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Theoretical research question

Discussion in 'Biomechanics, Sports and Foot orthoses' started by Graham, Oct 7, 2008.

  1. Graham

    Graham RIP

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    I wonder if you could give your opinion on the following.


    To test X number of biomechanical theories, (three for now) through their application in a foot orthoses, against each other and the no orthotic control, using dynamic gait parameters to be determined.


    Each test orthoses will have a significant effect on the gait parameters tested against the no orthoses control.

    One device will indicate a significant improvement in gait parameters tested against the no orthoses control and the other orthoses tested.


    One subject

    One set of "Neutral" casts

    One lab to produce all the orthoses

    Same base orthoses shell material.


    What gait parameters should be tested?

    How should these be tested?

    What acceptible agreed on "normal/ideal" biomechanical parameters can we use to test against?

    Your thoughts ?

  2. Hey Graham

    I'm no expert on research but my thoughts are as follows.

    Depends on the condition affecting the foot. For eg a foot with a deviated axis might respond better to a Kirby skive than a standard root. Does'nt mean it was better, or even more effective, just that it exerted more of an effect on that patient at that time.

    The gait parameters would also be tricky. How would one measure the significance of kinetic rather than kinematic changes?

    A study should start with a Null hypothesis rather than a hypothesis. One should always seek to disprove ones theory. Also need to define what constitutes an "improvement" in gait parameters. Movement towards a norm? if so, what norm.

    Statistically insignificant. Would'nt show anything.

    Unrepeatable. You'd have to use a single cast and duplicate it. (take casts of the cast for eg.)

    Might need to blind the lab

    What if the different theories required different materials

    All the tests are imperfect. Almost impossible to test internal kinetic changes for example. Damn hard to do force plate analysis with insoles and anyway they are only 3 dimensional. External kinematics could be tested with a motion capture system is the best i could come up with.

    Also you'd have to carry the test through over time to avoid the "spikeorthotic effect" (TM all rights reserved Kevin Kirby and precision intricast, Copyright 2008). Ie, whan an insole is new the sensory effect of the device may cause concious or subconcious modifications in gait due to exteroceptive change which may well moderate or dissappear in time. Familier to anyone who has ever seen a patient walk like a deep sea diver when you first put insoles in their shoe!

    Some evil researcher did a study where they made students sit with their feet in ice water for ages to numb them then watched the changes in their gait:eek:. I forget what it showed. Might have been Hylton Menz but my memory is not perfect.

    See above
    Thats a unicorn. No such thing as a "normal" gait.

    The study you propose has far, far too many variables, especially with only one subject! Might also be worth clarifying what you mean by "biomechanical theories". Are we talking insole mods? assessment tools? Types of insole? Without knowing what you seek to test its hard to construct a methodology!

    Great idea for a thread BTW, very stimulating. :drinks

  3. Craig Payne

    Craig Payne Moderator

    The problem here is that whatever gait parameter you choose to measure if there was a change has to be a parameter that is correlated to a change in patient symptoms or outcome .... so far we do not know what that parameter actually is.
    Why does it have to be a gait parameter? Why not a clinical outcome measure? (eg the Foot Health Status Questionaire)
  4. Graham

    Graham RIP

    Thanks for the replys.

    Shouldn't we be lloking at multiple parameters and seeing what of these an orthoses can change first. Looking at one parameter won't tell us much. Also, if you agree with tissue stress modeling reduction in individual symptoms would likely result in variable parameter changes. I doubt if you could categorically link a specif change to a specific symptom?

    Because we can't tell if we have just made the subject different rather than make them better, re: improve gait parameters tested. Isn't t6his the main concern with current Orthses research?

  5. Craig Payne

    Craig Payne Moderator

    BUT, we don't yet know which gait parameters are clinically relevant.
  6. Graham

    Graham RIP

    Do we not "know" what we believe to be ideal in certain parameters of the gait cycle. We also know that "foot orthoses" can improve symptoms. Hopefully this is by bringing the parameters we know should be ideal closer to the ideal.

    So by testing pre orthoses and with orthoses ,with various theoretical applications, would we not identify the ortoses prescriptions which bring gait parameters closer to the ideal, and then see if theses devices also relieve symptoms?

