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Semi Weight Bearing?

Discussion in 'Biomechanics, Sports and Foot orthoses' started by PodKor, Oct 26, 2006.

  1. PodKor

    PodKor Welcome New Poster

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    I am a Podiatry student. I am just wondering if there are any podiatrists, who prefer to use foam impression on semi-weight-bearing? and also what advantages of using this technique over NWB plaster casting, other than it is clean and simple?

    Thank you :)
  2. admin

    admin Administrator Staff Member

  3. to weight bear or not to weight bear

    Dear Podkor

    Welcome to the Forum. Hope you find it a useful resource but beware, it can become an addiction!

    The question you pose is an old one with many good arguments on both sides. There are passionate proponants of both schools of thought,see the other threads.
    To answer your question directly, i use both POP and semi WB foam box casting but mainly the latter. This is partly because i adhere to the view that a certain amount of simulated GRF allows the soft tissues to deviate as they would in normal wb. I feel this allows me better control of the bony structures. This is not a universal view but i beleive it is not without merit.

    Also all of my patients are 15 or younger. Ever tried to POP cast a 2 year old with downs? Short of concussion or Chloroform foam box is generally a good deal easier!!

    I beleive foam box has been shown to be more repeatable than POP casting. However it cannot be seriously disputed that POP NWB casting gives you the maximum degree of controll of the foot position. (IMHO)

    Hope this helps

    Robert Isaacs

    "May your knowledge and skill be the honey in this out hive of unusual physics and cruel gravity" Steven Lassiter 2004
  4. David Smith

    David Smith Well-Known Member

    Dear PodKor

    Foam impression is my least favourite technique to capture an impression of the foot.


    It can be difficult to control the position of the foot and ankle as the impression is made.

    One doesn't know and has no control over the stiffness of the foam.
    How does one know how hard to push the foot, and where to push on the foot, or if to push on the foot, to get the correct relative foot position.

    EG Its difficult to capture the 1st ray plantarflexed if that is required.
    Can one capture the equinus position of the fore foot or does it just flatten to the same level as the heel?

    One relies partially on the patient to control the foot position.
    If the the patient moves their foot, to late, the new foot shape is also captured so you have to start again.

    Once taken it is difficult to assess the impression and compare it to the foot as seen on the couch.
    This can be over come by taking a positive plaster cast but then its not clean and simple anymore.

    I think the foam stiffness tends to have a dorsiflexing effect on the ankle so that one must push on the forefoot to approximate the normal w/b position.

    But what if the 1st ray is stiff and the lateral column is compliant to GRF how will it be possible to gauge how hard and where to push on the forefoot.

    I can't think of any advantages to using a foam impression box apart from ease and convenience.

    Cheers Dave Smith
  5. David Smith

    David Smith Well-Known Member


    Repeatability = Precision = Accuracy = Reliability? No it doesn't. Repeatable results do not necessarily indicate accurate reliable results. Foam impression may quite well capture the same wrong impression time and time again. The PoP cast is more subjective and therefore intrinsically prone to variation.

    I tend to agree with the points you made about young children and soft tissue compliance but how do you deal with joint stiffness / compliance and relative segment position?

    Cheers Dave Smith
  6. I said this was a contentious one :rolleyes:

    Did i say that? DID ANYONE HEAR ME SAY THAT?!?! :mad: NO. I absolutely agree that repeatability does not make Foam more precise, accurate or reliable. Nor indeed accurate. Certainly not more useful or better! I'm not even convinced that POP is more subjective as you state. It's just as easy to balls up a foam cast! I should know, i've done it oodles of times! I am the undisputed master of C*****g up foam casts! My loft is insulated with the wreckage of a thousand failed attempts! I just stated it was more repeatable. Just a bald statement of fact.

    rant over. Sorry. I feel better now.
    Deep breaths into paper bag.

