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STJ neutral and Forefoot deviation

Discussion in 'Biomechanics, Sports and Foot orthoses' started by RobinP, Aug 11, 2010.

  1. RobinP

    RobinP Well-Known Member

    Members do not see these Ads. Sign Up.
    This is one of those really basic questions that goes round in my own head that I struggle to answer.

    What relevance is the relationship between sub talar neutral position and forefoot position - eg. a forefoot supinatus?

    Given that the determination of sub talar joint(STJ) neutral can vary wildly between and within practitioners, the measurement has limited clinical application given its inaccuracy

    But even if it wasn't, how can we determine how much angular deformity of the foot can be attributed to the forefoot deviation and how much to STJ axis deviation and other factors.

    Let us imagine that I have a large, true "FF varus". How can I determine that there is a FF varus without looking at it relative to STJ neutral. Is it simply that the forefoot be parallel to the weight bearing surface when the sub talar joint is maximally pronated?

    I'm sorry if this is not very clearly described but I feel as if there is a disconnect between assessing STJ axis position, altering its spacial location and therefore its effect on the forefoot versus using STJ neutral to determine relative forefoot position.

    Will appreciate any guidance - perhaps I am confusing two completely seperate things?


  2. efuller

    efuller MVP

    I believe we have discussed this multiple other threads.

    In short forefoot to rearfoot is not measurable. There's over five degrees of error in the heel bisection. As you pointed out, neutral position of the STJ will vary across practitioners. The position of the forefoot will change with the amount of pressure applied when "locking" the MTJ. The position of an unloaded medial column will vary over time.

    At a "biomechanics" conference I asked several podiatrists to measure forefoot to rearfoot of the same individual. There was a 10 degree range.


  3. drsha

    drsha Banned


    Not that I disagree with your statements but they seem to provide "personal expert, anecdotal" Level 5 Evidence at best.

    Do you have any stronger evidence to back up this opinion about the STJ? Please provide.

    Dr Sha
  4. Graham

    Graham RIP

    don't know the exact ref but didn't Smith & Perinowski? demonstrate a similar error of measurement of the stj as Eric suggests?
  5. Also found this one

    Attached Files:

  6. Jeff Root

    Jeff Root Well-Known Member

    The fact that some people can't measure ff to rf reliably doesn't mean that it can't be done. I would like to offer Eric a public challenge. Spend some a day or two with David Francis, DPM who took over my father's practice and then come back tell us it can't be done. There exists a group of properly trained individuals who can measure ff to rf reliably. Being one of them, I know!

    Jeff Root
  7. A better question might be: why would you want to? ;)
  8. Jeff Root

    Jeff Root Well-Known Member

    What, want to learn?
  9. You know me Jeff, I always want to learn, you?:drinks
  10. Jeff Root

    Jeff Root Well-Known Member

    Eric adamantly stated it can't be done. I disagree. That's why.

    Kevin tells me he can take reliable measurements. Clinicians use the terms inverted forefoot, everted forefoot, ff varus, ff valgus, etc. All of these rely on heel bisection and ff to rf measurement. How else can you tell the relative position of the ff. I propose a new law. If one doesn’t believe that ff/rf measurements are reliable, then one shouldn’t be able to use the above terms! If only I were king! :D
  11. Tell me, what is the best "level of evidence" that could be achieved in a single study designed to test the reliability of a clinical measurement technique?

    Simple numerical answer required....
  12. Jeff, you don't need to be able to measure to qualify a position. There is a big difference between quantitative and qualitative assessment of forefoot to rearfoot relationship. Moreover, you still haven't told me why forefoot to rearfoot relationship is important. Lets say we measure two feet: one has a forefoot which is inverted 10 degrees relative to the rearfoot in subtalar neutral and one which has a forefoot that is everted 10 degrees to the rearfoot in subtalar neutral. For the sake of discussion, we know that I've measured these accurately, even though I've done it using one of those horrible forefoot to rearfoot measuring devices. In isolation, how do these measures change my prescription?
  13. Jeff Root

    Jeff Root Well-Known Member

    Not to mention, hundreds of thousands of custom foot orthoses are manufactured and need to somehow be oriented in the frontal plane during the manufacturing process (fact!). You can use a clinically derived, but imperfect technique to do this that is based on human anatomy or you can ignore it and just place the cast or scan of the foot randomly, somewhere in the frontal plane.