  7. I don't!

    What is, for example, the ideal position of the Sub talar joint during mid stance?

    Is the same ideal for everybody regardless of physiological variation? Regardless of the nature of function?

    State, if you will, the ideal you seek to work towards.

  8. Craig Payne

    Craig Payne Moderator

    I used to know! :dizzy: Life was simpler then (bit like when 10 degrees was the normal for ankle joint dorsiflexion)
  9. Graham

    Graham RIP

    So when Kevin reminded me to eloquently that he hasn't talked about "Root" for a long time. Did he mean that he has just moved on to another part of the "Theoretical tree" further away from the front line clinician but still of no practical use?
  10. Memories memories.... Funny how the more you learn the less you know! I remember when Simon introduced me to the concept of the triple interface. I lost a lot of sleep that week! Ruined everything i'd held as fact.

    Careful graham. Thems fighting words.

    I think to imply that moving away from root is to become "theoretical" and "of no practical use" is erroneus in the extreme! I suspect what Professor Kirby means is that we now have a rather fuller understanding of biomechanics (due in no small part to his own contribution) and that to rely on 40 year old models is to limit our understanding significantly.

    The front line clinician is, IMO made more effective by an understanding of good theory. The two are inseperable.

  11. Graham

    Graham RIP

    Indeed. And as a front line clinician who now practices 100% sagital plane facilitation with a heel skive here and there, I agree totally. However, creating biomechanical theory and believing it to be a greater understanding is a false doctrine. Unless we devise an objective baced framework on which to test the theory how will it ever become practical to the mainstream, "non accademic" practitioners?
  12. Yes I noticed your profile as "sagital plane facilitator". Interesting approach. What do you do if the problem is not caused by sagital plane blockade? Or do you contend that 100% of pathology stems from sagital plane dysfunction.

    Is not sagital plane progression just another "theory"?

    As to how theory finds its place in everyday practice, I suggest that this is inevitable! The clinician garners data by observing/ assessing the patient, processes it through their understanding of biomx and builds their treatment plan based on this. The only variation as far as I can see is what models / theories the clinician finds helpful.

    I'mstruggling to see where you are coming from here. Perhaps an example of a theory you feel is not applicable in frontline practice.

  13. Graham

    Graham RIP

    Seeing as we walk forward in the sagital plane, any problem which inhibits "ideal" foot function would be regarded as inhibiting efficient motion in the sagittal plane. The diference is we look at the same thing you do but from a different perspective.

    The theory was developed based on observations, using F-Scan and video analysis, looking at changes in objective data with and without an orthoses. When using a conventional device the data anomolies merely changed but did not disapear. When an orthoses was made that actually improved the data to a more "ideal" situation the prescription could not be explained using conventional theory, therfore a new theory evolved to explain the treatment. Thanks to Danaberg.

    How then was "Rootian" principals replaced and what has replaced it? If the majority no longer believes in a conventional varus posted orthoses ,for example, and incorporates a new theory into their practice. What justification can they use for this if it is"just another theory"? How can this new approach be demonstarted to be any better than the previous one. Sagittla plane facilitation utilizes the technology we have available to see if the orthoses actually makes a difference.
  14. Does'nt follow! Take, for an eg, a patient who has had an acute inversion sprain which is resistant to healing. What has that to do with inhibiting movement in the sagital plane? When i see paediatric patients with 50 degrees of Talo crural dorsiflexion, massice talo crural eversion, massive global instability etc, all of which could be said to contribute to pathological function, how can these things be regarded as "inhibiting efficient motion in the sagittal plane?

    Also, you have still not defined what "ideal" function consists of, nor answered whether it is a constant or varied depending on physiology / function. Please do!

    Obviously! Always interesting to see a different perspective. Who, in this context, is the "we" of whom you speak? Are there many 100% "sagital plane facilitators" out there?

    Is this data published? What benchmark is being used? What were the orthotics used in the study? How was the f scan used with the insole in situ?

    What constitutes a "conventional device"

    What constitutes an anomaly?

    What was this orthotic?

    Again, how was the "ideal" situation determined?

    Hard to know without knowing what the orthotic was, however from a point of scientific pedantry you cannot say that it could not be explained, merely that you could not explain it!