    My OPINION (not saying its right, just that its mine) on the rest:

    , you get familier after a while. Granted it's subjective but then so is POP
    , until it starts sinking into the foam
    , Depends on what shape i want the foot in but i generally push on the top of the knee, that after all is where the downward force usually comes from, hold the stj as near to where i want it with my right thumb and fingers and push the forefoot down at the same time with the heel of my right hand. The position of the forefoot/1st ray depends what i'm trying to acheive with the device.
    , erm yes? otherwise it just sits on the top of the foam! duh.
    , Depends what position you are going for! Is there a single correct position? if so what is it?

    I ask the patient to relax their foot completely whether i am casting POP or foam. So far most of them are singularly unco-operative with both equally! I certainly don't ask the patient to hold or push their foot in a certain way if that is what you mean.

    Agreed. I do.

    As i said there are valid arguments on both sides. Vive le differance and that.

    Out of interest and slightly off topic, most labs slap masses of extra plaster "correction" on your lovingly and accurately cast negatives because if one allowed the Carbon fibre to follow the medial contours of the arch exactly it would cut into the foot when the foot tried to pronate on WB (and no doubt other valid reasons). I wonder if the debate around the minutiae of soft tissue deviation and 1st ray position is located at the right point in the production process. Just a thought.

    Kind, fond and loving regards,

    Robert Isaacs
  7. Phil Wells

    Phil Wells Active Member


    Just to play Devils Advocate a bit, but how do you know that when taking a POP cast that the forces you apply to 'correct' the foot are appropriate to ensure that the cast is correct?
    Also, how relevant is a non-weight bearing impression to the pathology that in most cases is associated with GRF?
    I use both methods but have found that the foam box's are also very useful for a bit of semi-quantative assessment e.g. if a flexible forefoot valgus is identified, then it can be seen in the fb if a semi weightbearing technique is used.
    Re assessing the cast, it is fairly easy to measure forefoot alignments in an FB using depth gauges and is a 1st ray addition is needed, then put in in yourself.
    However when I am in doubt I will do both techniques to help me decide on the ortho prescription.

  8. EdGlaser

    EdGlaser Active Member

    I think that the material you cast in is secondary to several factors including accuracy, repeatability, ability to capture the correct position, but most important is technique.

    I therefore use only foam and my lab only accepts foam casts but we have a very particular technique that accomplishes all of the above. Craig showed in his 2003 Jan. article "Variability of Neutral position Casting" (close to the title) that POP is very inacurate and non-repeatable and the test was done on his foot which is quite rigid....I think the results would be worse on a flexible foot.

    The technique I use is called :Gait Referenced MASS position casting. We attempt to pass force through the foot in as close to an ideal gait cycle as that patient can tolerate with their individual anatomy. Thus the cast is very custom for each patient and yet gives them the maximum amount of correction that they can tolerate without over-correcting. We use the floor as a "frame of reference" which dramaticall improves repeatability (research just completed in McMaster U. in Hamilton, CA showed that the intra-operator repeatability was far greater than plaster) in practitioners that have been doing plaster for 20+ yrs. and had 5 min. of instruction in this technique. The technique is as follows(for casting patinet's right foot):

    1. Patient seated on the edge of the chair.
    2. Socks on, pulled up...reduces skin lines.
    3. Knee directly ove the ankle....mimics midstance.
    4. Foot centered in the foam front to back with more space on lateral side of foot.
    5. Right hand across right knee....fingers on lateral knee preventing abduction.
    6. Left thumb under the neck of the first metatarsal.
    7. Maximally invert the forefoot while making a vertical shoulder thrust on the knee to bottom out the heel fullly in the foam. Every step bottoms fully in the foam...frame of reference....you will always push them to the floor, never through the floor.
    8. All eight finger tips placed along the lateral side of the foot between the fourth and fifth mets from the styloid to the pinky toe and vertical thrust to the bottom.
    9. Thumbs on the toenails and plantar flex the MTP's to release the windlass effect.
    10. Depress all of the met heads completely with the thumbs (a rolled up washcloth will make this more comfortable).
    11. Double check the met heads and lateral side are completely bottomed out.
    12. Final thrust from Dorsal anterior medial to plantar posterior lateral to seat the heel without depressing the arch.
    13. Lift the foot from the foam and pen test. Place a cone shaped object like a bic pen into the center of the heel, fifth met head and first met head to just touch the cardboard box and check that there are equal size holes.....tests that the forefoot and heel are on the same plane. Feel across he met heads to make sure that there is no transverse arch. If either test fails....place the foot back in the foam and re-press the failed area. Not sure it is good....start over with a fresh box.

