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Is It Unethical to Prescribe Orthoses for Children with Asymptomatic Flatfoot Deformity?

Discussion in 'Biomechanics, Sports and Foot orthoses' started by Kevin Kirby, Dec 1, 2014.

  1. My brain could do with a work-out so I'll play, Kevin.

    The dichotomy you propose at the end of the piece is somewhat artificial, but let's ignore that for now and focus on your second option:

    “Yes, Mrs. Smith, I believe we should treat your flatfooted child with specially-designed custom foot orthoses that will decrease the pathologic forces acting within your child’s foot and should improve gait function so we can not only improve (his or her) ability to participate in walking and sports activities, but also hopefully prevent further progression of the flatfoot deformity into adulthood”?

    Specifically, I'll start with the portion of your statement that I have made bold: if the child had pathologic forces acting on their foot, then surely they should have pathology; they don't because as stated within the title of the piece, they're asymptomatic. Viz, the child does not have pathologic forces acting on their foot for the foot orthoses to modify- right? If this is true, are we misleading and perhaps lying to the parents if we were to make your statement above? Is it ethical to mislead and lie to patients and/ or their legal guardians?

    When does a force become a "pathologic force"?
  2. Admin2

    Admin2 Administrator Staff Member

  3. Rob Kidd

    Rob Kidd Well-Known Member

    Yes, I was one of the authors of the paper references by Kevin. The key words or phrases in our paper were (are): asymptomatic, and "may be acting in an unethical manner". That does not mean "are acting in an unethical manner".

    Now, to look at your words more closely. In paragraphs 4/5) you mention the works of John Weed and Ron Valmassey as if their practice gives ethical credibility to your decision making process. Just because they do something, does not make it right; AND, does not make it wrong. We have had this conversation before..............

    More to the point though, in paragraph 5), you talk about symptoms, such as asking to be carried on long walking trips, tripping, appearing clumsy, complaints about knees, hips or back. These are symptoms, as you well know; if a patient has these they are decidedly not asymptomatic. I do however, recognise your comment about family history.

    In paragraph 9) you throw in a straw doll, which I suspect you knew at the time; if the patient was genuinely asymptomatic, you have no case whatsoever for making a statement such as ".... will decrease the pathologic forces acting within your child's foot..............." There is no evidence at all that such forces exist.

    To put that another way: first invent the disease, now find a manner to remove it.

    Let us come back to asymptomatic; this scenario does not present an asymptomatic child - at your own admission.

    Mandy and I are a little amused that while our publication caused some fuss at the time, including in the US (see letter in JAPMA from an elder statesman), it is now 16 years old; why the fuss now? This should have been debated many years ago.

    Rob Kidd
  4. The question of whether forces or moments can be pathologic without causing subjective complaints is really the key here. In this context, the definition of pathologic I used in my article is "extreme, excessive and markedly abnormal" rather than "a disease".


    Can a flatfooted child have pathologic (i.e. markedly abnormal) amounts of external subtalar joint (STJ) pronation moments but still be asymptomatic? Yes.

    Can that pathologic (i.e. markedly abnormal) amount of external STJ pronation moment cause gait abnormalities that affect the child's ability to walk and run, but may cause no subjective complaints otherwise? Yes.

    Can the flatfooted child, who has no painful symptoms, have pathologic (i.e markedly abnormal) amounts of internal bone compression forces which, over time, have the potential to alter the ultimate shape of their bones into adulthood, creating a markedly abnormal adult foot structure? Yes.

    Why would the biomechanically-knowledgeable podiatrist not want to offer some form of in-shoe treatment (i.e. pads, pre-made orthoses, or custom orthoses) to a flatfooted child in an attempt to reduce these markedly external and internal forces and moments in the flatfooted child even though the child currently does not complain of pain or discomfort? I can't think of a single reason why the biomechanically-knowledgeable podiatrist would not want to offer some form in-shoe treatment for these children.

