Forefoot Varus Predicts Subtalar Hyperpronation

Simon,

Thousands of functional foot orthoses are manufactured in the U.S. every day. And every singe one of those devices must have the cast of the foot (or the digital scan) oriented in the frontal plane during the manufacturing process. Heel position is the primary method that is used to determine the frontal plane orientation of the positive cast and the heel is referenced in relationship to the ground. Given the number of functional orthoses that are manufactured annually throughout the world, I would say that heel position/bisection is a very import and clinically useful reference. The issue is to me is not whether you agree with the technique, it is whether you are willing to acknowledge its widespread application daily by thousands of practitioners and orthotic laboratories.

When we manufacture a foot orthosis, it is irrelevant if the cast is adducted or abducted on the supporting surface as this has no influence on the shape of the device. The contact points beneath the met heads and the heel will rest on the supporting surface, so we do not plantarflex or dorsiflex the cast. The only plane we use to orient the cast when manufacturing a functional orthosis is the frontal plane. The frontal plane orientation of the cast has a profound influence on the shape of the resulting device and on the tolerance and function of the orthosis. When it comes to manufacturing functional foot orthoses, the frontal plane is the most important plane of reference (note that the sagittal plane can be altered with heel lifts on the shell). The only other way I know of to intentionally orient the cast in the frontal plane would be to use the plane of the forefoot to the ground. Being that the forefoot is frequently convex, this creates some subjectivity that must be acknowledged. If we were to abandon the heel bisection as a reference in the manufacture of functional orthoses, I can't imagine what we would use to replace it. Anyone who doesn't appreciate how the frontal plane orientation of the cast influences the shape of the finished orthosis, probably doesn't understand the manufacturing technique well enough. Rather than use random placement of the heel, we and most commercial labs use the heel (bisection) as a reference.

Jeff

 

And there you are looking through your father's lens again, Jeff. Can't you see the logical fallacies here? As I said:

A quick critique:
1) It doesn't matter how many devices are made in the US or anywhere else in the world using your fathers method.
2) Saying that the cast MUST be orientated in the frontal plane doesn't make this a true nor valid statement unless you are manufacturing foot orthoses using your father's method.

End of story. You see the issue here? It's all about your father's method, Jeff. When we step outside of that, your arguments become irrelevant.

Answer me this simple question with a yes or no answer: drum roll......... are you ready?.......

Do prefabricated foot orthoses work?

Yes, that's right, they do. There has been no casting, nor orietnation in the frontal plane, nor heel bisection but.... they work, whether the heel was bisected or not. What about all those custom foot orthoses that are being prescribed and manufactured in central Europe where no heel bisection is employed? I guess none of those are working.

 

It isn't a yes or no question. The only correct answer is sometimes!

 

Simon,

You talk like tissue stress and subtalar neutral are clearly defined theories. They are not. There is no such thing as "subtalar neutral theory". These are just terms that some people have used in an unsuccessful attempt to create meaningful labels. Root's work is based on many different theories. To lump them into one and call it Root theory or neutral position theory is wrong. If you read Root, Orien, and Weeds's Normal and Abnormal Function of the Foot, you will find sections that represent "tissue stress theory". Does that mean that they invented the theory? No, it simply means that they described things in a way that sound familiar to those who advocate such a theory. Can "Tissue Stress Theorists" be separated from Root "structuralists"? No, because neither can exist with out the other. For example, on page 76 of Normal and Abnormal, there is a simple drawing of the talus, navicular and 1st met. The caption says "If forces acting upon the talus and navicular bones were theoretically equal and opposite, no tension forces would develop, and no ligaments or muscles would be necessary to maintain stability of the talonavicular joint in this plane (note by Jeff: arrows in picture show pure compression force). Such a theoretical condition does not exist at any joint of the foot".

On page 78 are two drawings of the osseous components of the foot looking down from above the foot. Figure 2-7: "In a foot that supinates normally during propulsion, the interaction of forces at the joints of the medial arch produces small tension forces that can be easily resisted by normal ligament and muscle function. Weight bearing forces (arrow A-B) (note by Jeff: arrow goes from talus to 1st met head) angle very slightly with the ground reaction forces (arrow D-C) in the transverse plane of the foot". In figure 2-8: "When a foot abnormally pronates during the propulsion, the talus is adducted excessively. Weight bearing forces (arrow A-B) angle greatly with ground reaction forces (arrow D-C). Muscles and ligaments must overwork to resist large tension forces that can disrupt the integrity of the bones in the medial arch". Line A-B in the second illustration looks just like a medially deviated STJ axis where as in the first drawing it looks more "normal.

On page 105 it says "Most symptomatology and trauma to the foot is occasioned by instability of the foot that primarily develops during kinetic function. Therefore, the foot should be clinically evaluated, and treatment considerations should be based primarily upon kinetic requirements of the foot. Treatment based upon static considerations has usually failed to provide more than partial relief of symptoms and that relief may only be temporary".

I don't think Merton Root could have been any clearer than he was in that last paragraph! Yes, he use static methods of evaluation BUT, only in addition to muscle testing, gait analysis, stance based measurements and radiographic evaluation of the foot (yes, they routinely took X-rays in those days so they could see the osseous relationship).

Personally I think the effort to promote poorly labeled theories is a waste of time and energy. The primary reasons that I don't normally participate in the Podiatry Arena anymore is because Root's theories and practices are so poorly understood and I am left with the conclusion that the best option to opt out rather than try in vein to clarify them.

My life and career is mostly behind me. I will leave it up to the new generation of leaders in biomechanics and the profession of podiatry to define that path ahead. So far here in the U.S., they are not demonstrating any real inertia for change nor are they making the application of prescription foot orthotic therapy more scientific, practical or accepted. We shall see what the future brings.

