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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. Jeff Root

    Jeff Root Well-Known Member

    Eric, I really don't care what "theory" the practitioner uses. It is my job to manufacture the orthosis according to there prescription specifications. As a result, my client could be practicing the Root approach or the TST approach and I might never know unless it came up in a consultation. I don't believe one can look at at a finished orthosis and know what theory the prescribing practitioner subscribes to. Root Lab continues to evolve in terms of technology and orthotic design. We provide what the market demands of us. So it is the customer who determines what products we manufacture through demand and what theory drives their prescriptions. What is important is that I have the ability to communicate with my customer and that they have the ability to communicate with me. That's why proper terminology is so critical!
  2. drhunt1

    drhunt1 Well-Known Member

    "Slowly I turned...inch by inch, step by step...".

    Anyone whom regards Simon Spooner with anything but contempt on this blog, should really question his sanity...and their own. Really, Simon? Attacking Jeff because he was a firefighter? That's worse than you attacking me because I shoot birds, (before you put me on ignore). No matter...the word will get back to poor Simon. And I was a firefighter for the USFS for two summers, before I graduated with a WFB major...so what's your point? Nothing....nada...zilch. Jeff Root does see patients...and has learned a lot along the way...I can attest to that. Look...we've all seen your poor excuse of an orthotic, Simon...pathetic, at best. Next thing I expect to read from the TST adherents, is that nothing matters...no measurements, no corrections, no compensation...throw it all away. Kevin Kirby wrote that he believes practitioners are lazy. Really? It's amazing that every time I read one of Kevin's "contributions" in Podiatry Today, I am more interested in the replies that bury his hypothesis. To my knowledge, besides Eric Fuller and Kirby, NO ONE here in the States is teaching TST. There's a good reason why.

    Attached Files:

  3. efuller

    efuller MVP

    Daryl, some interesting questions.

    It seems that you are saying casting position does not matter. I agree. The device just needs features that will reduce forces in the first metatarsal phalangeal joint.

    It depends on how much forefoot eversion there is in the maximally pronated position. This is something you cannot know from the classic Root measurements because the forefoot to rearfoot angle changes from neutral position to the maximally pronated position. Looking at the heel bisection is less helpful than looking at the maximum eversion height measurement. Daryl I mentioned this measurement to you before and you did not comment on it.

    A. Why do you care if the patient is standing pronated, neutral or supinated?

    B. You use the maximum eversion height measurement, or the coleman block test. You don't need to use any measurements related to neutral position.

    Maximum eversion height measurement. You need a forefoot valgus wedge when you want to reduce tension in the plantar fascia and there is eversion range of motion avialable. Daryl, you should check out the article I wrote for this month's podiatry today on prescription writing with the tissue stress paradigm.

    How can you say if a foot is in pronated or supinated position if there are 3 (or more) different definitions of neutral position and they don't all refer to the same joint position?

    There are some muscles that are strongest at the joints end of range of motion and there are some that are strongest in the middle of their joints range of motion.

    The static measurement of the location of the projection of the STJ axis onto the transverse plane is a good measurment that can predict some physical observations.

    Daryl, what do you, with an orthotic, with someone who complains of lateral ankle instability, has a laterally deviated STJ axis, a perpendicular forefoot to rearfoot and stands 3 degrees from maximal pronation and 6 degrees pronated from neutral position? Is your goal to push this person towards neutral position?

  4. efuller

    efuller MVP

    Still waiting for a critique other than it bores you, we used arrows and it's too complicated. I had many students tell me what I taught was easier to understand than neutral position biomechanics. I'm sorry that reality bores you. If you want to contribute to the conversation you can tell us what we got wrong.
  5. drhunt1

    drhunt1 Well-Known Member

    Oh, weren't those arrows helpful? And weren't those drawings professional grade? Sorry...I wasn't impressed.

    You wrote: "Daryl(sic?), what do you, with an orthotic, with someone who complains of lateral ankle instability, has a laterally deviated STJ axis, a perpendicular forefoot to rearfoot and stands 3 degrees from maximal pronation and 6 degrees pronated from neutral position? Is your goal to push this person towards neutral position?"