    We certify all clients in this technique before we allow them to even use our lab. A good cast will make a good orthotic unless you cast in POP and arch fill then the cast is a show for the benefit of the patient because the shape of the orthotic has no relevence to the cast anyway.

    Hope this helps..
  9. Peter

    Peter Well-Known Member

    Robert said
    Robert, Are you are trying to say that the technique itself of obtaining a foam cast is more repeatable than POP casting, rather than the negative foot impression ?
  10. repeatability


    Nope I'm saying i remember on one of the other versions of this thread there was a study quoted which found that the cast produced was more repeatable. I'd look it up and quote it specifically but I'm on a dial up connection which means it takes ages for a page to load. But it is there.

    What was the article that showed POP to be inaccurate?! Poor repeatability is one thing but how does one measure accuracy and against what criteria? Was a similar study carried out on Foam? Craig, some details on this would be nice! Are you being misquoted here? And as david very rightly pointed out some while ago in this thread (must be oh at least 2 hours!) repeatability is a very small aspect of the equation. I suspect a full out solid weight bearing foam cast would be more repeatable still, but it would also not do anything useful.

    This is an exceedingly large statement to make. Very bold. Just because the insole ends up a shape other than the one origionally cast surely does not mean the cast has no relevance. if you put a chair on a table and sit on it the table is still relevant to how high you are even if you are not sitting on it directly. Oh Damn here we go again with the Is-MASS-the-only-position-which-works debate. Can we not and pretend we did? It's been done to death at least 18 times! :(

    A word of warning for you now this debate has run rampant again. Beware of anyone who claims to have all the answers. Ed's MASS system may be repeatable but informed minds would like to know whether it is repeatable in an EFFECTIVE or appropriate position. This has yet to be proved. I would recommend reading some of the (MANY) other MASS threads and making your own mind up on whether this technique is for you.

    Kind fond and loving regards to all
    Robert isaacs
    Last edited by a moderator: Oct 27, 2006
  11. Craig Payne

    Craig Payne Moderator

    There have been several studies on repeatibility/variability of casting. Those methods that involve a weightbearing (semi or full) are less variable than non-weightbearing methods. These studies do not show one method to be better than another, just that there is less variability between clincians with the (semi)weightbearing methods.
  12. accuracy / repeatability

    Thankyou Craig. I thought a study which showed any kind of casting to be inaccurate was rather a big leap from being more or less repeatable.
  13. Peter

    Peter Well-Known Member

    Many years ago, for my final year study/dissertation, I examined the reproducability of successive casts taken from a single foot, using both the "suspension" and the "direct pressure" techniques.

    The casts were taken by an experienced (and published) tutor and clinician in Podiatric Biomechanics. I undertook the analysis.
    This obviously isn't published literature (grey literature), and I am fully aware of the many, many shortfalls in this study.

    I cannot recall all the exact measurements, however forefoot;rearfoot realtionship was one of them.

    Some of the purists might be surprised to hear that the "direct pressure" technique casts showed less variation in successive casts.

    Something for the weekend, amd I am disappointed to have to sign off til Monday.

    Have a Good One!
  14. David Smith

    David Smith Well-Known Member


    Blimey are you having a bad hair day ;)

    Anyway is the foam cast more repeatable or is it very subjective and prone to variation and cockups? Which is it?

    I'm not a great supporter of PoP casting Its just that I believe overall the limitations and shortcomings of the POP cast are less compromising than the foam box but both are subject to skill, judgement and error.

