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Prescription writing for foot orthoses

Discussion in 'Biomechanics, Sports and Foot orthoses' started by Simon Spooner, Dec 26, 2007.


I believe that I can scientifically rationalize the angulation of extrinsic rearfoot posts

  1. Agree

    4 vote(s)
  2. Disagree

    37 vote(s)

  1. Members do not see these Ads. Sign Up.
    The thread on orthoses here:
    has got me thinking again about orthoses prescription writing within the tissue stress paradigm. Given our current knowledge base, if you were designing a prescription form for foot orthoses what categories would you include, and why?:boxing:
  2. efuller

    efuller MVP

    The "why?" part of your question is very important. Each measurement should lead to a potential change in orthosis design.

    I include

    Medial Arch height standing relaxed. (An attempt to get the arch height close to right. Too high hurts. Too low patients start asking questions about custom. In my opinion some pressure in arch leads to more resupination in gait.

    Plantar fascial groove?

    Maximum eversion height > whether or not to include intrinsic forefoot valgus post.

    STJ axis transverse plane position > medial or lateral heel skive

    Structure that needs reduction in stress

    Forefoot extension

    Standing heel width > amount of lateral expansion to add to NWB cast

    Met cookie in cast.

    Anybody use anything else?

  3. In the prescription orthosis order form for Precision Intricast, we include options for orthosis material type, orthosis thickness, rearfoot post angle and motion, heel cup depth, added heel height, topcover materials and length, forefoot extension material, forefoot accommodations and wedges, balancing position, medial and lateral heel skives and many other permutations on orthosis design. Why do we feel we need all of these options? To optimize the ability of the prescribing clinician to custom-design their patient's foot orthoses.
    Last edited: Dec 27, 2007
  4. efuller

    efuller MVP

    I left out posts, lifts and top cover material
  5. scottma

    scottma Member

    Dear Dr.Fuller:
    I do'nt understand why podiatry does'nt borrow some techniques from dentistry to incorporate into clinical practice? In dentistry, we use pressure indicating paste( PIP) to disclose pressure spot. In this way, we can precisely locate the pressure spot and relieve it by selective grinding instead of by patient identifacation, which is much less precise. BTW, I am a senior practising dentist, specialized in Temporomandibular Disorder, occlusion,and restorative dentistry. I graduated in 1983. Commercially available PIP from dental supplier is very expensive. However, you can make your own PIP by mixing Zinc Oxide powder and vegetable oil, whatever consistency of paste can be adjusted by POwder/Liquid ratio. and it is easy to clean up. One thing I am not sure, is polypropylene as easily ground as dental acrylic resin? Another thing I do'nt understand is , the word " tolerate" is frequently used in regard to delivery of foot orthosis. To me, tolerate implies discomfort or some minor degree of pain. Forgive me if I misunderstand the word tolerate. English is my second language. You probably can tell from my writings. Complete dentures ( full dentures) have some similarities to foot orthosis. Complete dentures are arificial teeth fabricated for those who do'nt have teeth at all. Well fabricated complete dentures do'nt require patients to tolerate. Is it possible that patients can have comfortable foot orthosis after meticulous adjustment in stead of tolerating?
    Scott Ma, D.D.S
  6. Craig Payne

    Craig Payne Moderator

    Limited time to post, but here are my initial two reponses:
    Does not this first law some up the approach of many to orthotic prescription decision making.

    Sacket's definition of evidence based practice:
    This should sum up how it should happen.
  7. Aren't posts just a throw-back to Rootian models and a reflection of the available manufacturing technology of the time? Why are posts and moreover, posting angles still important?
  8. efuller

    efuller MVP

    This is a classic example of someone seeing something work and then trying to come up with an explanation of why it works. I disagree with the Rootian explanation of why posts work, but correctly prescribed they do work.

    There is a marked difference between a patient stepping on (out of the shoe) a device with a medial heel skive with no rearfoot post and a device with a rearfoot post. The non posted device will flex significantly more. A rearfoot post will change the rigidity of the finished device. I predict that a rearfoot posted medial heel skived orthosis will increase pressure under the medial heel. I also predict that this will alter the location of the center of pressure in the contact period of gait.