    The answer is yes. But your example doesn't make sense. These patients are at the end of their ROM, (in other words, there are NOT 3 degrees from maximal pronation), if they truly are complaining of lateral instability. 3 degrees from maximum pronation is enough for the peroneals to compensate and absorb the deforming force(s).
  6. Eric,
    I have to jump in here as I do have some expertise in this subject area of "lateral" or chronic ankle instability.
    A long held practice of everting the hindfoot and ankle to end range of motion with bracing or foot orthoses is actually the worst thing you can do to the active athlete with an unstable ankle. While this fits with reducing tissue stress on the lateral ankle ligament complex, it significantly compromises proprioception in the subtalar joint. When range of motion is available in the subtalar joint there is enhanced proprioception from the mechanoreceptors to activate the peroneal reflex. Providing available range of motion to the subtalar joint allows this joint to move during a perturbation before the ankle is forced into inversion. This dampening mechanism delays loading of the lateral ankle ligaments, giving time for the peroneals and other postural mechanisms to engage. Yes, the optimal position of the subtalar joint in a patient with chronic ankle instability is neutral !!!
  7. rdp1210

    rdp1210 Active Member

    Come on Eric! -- you're trying to say that my 1983 paper didn't add anything? Of course I measure the FF to RF relationship with the STJ neutral and with the STJ maximally pronated. I have advocated doing that for the past 35 years. So you're going to beat up Mert Root because he only did one measurement. In fact we need the instrumentation to take a lot more measurements that just those two. We need to measure the total ROM of the midtarsal joint around all three cardinal axes in both directions with the subtalar joint in neutral and with it in maximal pronated position. In fact we need to construct a 3D graph showing the range of motion of the midtarsal joint (similar to the 2D ones I did for Albert's book) so you can start predicting what the foot will do distal to the midtarsal joint, and also to fully understand how the rearfoot is affected by the forefoot. Mert got the ball rolling with trying to quantitate forefoot to rearfoot relationships. He didn't finish the job. However we have the likes of Jarvis that makes no attempt to quantitate forefoot to rearfoot relationship, but uses only a visual dichotomous methodology. Certainly a step back to the pre-Root days. There have been a multitude of papers proposing various tools and methods to describe forefoot to rearfoot. If Jarvis wanted to discredit Root, she could have at least used a Root tool to take a measurement. By the way, Perkins utilized the term forefoot varus in 1948 (before Mert graduated from school) and described how to correct it surgically.

    Again, Eric - are you interested in making foot biomechanics a real science where predictions can be made? Does a person standing with the subtalar joint maximally pronated ever develop peroneal brevis tendinitis? I’ve never seen a person with a partially compensated rearfoot varus develop peroneal tendinitis, have you? (BTW – if you don’t remember, a partially compensated rearfoot varus is defined as a condition in which the person stands in static stance with the subtalar joint maximally pronated but the calcaneus is still inverted from the perpendicular.)
    If you're not taking measurements, you haven't got a science. How do you know if things are changing if you have no numbers? Your tissue stress concept is only a trial-and-error technique base purely on subjective data, and you will never get to the point that you can predict risk with only subjective data. Also a vast majority of my patients are neuropathic. They don’t feel the stress on their tissues.

    Duh – do you measure your Coleman Block? Wouldn’t that be a form of measurement? How many Coleman Blocks do you own? Is it a trial and error? Again, I'm not defending Mert Root, I'm defending real science – which requires numbers!

    Ok – you point out an interesting question that we as a profession need to come to a final agreement on. However the fact that there have been different descriptions of where the neutral position is does not negate the need to have one. I asked Kirby 2 years ago in Vancouver to comment on the actual need for one, but he waffled and never gave a real answer. You’ll remember that Henderson, Wright & Desai defined their STJ neutral position as a position when the heel is perpendicular. Problem with that definition is that it makes it possible for many people to have no range of pronation available, but they will still have strain on the medial not the lateral side of the foot. However for you to run away from neutral position, doesn’t make us any more intelligent or scientific. I guess you can argue that the Greeks did mathematics without the number zero. A great Feat indeed. However, how much more can mathematicians do with the number zero. It opens up the negative infinity of the number line and gives us the possibility of trigonometry and calculus (try doing those without the number zero). Right now clinical biomechanics is still in the medieval ages, however tissue stress alone is not the path to the Renaissance.

    Please give me the names of the muscles that are strongest at their shortest or longest length. Such would be against every known muscle biomechanics concept I've ever read. How can a muscle get longer or shorter when the joints they cross are at their end range of motion.