    Specifically which theory was this?

    Are we speaking of planterflexing the 1st ray here? Because that fits into several other models including rotational equilibrium and garden variety physics!

    Varies between clinician. However for me the rootian principle of any pathology being explained as deviations from the 8 criteria for normalcy fails for several reasons, not least the lack of any evidence or convincing rationale for the concept of normalcy.

    The principle which replaced it, for me, was the tissue stress model. Into this rather broad concept fit elements of Rootian biomechanics, physics, anatomy, Rotational equilibrium, planal dominance, sagital plane progression etc etc.

    I do not presume to speak for the majority!

    These theorys, which can be better described as models IMO, are all supported by either inductive evidence or deductive evidence. This includes sagital plane theory. I agree that sagital plane progression model has great merit but to say it is the ONLY model which needs to be used, or that it is relevant in all cases is to ignore the rest of the equally relevant and useful models.

    More basis in deductive evidence. More resistant to scientific scrutiny.

    Kind regards.

  15. Graham

    Graham RIP

    Generally we look at most feet to be within "normal" limits. The usual limitation being a functional hallux limitus due to the foots interaction with the artificail flat surface. In extreme cases of gross deformity, rigid or flexible, obviously these are not "NORMAL" OR "IDEAL" and will likely require some incorporation of other models of biomechanical theory to deliver physical control from the device or the footwear. Either way it is still in an effort to improve the efficiency of the bodies progression in the Sagittal plane.

    However, without the benefit of in-shoe dynamic gait analysis it is not possible to determine if this has been achieved or if symetry has been achieved whatever biomechanical principal/s you have applied. This is where pure theory alone fails in the clinical application. I utilize many aspects of many biomechanical models in my foot orthoses but always with the goal to improve symetry and efficiency of motion in the sagittal plane. There is no evidence to support our assumption that the physical anomolies, measured positional "deformities" we think we see actually affect gait in the manner that we think they do.


    F-SCAN and most computer gait analysis systems use what appears to be agreed ideal gait parameters such as those used by Perry. Deviations from the "ideal" can bee seen and hopefully moved closer to the ideal with the intervention.

    With regards to the development of the theory and those who have contributed to the concept I am sure you are aware of Danaberg, Payne, Williams etc. Search "Dananberg" and you will find most of the literature explaining the development of the theory.

    I too believe very strongly in tissue stress modeling. By improving the efficiency of the individuals gait we hope to reduce the stress causing the symptom. However, without atleast some objective in-shoe data we can not determine if we have made the whole picture better or merely different, transfering the stress elsewhere to rear it's ugly head at a later date.
  16. David Smith

    David Smith Well-Known Member


    You wrote
    In what way would you say Kevin Kirby is not a "front line clinician" as you put it?

    Oranges are not the only fruit even if they are your favourite and saggital plane theory (though very useful) is just the same.

    Creating a theory based on sound reasoning rooted in globally accepted convention, ie engineering principles and Newtonian mechanics, is reasonable.
    Believing a theory based on empirical experimantation that is poorly designed and logically flawed from the outset is unreasonable.

    Unfortunately designing experimental research in biological and medical context that has a high logical probability of the singular statement being applicable as a universal statement is very difficult and highly expensive financialy and logistically. In other words designing an experiment where the possibility of falsifiability or, the null hypothesis being accepted, is very high, and therefore when rejected making the probability that the sample applies to the population very high, is very difficult in practice. This means that almost all medical/biological research and its hypotheses are open to reasonable and logical sceptisism.

    On the other hand testing a hypothesis by applying to it the laws of some general Axiom of a system generally accepted as a truth makes it much less open to logical sceptisism. This is becuse we take the universal statement and let it apply to the singular statement. That is to say if we accept that a general law is applicable to most or all things in our experience then to apply it to one more thing is not unresonable or illogical. So, for example, if we accept the general law that force = mass times acceleration, we do not have to test experimentally every singular event to be sure that force was applied when we experience or observe acceleration. Yet by your reasoning we should have to do this before accepting anything and yet you do accept many theories like saggital plane theory and have it firmly fixed in your belief system. Does it make sense?, go figure.