    One of the most gratifying patients is the one with a peroneal tendonitis who you put a forefoot valgus wedge underneath. They notice the difference immediately. This can be done with adhesive felt or an orthosis. An intrinsically posted forefoot valgus device will have a forefoot valgus wedge effect because the intrinsic post does make the the point at which the fifth metatarsal rests higher off of the ground. When someone stands on this device they will stand in a more pronated position unless their posterior tibial muscle is active. I also predict that there will be less EMG activity of the peroneal muscles espeicially those who use their peroneal muscles in static stance.

    The forefoot valgus posting angle is relevant because when too much forefoot valgus post is added you may get sinus tarsi pain or too much force on the lateral column because the foot cannot evert far enough to get weight on to the medial forefoot without moving the tibia. Prediction: Measure maximum eversion height and then place a wedge under the lateral forefoot that is 3mm higher than the maximum eversion height and those subjects with adequate sensation will remove them as they will be uncomfortable for some reason. (When I've done this to my orthoses I get sinus tarsi pain.)

    The prescription writing protocol taught by John Weed in 1985 was complex, but a major part of it could be boiled down to not evert the foot farther than it could go. He realized that the concept was important, so some of the Rootian (Weedian?) principles were important.

    There are the predictions and I'll let someone else do the study.


    Eric Fuller
    Last edited: Dec 27, 2007
  9. I agree with you here, Eric. Rearfoot posts are an important part of foot orthoses in those patients where medial and/or lateral heel skives are being used. I use a flat rearfoot post when I am using a lateral heel skive to avoid the loss of orthosis contact in the lateral rearfoot post with the shoe for this reason. Not using a rearfoot post in these cases will significantly decrease the clinical effectiveness of the orthosis at either increasing or decreasing external subtalar joint pronation/supination moments.

    I will also often add, in these patients with peroneal tendinopathy, a piece of adhesive felt or korex plantar to the lateral arch of the orthosis to increase the stiffness and prevent deformation of the lateral orthosis arch, in order to increase the external subtalar joint pronation moment from the orthosis and help relieve the peroneal muscle/tendon symptoms. I don't know necessarily that they will be "more pronated" with this device, but certainly, I would expect the EMG activity of the peroneals to be lessened using this modification.

    Sounds like a good research project!: seeing whether EMG activity of the peroneals increases as the subtalar joint axis becomes more laterally deviated during standing and walking compared to those individuals with more normal subtalar joint axis location and seeing whether this increased EMG activity in those patients with lateral subtalar joint axis deviation decreases with rearfoot and forefoot valgus wedging.
  10. Love it:D:good:

    Tell us oh wise guru, what are the rest of paynes laws?

  11. Craig Payne

    Craig Payne Moderator

    There are only two laws. The one above and this one:

    Payne's Second Law
    "The more poorly something is understood, the more theories there will be about it"
  12. Dean Hartley

    Dean Hartley Active Member

    Eric can I ask how you determine how many degrees of posting you add to the orthotic?
    You were saying how you do not agree with the explanation given by the way Rootian posting works, I assume you are referring to 'X-amount of degrees resulting in X-amount of correction.' (I greatly simplified this).

    I would gather you aim to change the centre of pressure using these posts to alter the external forces of the subtalar joint..? Could I ask how you come to your prescription for how many degrees of rearfoot posting from your clinical exams? I understand the force of STJ resupination would play a pivitol role in this as well. I would think a huge proportion of this answer would come from clinical experience, knowing when to use either 4,6 or 8 degrees of correction on a certain patient.

    I hope this made some sense and reference to what I was trying to ask.

  13. efuller

    efuller MVP

    Hi Dean,

    I will assume you have knowledge of Rootian cast correction methods.

    Fore forefoot valgus posting I use a measurement that I call maximum eversion height (MEH). With the patient standing in angle and base of gait, I ask the patient to evert their foot. (May require some explanation/ demonstration and the rare patient cannot figure it out.) Then observe the height of the lateral forefoot off of the ground. Some people cannot lift their lateral forefoot off of the ground because of lack of range of motion. Those with MEH of zero do not get forefoot valgus wedges as any attempt to lift the lateral forefoot off of the ground will usually hurt. An additional test is one described by John Weed and that is to place the fingers under the lateral forefoot. Those with MEH of zero will hurt your fingers. As an aside, feet that supinate easily may also hurt your fingers, but they may have an MEH of over 3mm.