    Have I ever argued that point? Please reread my 1992 Stickel Award paper. Of course I put the STJ axis into my biomechanical examination! It’s PART of the total picture. It is not the WHOLE picture! Not only that, by measuring the transverse plane motion in the subtalar joint, you can also predict the movement of the STJ axis against the bottom of the foot. I take lots of measurements that Root didn’t take. Does that make Root wrong? Of course not. As I said – and I’m getting tired of saying this over and over – just because Root didn’t describe everything, doesn’t make him wrong about everything he did describe. Aren’t you glad that he handed to future generations further refinements to make of his ideas and also the opportunity to add new ideas? The only reason for anyone to rubbish the Root name is because they see the only way to build their own statue is to tear down his. I expect to make many more contributions to the understanding of biomechanics and its predictive powers. This arena is really a waste of time, just think of how much real research could have been done by those who contribute greatly here. There isn’t one ounce of research coming out of this arena. So to all of you who write the most posts – get a life of productivity to help us all know more! I contribute very little here because I’ve got too many diabetic foot ulcers to care for and try to figure out how to prevent. I'll look forward to see your research poster at I-FAB, Eric. And if you really want to turn your tissue stress ideas into action – get involved with diabetic biomechanics.

    You didn’t give me any additional information, so that question is unanswerable. What is the total rearfoot varus? What is the RCSP and the NCSP? What is the forefoot to rearfoot relationship when the STJ is neutral and with the STJ fully pronated? What is the FF-RF relationship when the forefoot is maximally supinated in the frontal plane with the STJ neutral and with the STJ pronated? What is the lateral/medial translation of the os calcis in RCSP and NCSP? (or did you read that part of my 1992 paper?) You’re asking ridiculous questions because you don’t want to admit that tissue stress without Root is as bad as only doing 7 (or in the case of Jarvis 5) Root measurements. You’re really cheating the patients by not loading up your tool belt with all the tools in the closet.
  8. efuller

    efuller MVP

    Hi Doug, good to see you contributing here on podiatiry arena.

    In the chapter that Kevin and I wrote on tissue stress we discussed several different causes of lateral ankle instability. One type was a foot that functions maximally pronated with sinus tarsi syndrome and has inhibition of the peroneal muscles and will have an increased peroneal reaction time. For this foot, I agree that adding additional pronation moment would be a bad thing. These feet often have a maximum eversion height of zero and when you see that you would not add a forefoot valgus wedge.

    Another kind of lateral ankle instability comes from a laterally deviated STJ axis. It's possible to have both. In Root theory you might call this the rigid forefoot valgus foot. This foot will often have eversion range of motion

    The lateral ligaments do not come under stress until the STJ is at the end of range of motion in the direction of supination. You need to think about ankle sprains in terms of STJ moments and accelerations. The ankle sprain will not occur unless there is a supination moment that starts the motion in the direction of supination. This occurs when there is an unexpected variation in the surface that moves the center of pressure medial to the STJ axis. Feet with a laterally deviated STJ axis will have to invert less far than a foot with an average location of the STJ axis before the entire foot will be on the medial side of the axis. At this point all ground reaction force is causing a supination moment and the STJ will supinate until something stops it (peroneal muscles or collateral ligaments). So in normal activity, the valgus wedge does not reduce stress on the collateral ligaments. The increased pronation moment, from the valgus wedge, will decrease the liklihood that the supination moment will start. It important to evaluate the position of the STJ axis before adding wedging affecting the STJ.

    Moving the STJ toward neutral position is adding a supination moment and pushing the foot toward an ankle sprain. A "perturbation" will have a direction. Some perturbations (changing the moments acting around the STJ) will tend to push the STJ toward pronation and others will shift towards supination. When the STJ is say 2 degrees from maximally pronated a pronation moment will move it toward maximal pronation. A perturbation that causes an increase in supination moment will tend move the STJ towards supination both when the STJ is 2 degrees from maximally pronated and when it is maximally pronated. What is this damping mechanism that you are talking about?

