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Challenging the foundations of the clinical model of foot function

Discussion in 'Biomechanics, Sports and Foot orthoses' started by NewsBot, Jan 31, 2017.

  1. Sarah:

    You can immediately forget the "longitudinal and oblique midtarsal joint axes". The "longitudinal and oblique midtarsal joint axes" do not exist. They are not true joint axes, but are rather a myth that has been already disproven ever since Van Langelaan's thesis from over 34 years ago (Van Langelaan EJ: A kinematical analysis of the tarsal joints: An x-ray photogrammetric study. Acta Orthop. Scand., 54:Suppl. 204, 135-229, 1983). Not a single piece of research has confirmed the existence of a longitudinal or oblique midtarsal joint axis for the past half-century.

    Here is a short article I wrote last year on the subject which you need to read and digest, then hand a copy over to the professor who is still teaching you these myths (Kirby KA: How long will the podiatric myths of the midtarsal joint survive? Podiatry Today, 30(8):66, 2017).

    https://www.podiatrytoday.com/how-long-will-podiatric-myths-midtarsal-joint-survive

    Root theory does not need to be updated. Rather, it needs to be recognized as a theory that served us well for many years but now needs to be replaced in light of the much better research evidence and better theory that we now have had for the past 30+ years. Here is a 9 year-old article I wrote on the subject (Kirby KA: Are Root biomechanics dying? Podiatry Today. 22-4):58-65, 2009).

    https://www.podiatrytoday.com/are-root-biomechanics-dying

    Also hand and this article to your professor and ask him/her what they think of this. If your"uni" does encourage you to keep "on top of the latest research", then ask yourself this question: why are the professors that are telling you to keep current of the latest research still teaching you material that has long since been replaced by better evidence and theory?
     
  2. Nonsense.
     
  3. efuller

    efuller MVP

    One reason that this is nonsense is that the two axis model gives a very incomplete picture of the motion that can occur at the MTJ. Say you chose an oblique axis of motion for the MTJ. When you move about that axis you miss the information that at any point along that axis you have some dorsiflexion and or plantar flexion range of motion and some abduction and or adduction range of motion that is not on the chosen oblique axis. The midtarsal joint has an evelope of motion. An envelope of motion is the volume of space that one part can be in relative to another part before the motion is constrained by various anatomical structures. Some feet have a much larger envelope than others.
     
  4. drhunt1

    drhunt1 Well-Known Member

    Sarah-congratulations on your entrance into the world of LE biomechanics. Yes...as you can read, this topic has been hotly debated here. I believe there are two camps of thought. First, there's the Tissue Stress Theory adherents, (of which Kevin Kirby, Eric Fuller, Simon Spooner and a few other contributors here are TST adherents). On the other side of ideology is those that believe in Root Theory of Biomechanics. I am of that camp. There used to be more, but they left because the TST adherents are generally rude and insulting. I know first hand about that. But...I'm of the belief that if you can't make a case for your theories, ie., if you can't make biomechanics more amenable to learning, (as in your case), or solve problems for your patients, (which is why we practice what we do...the healing arts), then you're just trying to create a better mousetrap, IMO. Earlier last year, I was at a seminar in Livermore, Calif. where Kevin lectured. The room was full of impressionable students and residents. Kirby actually stated that the gastrocnemius and soleus muscles can pronate the foot with contraction. I was aghast and appalled at such a stretch of reality...and left shortly thereafter. Let's take a closer look at the feud between the two camps. For example...read the following article written and published just recently in Podiatry Today Magazine.

    https://www.podiatrytoday.com/how-long-will-podiatric-myths-midtarsal-joint-survive

    But...don't just stop at finishing the article...the best part is Dr. Phillips' response. (Dr. Phillips is also a Root Theory adherent). His diplomatic dressing down of Kevin Kirby's attempt to bolster TST is classic. But the best part could be Dr. Phillips' admonition of what Merton Root told him decades ago. and that is: Dr. Root's theory was and is, a work in progress...and needed those of us to add to the limited body of knowledge available to Dr. Root at the time.

    Therefore, please take my opinion with a grain of salt, as with everyone else's here. Be wary of what walks into your office. Take copious notes, if need be...because you will begin to see patterns in patient presentations. Once you see enough patients...these patient patterns become trends, and that will lead to deciding your treatment course...that, which is best for your patients. Hope this helps...
     