Jeff

 

Actually I've told two different stories. The first was an interdepartmental study done by Chris Smith. He put tape over the posterior aspect of the heel and had each member of the biomechanics department bisect the heel and then he measured maximally pronated position and maximally supinated position relative to the leg. As I recall, he noted the range of motion was consistent, but there was a 5 degree range that could be explained by variation of the calcaneal bisection across the members of the department.

The second story did occur at a Weed seminar. I told the participants to use the heel bisection that I gave them and to measure this one person's foot. There was a 10 degree range in the value of forefoot to rearfoot relationship. I kept trying to get the participants to do the measurement independently of each other. They kept wanting to compare notes with the other participants to see if they got the measurement right. These were practicing doctors who did not have confidence in their ability to make an accurate forefoot to rearfoot measurement. I don't think it was a problem with their ability, but a problem with being able to repeat the measurement.

Eric

 

Eric,

What measuring instrument did they use?

Jeff

 

I think he was both frustrated and angered by me, for asking such a "stupid" question where I asserted that heel bisections had such poor inter-examiner reliability that it made no sense to use heel bisections as a way to fine-tune foot orthosis therapeutic modification, but he was also frustrated and angered by his profession for not being as accurate in their measurements as he thought he could be.

I agree with Simon. The Root method of calcaneal bisection is associated with a great degree of inter-examiner error. If even the biomechanics professors taught by Mert Root can't do it the same way, even though they were personally trained by Dr. Root, what does that say about the rest of the profession who aren't biomechanics professors, haven't been personally trained by Dr. Root and who somehow think that the calcaneal bisection actually has something to do with the kinetics of the foot and lower extremity in gait?

I do agree with you that the subtalar joint (STJ) axis palpation technique is a difficult to master technique. However, there are multiple methods of estimating the STJ axis spatial location which I have written about before which can be used to check the measurement. The STJ axis palpation technique has been validated by our Belgian podiatric colleagues and, unlike calcaneal bisection, STJ axis location has significant effects on the kinetics of the foot and lower extremity in gait.

And, responding to Daryl's assertion that somehow the center of mass of the calcaneus is important, if that is the case, why are we bisecting the calcaneus only on it's posterior surface? Why aren't be bisecting the calcaneus on its lateral surface, its plantar surface or on its medial surface if this is so important? And why aren't we bisecting the talus which is just as important in the function of the STJ and probably more important in midtarsal joint function than the calcaneus?

Finally, Eric Fuller is right. The moment of inertia of the calcaneus is an insignificant issue when one assumes that the accelerations of the calcaneus are so small during the stance phase of gait and the mass of the calcaneus is a small fraction of the mass of the lower extremity as a whole. Why waste our time calculating moment of inertia of the calcaneus? Why not spend our time calculating the moment of inertia of the talus and navicular? Why? Because when it comes down to the biomechanics of the foot and lower extremity and the pathologies we all treat, it is the forces and moments that are the cause of the injuries we see, not the kinematic patterns.

We need to spend less time worrying about position (i.e. calcaneal bisections, tibial varum) and spend more time worrying about forces and moments and 1) how they are causing the pathologic tissue forces which are causing the injuries in our patients, and 2) how these pathologic tissue forces can be reduced with our conservative and surgical treatments in order to reduce the pain of weightbearing activities, optimize the gait function and prevent other pathologies from occurring.

It's time to start thinking more like engineers and how we can use their time-tested modelling techniques of engineers to better understand how our foot orthoses work and how we can better utilize our foot orthoses to speed healing and improve the gait function of our patients. Mert Root and his colleagues gave us a good start, now its time to use our new knowledge to continue to improve podiatric biomechanics well into the 21st century.

 

Daryl, are you familiar with the test that I have described as the maximum eversion height test. Have a patient stand and ask them to evert. While looking at the heel you can see how much residual pronation they have in the forefoot and the rearfoot. You can see this without drawing any lines. I came up with this test when I was teaching the biomechanical evaluation and attempting to show the students that you could calculate how much eversion there should be available in static stance. After getting frustrated by the numbers not always working out and having to explain to the student that there is error in the measurements, I thought why not just look at the foot to answer my question of whether or not there is range of pronation available in stance.

Daryl, we can model structures of the foot without doing those end of range of motion measurements. So, we can look at what you use these measurements are used for, (Thanks Jeff for a partial list) and then figure out if these uses can be done without drawing lines. For example, looking at range of motion of the STJ to assess for a tarsal coalition. Once you learn to feel for STJ motion, you can assess whether or not their is a coalition just by trying to move the joint. Conversely, the lines can be misleading. You can get a significant amount of frontal plane motion of heel relative to the leg with just ankle joint motion.

Daryl, since you are the one claiming that moment of inertia of the calcaneus is important, shouldn't you be the one to providing the proof? Anyway we don't need no stinking engineers. We don't need to look to a higher authority. We can just look at the formulas ourselves and make up our own minds. Quickly, the only formula that I can think of where moment of inertia is important is looking at angular acceleration. (Moment = moment of inertia x angular acceleration). This is important for inverse dynamics. However, if we are doing static analysis, I don't see how moment of inertia of the calcaneus is important. Can anyone come up with why and when moment of inertia of the calcaneus would be important?

Isn't this what finite element analysis is for? A force applied to the fifth met head will create a force and a moment at the 5th met cuboid joint. The force and moment on the cuboid will create a force and a moment on the calcaneus and this can create a moment about the STJ. Now, if we model the MTJ as two somewhat joints that are surrounded by ligaments we can look at which ligaments will have increased tension and which joint surfaces will have increased compression. Those joint forces will allow the distal forces to be "transmitted" proximally to create an effect on the more proximal joints. However, if we model the MTJ as a universal joint with two independent axes of motion we will just be waving our hands and believing in magic.