  9. Eric,
    Regardless of what you speculate in your chapter, there are no credible peer reviewed studies showing that a "laterally deviated" subtalar joint axis is a risk factor for an ankle sprain. Your description above ignores the components of neuromuscular control over the ankle which is far more important in chronic ankle instability than a slight variation of the subtalar joint axis. Pronating the subtalar joint to end range of motion to "relieve stress" on the lateral ligaments compromises this mechanism. Furthermore, your description of the kinematics of a typical ankle sprain is incorrect. It appears that your strategy with wedging is based on an assumption that the ankle sprain is primarily a frontal plane event.
    We now know that the primary motion is in the transverse plane dominated by external rotation of the tibia. It is this motion which causes rupture of the anterior talofibular ligament. Prevention of the ankle sprain is far more complicated than "relieving tissue stress" with a valgus wedge and before advocating that strategy, you need to understand the mechanism of the ankle sprain. For further reading:

    Richie DH. Functional Instability of the Ankle and the Role of Neuromuscular Control
    A Comprehensive Review. Journal Foot and Ankle Surgery, 40:240-251, July/August 2001

    Richie DH. Effects of Foot Orthoses in the Treatment of Chronic Ankle Instability. Journal of the American Podiatric Medical Association 97 (1): 19-30, 2007.

    Kaminski TW, Hertel J, Amendola N, Docherty CL, Dolan MG, Hopkins JT, Nussbaum E, Poppy W, Richie D; National Athletic Trainers' Association. National Athletic Trainers' Association position statement: conservative management and prevention of ankle sprains in athletes. J Athl Train. 2013 Jul-Aug;48(4):528-45.
  10. efuller

    efuller MVP

    In my comment I was using the information from your paper where you measured MTJ eversion in pronated, neutral and supinated positions. We both should do more to get the word out that Mert's work is incomplete.

    Daryl, the palpation of STJ axis technique has been shown to be repeatable. This has not been shown for forefoot to rearfoot measurement. You can do science with categories as opposed to precise measurements. You can group STJ axis positions by medially deviated, average and laterally deviated. Daryl, you should come up with a modification of the definition of forefoot to rearfoot measurement that tells you where to put the medial side of the MTJ. (There is no anatomical structure that guides the longitudinal midtarsal joint axis. The cc joint can plantar flex and dorsiflex and the TN joint can platnar flex and dorsiflex. With the existing definition, the forefoot to rearfoot measurement will be un repeatable because of variation in position of the medial side of the MTJ. ) As you point out we can't do science without accurate measurements.

    Daryl, the maximum eversion height is something you can put a number to. It is the height off of the ground of the plantar surface fifth metatarsal head when the subject is attempting to evert their foot foot with their peroneal muscles. This is a direct observation that is not muddied by trying to cacalulate this number from multiple other measurements.

    Daryl when we were debating at ACFOAM I asked you why neutral. You said why not? When you read about Root's development of neutral position he said we need a reference point that we can use to compare feet. However, I don't recall ever seeing a reason why the biophysical criterea for normalcy should have the STJ rest in neutral positon. Daryl I'm asking you why you think neutral position is the path to the renaissance. Why do we need to compare a foot to an idealized normal to figure out why a particular foot has pathology.

    I'm going to try to explain one more time why the zero analogy doesn't hold water with neutral position's circular definition. We come upon a stick with 12 equally spaced marks and we decide that 4th mark from the end is neutral and equal to zero. Every mark to the left is pronated and every mark to the right is supinated. Another person comes along and decides the 6th mark is zero/ neutral. Every mark to the right of the sixth mark is pronated and every mark to the left is supinated. The choice of which mark is zero/ neutral is arbitrary. If you decide one day that 1/3 of the range of motion of the STJ is neutral and then on another day you decide that the curvature of above and below the lateral maleolus determines meutral. On yet a third day you choose the "dell" in the arc of motion is neutral position. How can we say we are being scientific if we have three competing definitions of an arbitrary point in the range of motion of the STJ.

    Soleus. It needs to be very strong at max dorsiflexion of the ankle.

    Daryl, you are going to far here. I have given a list of Root ideas that I use. I am not saying that he was wrong about everything. I am saying that clinging to comparison of an idealized normal is limiting future progress. You all keep saying that he expected his ideas to be criticized. Criticizing his ideas is not trashing his name.

  11. efuller

    efuller MVP

    Doug, you should reread my post. I did mention the peroneals which would be part of neuromuscular control of the ankle joint.

    Your comment about a slight variation in position of the STJ axis. One study had around a 40 degree variation in position of the projection of the STJ axis in the transverse plane. I would not consider that slight.

    I did not say that pronating the STJ is to relieve stress on the collateral ligaments. What I said was that it would reduce the liklihood of unexpected STJ supination. Supination is a tri plane motion that includes talar and tibial external rotation relative to the calcaneus. What do you mean when you said that the primary motion in an ankle sprain is external rotation. Are you saying that this external rotation occurs without STJ supination? How does the center of pressure of ground reaction force get medial enough to be able create a large enough internal rotation moment on the talus. (We are talking about relative motion of the talus and tibia right?)