  5. Dear Kevin,

    Do you have any referral or studies about : Foot orthoses are not good at changing kinematics.
    I don't really understand that because in my practice I clearly see a difference of kinematics of gait with and without foot orthoses? I can even see a difference of kinetics if I for example analyse the dynamic plantar pressure with and without plantar orthoses...

    Can you clarify this point to me please?

    Thanks for your time

    Val
    podiatrist
    Mauritius
     
  6. Mauritius:

    Did I say that "foot orthoses are not good at changing kinematics"? Better to say that "foot orthoses are better at changing kinetics than kinematics".

    Foot orthoses can and do change foot kinematics. However, the kinematic changes in the rearfoot are not consistent. In addition, most of the kinematic changes with custom foot orthoses occur at the midtarsal and midfoot joints which are difficult to measure with 3D gait analysis systems.

    Therefore, much more research is needed to determine how much orthoses affect kinematics and how the neuromotor effects from foot orthoses are regulated or modified by the central nervous system during weightbearing activities.
     
  7. Thank you for clearing this point, you did say in your previous comment (see abstract below :)) : foot orthoses are not good at changing kinematics of gait :) And it got me a bit confused! But I understand better your new explanation :)
    Sorry to be so unaware about TST but I have studied in Belgium and we mainly learned about Dr Mert Root Theory. I think ROOT theory is a very PEDAGOGIC way of teaching and I don't know yet if any theory is so well described and so pedagogic. Anyway I think I gives a good understanding of Biomechanics and from that we might be able to better understand Podiatry Biomechanics and new concepts or theories.

    How can I learn more about TST in Podiatry, is there like specific ways of assessing Tissue Stress and applicable in consultation? Maybe with a pressure plate? It seems that I can't access Podiatry Today from Mauritius so I can't read the articles you linked in your previous comment. Is there teaching materials or courses on TST?

    Best regards and thank you again for your help and time.

    Valery de Falbaire
    Podiatrist
    mauritius



    My conclusion, this was a good study that would have been much more useful 20 years ago than it is now. We now know that forces and moments cause injury and know that motion, which these researchers only studied, does not necessarily cause or predict injury. We know that foot orthoses primarily affects forces and moments and are very good at treating injury but are not good at changing kinematics of gait. However, this paper only studied the motion of asymptomatic healthy people, and did not study their plantar pressures, external joint moments, internal joint moments, tendon or ligament forces, central nervous system efferent activity to lower extremity muscles or joint loading forces, all measures which may produce injury.
     
  8. Val:

    Send me your private e-mail address and I will send you everything I have written on Tissue Stress Theory. Glad to hear your thought processes have moved you towards Tissue Stress Theory. I gave up on Root Theory about 30 years ago!

    kevinakirby@comcast.net
     
  9. drhunt1

    drhunt1 Well-Known Member

    And it shows.
     
  10. I know you wrote this a negative, but it it is a positive really
     
  11. Dear Kevin,

    My email is valerydefalbaire@gmail.com

    I wouldwbe very happy to read more about TST.

    Best regards,

    Valery
     
  12. Dear Drhunt1,

    To become a better Podiatrist I need to learn about all new theories and I am happy that Kevin is willing to share with me some articles on TST. I will read them and have my own opinion, maybe try to implement it in my practice and test it.

    My training was based on Root and I understand Root theory but I like to always learn and try new things, challenge myself and others.
     
  13. Jeff Root

    Jeff Root Well-Known Member

    Last week I attended the International Foot and Ankle Foundation’s 31st Annual Lake Tahoe Conference. There were two excellent lectures on the surgical correction of flatfoot and the surgical correction of the cavus foot. The biomechanical descriptions of the function and structure of these feet was dependent on terminology and theories derived from Root theory and Root’s neutral position classification system. For example, in the cavus foot the degree of rearfoot varus, the degree of forefoot valgus, and the degree of plantarflexion of the 1st ray present in the foot and the degree of surgical correction of these conditions was directly related to Root’s neutral position classification system. These excellent lectures require an understanding of Root theory, in part, because the deformities being discussed depend on the practitioner’s understanding of Root’s criteria for normalcy and his definition of what constitutes a rearfoot varus, a rearfoot valgus, a forefoot varus, a forefoot valgus, a plantarflexed 1st ray and a metatarsus primus elevates. Although none of the lecturers used the term tissue stress theory, they did discuss the need for tendon transfers and other procedures such as osteotomies to alter forces and biomechanical function and to address tissue stress that resulted from malfunction of the foot such as the rational for transfer of the peroneus longus tendon. The descriptions provided in these lectures would not have been possible without Root Theory and could not possibly be replaced by tissue stress theory which has no such system of structural classification of the foot.
     