The problem that I see with medial flares in controlling pronation is that there effect is too late in normal heel to toe gait. In gait, the lateral heel contacts, the lateral forefoot contacts and pronation starts. In a medially deviated STJ axis there will be a greater moment from ground reaction force (we can regard the moment of inertia of the calcaneus as a constant for this scenario as it will be the same for medial and lateral deviated STJ axes.) and there will be a greater pronation acceleration. I've always believed that it is the stopping of pronation that is the problem and not the pronation motion itself. That said, in static stance, it is conceivable that a medial flare could be helpful.

Eric

 

Kevin,

I agree that we are concerned about forces and reducing pathological forces. That is the purpose of a functional orthosis. Position of the osseous members and segments is one indicator of the nature of the forces that are acting within and on the foot. For example, when you walk down a crowded city street and can easily see a woman with adult acquired flatfoot, it is the position of her foot as seen through the broken down upper on the medial side of her shoe that tells us the nature of her problem. So I would say we need to worry about position and forces equally. You can't see forces, you can only see their result.

Jeff

 

The tractograph that was available in the CCPM student book store.

 

Eric,

Exactly. Not the forefoot measuring device that Merton Root developed specifically to measure forefoot to rearfoot relationship. A tractograph really isn't a very good instrument to measure forefoot to rearfoot because of the distance between the forefoot and the rearfoot and because the practitioner has to eyeball the planes rather than being able to place the forefoot measuring device on the posterior heel bisection line and the plane of the forefoot at the same time. So we have practitoners who don't use the instrument that Merton Root developed and don't use the heel bisection technique he described making judgments about the accuracy and validity of Root's theory and methodology, even though they don't follow it. Maybe we should test the stj axis location technique using a 16 ounce ball peen hammer and then claim that our finding are different. :dizzy:

Jeff

 

That's funny, Jeff. No one in the CCPM biomechanics department used this device during either my student years or during my Biomechanics Fellowship. We always used a tractograph to measure forefoot to rearfoot relationship. In addition, in all the time I spent with John Weed, Ron Valmassy, Chris Smith, John Marczalec, Bill Sanner, Rich Blake, Lester Jones and others during my years at CCPM, they never once told me I was losing accuracy by using a tractograph instead of the device your father developed. In fact, they said it wasn't necessary to use that device your father developed to do accurate forefoot to rearfoot relationship measurements.

What is even more funny is that when I saw one of these devices at the CCPM bookstore and looked closely at it, it wasn't even named "Forefoot Measuring Device", it was rather named "Forefoot Varus Measuring Device". In fact, Jack Morris, who became a professor of biomechanics at CCPM while I was a Biomechanics Fellow commented that when he was student, all the patients seen at CCPM had a forefoot varus and when he returned 15 years later to teach biomechanics to the podiatry students in 1984, all the patients seen at CCPM had a forefoot valgus deformity. I suppose the population of patients changed remarkably during that 15 years...or perhaps it was something else?...

These are all true stories and is one of the reasons I was so interested during my Biomechanics Fellowship in 1984-1985 in moving away from these erroneous and sometimes useless measurements in making orthoses. All of these inconsistencies in these measurements do not tend to reinforce the idea that calcaneal bisections, subtalar joint neutral and measuring forefoot to rearfoot relationships is either easy to do or very reproducible from one examiner to another.

I think that Daryl and Michael the Unknown are still big promoters of these ideas, but, really, who else is lecturing on these subjects still at large podiatric seminars? I know of no one who still is. What does say about its future?

All that being said, I do believe structure influences function and that Dr. Root had a good initial idea, but that his measurement techniques were just too variable to produce enough consistency to be used to predict pathology or predict gait function. I think better measurement techniques are out there, but we just haven't found them yet.

Happy New Year!:drinks

 

Kevin, Happy New Year to you too! :drinks and for tomorrow, :morning:

 

Happy New Year...even to the nattering nabobs of negativism. A New Years treat to stimulate the senses on what could, and should be.

http://youtu.be/7BSetRI_UH4

 

Michael, you probably haven't read the work of Prof. Chris Nester since he's "just a chiropodist from the UK", however, I really think you should read his work since he and his team have provided the best data to date on how the bones of the human foot move in-vivo. Here's your starter: http://www.jfootankleres.com/content/2/1/18

Then you may wish to read the PhD thesis of Hannah Jarvis, one of Chris's research students here in the UK: http://usir.salford.ac.uk/29381/1/HannahJarvis_PhDThesis.pdf

These pieces of literature might help you in beginning on a journey to better able differentiate reallity from illusion and wishful thinking.

 

Simon, I think you're being a little rough on Jeff in your anti-Root dogmatism.

I would like you to return to the pre-Root days. What are your thoughts in regards to the 1898 paper by Lovett & Cotton, in which they proposed that flat feet became symptomatic when a patient used their entire reserve of pronation. Do you believe this hypothesis?

Now if you answer yes, please explain for me, if Clarence the arch-angel eliminated that Mert Root existed, what is the Spooner method for determining whether a patient was using their entire reserve of pronation in static stance?

I do say that you have correctly identified the problem with tissue-stress models. There is currently no quantitation (except in the most high tech biomechanics laboratories that can compute joint moments in multi-segment foot models which are only in their earliest stages of development). Eric has never really proposed predictive clinical methods beyond what Kevin already proposed in finding the STJA. I view most of his discussions as being like a medical examiner telling you how a person died, not in predicting when and how a person will die. I'm also disappointed that the "tissue-stress" model discussions only ever revolve around STJ axis, and never discusses any other joint axis within the foot. Whatever your personal biases for Root, he actually did discuss many times the need to know variations in other joint axes. Not saying he correctly what the various joint axes are and the methodologies to determine them, but he did at least maintain that they are all important.