    My favourite is my Amfit Footfax scanner, which give a 2D and 3D computer image of the w/b or sw/b foot in any and all positions desired. The Karma Sutra of foot impression techniques one might say. But this still has its limitations and about 40% of the time I use a POP cast. The other day I used a Foam box for a young boy who was a figgity little guy who didn't have the attention span of a goldfish. His Direct milled orthoses did turn out very well.

    When I use a PoP cast I use a lab that can direct mill. I have found this to give a superior result to the traditional method of cast additions and correction using plaster. This also is a similar technique to my Amfit system that direct mills my computer design from an EVA blank.

    The errors with plaster addition and correction that you point out are applicable to both POP and Foam box so we should only consider the preperation of the negative mould, but surely this will doubly compound the errors of foam box impression.

    I believe that Direct milling gives a better finished characterisation of the plantar contours than does the traditional methods but I expect to be contradicted here.


    I don't know anything about the forces required but I do know the shape I'm looking for, which I do not think is easy to do with a foam box since one cannot see the footshape while making the impression. I can see that with experience and skill one can estimate the foot position in the box and review it when the foot is withdrawn. This is ok but puting the foot in and out of the box seem open to more error to me.

    What do you think about direct milling its just up your street isn't it?


    Your technique of reducing the mass acceleration, so that force time curve is longer and flatter, (debatable) at an earlier stage necessitates a highly supinated cavus position of the foot that perhaps can only be captured by the foam box technique. Pushing the forefoot level to the rearfoot and the lateral border to the bottom of the box seems to simplistic to me and what maximal supninated position means in this context, I don't know, but we've been to a similar place before.

    I agree Robert Vive la Difference, if it works!

    Cheers Dave
  15. PodKor

    PodKor Welcome New Poster

    Thanks alot for the replies.
    It s really good to see lots of different opinions. :)
  16. David Smith

    David Smith Well-Known Member


    Start to sink? 1cm 2cm right to the Bottom of the box what is it?

    Exactly, so how far in do you push it? how do you know the saggital rearfoot to f/foot orientation? What if you want to capture the forefoot lower than the rearfoot. Unless you go right to the bottom of the box how do you gauge the frontal plane orientation of the foot. What if you want to capture a compliant lateral columb in an elevated position? How do you ensure the lateral arch is raised in a way to support the cuboid in a triplanar way?
    How do you ensure the 1st ray is plantarflexed without everting the whole forefoot into a valgus position?

    I can do all these things with my Amfit and most of them with a PoP cast.

    I would be very suprised if by using all these criteria foam box impressions were more repeatable than PoP.

    The correct static position for casting is the one that the clinician decides upon.
    Hopefully it also characterises the correct dynamic position to relieve functional pathological forces on the tissues of interest.

    Robert I'm not critisizing you for using foam box (who am I to do that) just arguing the reasons why I prefer PoP and Amfit and Direct milling.

    Cheers Dave Smith
  17. pop vs foam


    Reading back it is just possible that i was a wee tage defensive there! sorry bout that.

    The point i was trying to make via excessive hyperbole was that IMO both POP and FOAM can be got very wrong. It really depends on who does it and how. I wasn't trying to imply that foam was better.

    As you say with practice you can get to recognise the position of the foot from the top view. I would advise anyone to start by pushing the foot to the bottom of the box and only try to get clever with floating casts when they've had a few years practice.

    As to the other positional variations i'll grant they can be tricky. However ithink they are doable. Bear in mind you can always take the foot out to check the position then put it back in and push a bit more.

    I tend to find i get more lateral arch than i generally want! Strange but true.

    I LIKE your thinking on correct position. Its sometimes tempting to shoot for a perceived ideal position rather than working out whats best for each individual.

    And yes the hair was terrible! ;)

  18. EdGlaser

    EdGlaser Active Member

    How can a technique be accurate without being repeatable? Are you aiming at a different position each time? If you are trying to achieve a particular position, and each time you get something different, then how can that be accurate? How can the two be divorced?

  19. EdGlaser

    EdGlaser Active Member

    Once again, if you are attempting to attain some certain position, and you get a different position each attempt, how can each attempt be accurate? Accuracy is dependant on repeatability which is dependant on frame of reference. Holding 26 bones out in space with no frame of reference will not yield repeatablility.