    Last edited: Feb 5, 2018
  14. efuller

    efuller MVP

    Certainly Mert Root helped reinforce the use of the existing terms varus and valgus. However, these terms were in existence before Mert thought up the circular definition of neutral position when he was in the shower. You can also describe the problems of cavus foot without reference to neutral position. Yes, you will have to use the terms varus and valgus and talk about position of joints within their range of motion. However, you can do all those things without every knowing about the concept of neutral position. So how did they use neutral position in their description of their patients problems? Or did they just use varus and valgus without reference to neutral position.

    The concept of neutral position adds an unnecessary complication to the discussion of joint range of motion. People just get confused with comparison of a real foot with notions that neutral position of the STJ is "normal" or "ideal" or even better than what position the foot is in. The Root definition of a plantar flexed first ray is also problematic in that it is trying to use a non weight bearing measurement, that may or may not correlate with pathology, to predict pathology.

    A plantar flexed first metatarsal should be defined as a situation where, in stance, or gait, the first and fifth metatarsals bear more weight than average. This is the function that causes pathology. No one has ever shown that when you have a first metatarsal that has 7mm of plantar flexion and 3mm of dorsiflexion relative to the 2nd metatarsal will have higher loads in stance, or gait, will have higher loads than first metatarsal with 5mm up and 5mm down. (no neutral position)

    I will agree that the Root paradigm concept of a partially compensated varus is important. However, that concept can be understood and used without reference to neutral position. It is a foot that in stance will have high loads on the fifth metatarsal and relatively low loads on the first metatarsal with no eversion range of motion available. (No reference to neutral position)

    I will agree that any paradigm of foot function will have to use the terms varus and valgus. It will also have to use the terms metatarsal, calcaneus talus, etc. However, foot function paradigms do not have to use neutral position.

    Those surgeons would understand, and be better able to explain the rationale behind their procedures "to alter forces" if they used free body diagrams and thought about where the foot should be (for reduced loads on particular structures) rather than being concerned about a theoretical ideal neutral position.

    Eric
     
  15. Val:

    Hope you enjoy my articles and the book chapter on Tissue Stress Theory that myself and Eric Fuller coauthored. For you information, there is no one currently lecturing on Root Theory on the international podiatric biomechanics lecture circuit. However, I will be lecturing on Tissue Stress Theory this year in Auckland, New Zealand in March, in Naples, Italy in April and in Helsinki, Finland in October.

    Interestingly, it seems that the only people who currently promote Root Theory consist of one of three groups:

    1. Podiatrists over the age of 60
    2. Lazy podiatrists who are teaching at Podiatric Medical Schools who don't want to change the biomechanics curriculum that they or their predecessors have been using for the past thirty years.
    3. Relatives of Dr. Root

    I would suggest, Val, that you purchase my four Precision Intricast Newsletter books and read all of them cover to cover if you want a better handle on how podiatric biomechanics has changed over the past three decades in regards the transition from Root Theory to Tissue Stress Theory and how you can more effectively use Tissue Stress Theory to improve your therapeutic outcomes with foot orthoses.

    All four of my books may be purchased at the following website:

    http://www.precisionintricast.com/s...anics-English/c/20394513/offset=0&sort=normal

    All four of my books have also been translated as Spanish language editions:

    http://www.precisionintricast.com/s...erior-Español/c/20394512/offset=0&sort=normal

    Good luck with your education.
     
  16. Another tip Val is don't just read stuff written by Podiatrists. Look out to other fields .

    Kevin's books are a brilliant place to start. But while we spend a huge amount of time discussing Root only a small % of custom orthotic devices prescribed daily in the world are made using Root biomechanics
     
  17. Jeff Root

    Jeff Root Well-Known Member

    Valery, tissue stress theory can’t exist without some description of foot structure and the relationship of the osseous segments of the foot. Using the neutral position classification system developed by Merton Root, which provides a more precise definition of forefoot varus and valgus, and rearfoot varus and valgus is the best way to describe structure, structural variation and the relative position of the foot. The foot cannot be in a supinated position or a pronated position unless you have a neutral position to distinguish the supinated foot from the pronated foot.