    Children that walk and run with abnormal gait function, but have no subjective complaints are, by definition, asymptomatic.

    Flatfooted children without current subjective complaints that have parents who both developed painful flatfoot symptoms as adults are, by definition, asymptomatic.

    Have we now decided, as a medical profession, that we always need subjective complaints (i.e symptoms) to treat markedly abnormal objective findings within the walking and running gait of our patients?

    Have we now decided, as a medical profession, that we always need long term, high-level-evidence research studies to offer a treatment that produces, otherwise, no ill results and makes patients satisfied with the treatment?

    I have no problems treating children without symptoms, in certain cases, who have gait abnormalities or abnormal foot structure and/or with a strong family history of painful flatfoot deformity. If I can offer a child the ability to run and walk with more efficiency and prevent their flatfoot deformity from progressing with either in-shoe padding, pre-made foot orthoses, and/or custom foot orthoses, and not cause any pathologies by doing so, then I feel I have used my knowledge of foot and lower extremity biomechanics and my knowledge of foot orthosis biomechanics to better the life of that child.

    Having the ability to better the lives of my patients is why I became a podiatrist. Increasing the ability of podiatrist to better the lives of their own patients by increasing their knowledge of foot and lower extremity biomechanics and foot orthosis biomechanics is why I have also spent the past 30 years of my life educating podiatrists around the world on foot and lower extremity biomechanics and foot orthosis biomechanics.

    I was not willing, 24 years ago, to let the problem of no long-term research on the medial heel skive technique prevent me from inventing and using the medial heel skive orthosis technique on my own patients and, carefully monitoring them, to see if the medial heel skive technique worked to improve their gait and improve their symptoms as I thought it would. In addition, I am not willing to let children with obvious gait abnormalities go untreated just because the research hasn't been done yet that showed these treatments are very effective at changing gait function. Using these medical ethics, I not only sleep very well at night, but I also have a very busy practice with many, many patient and doctor referrals.

    Time will tell whether I am right or wrong. However, from my view point currently, I have no question about the biomechanical soundness of the way I practice and the treatment decisions I make, or have made over the past 30 years, regarding flatfooted children, whether they are symptomatic.......or asymptomatic.
  5. Rob:

    Even though your article may have received considerable attention in Australia, there is no fuss since very few podiatrists in the US ever read or even knew your article existed. I thought be bringing your article to the attention of a much larger US podiatric audience that some good debate could be stimulated on this interesting subject by the broader US podiatric audience.
  6. Which brings us back to the question, when is a force a pathologic force? Given your contention above, in your view it is when it is "markedly abnormal"; how much force is this? What are the "normal" amounts of external subtalar joint moments?

    Do they always affect the child's ability to walk and run? No.

    Is there any evidence that the bone structure may also spontaneously "correct"? Yes http://www.podiatry-arena.com/podiatry-forum/showthread.php?t=94764

    I guess for a number of reasons, primarily because we have no idea of what pathologic levels of moments are in your context. Another being when you see cases such as the image attached of high quality adult athlete, who is performing at a National standard, who has remained asymptomatic and never had a running related injury despite the fact that he has flat-feet which have never received medical intervention.

    Attached Files:

  7. Might be at my end but images not showing Simon
  8. Seem ok with me.
  9. Petcu Daniel

    Petcu Daniel Active Member

    Also the shoes doesn't seems to be "motion control" and "straight last" type !
  10. Petcu Daniel

    Petcu Daniel Active Member

    Can we reformulate: is it unethical to prescribe foot orthoses to improve the functionality / comfort for children with asymptomatic flatfoot deformity ?

  11. Rob Kidd

    Rob Kidd Well-Known Member

    Sorry to be difficult: how one may improve function in a situation where there is no perceived loss of function by the owner? Surely, a perceived loss of function by the practitioner, where the patient is adamant that there is no symptoms and everything works just fine and dandy does not equal a real loss of function.
  12. The crux of the argument is the determination of all competencies - knowledge, ability, experience - and their application to individual cases, each assessed on their own merit. I don't think it beneficial or helpful to make sweeping statements such as, "it is ethical or unethical to prescribe for xyz condition.... " as it is relatively easy to disprove one way or another and simply lands the professional in difficult waters when litigation lawyers rear their ugly heads.