    They just finished one in Canada (just submitted for publication) as I mentioned earlier and foam came out much better than POP.

    I disagree, repeatability is very important if shape or position matter at all or if forefoot to rearfoot relationship matters at all. If the cast gives you no real data about these, then what good is it: size of the foot.

    If shape of the foot is unimportant, then why do you take the cast?

    Like I told Einstein….It’s all relative. :)

    I invite this research, am willing to fund it and since my research challenge was unanswered, I will do it myself soon.

  20. Craig Payne

    Craig Payne Moderator

    I just think we may be talking a different language here.

    To me, accurate means how well the casting technique reporduces the actual shape of the foot - to me all methods do that really well, ie they accurately reproduce the shape/position that the foot is held in (this does not mean that foot was held in the "correct" position to start with and this can be debated) - it still accurately captured that position.

    Reproducibility, to me, means the ability to reproduce that position (ie repeatibility). This can be intra-clinician reproducibility/repeatibility (ie how well an individual clinician can repeat the cast in the same position (again, this does not mean its the correct position) or it can be inter-clinician reproducibility/repeatibility (ie how well an 2 or more clinician can repeat the cast in the same position) - in our publication we called this varibility.

    Our conclusion was the NWB casting had a lot of varibility between clinicians (ie poor inter-clinician reproducibility/repeatibility). In our other study of a WB system (the FAS) we showed it has less varibale between clinicians (ie good inter-clinician reproducibility/repeatibility). If you look at the other studies I have had access to (some soon to be published), the results are consistent - more varibility between clinicians if a NWB method is used and less variability between clinicians if a WB method is used (and there are several WB methods).

    Accuracy, varibility, reproducibility and repeatability, to me, have nothing to do if the method of negative model production is actually the correct positioning of the foot or not in the first place (thats a different research question)
  21. Agreed. The research showing lack of significant statistical differences in outcomes between preforms and casted devices demonstrates that casting techniques may have very little to do with orthotic efficacy. We await the numbers to prove any of the conjecture regarding foot position during casting.

    Riddle me this: why should there be any single one "optimal position" for casting when on a daily basis the foot has to achieve multiple movement and support tasks, in multiple environments AND is free to move on top of the orthotic shell? Furthermore, when biomechanically induced foot pathology has multiple aetiologies?

    The only technique which can accurately achieve all of this is the FOS technique (copyright). As the inventor of the FOS technique, I have vested interest in its success, therefore I'm willing to do the research myself to prove the "fact" that this position is "better". Don't worry, I'm an experienced researcher and will "buy" in other experienced researchers to help with these studies to overcome any potential bias.;)
  22. Shape Capture


    Ah how i love the cut and parry of reasoned discourse. World would be a considerably more dull place if we all agreed!

    To enlarge on one point which i feel is significant, and not yet done completely to death:

    I don't think the shape of the foot is unimportant, far from it. However i sometimes want an orthotic in a shape which is hard / impossible to cast in. The foot only passes through the semi WB position in which it is cast in mid stance and that only for an instant. Given that any cast is in three dimensions and the foot operates in 4 dimensions i sometimes want to alter the shape to reflect this. As Simon very astutly points out the foot has to carry out many support tasks at different times and is not, in truth, held in the orthotic position for the whole of the gait cycle. For me the cast position is a starting point and IMHO modifying it does not detract from its relevance.

    What say you? anyone?

    Peace and love

  23. John Spina

    John Spina Active Member

    You can use semiweight bearing.I do not as Iprefer the plaster casts as I find this to be better for me..but semiweight bearing is certainly a good enough technique as it does plantarflex the first metatarsal.
  24. No, Simon, I have created the only technique which can accurately and reliably achieve all of the requirements of a negative cast and I call this the PASS [Perfect Arch Super Suspension] technique (copyright, patent pending). As the inventor of the PASS technique, I will challenge any other individual against my team of experts (that I pay very well to do research for me and "prove" that everything I say and everything that I invented is better than anyone else's). Be sure to come to my company's website www.perfect-arch.com where I have listed numerous testimonials from enthusiastic customers to show that all other orthosis labs are just not up to my standards because I spent at least 15 years experimenting in my garage inventing all of these wonderful new ideas (of course I know that they are new, but never really bothered to investigate if anyone else had ever done them before).