    Contrary to Dr. Kirby’s assertion, I’m not promoting Root theory and there are no other relatives of Dr. Root involved with biomechanics and podiatry. I’m trying to keep those promoting tissue stress theory accountable and I’m trying to point out their intellectually dishonest tactic of stating that they don’t use Root theory when in fact they do use elements of Root theory in their writing, lectures and practice. For example, if they don’t accept Root’s method of determining the degree of forefoot varus or valgus, or the degree of rearfoot varus or valgus present in the foot, then what method do they use and how do they define these conditions? In the U.S., where podiatry is becoming more and more of a surgical specialty, they depend on Root’s system to assess feet, communicate between surgeons, and to make decisions about surgical procedures.

    Eric, when one assesses the position of the forefoot and determines the presence of forefoot varus, forefoot valgus or a rectus forefoot it is done with the STJ in the neutral position and the MTJ fully pronated. If the position of the STJ is changed then the position of the forefoot changes. As a result of Root’s system clinicians place the foot in the neutral position of the STJ and fully pronate the MTJ to classify the presence of ff varus or ff valgus. This system of convention is similar to placing the palms of the hands facing anteriorly in the standard anatomical positon. If we do not have a standard position for comparing feet then how can we discuss structure or use the terms forefoot varus, forefoot valgus, rearfoot varus or rearfoot valgus? And without Root’s heel bisection how can one determine if the rearfoot is inverted, everted or vertical or if the forefoot is inverted, everted or perpendicular to the rearfoot? You can point to issue of reliability of the bisection technique but the reality is, and the intellectually honest answer is that clinicians use Root’s system to make that determination.
     
  18. Jeff you make some huge assumptions. Which are just not true. I am not going to get in a back and forth.

    But maybe change discussion. If we say the figure 100 represents the pair's of custom orthotics given to patient's in the world on 1 day. How many would you say use Root theory? Put the foot in "neutral" during an assessment etc.

    My guess would be 1 max . If 100 represents the total devices prescribed
     
  19. Except your Dad's system used a non-weightbearing assessment of structure which did not predict the weightbearing and dynamic structural alignments nor compensations (case in point re: this thread) which are required to perform free-body analyses of the structural systems; in that respect Root's non-weightbearing assessment techniques are redundant and worthless.

    Here's my problem with this argument: people such as William Sayle-Creer (who incidently was an orthopaedic surgeon) were using the term "subtaloid joint neutral position", defining feet as "pronated" or "supinated" and using a standardised (weightbearing) technique for assessing for the presence of an inverted forefoot on the rearfoot back before 1944; he described how the foot would compensate for said structural variations which was highly similar to the explanation given much later in Root et al. Vol 2 and provided details of mechanical treatment techniques (which incidentally fall into the realms of a tissue stress approach to management); F.W. Knowles published details of a method of measuring the relationship between a bisection of the heel and a bisection of the distal leg to quantify the amount of rearfoot pronation in 1952; again significantly before the publication of Vol. 1. Knowles also correctly ascertained that the average asymptomatic foot was pronated by around 3 degrees. Much if not all of which was before your Dad even trained as a podiatrist; all of which was before your dad ever wrote on the subject.

    In conclusion: we only need your "Dad's system", if we use your "Dad's system"; personally. I can't remember when I last used your "Dad's system".
     
    Last edited: Feb 6, 2018
  20. drhunt1

    drhunt1 Well-Known Member

    Val-Root Theory was a work in progress. Even Merton admitted to Dr. Phillips that he'd be surprised if what he wrote in those volumes, he'd believe in 5 years. But, instead of furthering his research, adding to what we already know, and utilize the digital formats of testing, Kevin Kirby, among many others here, decided to throw the baby out with the bath water, and devise a "new way of thinking". Balderdash. Just ask any of the TST people what they've resolved. In a word...nada. If you have a difficult time falling asleep one night, just read Kevin's and Eric's chapter on TST sometime....I guarantee restful sleep.

    As an example, just this past year, I attended a Podiatry seminar in Livermore where Kevin was lecturing. He claimed that the triceps surae muscle could either supinate or pronate the STJ. Say what? I looked around the room at the starry-eyed residents to witness their reaction...it wasn't pretty. While it may be possible for the triceps surae muscles to pronate the foot...does anyone reading my post have any idea how "flat" that foot would have to be in order for this to occur? More balderdash. Kevin, and his ilk, IMHO, need to be called out on their outrageous claims and grandiose "ideas". Besides...there's really nothing new about TST...it is just an attempt to design a better mousetrap. Hope this helps.
     