    I do not have a problem with intervention in asymptomatic flat footed children where the over-riding objective is prevention of symptoms or a further deterioration in the foot structure due to stress or injury of the soft tissues. I would dearly love to include corrective remodelling of the developing foot through serial orthotic management, but I think we are still a long way from realising that particular dream; I don't doubt it may be possible - there is plenty evidence to support tissue remodelling elsewhere, but in practical terms it may prove extremely problematical and would be difficult to tolerate for most children - and the question of ethics is certainly more relevant in progressive intervention than in simple symptom prevention.

    The problem I have is in abilities. There are currently some 14,000 registered podiatrists in the UK of whom I would suggest that <1,000 have a basic biomechanical knowledge of foot function and pathology. Of that, there are probably <40 podiatrists in the UK that I would consider competent to consider intervention for complex foot conditions such as pes valgus, cavus or planus. Acquired foot pathologies such as traumatic injury or invasive/contributory disease such as RA are another area of specialist intervention and again there are few clinicians who would meet the competencies to deliver effective, safe care in these areas. Most of my work this year has been in medico-legal reports and assessments - and it's been an eye-opener, especially where my own profession is concerned. It is not the complex biomech cases that trouble me as much as the very simple lapses in basic clinical practice that are quite incredible and makes me wonder what our colleges are actually teaching podiatry students these days. Reflective practice? I think not. And in a changing health market where other professions are involved in orthotic management of the foot - physios, osteopaths, orthopods and chiropractors - where the knowledge base is arguably far less than in graduate podiatry, I think the predominant focus should be on safeguarding patients as far as possible and try and prevent/restrict practice which is fundamentally unsound. How you achieve this whilst trying to push the boundaries and develop new, effective care - as I'm sure you are doing here, Kevin, is always the greater challenge.
  13. Lawrence Bevan

    Lawrence Bevan Active Member

    Perhaps we needs to distinguish between the presence of "asymptomatic flat foot" and the presence of "asymptomatic pathologic forces". They may be both present in the same individual they may may not.

    It would be potentially ethical to offer to treat "asymptomatic pathologic forces" - not unlike treating asymptomatic hypertension. The presence of flat foot deformity does not guarantee that these forces are present so treating all aymptomatic flatfoot is going to lead to over treatment.

    We need a better predictive model.
  14. Agreed.
  15. Rob Kidd

    Rob Kidd Well-Known Member

    Nice to hear you again Lawrence, after all these very many years - I see you are as reflective as you always were; a very lucid point.
  16. Excellent point, Lawrence. I agree totally.

    I don't treat asymptomatic flatfeet that function in gait relatively normally. I only treat the asymptomatic flatfeet that have significantly abnormal gait function and/or a strong family history of painful adult flatfoot deformity. In other words, I only treat those asymptomatic flatfeet that have sufficiently abnormal magnitudes of external subtalar joint pronation moments [not counterbalanced by sufficient internal subtalar joint supination moments] that causes them to have significantly abnormal gait function.
  17. Orthican

    Orthican Active Member

    Great discussion

    The other point to make is that which is the elephant in the room.
    How do these asymptomatic children end up in our offices?
    The parent.
    And the typical statement of: "My daughter/son has flat feet...that is not normal is it?... can you check and see if she/he needs something in his/her shoes to correct the problem or is there a problem?"
    The denials of any issues with activities from the child leave the parent wondering.
    So in that who is the one getting satisfied here?
    Is there pressure on the practitioner to do something? Anything?
    Where I live that answer is dependant on ethics.
    If there are gait issues I agree with Kevin and I will use preforms and do any additions if needed for a good many of them to keep cost down for the parents as replacement due to growth is ongoing.
    For the others re assurance to the parent becomes the treatment. But I will follow all these kids to maturity anyway to ensure things are not missed that may or may not show up over time.