    Also how does the calcaneofibular ligament tear without STJ supination.

    What damping mechanism? What definition of damping mechanism are you using?
    Do you have literature showing that optimal position for ankle instability is neutral. How often do you do a bioeval and look at NCSP? The vast majority of individuals will have their medial column off of the ground when in STJ neutral. Do you think that an orthotic made from a cast taken in STJ neutral will put the STJ in neutral?

  12. Eric,
    I did read your post carefully. You describe two conditions which can cause chronic ankle instability. I pointed out the fallacy and lack of any study validating the second condition you describe. I continue to warn about pronating the subtalar joint to "reduce the liklihood of unexpected STJ supination". I just read Daryl's previous post and he is spot on about the dysfunction of joints which are forced to function at end range of motion. Studies show this compromises proprioception. Secondly, pronating the subtalar joint to end range pronation will reduce tension on the peroneals and potentially compromise the tendon stretch reflex. Current interventions to treat the athlete with chronic ankle instability focus on all aspects of neuromuscular control over the ankle joint complex. Valgus posting of foot orthoses have not shown any benefit for these patients and there are certainly no studies to validate any of your strategies to treat chronic ankle instability.
  13. Jeff Root

    Jeff Root Well-Known Member

    Mike, from the abstract:
    "RESULTS: In ankle-foot neutral position, the contact area of STJ was (2.79 +/- 0.24) cm(2). In the range of motion of adduction-abduction (ADD-ABD), the maximum contact area was (3.00 +/- 0.26) cm(2) when the foot was positioned 10 degrees of ABD (F = 221.361, P < 0.05). In the range of motion of dorsiflexion-plantarflexion (DF-PF), the maximum contact area was (3.61 +/- 0.25) cm(2) when the foot was positioned 20 degrees of DF (F = 121.067, P < 0.05). In the range of motion of inversion-eversion (INV-EV), the maximum contact area was (3.14 +/- 0.26) cm(2) when the foot was positioned 10 degrees of EV (F = 256.252, P < 0.05).
    CONCLUSIONS: Joints, such as STJ, therefore, are not necessarily in neutral position when the ankle-foot is placed in the traditional concept of neutral position. The results demonstrate that the most approximate STJ neutral position was in the foot position of 10 degrees of abduction, 20 degrees of dorsiflexion and 10 degrees of eversion".

    Mike, what reference did they use to determine that the entire foot was abducted, dorsiflexed and everted? Of particular interest to me is what anatomical structure or structures did they use to determine that the foot was everted? In order to state that the foot is everted you need to have a reference. What was the reference in this study?
  14. Jeff Root

    Jeff Root Well-Known Member

    Mike, after you answer my previous question then I have one more question. This study was conducted on amputated specimens. Since it is impossible to perform the study technique on living subjects, how does this study help us to find the neutral position clinically?
  15. All here Jeff

    Attached Files:

  16. It doesn't help us find neutral most likely and that's the point. If Roots STJ neutral is not real neutral then it shows we don't need neutral
  17. rdp1210

    rdp1210 Active Member

    Sorry, Mike. That is not logical conclusion. If the calcaneus is 5 degrees inverted to the leg, is the peroneus brevis stretched from it's resting length? (assume ankle at 90 degrees). Is it stretched to it's maximum length? Joint position is essential to know when discussing muscle function, both active contraction strength and passive tension. Like I said, we may need to have a conclave to get everyone on the same page as to what the STJ neutral position is, but to say we don't even need one is a mistake of grave consequences in the ability to communicate and prescribe as well as to try to figure out consequences. Is Root comprehensive of all biomechanical knowledge needed -- of course not -- I've never practiced nor preached such. Is it part of the total knowledge needed -- absolutely. Is there a lot more to know - 100% yes.
  18. We might need a conclave sure. :) imho Subtalar joint axis (average/bundle) position is a much better point of reference to be using .

    Has anyone got a study showing talar-calcaneal position in Root neutral?
  19. Jeff Root

    Jeff Root Well-Known Member

    Mike, thanks for the article. Please read it and tell me what anatomical structure, landmark or reference they used to determine the frontal plane position of the foot in order to determine whether the foot was inverted or everted?