    All the best Dave
  17. :good:

    As usual Dave, you manage to say what i have been trying to communicate far more clearly and concisely than me.

    So what you are saying is that sometimes you use other models but that its still sagittal plane facilitation because we want to improve the entire bodies ability to move forward from A to B and that movement is in the sagittal plane?

    Well, i guess on that basis... Seems kind of a stretch to me! One might as easily say that the body moves in the transverse plane. Only the orientation of the body is different. Its just that in the sagital plane there are only two directions available because one is blocked by gravity and the other by the ground!

    Here i disagree. Just because something cannot be easily tested does not mean it does not have an effect! As has been observed, movement does not cause pathology, FORCE creates pathology. Testing tensile and compressive forces in soft tissues is very hard but these are the things which often cause pathology and must be controlled IN THE CLINICAL SETTING.

    3d pressure mapping is great at finding centers of pressure and mass in the transverse plane and mapping there movement. Sagittal plane biomechanics is concerned with just this. This is the classical gunslinger fallacy.
    I refer you to Daves answer, he put it better than i could.

    What is the basis for these parameters? Agreed by whom? On what evidence?

    This , again, is the gunslinger fallacy.
    You refer to objective in shoe data, yet you are comparing that data to subjective and unvalidated norms! As you know the nature of the tissue stress model (and indeed physics!) is that ANYTHING we do transfers stress elsewhere.

    Here is a question for you, just to keep the discussion fresh.

    Does the F scan have a method for processing 3 dimesional data in the context of planal dominance variation?

  18. Graham

    Graham RIP

    I don't believe I have ever said that Kevin is not a front line clinician! Kevin and I know each other well enough to respect each others clincial and acadeamic approaches. Kevin is far better read in the theoretical world than I and I respect him a grreat deal, even if I don't like his suits.

    Is it, when we have no way to prove that these principals can be applied to a boilogical situation with multiple variables such as the human body and it's interaction with an artificaially created flat surface?

    I agree. But demonstrating improvement in dynamic (time/force) data using equipment based on sound reasoning rooted in globally accepted convention, at least begins to replace the belief with objectivity.

    True if you are dancing to "The Twist" at the wedding this weekend.:dizzy:

    Absolutely, but if you can't test it you wont know the effect.

    If force creates pathology we'd all be pathologic. Force over time when applied to a structure, for whatever reasen, that was not designed to handle the force for the time applied creates pathology.

    If we can't test for the tensile and compressive forces to specific tissues in the clinic is it not reasonable to suggest that we can improve the tensile and compressive forces by bringing known gait parameters, based on sound reasoning rooted in globally accepted convention, close to the ideal. This at least begins to replace the belief with objectivity.

    Agreed, but developing theory without attempting to test it does nothing to improve the sceptisism. In the words of Sir William Osler, "To study the phenomena of disease without books is to sail an uncharted sea, while to study books without patients is not to go to sea at all".

    Like all of us I have to make a living. My beliefe structure has changed and evolved based on the study of the more academic amongst us, and I apply what appears to be most biologically plausible with the evidence, both theoretical and actual, as I can.

    Great discussion, thanks.
  19. Graham

    Graham RIP


    I don't now of any 3d pressure mapping systems! BANG!

    I'm sure Perry and Winter, among others, including the developers of the F-SCAN, might disagree with you here.

    Absolutely, but it would be nice to reasonable demonstrate that the stress has been improved rather than just re-directed to abuse another structure.

    Again, I suggest you look at Perry's and Winter's work. They give the best presentation of sound reasoning rooted in globally accepted convention.


  20. Is not f scan a three dimensional system? And what does "bang" mean!?
    Last edited: Oct 10, 2008
  21. Dancing the twist would be to ROTATE in the transverse plane. Rotating the body in the sagital plane is known as "falling over". The body, when ambulating in an x+ direction, moves in both the transverse and saggital plane. In fact, the X+ direction can be defined as the line drawn where the transverse and sagittal planes bisect.

    Well they'd kind of have to would'nt they. . I know that most force plate measurement systems offer an "ideal". I've never heard any explanation as to how this is arrived at. Any idea? I would honestly be interested to know.