    Just my 2 c
  18. Kevin

    Can you elaborate specifically on how you treat these children? I assume you use custom moulded rigid or semi rigid devices geared towards reducing the external subtalor joint pronation moments by using whatever combination of prescriptive add ons you consider appropriate for that child. Given that you are applying counter forces to joints that are already severely stressed, tolerance is often a factor and is clearly influential when considering the degree of correction - if I may use that term. The more aggressive the prescription , one assumes the greater risk of precipitating symptomatic injury - which is clearly to be avoided. That said, some may consider that a risk worth taking if those devices increased the possibility of positive structural remodelling or permanent correction. It's an interesting ethical argument.

    I've used rigid, semi-rigid and simple absorbent devices with a variety of prescriptions in the past - some with a progressive serial casting regime - with a variety of outcomes. Very much trail and error, in hindsight. Some of the devices were lab manufactured, some in my garage workshop. How do you measure success? No progression to symptomatic flat foot? Evidence of increased arch height? No injuries? They may manifest with or without intervention. You can't. All you can say is that in your opinion there is a greater chance of injury in this foot type and some of the factors that may cause those injuries may be mitigated by in shoe foot devices. These days I take a fairly simple approach to reducing risk factors and usually supply basic high density EVA insoles which are incredibly absorbent. I don't use the type supplied by the labs or orthotic suppliers - I use a good quality high altitude climbing mat, which aside from being quite inexpensive, more than outperforms anything I've ever used elsewhere. In active kids, the insoles last about a month and they have to cut another pair from a template. A $20 roll of this material will last a child about three years, Tod, so cost is not a huge factor here.. Those children with asymptomatic flat feet that have these insoles have no issues with tolerance or development of symptoms one would associate with this condition. I also haven't seen any notable evidence of remodelling either - except in one child who remarkably had no devices whatsoever and whose flat foot was obviously a developmental issue which corrected itself as he matured. It's a different approach from the custom devices in that I rely on the absorbency of the material to reduce the stress on the foot rather than trying to apply forces directly onto the foot in a counterbalanced way as you would in rigid and semi rigid devices - but it seems to work just as well. The one person I would like to hear from is MASS Ed and whether he has [sic] evidence of good outcomes with his more radical prescriptions.

    I have to say that I am aghast at some of the claims clinicians make to parents when they take their children for consultations and I have no problem suggesting their approach is not only unethical but immoral and probably illegal. There are many Rothbarts in the corrective orthotic therapy division out there and most of them don't have a fecking clue what they are doing and more to the point, probably don't care - as long as the money rolls in. In that respect I think this needs careful discussion so that it may not cited elsewhere as 'evidence' to support practice that is plainly dangerous.

    All the best
  19. Lab Guy

    Lab Guy Well-Known Member

    Excellent post Todd. The parents are very important to consider and I like the idea of a good prefab (that can be modified) to keep costs low.

  20. Mark:

    There are so many permutations of possible patient scenarios I have seen over the past three decades that I don't have time to list them all. However, let me list a couple of examples that better demonstrate my treatment decisions.

    First of all, let's take the example of a 5 year old flatfooted boy brought by the mother because she has been told he needs custom orthoses for his flatfoot condition. The boy does not complain of pain and is, therefore, asymptomatic. The boy runs and keeps up with his peers in sports, doesn't trip, isn't clumsy and doesn't asked to be carried on long walking trips. Both parents have mild flatfoot but are relatively asymptomatic. On physical exam, the boy has a mobile subtalar joint (STJ) with slightly increased range of motion, has mild medial deviation of the STJ axis, and has a mild flatfoot deformity. He walks with good resupination in late stance and runs normally for his age. In this child, I recommend no treatment but advise the mother that if the boy starts to develop symptoms due to activities, to bring him in again for me to reexamine him as to whether he needs to be treated with some form of foot orthosis therapy.