BTW - if you want to introduce nationalism into your posts, it really doesn't become you. This is not about any country having a monopoly on truth. Podiatry has some different traditions in our two countries, and both are honourable traditions. Each can point to successes and each can point to failures in the pursuit of truth. I'm glad that you are proud of the English successes, but remember that America has basically the same roots. We just figured out how to successfully redo the Peasants Revolt of 1381 and George III wasn't as smart as Richard II.

Happy New Year (G-5)
Daryl

 

I think that Kevin tends to characterize me in his own views of the world. Yes, I do believe that measurement is essential to understanding function and etiology of function. I look at Mert Root as the guy who really pushed our profession to start thinking of biomechanics as a science. He proposed taking a series of measurement in a book that I have been calling for over 25 years an idea book, not a technical book. There are so many things in the book that are not well defined, that it is a wonder the intertester reliability that has been reported over the years has been as good as it has been reported. I believe that my 1992 paper added additional detail in the measurement techniques for the STJ, which I used to determine that the Kirby proposal of the STJA axis fit the measurements that we could take clinically. Interesting, Kevin, that I proposed taking angular measurements in two body planes and linear translation measurements in one plane to show that your axis model could be relied on. Guess that makes me a Root-puppet, eh? Guess my 1983 paper was only a Root technique. Haven't seen any other papers proposing other FF-RF quantitative measurements.

I do agree with you, Kevin, we need better definitions and also many more measurements than Root proposed. I see the Root measurements primarily as a philosophical approach than a technical approach. The philosophy is understanding the etiology of symptoms and deformities and the first step toward predicting pathology. 80% of orthotics can still be made w/o any of these measurements, but that doesn't mean I don't do them, as I learn something every time I do them. Interesting that I published a paper on trying to determine the direction cosines of the STJA before you graduated, Kevin, and that I was the first person to publish anything to independently support your STJA proposals and further quantitate them, going so far as to present it at the International Congress of Biomechanics on my dime. Guess that makes me really stuck in the Root paradigm. Guess my presentation at ACFAOM this last year, which paper is being finished, about the investigation of the medial and lateral plantarflexion angles of the forefoot makes me just another Root-parrot.

Believe it not, I do believe that if nothing else, Root be remembered for his philosophy and the way he influenced our profession to start being more scientific and more mechanical. I want to keep everything good he did, but replace the inaccuracies and the incomplete ideas he had. I have always totally disagreed with Chris Smith's methodology of doing calcaneal bisections, which seems to have been the pervading theory that came to dominate those late 70s-early-80s days at CCPM when you were being trained. Guess because Chris had such a dominating personality that he was able to forego strong questioning on his mechanical reasoning. I decry those who believe that Root created the complete Bible of biomechanics and that after Root that the Canon was closed. I saw no one, when I was a student questioning that Bible nor trying to add to it, except maybe Root himself. Fortunately, I had extensive exposure to a strong mechanical engineer who was questioning Root long before I met Weed or Root. And I had a father who started working on ideas to improve Root, long before I thought of entering the profession. So I have a long history, as long as Kevin's, in saying it is necessary to keep moving forward; but we don't have to have this continual diatribe that reverberates throughout this forum about all the bad things Root did and that we would be better off without him. Nor do I believe that anyone who contributes to this forum has replaced Root as one of our profession's foremost thinker in clinical biomechanical practice.

Happy and prosperous and healthy 2015 to all
Daryl

 

It would seem reasonable to assume that as the joint approaches its end of range of motion for a given applied load then the stress in the tissues which restrain the motion in that direction should increase. However, if all of the restraining tissues are functioning within their zones of optimal stress (ZOOS), then there is no reason why such a position should result in pathology and symptoms. If, however, this position results in excessive stress within one or more of the restraining tissues and the tissue is functioning outside of it's ZOOS then symptoms and pathology may ensue. Lets think about the interaction between the talus and calcaneus at the floor of the sinus tarsi as being the restraining tissues here: depending upon the magnitude of the compressive forces and the load/ deformation characteristics of the bones involved which will in part be determined by the trabecular organisation of the compressive segments of bones here, the subject may, or may not experience symptoms. Lets say the compressive force between talus and calcaneus at the floor of the sinus tarsi is X, the STJ is at it's end of range pronation, but the subject remains asymptomatic, we now increase the compressive force to 2X, the position has not changed perceptably (though microscopically it has) but the forces between the bones have and despite our imperceptable change in position symptoms may now arise.

Whether or not static foot posture predicts pathology can probably be better answered by my colleague Ian Griffiths, an outstanding UK podiatrist that I have had the privilege of mentoring for a number of years now and who recently co-authored a meta-analysis of the subject.

Well we could use the method defined by Eric earlier. Where do you want to measure this pronation? This is important since while one joint might be "running out of it's pronation reserve" another may have loads left. Moreover, "Pronation and supination of the foot, and the associated “pronated” and “supinated” foot types, are popular terms used to simplify the combined movements of the multiple joints of the rear, mid and forefoot bones. However, it is often assumed that these concepts apply to individual joints or combinations of joints in the foot. The data here, however, reveal that joints are capable of complex combinations of frontal, transverse and sagittal plane motion and are rarely constrained to pronation and supination patterns."- http://www.jfootankleres.com/content/7/1/51 So, I guess you might need to be more specific, Daryl.

You might need to review our discussions more closely then, Daryl. A quick search of this forum will lead you to many discussions regarding rotational equilibrium around pretty much every joint of the foot, if not the entire lower limb, here for all to read. You may also wish to read Kevin's textbooks in which specific chapters are devoted to such discussions. I presume that you have read all of Kevin's books, Daryl?