    The author's state" In 1977, Root et al published a textbook containing a theory about the STJ neutral position. Root described subtalar joint neutral as the position in which the forefoot is locked on the rearfoot when the midtarsal joint is maximally pronated". Wrong, wrong, WRONG! Mike, this is blatantly wrong!!!!!!!!!!! How can a peer reviewed article be so totally wrong?
    The position of the MTJ has absolutely nothing to do with the position of the STJ. When the STJ is in the neutral position the MTJ can be supinated or pronated. In addition, the MTJ can be fully pronated throughout the entire range of motion of the STJ. The authors don't even know how Root defined the neutral position. Root defined the neutral position of the STJ as that point at which the STJ is neither supinated or pronated. He then went on to describe techniques to help the clinician determine when the STJ was in the neutral position.

    One criticism I have of Root et al's work is their description of supination and pronation of the MTJ. For example, one of their descriptions of closed chain motion of the STJ and MTJ during closed chain STJ pronation was described as rearfoot adduction and plantarflexion (which is relative abduction and dorsiflexion of the forefoot) and simultaneous rearfoot eversion (relative inversion of the forefoot). They said that the MTJ was pronating about the oblique axis and supinating about the longitudinal axis. While the combined motion of the forefoot abduction, dorsiflexion and inversion of the forefoot relative to the rearfoot at the MTJ is in fact triplane motion, it is not true supination or pronation. In fact, we do not have a term to describe this form of triplane motion at a joint. We can only describe the motion of the segments relative to the cardinal body planes and relative to each other. So it is really a misnomer to say that the MTJ is supinating about one axis and simultaneously pronating about another axis because these are conflicting motions. But I assume because it is so cumbersome to to describe the exact motion of the segments every time, they used supination and pronation relative to the long and oblique axis to describe MTJ motion.

    Edited addition to my comments: Note that the authors didn't even provide a reference to Root's book Biomechanical Examination of the Foot in which on page 54 he defined the neutral position of the STJ as "The point at which the foot is neither supinated nor pronated".
  20. scotfoot

    scotfoot Well-Known Member

    Hi Doug,
    With regard to the text below I would like to echo Eric's question . What do you mean by "dampening mechanism" ?

    Doug said -
    "Providing available range of motion to the subtalar joint allows this joint to move during a perturbation before the ankle is forced into inversion. This dampening mechanism delays loading of the lateral ankle ligaments, giving time for the peroneals and other postural mechanisms to engage. Yes, the optimal position of the subtalar joint in a patient with chronic ankle instability is neutral !!!"
    Eric then asked -
    "What damping mechanism? What definition of damping mechanism are you using?"

  21. Never mind that bollocks; how can the "forefoot be locked on the rearfoot", that's where my concern would lie..? Basic biomechanics and you can quote me on this: "joints do not lock, thus the forefoot does not "lock against the rearfoot"; Viz. there is no "locking point of the midtarsal joint" especially when no input force is quantifed- right Daryl? Child-like language from a bunch of non-scientifics. "Maximally pronated about the oblique mid-tarsal axis"- What? Really? But ya' know.. just as goon like, but thinking they know the score... err, no... Search podiatry arena, see how many times you can find Jeff or Daryl referring to the midtarsal joint as "locked"... many. But once again, now black truly is white as Jeff attempts to turn an argument that has been put to him countless times and forge it as his own. Seriously WTF. Same shitty arguments put out again and again, but now you've suddenly changed sides, Jeff?. It's not a rollercoaster, it's a crashing aeroplane and these individuals will not change their positions even in the light of that certain truth when the plane hits the ground or the tower, whichever comes first. Mike, take it from me, you are wasting your time; 20 years and absolutely no movement on their thinking. Arabia, Arabia, Arabia, Arabia 20 years, all the papers published, the conference presentations, the social media debates... not an inch of movement on Jeff Root nor Robert Daryl Phillips stance during that time, not an inch. Good luck. You could perform pure alchemy and they'd still claim that Root's "gold" was better.