  21. All about axial position in relation to the insertions. Not really that hard to understand
     
  22. drhunt1

    drhunt1 Well-Known Member

    Mike...please...what is the MAIN reason the triceps surae exist...and why does it fire when it does? And seriously...we're not talking theory...but using the info we have and applying it DIRECTLY to patients. How "flat" would the foot have to be in order for the triceps surae muscles to PRONATE the STJ? Are you insinuating that you would not be able to discern this with watching the patient ambulate or assessing them WB?
     
    Last edited: Feb 6, 2018
  23. U
    You seem to be frothing again.

    The problem is are you talking for the general population or someone with a very medial deviation STJ axis or lateral.

    Generally main purpose is to absorb energy and return it through a catapult like system, which will cause an plantatflexion moment around the ankle joint axis.

    3 moments can occur around the STJ axis depending at the axial position pronation, supination or of course nothing all depending where the line of forces in relation to the axis.

    Just because something is rare it doesn't mean it doesn't occur and perhaps Kevin was using that to make a point ( you would to ask him)
     
  24. efuller

    efuller MVP

    Jeff, how can one tell if a foot is pronated or supinated if there are more than 2 different definitions of neutral position. Even more importantly what should one do if you determine that a foot stands in a pronated position? What should one if one sees a foot that is in a pronated position and has lateral ankle instability? Yes, neutral position was used as reference position to differentiate one foot type from another. So, lets go back to the reasoning of why this position was chosen. Why should this position be used as a reference point? Or, can we treat the foot without using this paradigm of foot classification. If you look at the protocol that Root gave for prescription writing you could make the case that he did not use the classification protocol. He used what worked. So, if NCSP is 4 degrees inverted why do you balance to vertical? Because it works (most of the time). Not because it addresses the theory used in the foot classification.


    I don't think we ever made the claim that we don't use some elements of Root theory. I use an intrinsic forefoot valgus post in my orthotics all the time. However, the measurements that I make to decide on whether to use an intrinsic forefoot valgus post are quite different from Root theory. I use the standing maximum eversion height measurement to determine how much intrinsic forefoot valgus post to use. I derived this measure from thinking logically on what the Root paradigm should be doing if they followed their own theoretical logic. (The prescription writing logic: Don't evert the foot farther than it can go. So how do you know how far the foot can evert using a forefoot to rearfoot measurement done in neutral position and you are looking at a foot that in stance is at the end of range of motion of pronation of the STJ. We both agree that the forefoot to rearfoot relationship will be different from STJ neutral to STJ maximally pronated. ) So, the maximum eversion height measurement does not need neutral position. So yes, I am using a Root concept, but not in the way that he intended. However, I am not using neutral position. If I am not using neutral position, am I doing something different than Root theory?

    The difference is that tissue stress does not need to classify whether or not a foot has a forefoot varus or valgus. Tissue stress needs to decide whether or not treatment of a patient's problem would benefit from a varus or valgus wedge. Root theory adds in an extra confusing layer with the inaccurate neutral position measurements. I don't think these measurements can consistently help a clinician decide whether or not to add wedging to a prescription. In addition to the heel bisection there is the inherent inaccuracy in the forefoot to reafoot measurement caused by letting the medial column float when taking the measurement. At one of the John Weed memorial lectures I had several attendees measure the same foot and there was a ten degree range in what people found in forefoot to rearfoot angle using the same heel bisection.

    Eric
     
  25. Jeff Root

    Jeff Root Well-Known Member

    The lectures I was referring to were given by Gavin Ripp, DPM, a young and bright podiatric surgeon who practices just 11 miles from Dr. Kirby's office.
    http://www.mcdowellpodiatry.com/bio/dr-gavin-ripp-podiatrist.cfm
     
  26. Jeff, was this IFAF meeting in question on a cruise ship or in Vegas as they usually are? That one individual getting paid to deliver a lecture while simultaneously getting a tan supports your Dad: that doesn't make for good scientific argument, as well you know. That he works near to Kevin is neither here nor there; should I throw in that he doesn't appear to have been outside of the USA as part of his education? You know, in your heart of hearts, that your scientific argument game is better than that, Jeff- come on! Can you list this fella's publications on the subject of podiatric biomechanics- perhaps that'll give us all a better insight into his background?
    Maybe Kevin should have added another category to his list?
    4) The unquestioning students of the lazy podiatrists who are teaching at Podiatric Medical Schools who don't want to change the biomechanics curriculum that they or their predecessors have been using for the past thirty years.