    How can one "improve" a force? A force has no qualatative value. I can see how a stress could be moved to a structure more able to cope with it, but how can it be improved? Do you mean reduced? If so, example please.
    I'd like to. Could you shoot me a reference please?

    How, then, can it be relied upon to feed into the tissue stress model? Given that tissue stress occurs in tissues, for eg in and around joints, how can the f scan tell us what is happening in these joints without information about the axial location of them.

    For eg. Two patients. One has a gross transverse planal dominance, the other a frontal. The first will register on the f scan as having lots of lateral movement, the second not. The frontal dominant foot may register an increased amplitute of y- force in the medial forefoot... or then again it might not! (due to accomodative kinematic change.

    Again, you mentioned objectivity and sound reasoning in the same breath as "the ideal". Again you offer no explanation for how "the ideal" was OBJECTIVELY decided upon. This, IMO is no different to the person on a recent thread saying we should all walk on carbon fibre plates because that is what we were designed for (the ideal) or Ed Glaser saying his MASS position offers the only truly functional and repeatable devices because they hold the foot in "the ideal" position.

    Its only objective reasoning if the ideal is objectivly arrived at. Otherwise it is simply drawing your own target then hitting it.

    As you say, a stimulating discussion.

  22. PodAus

    PodAus Active Member

    Obviously Kevin must be mid-flight somewhere, if he's not tuned in to this thread... :boxing:
  23. Craig Payne

    Craig Payne Moderator

    Pressure systems are 2-dimensional. The pretty pictures they produce are 3-d graphics.
  24. Hey Craig

    Respectfully, i beg to differ. The frame pictures are indeed 2 dimensional information (although those funky mountain pictures might lead the impressionable to suspect otherwise), however they also operate through time, the 4th dimension being as they are, dynamic.

    I would argue, being pedantic, :eek:(not like me) that the 2d information derived from, for example, a Harris and Beath mat or one of those carbon paper dohickies is 2 dimensional, being a static instantanious image in two dimensions. Pressure systems like f scan improve on this by adding the ability to view a gait cycle through time, adding a third dimension.

    I think its a distinction worth making as i feel that so much of the traditional biomechanical assessment is flawed by being static. Always worth remembering that 4 dimensional dynamic function is radically different, that being something pressure systems show rather well.

    Do YOU have any idea what the "bang" meant? :confused:)

    I guess he's entitled to couple of days off poor overworked soul that he is ;). Either that or the flight took a detour :sinking:. Tune in to the next series of LOST.

    Or perhaps he's decided to stand at the ropes with the sponge and bucket on this one, let someone else have some fun!:D

    I'm sure he'll be along.

    Last edited: Oct 10, 2008
  25. David Smith

    David Smith Well-Known Member


    I wrote

    You replied
    But you wrote
    This seems quite clear to me - or did you mean Kevin Kirby's theories have moved further away from clinical relevance and are of no practical use.

    I think many, and especially including me, would disagree. Saggital plane theory is a theory of kinematics which has limiting constraints or boundaries so therefore is quite intuitive. The application of engineering principles and Newtonian mechanics is the theory of kinetics. It does not have easily defined constraints, therefore it is not as intuitive until you can understand the underlying principles.

    (Within a gravitational field) You can have forces without motion but you cant have motion or change in motion without the application of force. Of course motion is easily observed by the human eye and so changes in motion are intuitively accepted as evidence of change in force. Saggital plane theory fits nicely into this niche. However it was the change in forces (Kinetics) that actually reduced the pathology. Forces are not easily observed or intuitive and so not so eaily acceptable, none the less Kinetic theory is more closely linked to reduction of clinical symptoms, ie pain, than is the kinematic.


  26. No, I'm not in "mid-flight". Just getting ready for my Friday clinic of 30 patients. Just observing from the sidelines on this one happily watching Darth Graham being pummelled by "Rocky" Robert and "Dangerous" Dave.;)
  27. David Smith

    David Smith Well-Known Member


    I think you'll find that was in relation to your gunslinger reference and Graham just came in to the saloon and fired a shot at you, or came out into the street, not quite sure which he is?