    To show that I am not in this business for the money, I live in a triple-wide trailer outside my lab because my whole goal in life is to make as many perfect arches as I can. In fact, my company's slogan is "We Create Perfect Arches!" Our phenomenal growth (we will soon be buying the state of New Hampshire to occupy the lab's enormous growth rate) attests to our superior product. By the way, I can't respond to any e-mails right now about my ideas or company since, even though I don't make much money in this business, I'll will be vacationing in luxury hotels in Maui, then Europe, then Brazil, then Nova Scotia, with my family. Of course these vacations are timed somewhat mysteriously every time someone asks me a difficult question. But, hey, I know this isn't a problem since I know that everything I invented is the best ever, even though I haven't bothered to speak to any real experts about my work. I stay happy because I only choose to associate with individuals that agree with me and my great ideas!! Life is great when you are the smartest entrepreneur podiatrist in the whole world!! I am glad I am him!!:p
    Last edited: Oct 28, 2006
  25. Ian Linane

    Ian Linane Well-Known Member


    I know you Americans like to go in for facial jobs but I must admit to being impressed by your new image on the new site. Have you been practicing the enticing eyes look for very long. Did it cost a lot of money?

  26. pass casting

    I feel really inadequate now. I havn't invented anything and i can't even get into MY garage because the hose has knitted the bikes to the mower. :(

    Oh what the hell. I've just invented the QGAR (quite good arch really) system, Copyright pat pending as seen in My parish mag making me published. Its ace. My mum says. Ha so there. :cool:

    No I am sparticus. No I am sparticus :rolleyes:

    Sorry Ed, nothing personal.

  27. Atlas

    Atlas Well-Known Member

    Ed, can you direct me to a PDF file showing this technique?
  28. EdGlaser

    EdGlaser Active Member

    True. I was thinking that accurate meant that the desired position was captured with little variability. Accuracy by your definition would be high for any technique because whatever position the foot is in, as long as the cast reflects that position…it is OK but without repeatability it is almost meaningless for manufacturing because the lab cannot “trust” that the cast has correctly positioned the foot. The only way inaccuracy can be introduced by this definition is if the method deliberately changes the shape of the cast for example via manipulation of a wire-frame in a 3D computer model. It seems that many labs introduce this arbitrary variable by adding plaster to the positive….arch fill whether that be minimal or maximal it is always a departure from the original cast and introduces inaccuracy. There does not seem to be ANY science behind exactly how much arch fill is needed for a particular patient. It is a WAG based on what that Guru thinks. The information is channeled from spirits in another dimension to the guru who magically applies the exactly correct amount of plaster to the arch. In this diagnosis we use this much arch fill and for that diagnosis we use another amount that is not measured by the lab or standardized to mean anything and if they have both diagnoses we hope for an answer to come to us in the shower.

    From a manufacturing standpoint, we (at Sole Supports, Inc. ) want to capture the position of the foot that, when duplicated in plastic will yield a shape that allows the orthotic maximum contact with the plantar surface at midstance in the maximal supination tolerable with that individual person’s anatomy, ….so that when the center of gravity passes over the foot at midstance and heel lift begins, the foot is stiffer in the sagittal plane creating a more efficient transfer of force from the muscles and superstructure momentum to the forefoot for better propulsion.

    In manufacturing Sole Supports (I cannot speak for other labs), both accuracy and repeatability are very important. Without both, how can we really call an orthotic “custom”? If the only difference between the shape of one orthoses and another is the size and degree of tilt it is placed on, then isn’t it really a “customized” prefab. This explains why “customs” and prefabs perform similarly….especially if the prefabs can be “customized” like the new Alzner or Phase 4 or Foot Leveler.