    Anyway, I usually add a forefoot valgus intrinsic post not measured in degrees, but measured in mm. The amount of post should never be higher than the MEH.

    I never use forefoot varus intrinsic post as all they do is increase the medial arch height. Usually you can use less arch fill if you want to increase medial arch height.

    For the rearfoot, there are two things to pay attention to. One is the shape of the heel cup and the other is extrinsic post applied under the heel cup of the orthosis. The decision of the shape is determined by my assessment of the transverse plane projection of the STJ axis. (See Kevin's paper on finding the location of the aixs.) I grade these as very medially deviated, medially deviated, avg, laterally deviated and very laterally deviated. Those with medially deviated STJ axes get medial heel skives (more skive with more deviation) and those with laterally deviated STJ axes get lateral heel skives. The skive decision is also partly based on patient symptoms.

    I usually add extrinsic rearfoot posts when I add a skive. If there is no skive I usually do not add a post because there are fewer shoe fitting problems.

    The above protocol is independent of the forefoot to rearfoot measurement seen in the cast. Even if you have a forefoot varus in your cast you can still add a forefoot valgus intrinsic post and then shape the heel with a skive. (I don't always do a skive, but I sometimes add plantar expansion plaster on one side to change the shape of the heel cup. Skiving can reduce arch height.

    That's the basics and there are exceptions. I hope that answered your question.


  14. What are we trying to achieve when we add our rearfoot posts? A re-positioning of the centre of pressure? Eric intimated that he uses posts to stiffen the device, is this what we want from the post? Or is just a case of stopping the device from rocking in the shoe? How else might the same goals be achieved?

    Where does the rearfoot posting angle come in? If I were a novice, fresh out of podiatry school and presented with a lab prescription form, containing the items that have been listed previously, how do I decide on the rearfoot posting angle? How do I decide what angle or how deep a skive is required?

    How many quesions I can fit in one post?:drinks
  15. Dean Hartley

    Dean Hartley Active Member

    Thankyou for your reply Eric. Adding further to this could you tell me how you come to your rearfoot posting angle?
  16. Dean Hartley

    Dean Hartley Active Member

    Yes they were actually my next question/s? Could you or anyone shed any light on this?

  17. Scorpio622

    Scorpio622 Active Member

    It depends on the size of the post, and whether it is intrinsic or extrinsic. :deadhorse:

    Sorry, I couldn't resist. :dizzy:

    Seriously though.... I think the number is arbitrary considering the margins of error that exist along the way. First, the clinician arrives at a desired number of degrees based on the clinical exam- this carries a few degrees of potential error. Next, the cast is taken with potential error of forefoot to rearfoot relationship. Then the positive is poured and "balanced"- more potential error. Next the posting is applied- more potential error. And let's not forget the shoe- there differences in heel angulation (either intentional- motion control running shoes, or unintentional- lateral heel wear).

    Trying to titrate the post angle within a single degree seems like wishful thinking. The lab I use tends to underpost, so I routinely ask for 6 degrees and get what looks like 4. The exact number is a mystery but the patients get better. Would specifying the posting angle as mild, moderate, or high make things clearer for the lab and students ???

  18. efuller

    efuller MVP

    I do believe that we are trying to change the center of pressure. I have modified the rearfoot post under my orthoses and I can tell you that I can feel the difference. The modification was to add varying amounts of varus wedge to the bottom of a flat post. At higher angles I could feel fatigue in my peroneus brevis muscle. Simon, I realize that you did a study that did not really find much difference in center of pressure, but you have to tie together the "cognitive" response with the change in wedge under the foot. A subject could alter their touchdown angle to achieve a similar center of pressure location. So an EMG measurement should be done at the same time as the attempt to change the location of center of pressure to have a really conclusive study.