    Next, let's take another example of a 5 year old flatfooted boy brought in by the mother for his flatfoot condition. The boy doesn't ever complain of foot and lower extremity pain and is, therefore, asymptomatic. However, the mother notices he asks to be carried on longer walking trips and notices the boy seems to run "funny" compared to his peers. The mother also states that her son tends to not want to play sports with the other boys and girls his age. Both parents have moderate flatfoot deformities and both have had painful feet and ankles beginning in their late teen years. On physical exam, the boy has moderate medial deviation of the STJ axis, and has a moderate flatfoot deformity. He walks with a maximally pronated STJ throughout the stance phase of gait and has a relatively apropulsive walking gait with little resupination during propulsion. He runs with short strides, an abducted gait and pronates excessively during the midsupport phase of running. In this child, I will recommend custom foot orthoses made with 3-4 mm polypropylene, with 18 mm heel cups, with a 4-6 mm medial heel skive, and minimal medial arch fill. If the parent can't afford custom foot orthoses, I will either fashion an in-shoe medial heel and medial longitudinal arch support out of multiple layers of adhesive felt (see drawing below) inside their shoe or recommend a pre-made foot orthosis that I can modify for the child. In most cases, once the mother sees the improvements in her child's ability to walk long distances and better keep up with his peers in sports with improved ability to run, they become anxious to have their child placed into custom foot orthoses rather than in-shoe padding or pre-made foot orthoses due to fact that even to their untrained eye, my biomechanical treatment has made a significant difference in their child's life.

    I would be happy to provide treatment plans for other similar patients if you are willing to take the time to present them to me in detail here within this thread.
  21. No that's great, thanks. I just wanted to clarify what you were doing. We share the same principles on intervention and treatment; I just take a different approach on how to reduce the external forces acting on the foot by increasing the absorbency of the material rather than trying to interfere with foot function and it seems to work just as well. What is also an advantage is that if you have the patient return the insoles after 4 weeks you get an extremely good impression on the material which is always helpful in considering modifications - but it's the absorbency that's the real key in their success.
  22. Mark:

    What do you mean by "absorbency of the material"? Moisture absorbance, shock absorbance, sound absorbance, light absorbance....which one is it? If it is shock absorbancy you are talking about, please use the more clear and precise terms of material durometer or material stiffness so we can all know what you are talking about.
  23. I can't provide the latter presently but would suggest it is force/impact absorbency as opposed to shock absorbency which implies a single instance attenuation. For high impact sports where shock absorption is indicated, I would tend to use sorbothane or poron due to it's rapid reformation rate; but this EVA works differently and will readily deform after a relatively short period - 4-6 weeks and 'bottom out' after 6-8 weeks - but it appears to have a different therapeutic effect than either the closed cell PU or any other material I have used. It is also excellent in managing atrophic conditions of the plantar plate, RA and calcaneal bursitis and is one of the few materials I have used that successfully clears chronic plantar pressure HDs in a 12 month timeframe. If my name was Dennis it would have a patent on it by now. I'll speak to the manufacturer and get some technical specifications when I am vertical again - and I'll send some in the post for you to try.


    Attached Files:

  24. I've been thinking about this today. We have a situation in which the bones are remodelled in accordance with Wolff's law. So the bones change form in response to the forces being applied to them- right? Surely the body "knows" what it is doing here and is redesigning with a purpose and a plan, not just randomly- this is a mechanism which has been evolved over a very, very long period of time and as such it must provide an advantage; its not going to remodel the bones to make the structure weaker to the applied forces, rather it is going to make the structure better suited to the forces being applied to it. If the body "knows" what it is doing, how can we say that this process results in an "abnormal foot structure"? Surely the structure the body remodels the foot to is the best design it can provide for the forces being applied to it?