    The third “group” of casts in your study….one clinician casting the same foot 10 times, (your rigid foot), was INTRA-operator reliability and had the same forefoot to rearfoot variability. I hope if you re-do the study you use a more flexible foot type that has a ROM to really show the variability that is inherent in NWB casting. It is scary.

    Here lies the real controversy. I have read criticisms on this site over and over of the MASS position that I propose but not one person has proposed a different position to cast the foot in or is even brave enough to say what position they put the foot in. Many criticize “neutral” but do not propose an alternative. This position for this diagnosis and that position for another in a technique that is not repeatable (inter or intra)….again, what if the patient has both. To the showers guru must go.

    Kirby’s pictures in Does plantar contact necessarily = control? Thread post #5 show how far off you can be. I think that this kid in the picture is no where near the MASS position and the popped out Tibialis Anterior muscle on the orthotic shows that he is not “resting” on the device. If that is an example of using higher MLA it is a joke or just shows how flat his usual orthotics are. It does illustrate the fact, that I have been saying all along…..when you wedge the rear-foot enough you finally begin to create an arch…..not enough in this case but enough to block the terminal “tissue stresses” without making a significant change in function.

    If someone else has the “right” position to put the foot in accurately and in a repeatable fashion, please come out of the closet.

    Until then practitioners have a choice between the MASS position (Not patented or patentable and usable by anyone who wants to try the casting technique described) and “Neutral” (Also referred to as the FOS (Simon Spooner), PASS (Kevin Kirby), and QGAR (Robert Isaacs)).

    Funny, it seems that the “snake oil” here is the status quo and the “snake oil salesmen” are very upset to find a new paradigm emerging that replaces their snake oil with something that at least makes sense and is the subject of active research, being validated independently in respectable research institutions that are non-biased. We are proud to fund those researchers and will continue to do our own research even though it will be considered biased by some.

    With Deepest Respect,

    PS: For many of the studies we only supply the orthotics to be tested for free, others we fund the stipend for a grad student and still others we provide funding for specific equipment that the researchers need to do better testing. In one case we fabricated a device that starts cameras and force measurement equipment simultaneously for better accuracy. We do not even get to read the results before publication.

    PSS: Since I consider you to be among the least biased and (having spent a day with you) the highest integrity, I would be more than willing to give you an open research grant to be used at your discretion to test Sole Supports theories. I anxiously await the proposal.
  29. EdGlaser

    EdGlaser Active Member

    Putting the foot in an impossible position?


    If it is impossible to put the foot in that position for casting, then how will the orthotic accomplish this? Please explain.

    What is IMHO?

    You nailed it Robert. The “starting” position is exactly what MASS position is. Flexibility allows the device to respond in a time dependant manner and change shape as the changes in the gait cycle occur. How much flexibility…..callibrate.


    Ed :)
  30. EdGlaser

    EdGlaser Active Member

    Finally we agree....You use the FOS position


    MASS is a starting position. Calibrated flexibility allows for most temporal changes although it is certainly possible to over power any device.

    See, here we both agree. FOS is the same acronym I would use to describe the position you put the foot in although most would call it “neutral”.

  31. EdGlaser

    EdGlaser Active Member


    I speak to you, Simon, Eric, Robert, David on this forum....and you certainly do not agree with me.

    A few years ago I had a 2 1/2 hour lunch and a 4 hr. dinner with Bill Orien.

    Robert D. Phillips, Eric Fuller and Craig have spent time with me (just to name a few)....certainly not agreeing with all my ideas.

    In just the last few weeks I met with:

    Jack Morgan, DPM : he headed the laboratory that did Merton's original research in the early 70's, Tom Scarlotto, DPM author of the Compendium in Biomechanics and a creative genius (and his wonderful wife, Billy Jean), Franklin Kase, DPM and Dan Altchuler, DPM (two of the most brilliant biomechanically oriented podiatrist on the planet), Jan Tipper, DPM (a real critical thinker with a passion for the subject), Alan Ross, DPM, and severl others.