    And the beat goes on... which would suit all of those with their vested interests in "Root", right, Jeff? It's over, your game is old... move along, move along.
     
  27. Nice. Nicking that.
     
  28. efuller

    efuller MVP

    Matt, You do know that in Normal and Abnormal function of the foot it says that equinus (tension in the Achilles tendon contraction of triceps surae) causes pronation.
     
  29. Funny. Matt. you do know that the pronation compensation for equinus was described well before Root even trained as a podiatrist... Bless your cotton gusset.
     
    Last edited: Feb 6, 2018
  30. efuller

    efuller MVP

    If you look in the index of Normal and Abnormal function of the foot under equinus you will see that in one part of the book there is a section on equinus causing supination and another part of the book discussing how equinus causes pronation. Kevin was not the first to think this.

    Matt, can you explain what flatness of the foot has to do with the ability of the triceps to cause pronation of the STJ.

    I have explained how an equinus could cause pronation in one foot and supination in another foot in a short paper titled the equinus paradox. Matt, if you are interested I could repeat it here. The explanation uses simple terms like center of pressure and joint moment. We are building a better mousetrap.

    Eric
     
  31. Jeff Root

    Jeff Root Well-Known Member

    Simon, the conference was in Lake Tahoe, a two hour drive from his home. I had never met Dr. Ripp before. He had no conflict of interest to disclose and he was not there to promote any surgical product, book sales, etc. He presented a number of cases and explained his rational for the type of surgery he preformed. He presented cases with good and poor outcomes so that the attendees could learn from his surgical successes and failures. He never mentioned Merton Root, Root Theory or Tissue Stress Theory. His descriptions of the foot were based on Root's definition of conditions such as forefoot valgus and rearfoot varus. In other words, when he used these terms the audience assumed he was using the classic Root based definitions. Much of the lecture was radiographically based with before and after radiographs of the procedures. Podiatry in the U.S. is much different because it far more surgically oriented than it is in many other countries. For example, there were several lectures about dermatology, biopsy and the life or death outcomes that resulted from management of these cases. The osseous surgery cases that were presented required a common definition of the terminology utilized to describe the structure and function of the foot. If you're going to do an osteotomy of the 1st met or the calcaneus, you better know what position the bone is in and how and why you plan to reposition it. Dr. Ripp is a great example of skilled U.S. podiatrist who relies on Root's work as a part of his foundation for making treatment decisions.
     
  32. drhunt1

    drhunt1 Well-Known Member

    Yes...as COMPENSATION for an equinus deformity, (abnormal), I would imagine that pronation is required...if for no other reason, than to get the hallux against the ground and keep it there through propulsive phase of gait. You asked me about "flatness" of the foot. I've stated this before, and will do it again...we have a definitional problem in re to structure. The person who comes into a Podiatrist's office that has such a "flat" foot, (not discussing angle of dorsiflexion of the calcaneus), that the triceps surae muscle actually pronates the foot during midstance and propulsion, would be So broken down on the medial aspect, that they should present with PTTD, a talar head that nearly contacts the supporting surface, etc...all the signs of a pronated foot. During swing phase of gait, it is hard to imagine that the triceps surae muscles could pronate the STJ. No...keep your paper...it is probably as boring as your chapter in Lower Extremity Biomechanics. You are NOT building a better mousetrap...you live in an echo chamber with other TST adherents. Now...can you answer the following: What biomechanical anomaly that we face on a daily basis has the TST resolved? (And, please...don't give me the BS about ALL anomalies, ie., bunions, hammertoes, etc).
     
  33. drhunt1

    drhunt1 Well-Known Member

    What's your point? I mean, Kevin stole his medial skive technique from someone else who wrote about it in 1979...all of you TST adherents stole your "idea" from McPoil, lateral extensions on orthotics was written by an orthopedic surgeon, but has since been discarded by the ortho community, even though Kevin and Paul Scherer still believe it's true. Are you looking for validation?
     