    A stiffer device should shift center of pressure more. We have to carefully define what we mean by posting angle. What I am talking about is the relative height of the medial and lateral side of the heel cup when the rearfoot post of the orthosis is resting on a flat surface. This should correlate with the amount of skive in the cast. This is different from the bevels on the bottom of the post. I believe that our accuracy in measuring STJ axis position is such that grouping people into 5 groups as I described in post 13 above is about all we can do. If the "correction" is not right then the rearfoot post can have a wedge added after the fact.

    It certainly is best for me if I estimate the correct amount of "correction" the first time, because everyone is happy. What separates the good biomechanists from the great ones is altering the device that does not fully relieve the patient's symptoms to the point where it does relieve the patient's symptoms. John Weed talked about going back and finding the error when an orthosis was not working. If you change anything you have a chance of making it work better. This is why I like the tissue stress approach to orthotic therapy. Using this approach gives you insight into what changes you should make. You give a patient with sinus tarsi pain a 2mm skive device and their symptoms are only partially relieved. Well, I would add a varus wedge on the bottom of the rearfoot post (Amongst other things) to try and increase the supination moment from the ground.

    Regarding grinding angles in the bottom of the post the difference between no grind and a 4 degree grind is probably so small that it does not matter. On the other hand if you put the post on the medial side only that might be significantly different from a flat post in shifting center of pressure.


    Eric Fuller
  19. Agreed, but surely the real trick is understanding the effect on joint moments. To know this we need to have a knowledge of the spatial location of the joint axis.

    Uniformly stiffer? If this is what you mean, can you explain the physics of this please?

    Are you assuming here that the heel cup itself is uniform height on medial and lateral sides and hasn't been ground down to differing heights?

    So why do you think the 4 degree post is so commonly requested by clinicians?
  20. But why choose 6 degrees? Why do we seem to choose equal numbers?

    I'm trying to play devil's advocate here and to look at this as if I had no previous knowledge of the subject. A patient walks in with condition X which is associated with increased stress in tissue Y which resists pronation, how do I decide whether I need to use a skive or an external post; upon the depth/ angulation of the skive or the angle of the rearfoot post?

    Imagine you are trying to teach this to someone to whom you must justify the process. Are we, some of the finest minds in podiatry, saying that we use guess-work, all be it educated guess-work (guess work, is still guess work, no matter how we justify it)?
  21. Craig Payne

    Craig Payne Moderator

    Traditionally, I posted the rearfoot to the angle of the measured neutral calcaneal stance position (NCSP) as that was the position we assumed we wanted the foot to be in at mid-stance. SO, there was a rationale for the posting angle (a rationale we now know to be flawed).

    Now we know that an orthotic posted that way is really good at holding the positive cast model (inanimate object) in that position, but not the foot (biological structure) when standing on the posted orthotic.

    Now we also know that posting the rearfoot to NCSP (or whatever position), is not related to clinical outcomes.
  22. So, with this knowledge in mind, what do we now do? I suspect the point we are all skirting around is that now there is no rationale what so ever- think of a reasonable number between 0-15ish? So this again begs the question are they even necessary?
  23. I've spoken about this before with Dave Smith, but it seems relevant here in our discussions on the merits of rearfoot posts. I went for a walk over Dartmoor today and was confronted with a wide variety terrain; variation in the surface geometry and stiffness if you like. How does adding an angled wedge under my foot, in the form of a rearfoot post on my orthoses, make any significant differences given the variations in the inclines and compliance of the surface I am walking on? Obviously I get surface geometry angle + stiffness+ post angle in this environment, whereas on the flat indoors I get horizontal + stiffness+ post. Given that the devices work in a flat environment, why should they still work in an uneven environment? Alternatively, why should surface geometry + orthotic always = therapeutic success? Why should they work independently of surface stffness? The more I think about this, the less I understand about foot orthoses...:bash:
  24. efuller

    efuller MVP

    Happy New Year, Simon,


    I was thinking of just the heel cup. A heel cup with a wedge effect in it will be stiffer with a rearfoot post. When the heel of the foot steps on the orthosis the posted orthosis can push back harder and earlier compared to the orhtotic without a post.