    I guess it's a hangover from Root, these terms "normal" versus "abnormal" still keep cropping up in our discussions. If we are going to use them, we really should be able to define them.
  25. I don't know how much the body "knows" how to remodel the foot and/or lower extremity in the most efficient and/or least injurious pattern. Rather, it is, I believe, more accurate to state that the body remodels directly in response to the stresses acting on it and within it over time.

    For example, in the development of medial knee osteoarthritis, a progressive varus deformity of the knee develops in response to excessive loading forces acting on the medial compartment of the knee. If the body "knew" this was happening, then it would add more bone length to the medial femur or medial tibia to prevent this frontal plane angular deformity within the knee from occurring over time.

    Rather, we know that what occurs in medial knee osteoarthritis is that the increased compression stresses in the medial compartment of the knee gradually thins the medial compartment knee cartilage, gradually increasing the genu varum deformity, which in turn, further increases the compression stresses within the medial knee cartilage, which over time leads to a bone-on-bone situation within the medial compartment of the knee (Maquet, Paul G.J.: Biomechanics of the Knee. Springer-Verlag, New York, 1984). If the body had "knowledge" that this was happening, why didn't it prevent this frontal plane angular deformity of the knee over time from occurring by remodelling itself to prevent the genu varum deformity from increasing in deformity?

    Answer? The body doesn't remodel in response to some innate intelligence within each structural component (i.e. bone, ligament, tendon, skin, cartilage, muscle, and fascia) of the musculoskeletal system. Rather each and every structural components of the body is viscoelastic in nature. In other words, each and every structural component of the body will remodel in response to the magnitude, duration and loading rate of tension, compression, shearing and bending stresses acting on it over time. This is the time-dependent load/deformation mechanical nature of biologic viscoelastic structures: they will change shape over time if the forces acting on them are great enough and the duration of force application is long enough.

  26. Interesting. Here's some of the things that published research has said about the bone changes at the knee in O/A, see image attached from the book: Advances in MRI of the knee for osteoarthritis by Sharmila Majumdar, ‎2010. It seems that malalignement of the knee due to cartilage degeneration is associated with bone formation in the diseased condyle and bone reabsorption in the opposite condyle, in other words the body does add bone to the medial femur in medial O/A, Kevin. It doesn't necessarilly make it longer, but it does make it stronger which sounds like a reasonable plan. Now, what occurs to the bone morphology in paediatric flat-foot?

    BTW, the inherent intelligence is called "evolution", which is why bone is deposited to areas of high loading as opposed to being reabsorbed in the areas of increased loading: this provided an evolutionary advantage at some stage which is why we see it today.

    Here is another paper on bone mechanics that some following along may find useful.

    Attached Files:

  27. Just remembered where I've read this before; first year notes, Edinburgh Foot Clinic 1980. Corns - aetiology (Jack Ellis) - haven't we come a long way since then...:empathy:
  28. Just as saying corns are a response to the mechanical loading of the skin may be true from a rather naive first-year undergraduate perspective, the actual mechanism by which bone remodelling occurs is somewhat more complex than a statement such as "biologic viscoelastic structures will change shape over time if the forces acting on them are great enough and the duration of force application is long enough" implies. The actual cellular processes of bone remodelling and for that matter corn formation, are far more complex than this statement suggests because we are not just talking about inducing plastic set here.

    For example, how do the osteocytes detect changes in the forces applied to the bone and translate them into biological signals required to initiate bone remodeling?

    Why does a callus turn into a corn? etc.

    This might help with the first question: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2919071/

    The authors here state that the osteocytes "sense" changes in the physical forces- how do the cells "sense" changes?