  34. drhunt1

    drhunt1 Well-Known Member

    I'm sorry that I appear rather "frothy"...but I'm just treating others as I have been treated here.

    That being written...if you and I can't agree on the function of the triceps surae muscles, then the argument cannot move forward. I have NO desire to drive a round peg into a square hole. Nor should you. You have a private practice and, therefore, can treat your patients any way you feel comfortable. Good luck.
     
  35. drhunt1

    drhunt1 Well-Known Member

    Thanks for the reply. Many here are not Podiatric surgeons, therefore do not take this into account.
     
  36. I really like that one also, Eric.

    Here is a corollary:

    "The difference is that tissue stress does not need to classify "foot deformities" or "subtalar joint neutral" in order to properly treat the patient with orthoses. Tissue stress needs to simply decide what the injury is and then decide how best to reduce stress on that injury."
     
    Last edited: Feb 7, 2018
  37. efuller

    efuller MVP

    Matt, you said you read the chapter. In the chapter we explained plantar fasciitis, hallux limitus and hallux valgus, posterior tibial dysfunction. In the Podiatry Today feature that came out this month I set forth a prescription writing protocol to "resolve" those issues. You can't that we have not addressed those issues. You can disagree with logic put forward. But to say that we have not addressed the issue is just wrong. I'm waiting for you to come up with a better criticism than we used arrows or it's boring.
     
  38. Trevor Prior

    Trevor Prior Active Member

    There is a great sense of de ja vu here in the thread but...

    I was interested in the comments regarding the surgery and the aims of correcting foot position. Root et al, certainly helped to classify alignment of the foot in terms of forefoot to rearfoot position (albeit unreliable to measure), 1st ray position and, as Eric noted, partially compensated varus etc.

    These alignments are relevant to the Podiatric Surgeon because the aim of surgery is to place the foot plantigrade - there is a common term that we use which states ' thou shalt not varus' when correcting foot position with osteotomies and fusions. A varus foot is now at best a partially compensated foot type or uncompensated. Indeed, with STJ fusions, the heel is better in slight eversion or valgus.

    So, the terms described in the Root et al paradigm are useful and commonly used BUT this does not apply the neutral position concept as the foot is designed to function plantigrade or, in Root et al terms, in a compensated position as it would be pronated in relation to STJ neutral.

    Indeed, Podiatric Surgeons will discuss the plane of deformity to try and determine the best combination of operations to perform to achieve the plantigrade position. Given that these are based on static x-rays it is actually the plane of compensation that is assessed but that is another discussion.

    So, to my mind, the concepts are not mutually exclusive in so far as we can quite happily use the classification outlined by Root et al and have an idea as to how a foot may respond to the forces placed on it during activity. However, the response to that force will vary from individual to individual and, what evidence we do have, informs us that the foot does not function around neutral. So, we then determine what is required for the presenting complaint and at times, this will marry the orthoses choices that would be consistent with the Root paradigm, at others not and other techniques (e.g. skive) may be required to achieve the desired affect.

    Surgery does not place the foot to STJ neutral (indeed this would be a disaster) and orthoses do not facilitate the foot functioning around neutral, yet both achieve positive outcomes and this is because they alter the forces acting on the tissues. Future research really needs to start evaluating this further as, for instance, we achieve better surgical results by realigning the kinematic position to influence the kinetics. I suspect we do alter the relative position of the STJ and MTJ axes dynamically and alter the relative motions of the joints of the foot in relation to one another. Trying to predict potential complications following such realignment can be a challenge and the affect of proximal dysfunction can be 'missed'. Achieving similar changes is much more difficult with orthoses although intuitively, not an impossibility to have some alteration of the kinematics.

    It is a shame in some ways that we use the term tissue stress as any paradigm that attempts to treat a condition is essentially aiming to reduce tissue stress - thus the Root et al paradigm could be described as a tissue stress approach. It is just the method by which it is achieved and the validation or lack of validation of the particular concept.

    Anyway, I am off later to-day to present a two day course on clinical diagnosis current concepts in podiatric biomechaincs, it is always interesting to see the current concepts being employed by colleagues and how to develop their practice in a constructive way.
     
  39. Griff

    Griff Moderator

    1. These are not conditions. They are terms used based upon observations.

    2. If you dig a bit deeper into the Orthopaedic literature you’ll find there is reference to these sort of terms being used loooong before 1971...
     
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