    What I am referring to the effect of the medial heel skive. As you look at cross section of the orthosis in the frontal plane, measure in 1/3 of the total width from each side. At those points there will be a wedge effect when one side has a greater height off of the ground.

    Well, the orignal explanation was to allow 4 degrees of motion. This had the implied assumption that the foot would move the exact same amount as the orthosis. Now there, is an interesting survey. Ask podiatrists who use 4 degree motion posts why they do. I wonder what percentage of podiatrists could tell you why they do it. Call me cynical, but I believe a lot of people do what they do because that's what they were taught to do. :morning:

    I've written my rant before about the logic of the 4 degree motion post. The impression of the post in the shoe will not allow motion and the shoe hits the ground inverted. There is no reason to believe that a post angle will have any correlation with the motion observed.


  25. Just because there are a few research studies that show that treatment of individuals with foot orthoses with rearfoot posts did not significantly affect clinical outcomes does not also mean that rearfoot posts are not an important factor, and possibly a critical factor in producing successful orthosis outcomes in many patients. There is no question in my mind that rearfoot posts are a necessary part of many shank independent orthoses in order to optimize the clinical results from the orthoses. Rearfoot posts stabilize the orthosis within the frontal plane, rearfoot posts affect the rearfoot moments during the contact phase of gait, and rearfoot posts provide increased stiffness to the longitudinal arches of shank independent orthoses. They are not necessary or even desired in all foot orthosis applications, but I use them in about 90% of my patients' foot orthoses. If you are prescribing a medial heel skive or lateral heel skive without a rearfoot post in an orthosis, then you may as well not even do the skive in the first place due to the increased frontal plane bending of the rearfoot to the forefoot that will occur within the orthosis shell without the stabilizing effect of a rearfoot post. If you are never using rearfoot posts in shank independent orthoses, then you are losing probably 1/3rd of the therapeutic benefit of foot orthoses in many patients.

    Posting angles such as a "4 degree varus rearfoot post with 4 degrees of motion" are probably not that important in today's softer soled shoes. However, I believe at the time rearfoot posts were created at CCPM, in the late 1960's, posting angle and motion were probably much more critical due to the predominance of harder soled shoes. I was taught by both John Weed and Mert Root to change the amount of rearfoot post motion depending on the inclination angle of the subtalar joint axis (increase the motion with a lower pitched axis and decrease the motion with a higher pitched axis). They both claimed that they had made small changes in rearfoot post motion to the benefit of some of their patients by observing and adjusting for subtalar joint inclination angle. Even though I haven't found the need to change rearfoot motion for many patients, I am practicing in a different era of shoe durometers than what my biomechanics professors, Dr. Root and Dr. Weed, did.

    By the way, Ed Glaser's lab, Sole Supports, also doesn't use rearfoot posts on their lab's orthoses. Maybe some of you also want to follow Dr. Glaser's example of not using rearfoot posts on your orthoses??:rolleyes:
  26. Agreed. Are there any research studies which do show that the addition of a rearfoot post did significantly affect clinical outcomes?

    Again I agree. But do the posts need to angled to achieve these effects? Indeed, could some/ all of these effects be achieved by alternative methods?

    When don't you use them?

    This is the real key to what I wanted us to explore in this thread. What angle of rearfoot post is important for todays footwear and moreover, how do we determine it? Eric has suggested that he doesn't think that a 4 degree post is any more effective than a 0 degree stabilizer added to the shell. So how do we arrive at that "magic" number?
  27. pgcarter

    pgcarter Well-Known Member

    Great ideas here, very interesting. I agree with what Simon says about variable terrain+shoe+orthoses being an equation that seems to make a mockery of small orthoses prescription variables......but....what about the idea of the foot having an ability to interact with external surfaces and forces that is either less or more intrinsically efficient and or stable, strong, resistant....or any other fairly unscientific descriptive words....and that it is this ability to act, react, exert or absorb force or forces in non-injurious ways that is being influenced by what we do....too many variables to isolate and discuss them all here....but what happens when you take an intrinsically lax midfoot, park it on top of a fair sized cuboid notch or lateral column support in a shoe....the whole midfoot begins to behave differently...more rigidly....can't prove it scientifically....but I think I'm seeing it. Not trying to be specific here but floating an idea, looking for feed back.
    regards Phill Carter
  28. The lack of responses regarding how we arrive at the "magic number" for our rearfoot posting angles has not only re-affirmed a belief I have had for some time, but also got me thinking about an interesting little vox pops which could possibly be the basis of a publication. I'd like to add a poll to this thread like Craig did in his thread on becoming Australian. Something along the lines of:

    I believe that I can scientifically rationalize the angulation of extrinsic rearfoot posting I prescribe for foot orthoses: Agree, Disagree

    Can you help please Craig?