    Going back to the earlier point about medial knee O/A, it's actually a kinematics versus kinetics argument, Kevin. You suggest a kinematic solution in that you believe the medial femur should lengthen in order to change the position of the knee, whereas what the body actually does is to provide a kinetic solution by increasing the medial femurs ability to withstand the load. So back to asymptomatic paediatric flat-foot: the body will remodel the foot bones, increasing their strength in the areas of highest physical loading such that they are better adapted to withstand the loading being applied to them as a result of the foots position. This has to be correct because we know that this is what bone does- agreed?
  29. I don't doubt that bone reacts differently to skin under sustained force and clearly the cellular mechanisms that influence and adapt the changes you illustrate are different too. It's not a new or naive concept by any means. Bone changes manifest in many different ways too depending on systemic, immunological as well as biomechanical factors. Just like skin - the principles of tissues subjected to pathology are the same and what Kevin refers to, if I'm not mistaken. I'm not convinced by the "intelligence" claim or by the implied description, even accepting that some bone cells have a sensory element to their function that precipitates cellular changes although it is curious when paediatric flat feet undergo spontaneous correction - or remodelling - without any intervention by external means.
  30. Ian Drakard

    Ian Drakard Active Member

    But does the fact we're dealing with a paediatric population change this? If there are open growth centres will there be a kinematic change also as well as a change to the trabeculae to withstand loading?
  31. Let's be clear on the "intelligence" thing, Kevin used this term initially, not me. I used the term "knows", I chose this term and put the quotation marks around it to indicate that this term was being used loosely and for want of a better term, since as stated here:http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2919071/ "The current physiological bone-remodeling paradigm is incomplete" if you didn't get that then it's unfortunate. In terms of this though, if we argued that much of the body systems are ultimately controlled via the brain, we could then also argue that such systems are under the control of an intelligence of sorts, at least in some individuals. But really, "knows" was just a throw away term to describe the interaction between the body systems that result in bone-remodelling in the manner that is observed in-vivo in response to mechanical loading, i.e. the bone is strengthend where the high forces are by cellular activity as oppossed to cellular activity decreasing the strength where the high forces are, which strikes me as the intelligent thing to do.

    The remodelling is the important bit here, so lets not loose track of that. The point is that the body is capable of responding to loading by remodelling and thereby modulating the strength of the tissues such that they are capable of withstanding that loading and it's interaction with the kinematic system without the tissues ever reaching pathologic levels, so why do you want to put an orthosis in the shoe of an asymptomatic child with flat-foot when the fact that the child is asymptomatic tells us that the body is managing this process quite nicely, thank you very much for asking?
  32. That might be ok at a given point in time, perhaps even when the child and their parents consult with you and ask your advice. I'm not sure on reflection I like the term remodelling either as again it could easily be misconstrued or abused; it suggests a change in the bone structure - which you suggest is a positive thing as it strengthens the tissues under load. Ok that's fine too and if the changes were to lead to a structural shift in the abnormality to a more "normal" arched foot, that would be positive, but that is rarely the case. The changes in the bone structure you allude may very well strengthen the bone in the area under stress but over a period of time will usually lead to the usual range of acquired secondary joint and tissue abnormalities associated with chronic pes planus - and that surely has to be a consideration you give to the parents. The body may be managing the process of dealing with tissue damage in the developing foot quite nicely and the changes tolerable, but that's short term thinking and most of my parents have their eyes on the future and mitigating pathological risk - even though it may not be apparent at the time.
  33. And there we are viewing the foot through the lens of a very old paradigm- what is a "normal" arched foot (Feiss realised there was no such thing in 1909), why is a low arch seen as an "abnormality" and why does the foot need to meet an aesthetic expectation in it's structure if the tissues are all functioning within their zones of optimal stress?

    See above.

    N.B. Not all flat feet become symptomatic ~I'll grab a photo of an elderly patient of mine next time she is in, her only symptoms come from a corn on the end of one of her toes, despite the fact that she walks around with her navicular bones on the floor- never had plantar fasciitis, PT pain etc etc, nothing but the corn on her mallet toe.

