therapy can be initiated.

We get questions like these all the time. They are great questions but they are often fraught with so many open ended subsequent questions and parameters that we often feel our answers are never good enough.  But, if solving things like plantar fascitis were easy in every case, we would not see clients in our practices who arrive with a bag of orthotics, a long  history of therapy, and multiple failed interventions. There are no easy answers or magic bullets. If there were, there would be no need for The Gait Guys.

Providing answers to difficult questions.

Ivo and Shawn

Robotic Gait Retraining→

People who have had a stroke and have difficulty walking often develop improved gaits when they add robotic assistance systems to conventional rehabilitation. A study funded by the Italian Ministry of Health and Santa Lucia Foundation compared the walks of 48 severely impaired stroke survivors. Half the group received conventional rehabilitation and the other half received conventional rehab plus robotic gait training. The study, published in Stroke: Journal of the American Heart Association, showed the added robotic gait training worked for people with severe impairments, but did not significantly help patients with higher mobility.

The robotic devices are electromechanical platforms attached to a patient’s feet. A physical therapist sets progressive bearing weights and walking paces and measures how the patient is doing.

So, the question is WHY? The simple answer is that we are much smarter than a computer or device. The brain makes millions of calculations per second to perform the concert we call gait. A computer cannot approximate all the variables; only the ones that are programmed. The folks with more mobility (less morbidity) were “smarter” and more than likely, the computer slowed them down. The less fortunate ones needed more help.

The Gait Guys: sifting through the literature and bringing you the highlights.