    P.S. this should probably be added as a new thread so we can see how many people read it versus how many respond to the poll. Obviously anyone who hits the agree button should be expected to explain their rationale.
    Last edited by a moderator: Jan 4, 2008
  29. The 4 degree rearfoot posting angle was arbitrarily set at this amount by Drs. Root and Weed since it was believed at the time that 4 degrees of rearfoot motion was the amount of frontal plane motion needed by the rearfoot to ensure normal gait function. This number seems to have worked well for about 8,000 of my patients over the past 22+ years in their orthoses. Rich Blake has been flat-posting (i.e. no rearfoot motion) nearly all of his patient's orthoses for the past 20+ years. You can even just leave off the rearfoot post sometimes and have a nicely functioning foot orthosis.

    While your asking the question about the scientific rationalization of the angulation of rearfoot posts, why not ask also about the scientific rationalization of all foot orthosis design parameters? Until we have the research to inform us regarding the clinical effectiveness of all orthosis design parameters, the opinions of clinicians as to the effectiveness of these design parameters will always be just.....educated guesses.
  30. efuller

    efuller MVP

    Hi Kevin,

    So is your point that it does not matter? My opinion is that it might matter a little bit. Chris Smith, one of Kevin's and My professors, used to say that they ground the post after finding out the patient had STJ pain. The rationale was that the flat post limited motion too much and that caused the pain. My guess is that patients were getting sinus tarsi pain and the grinding of the post could lessen the pronation moment a bit. There might not be much difference between a 4/4 post and a flat post, but I think I can feel the difference between medial only post and a flat post. It's been a while since I tried that on my own devices. I'll have to go try again.


  31. admin

    admin Administrator Staff Member

    Last edited: Jan 4, 2008
  32. Many thanks. But it says "I ... extrinsic rearfoot". Could you add the word posts to the end please?
  33. admin

    admin Administrator Staff Member

    I did not realise that there is a max number of characters that can be used in poll questions -- have edited it to increase.
  34. Thanks. Get voting y'all. This is research in action- be a part of it!
  35. Eric:

    I think that posting angle does matter, especially with firm rearfoot posts in firmer soled shoes. What I was trying to say in my last post is that in some patients, the difference between no post and a standard 4 degree rearfoot post may not matter, but that in other patients, adding or subtracting rearfoot post motion may matter in the therapeutic results from the orthoses. As far as I can see, this is all part of the art and science of foot orthosis therapy and until we can do some good controlled research on this subject, we are all just guessing as to how important posting angles are in producing optimum orthosis results. My educated guess is that posting angle is very important in some patients and not very important in other patients.
  36. I recall reading somewhere, if only I could remember where, that initially Root used to dispense devices without a rearfoot post and then bring the patient back at a later date (I think it was about 2 weeks-month?) and add the extrinsic rearfoot post. Are we saying then that since the difference between no post and a standard 4 degree rearfoot post may not matter in some patients (how do we spot those patients?), it may be a good approach to initially make the device without a rearfoot post and then add it later if required?

    My work to date with finite element modelling appears to show that the addition of an extrinsic rearfoot post does stiffen the medial longitudinal arch area of the orthoses shell. Changing the angle of this post does increase the stiffness in the arch further, but by relatively small amounts. So perhaps the solution is to add a zero degree post/ stabilizer initially, or just stiffen the medial longitudianl arch section of the shell which would have the same net result?

    If we take a 4 degree post with 4 degree motion, is this not analogous to rolling the ball up the hill (decelerating pronation) and then allowing it to roll down the other side (accelerating pronation)? Or is it the angle/ position of the "apex" of the "ridge" between the posting grind and the motion grind which is significant? Since this effectively forms the high ground, will it not draw the centre of pressure toward it in the same way that a track of pins might?