As for prediction, again I refer you to the meta-analyses recently published by my colleagues so that we can see what the published literature actually suggests here, as opposed to what the superstition might have us believe:
http://www.podiatry-arena.com/podiatry-forum/showthread.php?t=100560

And if an anonymous American podiatrist wants to say

We can ignore the nationalistic commentary which was initiated by Michael, who judging by his avatar thinks he's still in 'Nam, serving Ol' Glory, right Daryl? Anyone who has researched the history of biomechanics and foot orthoses realises that podiatric biomechanics neither began nor ends in the good ol' US of A, nor with good old Mert, God rest his soul; rather that contributions have been made to the science by workers from many nations and continue to be made to this day.

 

When I read lines like:

by Michael the Unknown, all I can think of is this man....

Maybe we should call him, instead, Ned the Unknown...

 

Believe whatever you wish, Daryl. I'm not the thought police. Yet, I beg to differ and would be so bold as to suggest that a great many of my colleagues around the globe might disagree with you also. There are a number of thinkers on this forum who would now tie Root in knots when it comes to understanding podiatric biomechanics, yourself included. There are some who's professional output far outweighs that of Root both in quality of content and quantity of volume. I guess it all depends on your point of view.

 

How do you know he's not still having flashbacks of 'Nam, Jeff? I don't know, I wasn't there . Yep, going out shooting defenseless sitting ducks on a pond, better make sure you come in full Rambo gear . Here in the UK, they tend to wear plus fours and tweed, and use a dog to enter the water. No face camo nor chest waders required. How brave though to enter the water in the face of such a vicious creature as a duck, you better make sure you've got an assault rifle with you for that mission or an Uzi 9mm. Hmmm (for the record, I don't nor wish to try to fathom the gun laws in your country). Let's just hope those chest waders don't fill up with water nor a rogue duck pecks at an eyeball (I presume that's why the sunglasses are deemed necessary in spite of the fact that the reflection from them undoes any stealth secured by the face camo) .

No shooting fish in a barrel, nor ducks on a pond here; never fear.:drinks

I honestly thought his name was Michael Hunt because no-one has seen him due to his face camo...
Seriously, have you seen Mike Hunt? Quick tap on the crash cymbal. I thank you.

 

Simon's response to my introductory, instructional video targeting MD's is both predictable and indicative of the closed-minded attitude he has towards others in our profession. He attempts to reconcile his acerbic demeanor by citing studies that were produced in the UK that supposedly support his viewpoints. OK...let's look at those studies. Nester, himself, discusses the inherent problems of replicating 'in vivo' motion utilizing dynamic cadaver models, but double downs on his bet that the study is worthwhile when he wrote: "Furthermore, there is clear evidence that in some feet the ankle displays more frontal and transverse plane motion than the subtalar joint, which was traditionally perceived as the rearfoot joint most able to move in these planes. In the case of transverse plane motion, Lundgren et al [26] reported that the total range of ankle motion was greater than the equivalent subtalar motion in 3 of 4 participants (in walking)." Wow! Now that would be shocking....wouldn't it? More transverse(axial) and frontal(coronal) plane motion at the AJ than the STJ? OK...so let's look at Lundgren's work cited: "Movement between the talus and the tibia showed the expected predominance of sagittal plane motion, but the talocalcaneal joint displayed greater variability than expected in its motion. Movement at the talonavicular joint was greater than at the talocalcaneal joint and motion between the medial cuneiform and navicular was far greater than expected." So how could Nester et al come to the conclusion that more AJ motion occurs in the frontal and transverse plane than at the level of the STJ? Is this an indication that cadaver studies are flawed? One only needs to consider the axis of motion of the AJ in the cardinal planes to recognize that this is not correct...yet Simon argues that the sky is not blue, the world is not round, Root was wrong and only Spooner is correct.

So based on some UK studies, our profession is reduced to arguing whether, or not, the AJ is a ginglymus? This was precisely the point I was trying to make in some of my posts...there is no uniform agreement in our profession about much of anything anymore it appears...as some argue that the AJ is not a hinged joint, forefoot varus doesn't really exist, the calcaneus doesn't need to be bisected, etc, etc...ad infinitum, ad nauseum.

Perhaps we should all take a step back and stop the dogma, take the blinders off that limits our perception of normal vs. abnormal and stop nitpicking. When I showed the above video to other Podiatrists, I could sense "light bulbs turning on" in their heads, as they realized the possibilities of such an endeavor. It appears that Simon's filament is burned out. The video was produced several years ago, (although only copyrighted this past year), but previous to that, I had never seen a video that depicted STJ motion to any mentionable degree. Yes, there are flaws with the video...but considering that it took me ~10 bunion surgeries, (at current reimbursement rates), to pay for that animation, one can understand the constraints on 'out-of-pocket' expenses being the limiting factor in producing instructional videos. Nonetheless, it should be a sign to most thinking people that this is the direction we need to go to quickly, efficiently and as accurately as possible, disseminate this type of information. The possibilities are only restricted by our lack of vision and/or our unyielding and myopic view of Podiatry.

Getting back the Roots of our profession, (pardon the pun), is perhaps, the reason I discovered the cause of GPs in children and tied it to at least a subset of RLS adult patients. I have been 100% successful in treating GPs patients, and have an 83%, (but climbing since the pilot study), success rate in RLS patients.

Kevin....last night I attached my signature to my profile, and my name was attached on the video I so willingly gave this community in good faith. It would've been easy to determine that on your own just by clicking on my avatar. And Simon...that pic I used is from a day duck hunting out in the swamp, (called wildfowl hunting in the UK), which anyone that has any experience at, should've known. I didn't serve my country in the military, Vietnam or otherwise. No....I guess that solving a mystery in medicine that is nearly 200 years old in the case of GP, and dates back to the 1600's in the case of RLS, will have to be my substitute for something as honorable as serving.