    LoL Dave
  28. davidh

    davidh Podiatry Arena Veteran

    It seems obvious (but I can't see where it has been mentioned in this thread so far) that in the interests of accuracy someone (its going to be me, obviously) should point out that any measurements taken with F-scan or any other vertical loading gait analysis system are only measuring gait on one surface - a flat, hard one.

    Looking at "normal" gait parameters, one of which is the Force-against-Time curve, on a hard, flat surface, does not accurately tell us whether our gait is normal or abnormal (except in those circumstances where the gait is obviously pathalogic).

    This is not to say that I consider vertical loading systems (VLS) useless, far from it - I use a Tekscan Mat myself very frequently. It is very good at recording "gross" gait parameters such as no heelstrike, very early heellift, non-weightbearing 1st MPJ etc. The problems with VLS are:
    The system is incapable of collecting truly repeatable data due to diurnal variation.
    Data collected is only representative of the subject walking on one surface.

    Data thus gathered should not be taken as "gospel" (as it so often is). VLS systems should be recognised as having limitations and used accordingly.

  29. Graham

    Graham RIP

    Sorry to state the obvious, but isn't this what we do 99.9% of the time? Isn't this the reason that creates the need for compensations and pathologies over time?

    Just a thought!


    to all those in Canada, I hope you all had a great Thanks Giving weekend.
  30. Graham

    Graham RIP

    As most of us don't walk around bare foot, unless you compare this to inshoe with and without orthoses it's not very useful.

    Agreed, but at least it should be used if you really want to know more of what your orthoses is doing, or perhaps not doing.
  31. davidh

    davidh Podiatry Arena Veteran

    This was in answer to "In response to my point about "It seems obvious (but I can't see where it has been mentioned in this thread so far) that in the interests of accuracy someone (its going to be me, obviously) should point out that any measurements taken with F-scan or any other vertical loading gait analysis system are only measuring gait on one surface - a flat, hard one. "

    Graham, check out some pavement, insides of shoes, going uphill and coming downhill, then tell me if you stick by your assertion about being on a hard flat surface 99.9% of the time.
  32. davidh

    davidh Podiatry Arena Veteran

    Unless you are collecting data from your patients in a normal environment your data is only showing how orthoses are working on a hard, flat surface.

    Barefoot data collection is not less useful nor more useful than in-shoe data collection, just different. It records certain gait parameters. It is fairly rough and ready. It is useful for the reasons I mentioned before, and also useful as a patient education tool.

    Unfortunately there are simply too many variables present to make either version of VLSs very accurate - I'll mention a few:
    Diurnal variation, inability to test on more than one type of weightbearing surface, how the patient/subject is feeling on the day, proximal (to the ankle) joint/tissue disfunction or pathology, footwear (for in-shoe systems).

  33. Graham

    Graham RIP

    The hard flat surface, while man made and not ideal, IS the norm for most people most of the time.

    The variables exist in all aspects of treatment applications. Utilizing the footwear of the client on a surface which IS the norm for the majority of the time, we can at least demonstrate a positive/negative affect, and fine tune as necessary, our orthoses to be as functional as it can be for "most" situations. In cases where there are special considerations re: surface, the F-SCAN is mobile!

    Question? How do you, beyond outcome measures, determine what prescription to apply to your orthoses and what effect these have on multiple gait parameters/variables?
  34. davidh

    davidh Podiatry Arena Veteran

    Are you saying that your pavements and walkways in Canada are absolutely flat and that there are no hills/dips:confused:

    I post most of my prescription orthoses 2 degs FF, sometimes I use a RF post too. Its a little simplistic, but it seems to work quite well......

    Agreed-upon outcomes (between pt/practitioner) are the best way to measure how well orthoses are working (IMO) since we don't know for sure what "normal" parameters of gait are. I think CP mentioned in a previous post that normal for one pt may not be normal for another?

    Graham, you also stated:
    "The variables exist in all aspects of treatment applications" which is absolutely true. However we are discussing, and you are defending a technique which puports to scientifically measure absolute or near-absolute gait parameters and alterations of gait parameters using orthoses. You are also suggesting that your results can be extrapolated to include gait on all normal surfaces, which you insist is mostly (you suggested 99,0% of the time) hard and flat, like a gait lab, or clinic floor if you like.
    For me the existence of those variables alone will ensure that your data cannot be as accurate as you suggest.