    "Flight leader, this is "Combat" your forward end controller
    I have three targets for you
    Your first target is a blockhouse, target number 11 at the north-east corner of the combat zone, request: Napalm
    Rodger, flight leader, the identity of your request is, eh, batch of Napalm on the blockhouse in the north-east corner of the target area
    Flight leader, understand, 30 seconds
    White flag, this is "Combat", we have you in sight
    Roll on to the west, call to confirm you have target area, a'ight"

    6 o'clock in the morning & i'm the last person in this plane
    Still awake
    Y'know I can almost smell the blood washing against the shores
    Of this land that can't forget its past
    Oh the wind that carries this plane, is the wind of change
    Heaven sent and hell bent!
    Over the mountain tops we go, just like all the other GI Joes


    This is your captain calling--"with an urgent warning"
    We're above the Gulf of Arabia--"our altitude is falling"
    & I can't hold her up--"there's no time for thinking"
    All hands on deck--"this bird is sinking"

    Across the beaches and cranes, rivers and trains
    All the money I've made--bodies I've maimed
    Time was when I seemed to know
    Just like any other GI Joe
    Should I cry like a baby, or die like a man
    While all the planets little wars start joining hands
    Oh what a heaven--what a hell!!
    Y'know there's nothing can be done in the whole wide worldI don't know whats wrong or right
    I'm just a regular guy, with bottled up insides
    I ain't ever been to church or believed in
    Jesus Christ
    But I'm praying that Gods with you when you die!!!
    Last edited: Feb 12, 2018
  22. rdp1210

    rdp1210 Active Member

    How childish! :rolleyes:
  23. What's good for the gander is good for the goose/ You can't have your wing man slagging these terms, when you've... both used them to support your argument/ Funny. "Locking"- don't talk to me about science, when you are using that kind of terminology. I still got loads of dry powder.
    Last edited: Feb 12, 2018
  24. Jeff Root

    Jeff Root Well-Known Member

    Maximally pronated about the oblique MTJ axis: end range abduction and dorsiflexion of the forefoot at the MTJ
    Locked: a clinical term that means end ROM of a joint. Not a good or necessary term

    From a clinical perspective, orthopedists, physical therapists, podiatrists, athletic trainers and many other professions and medical professionals assess joint ROM when treating patients. The quality, range and direction of motion of a joint provide vital information when making treatment decisions. Passive range of motion is assessed with the patient relaxed and the examiner moving a joint through its full range of motion. This is a common clinical practice and technique. The midtarsal joint joint can be moved passively until it reaches a point of maximum abduction, dorsiflexion, and eversion. This is considered the joint's maximally pronated position.
  25. Gerry,
    The choice of terms "damping" or "dampening" are probably not not 100% appropriate for physiologic mechanisms. However, the visual concept of damping may be helpful when we look at postural control strategies which humans employ to maintain upright stance. With the ankle strategy, medial-lateral sway is actually controlled by supination and pronation of the subtalar joint. As long as there is range of motion in the subtalar joint, medial or lateral sway will not transmit torque to the ankle joint, the patient will not fall or sprain their ankle. In this regard, the subtalar joint is "damping" the delivery of torque to the ankle.
    These postural control mechanisms do have significant relevance to the prevention of the ankle sprain. Having a finely tuned ankle strategy requires accurate proprioception, timely muscle activation and full range of motion available in the subtalar joint. Interestingly, proprioception and muscular activation are optimized when there is range of motion available. That is why I am so critical of the orthotic strategies which Eric proposes.
    Best Wishes,
  26. Jeff Root

    Jeff Root Well-Known Member

    "January's newsletter talked about heel bisections and I attempted to impress upon you that the bisection of your patient's cast greatly aids us in producing more accurate orthoses for your patients".
    Kevin Kirby, DPM
    Foot and Lower Extremity Biomechanics
    A Ten Year Collection of Precision Intercast Newsletters.
  27. [
    Disagree, tripe. However, his later stuff redeemed it.
  28. Jeff Root

    Jeff Root Well-Known Member

    Simon, since heel bisection is so important to producing more accurate orthoses for patients, and since heel bisection was used by Root to better define ff varus, ff valgus, rf varus, rf valgus, and the relative position of the heel in the frontal plane, all of which are critical to producing more accurate orthoses, can you please define ff varus, ff valgus, rf varus, rf valgus, an inverted heel, and and everted heel without the use of heel bisection?
  29. rdp1210