    Question: why does an asymptomatic flat-foot become a symptomatic flat-foot? What has to change?
  34. Note the quotation marks, Simon, and your previous remarks. How do you know the tissues are functioning under their zones of optimal stress? Because the foot is asymptomatic? Is that an accurate measurement? Perhaps this child has a high pain threshold or exhibits a robust response to injury but goes on to develop pathological foot and lower extremity secondary joint problems that could still be "asymptomatic" or pain free in later life, but may impact in other ways, such as mobility. It's a judgement call; you look at the severely flat footed child in front of you who may not complain of any symptoms presently and his mum asks you is everything going to be ok? And you say:
    Bollocks. The tissues may well be functioning in your "zone of optimal stress" but the long term implications for the patient are not always favourable.
    Of course, we all have patients like that and you wonder just how the heck they've managed; same with RA patients when you look at the bag of broken candy that masquerades as their foot bones on x-rays. People do; it could well be that the "changes" in response to local injury have systemic implications too, perhaps in pain tolerance and that's why such a large number of severely deformed flat footed adults remain relatively asymptomatic throughout life. Does it impact on function; does your "aesthetically desirable higher arched normal profile" foot perform better? I would have thought so, but how do you measure performance? Back to the asymptomatic -v- symptomatic argument again? If that is your only consideration, you're failing your patient.

  35. So, what is it that you meant when you said "normal" arched foot?
    Yes, because they are asymptomatic.
    Or maybe they don't and won't.

    No, what I actually do is relate what the evidence base- from anecdote through to controlled trial tells us about their childs feet and allow them to make an informed decision about how they wish to proceed with their childs care. Is this ethical?

    And sometimes they are, how do you spot the differences?

    It's more likely the level of stress, but the threshold may change in response to the level of stress, here are a couple of slides which show the relationship between loading and threshold- what does this tell us? Lets take the deltoid ligament in a child with asymptomatic flat-foot and think about the adaptation process that will occur in this tissue under loading and over time...

    Attached Files:

  36. I'm sure you can apply some imagination to that one.

    But undergoing change or remodelling which may not be desirable, despite increased tolerance to the stress.

    That entirely depends on your interpretation of the evidence and what weight you put on the view that these changes are "normal" and we should not intervene in that process.
    Time and a good memory. The real question is that if you accept that this remodelling process can lead to undesirable arthritic joint problems in chronic flat foot, why would you not try and mitigate these changes?
  37. That's the key- the remodelling has to be desirable because the body increases the strength in the tissues where the load is highest, which elevates the tissue thresholds... and that's the point. Viz, the body "knows" what it's doing and getting it right in these asymptomatic individuals:drinks
  38. That aspect may be desirable; for a variable length of time - it may strengthen the bone and prevent pathological fractures or limit erosions initially but that can never be the only consideration. Let's change the tissue and patient. Take your average coke-head who sticks a few grams of Columbia's finest up their nostrils every weekend. Not a big problem initially; you may see cellular changes - increased hyperaemia and a proliferation in the microvascular network in the septum and a thickening of the nasal sill but most of the time the tissues recover then adapt - much in the same way as your bone remodelling theory - and the localised cellular response becomes more tolerant each time the powder goes north. But there is still damage being inflicted and that can lead to chronic symptoms including the formation of bone sequestra, necrosis and eventual septum rupture - but not always. Some coke-heads manage to keep it together, physically and mentally, for much of their lives, but they're a rare breed. The question is, as clinicians and knowing what we know, should we intervene in an attempt to prevent potential chronic damage, even though what we might be seeing presently is tissue adapting within its usual function to whatever external forces it is exposed to? In asymptomatic flat feet, of course.

    This bloke brings his five-year-old son to see you. Family history of flat feet. Asymptomatic - the kid has no problems or complaints. Dad asks "Is there anything to (a) worry about or (b) that you can do to prevent them going like mine - and what might happen to mine in another thirty years?" You say?

    Attached Files:

  39. Amongst other things I ask him why he doesn't want his son to have feet like his, tell him the truth regarding the evidence base and that I don't have a crystal ball at hand to predict either of their futures; you clearly do have the powers of divination to predict the future uncertain though Mark so good luck with that. Do you have any photographs of the feet post orthotic intervention which show both of them with "normal" arched feet?

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