 

Michael,
Bless your cotton gusset. I only hope that one day, I can have such an understanding of contemporary biomechanics that you believe in. Maybe some of your over exaggerated self-confidence too. I just didn't see a whole lot of frontal plane motion occuring at the talo-crural joint in your animation, your discussion of the coupling of this joint notwithstanding the scientific data. Maybe we should drop a line to Chris, and he can come and defend his own article here?

That "nationalistic thing" you were talking about Daryl... would you like to have words here?

P.S. Sorry that I didn't recognise the picture of you duck hunting which is called "duck hunting" here in the UK, since we don't dress like pricks to carry out the slaughter of defenseless animals in this country. Actually, I take that back, they do dress and act like pricks, they just don't pretend to be Rambo.

Luckilly Michael is the resurrection and the life for us all to follow into 2015 when it comes to podiatric biomechanics, we'll all be alright...

https://www.youtube.com/watch?v=qyrrTK_xzj4
"Down down you bring me down
I hear you knocking down my
Door and I can't sleep at night
Your face it has no place
No room for you inside my
House I need to be alone

Don't waste your words I don't need
Anything from you
I don't care where you've been or
What you plan to do

Turn turn I wish you'd learn
There's a time and place for everything
I've got to get it through
Cut loose 'cause you're no use
I couldn't stand another
Second in your company

Don't waste your words I don't need
Anything from you
I don't care where you've been or
What you plan to do

Stone me why can't you see
You're a no one nowhere washed up baby
Who'd look better dead
Your tongue is far too long
I don't like the way it sucks and
Slurs upon my every word

Don't waste your words I don't need
Anything from you
I don't care where you've been or
What you plan to do

I am the resurrection and I am the life
I couldn't ever bring myself
To hate you as I'd
Like

I am the resurrection and I am the life
I couldn't ever bring myself
To hate you as I'd
Like"

 

Yep...that is the most glaring problem with the animation as depicted...not enough frontal plane motion of the calcaneus. But the talus sliding forward and inward on top of the STJ, I had never seen before in any other animations...Dr. Glass or Dr. Glasers' in particular. Light bulbs, Simon...light bulbs should have gone off in your head...but they didn't...did they? Finding a reliable animator has been my problem to this point, but them performing the rigging and showing frontal plane motion in the calcaneus is not a problem for them at all. It just takes time and money. Tell you what...spend some of your surgical reimbursement capital on your own animator and produce your own contributions to our profession to aid those already in practice and those that are in school. Wait...UK Podiatrists don't perform surgery...do they? Then take some of your "speakers reimbursement" salary that certainly pads your already prodigious CV and do the same. Then get back to me when that effort has resolved anything in our profession that is lasting, meaningful and potentially effects millions of people.

FWIW...Brits love to shoot snipe...they revere them as delicacies and eat them on toast...entrails and all. The similarities between that activity, and reading the contents of your posts has not escaped me.

 

Yeah, I think it was Manter that described anterior displacement of the talus on the calcaneus during subtalar joint pronation when he talked about a helical screw-like axis in 1941. I guess that light-bulb went off a long time ago in my head, maybe 25+ years ago, nothing new. You may have missed this from Nester though: "Variation between people in foot kinematics is high and normal. This includes variation in how specific joints move and how combinations of joints move. The foot continues to demonstrate its flexibility in enabling us to get from A to B via a large number of different kinematic solutions.", you only seem to be showing one possible solution in your video. Serious question: why are you paying animators to develop these videos for you? What is it that you hope to get out of them other than your own financial reward?

Your xenophobia is outstanding in it's lack of knowledge and understanding, BTW.

Your finally analogy makes you snipe, but I don't do "hunting" and I certainly don't eat that, nor know anyone who does- I'm not sure where you are getting your information about the UK from, maybe it's the cartoon network. Yet you are clearly xenophobic.

 

"Sorry that I didn't recognize(sic) the picture of you duck hunting which is called "duck hunting" here in the UK, since we don't dress like pricks to carry out the slaughter of defenseless animals in this country. Actually, I take that back, they do dress and act like pricks, they just don't pretend to be Rambo."

"WE", Simon? I'd be extremely nervous around you if you ever had a gun in your hands, even if you knew how to use it. Yeah...I love the way Brits hunt fox over there...so "sporting", isn't it?

You are the epitome of a nattering nabob, because it really doesn't matter what the subject is, you extend your dogmatic attitude to include every subject or anyone that offers contrarian opinion or research....even to the point of "calling out" rdp1210? Really, Simon...how very Spooner of you...a legend in your own mind. Too bad few others share your views, of yourself or your dogma. I think a new quote needs to be generated. "When all one has is a hammer, the world looks like a nail", needs to be revised to incorporate Spoonerisms. "When only Simon has the hammer, everyone else's world is his nail". Pound away, Simon...and enjoy your entrails.

http://www.celtnet.org.uk/recipes/m...p?rid=misc-becassine-farcies-sur-des-croutons

http://www.celtnet.org.uk/recipes/m...pe.php?rid=misc-glasse-roast-woodcocks-snipes

 

Thankfully we banned fox hunting with dogs here some years ago. Glad to see you've kept up to date with UK politics and cuisine as much as you have with podiatric biomechanics and UK podiatric surgery. I'll call Daryl out every time I think he is academically wrong, as he will I, since we have known each other academically for over twenty years. For the record, my first personal contact with Daryl was a phone call regarding what I believed was an error in one of his equations in a paper he had published. I was overwhelmed by his courtesy and impressed by his intellectual ability- remember that call, Daryl? It was the beginning of a long academic journey for me which I am still treading. As such, Daryl holds a very dear place in my heart. So don't dare come here and start professing to me about my relationship with Daryl, when you know nothing about it. We may disagree and agree with one another in academic debate, yet remain courteous and respectful of one another when we come together at meetings and share a joke and a laugh. I consider him to be one of my professional friends. What you also don't know is that Daryl and I, along with many others here discuss things privately, away from Podiatry Arena. Why do you think Daryl might send me a private e-mail to ask my opinion on something, or I might he? You have a lot of learning to do, young man. Start by winding your xenophobic neck in.