    rdp1210 Active Member

    Fortunately we continue to learn. The original term "locked" referred to the pre 1975 work of Elftman who proposed an osseous locking mechanism for the EROM existed. Dr. Root assumed this to be correct (as did everyone else in the world). Dr. Wille challenged this concept in 1975, and designed equipment that ended up proving the Elftman concept incorrect. Root accepted this concept, however the term remained "locking" to describe the EROM of the midtarsal joint, which is really a terrible term, but as long as we all know what it means, that's OK. As Bill Orien explained many years ago, if I hold up a round flat thing that we routinely put food on before eating it, and we all decide to call it a "fork", then that's OK, because that's what we all decided. You don't hear me complain when I visit across the pond and find myself having to use the "tube" or getting on a "lift." It's that everyone in that community agreed to call it that.
    When we evaluate the EROM of any joint, unless bone is making contact with bone, and creating the EROM, then the point of the EROM is determined by the moment across the joint. I see all types of studies in which the maximum ankle joint dorsiflexion is being measured, with no description on how much torque is being exerted around the ankle joint. Do I hear anyone calling foul about measuring the EROM of ankle joint dorsiflexion? No. Yet this EROM is more unreliable that measuring the FF to RF relationship with the MTJ maximally pronated. Yes, we need to know how much torque is being applied across the MTJ. If I had my way, we would have equipment that would give us a FF to RF relationship against torque across the MTJ type of graph.
  30. No it isn't. Heel bisections are all over the place science wise and off the shelf foot orthoses work just as well as custom made devices most of the time according to the evidence base. Sure if you're got feet at the extreme ends of the spectrum in terms of shape- cavoid or pancake- then you might need something custom, but for the vast majority of patients, something off the shelf, without any need for a heel bisection will do. Wonder how many devices daily are off the shelf versus custom on a global stage? Anyway, define "accurate"?
  31. Go ahead then, what's stopping you? A few posts back as you attempted to place an ad hominem logical fallacy against me, you suggested I should make time to research and publish more... I had my last paper on foot orthoses published in a high quality, peer reviewed journal (The British Journal of Sports Medicine) just a little over a year ago; and you?
  32. Jeff Root

    Jeff Root Well-Known Member

    That's totally irrelevant. What is relevant is the fact that custom foot orthoses are being prescribed and manufactured by the tens of thousands per day throughout the world. So today, as we have been for the past fifty plus years, we need to have custom foot orthotic manufacturing protocols. And many prescribers and manufactures utilize heel bisections for orienting their casts and the resulting devices in the frontal plane. And even if you don't bisect the heel, you still need to position the cast and device in the frontal plane by some method. Until someone comes up with a better system and demonstrates to me that it is superior to using heel bisections to orient the cast in the frontal plane and to establish the degree of intrinsic or extrinsic correction in the cast/orthosis I, along with the vast majority of other functional foot orthotic manufactures, will continue to use the current system. You have given us no justification to change our manufacturing protocol.
  33. Jeff Root

    Jeff Root Well-Known Member

    Simon, your argument about problems with current methods and techniques is like arguing in favor of anarchy because the rules of government are imperfect. The fact is the alternative you offer doesn't improve the conditions you complain about and would make matters worse.
  34. No it's not irrelevant, it shows that in order to be successful with foot orthoses therapy we don't need Root, we don't need subtalar neutral, we don't need forefoot to rearfoot alignment because anything with roughly the right shape chucked inside a shoe will work- unless you've got evidence to the contrary, Jeff?
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  35. Jeff Root

    Jeff Root Well-Known Member

    Have you got a study comparing orthoses made at Root Lab to OTC's or to other labs? There are many variables including the methodology, the quality and the consistency of the lab. So your "evidence" does not apply to the devices made at Root Lab.
  36. drhunt1

    drhunt1 Well-Known Member

    tombstone 2.jpg
  37. Don't get me started... here's what does make it worse: your Dad's measurements are invalid, unreliable and unnecessary. You continue, in the face of scientific evidence to the contrary, in attempting to fool naive people that such measurements are valid, reliable and necessary. You have attempted to slow/ prevent the progression of foot orthoses therapy within my profession to maintain the status quo to your own gain. There has been an alternative for many, many years now; an alternative that many, many use successfully on a daily basis. This argument is old, move along, move along... You know when you boys in California were still thinking "the Grateful Dead"... here's what we thought over the pond...
  38. OK so at what point do you we get the evidence so that you might shut the fuck up? Williams et al study- Root devices failed to get patients better but Blake inverted devices did... next.. show me any study published in the last 20 years that supports your position, Jeff...
  39. Jeff Root

    Jeff Root Well-Known Member

    The Grateful Dead routinely played at bar ten minutes from my home in the 70's and 80's!

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