    I think this is fascinating. To your statement that: "we are all just guessing as to how important posting angles are in producing optimum orthosis results." I would add: we are therefore just guessing when we add the posting angle to the orthosis"
  37. Lawrence Bevan

    Lawrence Bevan Active Member

  38. efuller

    efuller MVP

    My protocol could be applied to a prefabricated device. You do have to think about getting paid for your time. How long does it take to modify a prefab and how long does the prefab last.
  39. Good point, Eric. I was talking to one of the non-podiatric clinicians at the San Diego PFOLA meeting and found out that they prefer to use an inexpensive prefab orthosis and then modify it over time instead of casting a patient for custom foot orthoses. They said that custom foot orthoses were "too expensive" and "not shown to work any better" than modified prefab devices. However, I asked them how much they charged for the prefab orthosis (about $75.00) plus the 3-4 office visits used to modify the orthoses and make sure they were working correctly (at about $65 per visit) and that needed to be replaced or refurbished every one to two years. I then informed them that their "inexpensive foot orthosis fee" was actually costing their patients more than my "expensive custom foot orthosis fee", since my custom foot orthoses often lasted between 5-15 years for my patients with minimal need for return visits or refurbishments. They seemed somewhat surprised by my cost analysis and that my "expensive custom foot orthoses" actually cost the patient less than their "inexpensive modified prefab foot orthoses" which they assumed were less expensive to their patients simply because they only included the cost of the orthosis itself, not the full and ongoing service and maintenance of the orthosis for the patient over the life of the individual. Unfortunately, this lack of understanding regarding the actual monetary cost and time cost to the patient for the two types of competing foot orthosis services is common place, even in those with advanced academic degrees and who teach such subjects to podiatrists and other foot-health clinicians.

    Therefore, before anyone believes that custom molded prescription foot orthoses are always "more expensive" than a prefab orthosis that is being continually modified and refurbished and replaced by the clinician on a quarterly or yearly basis, they should perform a reasonable cost analysis of the treatment over a 1 year, 5 year and 10 year period to see what the actual cost of the medical service is over that time for the patient. I believe, that, in the final analysis, custom foot orthoses are often more effective over a longer period of time, less expensive over a longer period of time, and require less of patient's and clinician's valuable time to keep the orthosis working properly over a 5-10 year period.

    For example, the polyproplyene foot orthoses I have now been wearing on a daily basis since 1989, and which are medically necessary for me to prevent the occurence of plantar fasciitis ane medial knee pain, are now about 18.5 years old. If I had paid $400.00 for these custom molded prescription foot orthoses and did not need to return to the podiatrist for refurbishments for 18.5 years, the cost per year for that ongoing medical treatment would be calculated to be $21.62 per year. Even if an office visit of $65 every 3rd year was needed to inspect and make sure that the orthoses were functioning properly (which normally doesn't happen in my patients), the cost per year for my medically necessary foot orthoses would only be $42.29 per year. I would like to see a clinician make modified prefab foot orthoses over a 18.5 year period that worked as constantly and effectively for a patient for less cost than that!!

    Therefore, we can't continue to allow the penny pinchers within the governmental agencies and health insurance authorities to make this argument for the cost savings of "modified prefab orthoses" without us first presenting a more realistic cost analysis of the effective medical worth of custom-molded prescrition foot orthoses for our patients. If we don't make this argument for our patients, then who else will?!
    Last edited: Jan 8, 2008
  40. Intersesting discussion, as always, however I seem to recall this topic being discussed previously.

    I guess what this thread and others before confirm, is the variable rate of successful clinical outcomes in both prefabricated and custom devices given the many permutations in design and fabrication and how individual foot types react to orthotic therapy. I can appreciate your reasoning regarding cost benefit, Kevin, but I would think that is some healthcare systems, such as the NHS in the UK, trying to convince a purchasing director that a custom device, which may not be any more clinically effective than a prefabricated one, would be an extremely difficult task on current evidential base.

    Best wishes


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