By the way, here is what the word "nabob" means: http://en.wikipedia.org/wiki/Nabob since those that you accuse of being "nabobs" have to the best of my knowledge, never worked for the East India Trading Company, it seems that once again your commentary here, just as it does in your youtube videos, lacks any accuracy and validity.

 

Daryl, that is a false choice. We can keep the parts of Mert Root's teachings that we like and we can discard what we don't like. I like the concept (but not the naming) of a partially compensated varus. I like the concept of the intrinsic forefoot valgus post. I've worn many different orthotics and the ones I like best have a small intrinsic valgus post.

Daryl check out this thread where I described the maximum eversion height test.
http://www.podiatry-arena.com/podiatry-forum/showthread.php?t=69635

I also think the maximum eversion height test is a better predictor of what amount of intrinsic forefoot valgus post an orthotic should have. The forefoot to rearfoot measurement is done in neutral position. Daryl, you did the study that showed that the forefoot to rearfoot measurement changes with STJ ROM. If a foot is not standing in neutral position then the measured forefoot to rearfoot has little relevance with the foot that is standing in front of us. This is on top of the measurement accuracy problem.

I prefer the term pronation range of motion available to reserve of pronation. To me, reserve of pronation implies that there is supposed to be range of motion available. We look at the feet in resting stance position. Some will have eversion range of motion available and others won't. The term reserve implies that there is supposed to be some range of motion. We don't have any reason to beleive that a foot is supposed have eversion range of motion.

Daryl, are you really being critical of tissue stress approach because of inability to measure? People who live in glass houses shouldn't throw bricks. One of the major reasons I like the tissue stress approach is that you can use it without precise measures. You identify the tissue under too much load. You model that tissue for changes that you can make clinically to figure out which changes will reduce the load in the anatomical structure that you are concerned about. You can do this without measuring the stress. For example, a patient with peroneal tendonitis. You assess their STJ axis position and note that it is lateral. Let's just say that you measure to the best of your ability that the patient has a 5degree forefoot valgus. When you ask them to evert, you note that the height the lateral forefoot gets off of the ground is equivalent to a 2 degree intrinsic forefoot valgus post. So, what should we do for this patient? I"ve made the mistake of giving a patient like this a 5 degree intrinsic post and seen that when you attempt to evert the foot farther than it can go it will hurt. I've learned that forefoot to rearfoot measurement does not only have poor accuracy, it is not a valid way of producing an orthotic prescription. Oh yea there is the other theory on how orthotics work. You make the foot more stable by pushing them toward neutral position. (Don't criticize this characterization it's not important to the point I'm trying to make) So, this patient with peroneal tendonitis stands with 5 degrees of heel eversion available. Their neutral position is 5 degrees inverted from their resting stance position. Should we push this foot toward neutral position or away from neutral position with our orthotic to improve symptoms? I'd use a lateral heel skive and forefoot valgus post that would match their maximum eversion height. I come to that prescription without ever bisecting the heel.

drhunt1 (can I call you 1?) This reasoning is not too complex. It is quite simple and the measurements that I took to get to this prescription took less time than it does to perform a standard biomechanical evaluation.

Eric

 

Daryl, I'm not sure what you are saying about Chris Smith. I found that he would listen to arguments and he made good observations. One of my proudest moments occurred just after I finished the fellowship. Still new, and not very confident I has a conversation with Chirs Smith, someone who I respected highly, where he came back to me later and said that I had changed how he thought about the foot. I regret that I couldn't change his thinking further, but I did find that he listed to reason.

Daryl I am not saying that Root did everything wrong. What I am saying is that we should discard the stuff that he did get wrong. Our current debate is about what things he got wrong. We will continue to have diatribe as long as we disagree about whether Mert Root got something wrong. I see no reason to limit this debate.

Happy new year to all.
Eric

 

Thanks for that, Matt. For the others following along, drhunt1 is Matthew H. Sciaroni DPM, age 59, who practices in Fresno, California.

http://www.healthgrades.com/provider/matthew-sciaroni-3ck55

And this piece of information was a very interesting read....

http://www.vp-medical.com/legal-nurse-consulting/podiatrist-performs-breast-exam/

Here's some more information on that process..

http://abclocal.go.com/story?section=news/local&id=6159210

 

Eric,

Are you aware that Chris Smith doesn't think the calcaneus can become everted and that lateral displacement of the plantar fat pad creates the appearance of and everted calcaneus? Do you agree with Dr. Smith about this?

Jeff

 

I would certainly agree that movement of the fat pad can make a heel bisection drawn on the skin more everted. A line that moves relative to the bone might be more indicative of pathology than a line that doesn't move and is everted.

I've been moving away from heel bisections and don't really have a problem saying that calcanei don't evert. It's all a matter of where you draw your line.

Is an everted calcaneal bisection a problem?