    Would you like to comment on diurnal variation and how that might affect your data?
  35. Graham

    Graham RIP

    Come on David, you are being podantic. Despite variations in cambre and pitch the basic interface between the foot and shoe and shoe and foot is Flat! Not what the foot was designed to perform on every step.

    2 degrs FF Valgus or varus? RF post when, why and what? Why? Based on what biomechanical framework?

    Are they? What have you changed with the orthoses? Is it causing pressures and alterations in timing which, with your extensive knowledge, would concern you? Has symetry been established? Have you used the same Rx for both sides? How did you determine that the same Rx was approriate for both sides?

    We have a good idea what we would regard as ideal (Winter/Perry et al). Agreed, what is normal for one is not normal for another. Therefore, why would you give basically the same Rx to everyone?

    Not absolutely scientific, but adding more objectivity than just the human eye and a belief structure. I'm not suggesting that the data is as accurate as we would like, only better than without it! Or are you concerned with what you may find?

    No! This doesn't account for night shift workers:eek:
  36. Graham

    Graham RIP


    Interesting quote from you on your UK mail base regarding this thread. Someone dared you to post this on this arena. I thought I'd save you the trouble!

  37. DaVinci

    DaVinci Well-Known Member

    Cheap shot :butcher:

    Attached Files:

  38. Graham

    Graham RIP

  39. davidh

    davidh Podiatry Arena Veteran

    Podantic eh?
    Appropriate/funny - or do you mean pedantic:confused:
    Anyhoo I'm absolutely serious when I say that the "basic interface between the shoe and foot" and the shoe and ground is not flat.
    What incremental values do we use to post our orthoses? Degrees - titchy.
    Usually 2 to 4 degrees. Are you still insisting that in Canada the ground (remember that shoe-wear contributes to this too) does not vary by more than 2 to 4 degrees much of the time (forget Shopping Malls - any of your patients who work in a Shopping Mall will certainly be spending much of the time on a hard flat surface)?

    I cast in neutral and post according to what I see on the cast. If I need to stick my finger under the cast laterally to make the heel bisection more vertical I post valgus, if I need to stick my finger under the cast medially I post varus. If the pt has post tib dysfunction I will usually use a RF post. If I observe minimal heel-strike/early heel-raise I may want to try heel-lift. Its not much more complicated than that for me or my pts.
    Note: Obviously this is not my complete orthoses Rx protocol.

    You asked if I used the same Rx for both sides. Why would I do that?
    You ask if symmetry has been established. Why would you want to establish symmetry as a measure of success? I'm not symmetrical, neither are you, nor most of the people reading this forum thread....
    You talk about adding more objectivity than just the human eye and a belief structure. Certainly, that is the value of any gait analysis system which can produce quantifiable data.

    Do you know what diurnal variation actually is, and the ramifications of diurnal and circadian variation for any type of measurement involving the musculoskeletal system?

    I would point out that blind adherence to one particular gait analysis system could be seen by some as a belief structure:rolleyes:

    Finally, the quote made on the Uk forum, if you didn't recognise it, is a take-off from Monty Python (Life of Brian, if I'm not mistaken) - its a theme we have running through quite a few threads - sad, innit.
  40. Graham

    Graham RIP

    Time for a new thread here I think:confused:

    Considering the significant inter and intrtra relator errors in measurments and the evidence indicating static measurments of percieved positional anomolies has no correlation to dynamic function I am supprised that a clinician of with your experience and accademic reading still practices with these techniques!

    Time for a new thread here!

    Yes. But I always smile when a Brit, pushed into a corner, resorts to the pompous use of an ancient language. Latin is perhaps best used in the bedroom than in a crass attempt at ridicule!

    The F-Scan does not replace an assessment, but adds to the information gleaned from one's clinical assessment and treatment approach. Regardless of which biomagic principal we lean to.

    As an X pat I had the benefit of The Life of Brian. Many of my North American Collegues didn't, and would be offended by this statement. Care and diplomacy is generaly advised when posting on any public/professional arena.


    Am off to Montreal to pick up a buddy from the old country - will be back Monday. A good weekend to all:drinks

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