    I have always sought out the greatest minds in biomechanics to discuss my theories with. I am not saying that they agreed with me, there was much critical discussion but this is how I learn and we all advance.

    I consider many of my clients and those on this forum to also be among the best biomechanists in the field.

    Yes you are right, those on my team are truly phenomenal!!!! I cannot say enough great things about them. Don, Stu, Bill, Matt, Alyson, Les, Jared.....all the best of the best. I pay them well but I plan to pay them much much better as we can afford it....they are so so worth it. I hope that they feel as excited about being part of my team as I am appreciative of having them. At the risk of getting personal, I would be remiss if I did not mention my Goddess, Pam (my wife) without whom I would have no reason to go on. I am truly blessed beyond my wildest dreams.

    Thank you,
  32. EdGlaser

    EdGlaser Active Member

  33. Phil Wells

    Phil Wells Active Member

    Re direct milling, thats all I do but I am lucky in that I see the patient, take the impression, scan it into my computer and then design it - not many people are that lucky. I also get the choice of what material I am direct milling.

    I have also recently decided that I prefer that foot impression are received as foam boxes as I can get a lot better idea of the technique used by the practitoner and correct/adjust them appropriatley. A bad fb is far easier to 'interegate than a bad POP. However, a good POP is a wonderous thing and when coupled with a good prescription gives the better devices, IMHO.

    I do like the Amfit system and in good hands can give great devices.

  34. casting position and temporal variation


    Firstly your idea about a guru is laughable. Every GOOD biomechanics uses native indian guides. ;)

    A point not without merit. However i think subjectivity is not something we should be afraid of in biomechanics.

    Oh and IMHO means in my humble opinion.

    Yipe. Reading that back i've just realised the limb i've gone out on has started to creak. I've actually hinted at how i tend to do things and now i'm going to have to justify myself. OK here goes

    IMHO (and i stress that this is only my opinion, i'm not saying it's proven or indeed the best way for anyone else, just that it works for me).

    When designing an orthotic we all consider all four dimensions. The MASS position, in your words, uses
    Although my designs tend to have an element of this involved i also consider that the position of the foot at each stage in the gait cycle and the GRF (or ORF if you prefer) changes through the stride. Therefore the orthotic does not always dictate the shape that the foot forms at all moments during gait. Producing a device in a shape i cannot get the foot into is an extreme example but generally i consider what forces will be acting on what parts of the foot at what times. If i want to manipulate those i will modify my casts accordingly. Thus if the function of the foot only becomes pathological after heel lift i will focus on forefoot modifications. If the foot is in a bad position at heel strike the posterior half of the insole will occupy my attention.

    Also if i am using elastic materials such as ppt, pseudo biological materials like maxacaine or memory plastics like V9 in conjuction with heat mouldable materials to manipulate the ORF beyond what i can acheive with "dead" materials or patterns, like a shank dependant EVA block, the shape of the device when no weight is upon it may be different from the shape when in situ. Thus i seek to create ORF when the foot is in the a position where it would not otherwise occur.

    I eagerly await being ripped apart my all my learned colleagues for using shamelessly subjective techniques without any research backing them up. Enjoy yourselves. Especially you Ed, it'll be nice for you to dish it instead of taking it for once! :eek:

    Robert Isaacs

    PS. I'm probably the only one on the furum who has not twigged what FOS is an acronym for. Given the source i suspect it to be obscene!
  35. faultless orthotic system ;)
  36. David Smith

    David Smith Well-Known Member


    What is the 4th dimension?

  37. Dave you need to watch Dr Who :)
  38. David Smith

    David Smith Well-Known Member


    Oh stop it! I was resiting the urge to extract the urine.

    This is a serious forum and I am eager to explore new dimensions.

    What time is Torchwood on?

    Only pulling your leg Robert ;)

    Have a good one, Dave
  39. dimensions

    Unfortunately no one can be ... told , what the 4th dimension is. You have to see it for your self.

    Morpheus. kind of.

    Beam me up scotty.
  40. Atlas

    Atlas Well-Known Member


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