Eric

 

Kevin-and that is PRECISELY why I wanted to remain anonymous until after the article was published...because I didn't want the discussion to be about my obliterating Jim Rathlesberger and the Podiatric Board in a court of law, and I did not want dipwads, like yourself, to post ad hominem arguments against the information I presented. Thank you for again making my predictions prior to this, a reality. You're way too predictable. In discussions with the co-author...someone you know quite well and have sent surgical patients to, this is EXACTLY what we discussed. Your posts actually drip with professional jealousy, Kevin...is it because you missed the diagnosis of GP and the connection to RLS, or because I discovered it? And fwiw...I knew this information before the Podiatry Board had me arrested and brought charges against me. How many millions of patients have suffered needlessly because I had to defend myself, soaking up the finances that could have been put to better use, YEARS before I achieved this? Further, at a lower burden of proof, the Podiatry Board walked away from any administrative action against me. Any attorney worth his weight that has seen the evidence knows this was a case that never should have gone to trial in the first place, and apparently, this information didn't bother Valmassy when he agreed to peer review the material. But you're a small man, Kevin...thanks for clarifying that to anyone that reads this blog that has a modicum of intelligence. Perhaps we'll meet again at a seminar and you can tell me to my face how you feel about what you posted...won't that be fun?

 

Sorry that you got so upset that I posted some things from my 5 minute internet search on you, Matt. This never would have happened if you had told us your name right off the bat. Then I wouldn't have had the curiosity to look on the internet for who you are. Honestly, I can't remember ever meeting you or discussing anything with you over the last 30 years. I do have lots of people I have never heard of before asking me for my advice by calling me or e-mailing me out of the blue. Maybe I just forgot.

I really could care less if someone accused you of something you didn't do. If you say you didn't do anything wrong, then I believe you.

And as far as professional jealousy, why would I be jealous of you?

Now that I know who you are, Matt, can we get back to the discussion at hand? Let's just stick to the topic of biomechanics. I think everyone following along would appreciate that.

 

Jeff:

I heard Chris say that type of thing when I was a Biomechanics Fellow. I just ignored it. I did notice that Dr. Smith drew his calcaneal bisections more inverted than anyone else in the CCPM biomechanics department. Of course, if you draw your heel bisections all more inverted than anyone else, there is less likely that the heel will ever become everted. It was exactly these big differences between my Biomechanics Professors in the results they each obtained from examining the same patient that made me want to not rely on "calcaneal bisections" or "forefoot to rearfoot relationships" in order to make the best custom foot orthoses for my patients.

 

I would agree with Eric about Dr. Chris Smith. He was always willing to listen and was very smart man to bounce ideas off of. Since he had been around CCPM for so long (he and John Weed were classmates), I often sought him out since he was a wealth of information on the early days of Root versus the early 1980's philosophy that had developed within the CCPM Biomechanics Department. We argued a lot but we had mutual respect for each other. I learned a great deal from Dr. Smith during my student and Biomechanics Fellowship years and feel that without him, the CCPM Biomechanics Department would have much weaker during my years there.

 

You're not worth any more of my time, Kevin...and you confirmed my opinion of you above. In closing to your comments, let me give you a great quote by Eleanor Roosevelt: "Great minds discuss ideas; average minds discuss events; small minds discuss people." See you at the next seminar....

 

Daryl:

You are wrong when you say that the Tissue Stress Model involves discussions only around the subtalar joint (STJ) axis. Like Simon said, many of us have been discussing Tissue Stress around multiple joints over the past few decades.

Whether you know it or not, Eric Fuller and I coauthored a book chapter on Tissue Stress Theory in 2013 where we discussed the modelling of forces and moments about the knee joint, ankle joint, STJ, midtarsal joint and 1st metatarsophalangeal joint (Fuller EA, Kirby KA: Subtalar joint equilibrium and tissue stress approach to biomechanical therapy of the foot and lower extremity. In Albert SF, Curran SA (eds): Biomechanics of the Lower Extremity: Theory and Practice, Volume 1. Bipedmed, LLC, Denver, 2013, pp. 205-264). What is very interesting, in this detailed analysis of the forces and moments that exist within the foot and lower extremity joints, we didn't need to discuss calcaneal bisections or forefoot to rearfoot relationships even once in this 59 page chapter with 48 illustrations.

In addition, throughout each of my four published books there are discussions of tissue stress with a whole chapter in the second book dedicated to the subject of Tissue Stress which I wrote nearly 13 years ago (Kirby KA: Foot and Lower Extremity Biomechanics: A Ten Year Collection of Precision Intricast Newsletters. Precision Intricast, Inc., Payson, Arizona, 1997.;Kirby KA: Foot and Lower Extremity Biomechanics II: Precision Intricast Newsletters, 1997-2002. Precision Intricast, Inc., Payson, AZ, 2002.;Kirby KA: Foot and Lower Extremity Biomechanics III: Precision Intricast Newsletters, 2002-2008. Precision Intricast, Inc., Payson, AZ, 2009.;Kirby KA: Foot and Lower Extremity Biomechanics IV: Precision Intricast Newsletters, 2009-2013. Precision Intricast, Inc., Payson, AZ, 2014). Maybe you should, Daryl, read these books to see what I have been doing in regards further developing Tissue Stress Theory over the past few decades.

In addition, Eric Fuller has also published articles on Tissue Stress theory over the last 15 years (Fuller EA: Center of pressure and its theoretical relationship to foot pathology. JAPMA, 89 (6):278-291, 1999; Fuller EA: Reinventing biomechanics. Podiatry Today, 133), December 2000). His contributions to these ideas have been critical to their development.

Finally, when I lecture in Spain, the UK, Australia and Canada, Tissue Stress Theory seems to be the predominant theory of orthosis prescription being lectured on, with Subtalar Joint Neutral theory barely being mentioned. I am currently working on a feature article on Tissue Stress Theory for Podiatry Today Magazine which will be published within the next few months. It should be a good read.

 

In 2015, I'll be lecturing in Vancouver in April, and as keynote speaker at seminars in Manchester, UK, in June and in South Africa in August, then in New York in November. Where have you been invited to lecture in 2015, Matt?