    After creating a proper heel bisection (see pics), how many practitioners own a forefoot measuring device which was specifically developed to measure ff to rf relationships? I have one but they are no longer produced, or are they?: http://www.hearonseminars.com/store_other.html. We don't even both to use the proper tools to do the job and then we claim lack of reliability. Very frustrating! You can't measure it reliably with a tractrograph like they try to teach it in the podiatry schools!

    Jeff Root

    Attached Files:

  14. As we both know, there are a number of ways to do this. If, for example you use a weightbearing cast you can take the flat section of the heel fat pad as a reference. The forefoot to rearfoot relationship in such casts is usually parallel. You can even use the medial and lateral curvatures on the posterior of the cast. You can bisect the heel in neutral and transfer this during the casting process, etc, etc,- none of these have too much to do with the ability to reliably measure forefoot to rearfoot alignment in-vivo. I do have a forefoot to rearfoot measuring device, it's a dog of an instrument unless you've got three hands or more, in my opinion. But, if I give you a forefoot to rearfoot measurement in isolation what does this tell you? It tells you whether the forefoot is inverted or everted on the rearfoot in subtalar neutral position, if we are 100% accurate. But what is the clinical significance of this?

    As I recall Jeff, forgive me if I'm wrong, your father was using the device in an attempt to determine the position of the midtarsal joints- right? The midtarsal joints being the talonavicular and calcaneocuboid joints.
  15. Jeff Root

    Jeff Root Well-Known Member


    A functional orthosis should have intrinsic or extrinsic forefoot to rearfoot correction in it. This requires using a non-weightbearing cast of the foot. Any semi-weightbearing or weightbearing cast of the foot reduces the contours of the foot due to compression of the plantar fat pad and due to compensatory motion of the osseous structure of the foot in response to the flat, weightbearing surface. A functional orthosis must be made from a non-weightbearing cast and the cast should be processed with a balance platform under the met heads to enable support of the cast (ie resulting orthosis) at a designated position within the frontal plane (heel vertical, inverted, or everted at a specific angle).

    The practitioner’s negative cast and his/her ff to rf measurements should be very close, otherwise a measurement error has occurred or a casting error has occurred. The laws of physics tell us that if we apply the same amount of force in the same direction to the forefoot while the STJ is in the neutral position, then the ff to rf angle will be the same whether we are casting or measuring the foot. The key is knowing how to position the foot during both activities to produce the same or a very similar result. Clearly, some clinicians can’t do this based on their results.

    Some practitioners rely on the ff to rf measurements taken from the foot and from their cast to be within acceptable limits (their acceptable limits, not necessarily mine). As you can see from my previous photo of the calcaneus, the posterior, superior calcaneal surface has a parabolic shape to it. It is possible to bisect a parabola. A Haglunds deformity can alter the parabolic shape of the calcaneus, but once the apex of the calcaneus is found via palpation, a midsagittal bisection can still be done between the outer margins posterior calcaneal surface by using simultaneous digital palpation. The lack of application of a standard calcaneal bisection technique contributes significantly to variability in biomechanical findings. I have seen gross heel bisection errors that make me question whether the practitioner ever had any instruction in anatomy!

    Part of the clinical significance of ff to rf measurements is reflected in the contour of the cast and orthosis. If you invert (ie supinate) the forefoot and create a fifteen degree inverted ff to rf angle in a foot that has a plantarflexed 1st ray and measure 15 degrees of forefoot valgus (ie 15 ff eversion), then you would have produced a 30 change in the ff to rf angle! An intrinsically corrected (balanced) 15 valgus orthosis should have a significant valgus build up at the anterior, lateral aspect of the device and along the lateral column, including support of the increased calcaneal inclination angle. This should appear much different than a 15 degree inverted, intrinsically corrected orthosis that has a varus build up medially and a low lateral column and lower calcaneal inclination angle. So from an orthotic design and manufacturing standpoint, there is huge clinical significance in ff to rf. It is highly important to many of us who practice Root type functional foot orthotic therapy.

    My 16 year old son has a significant plantarflexed 1st ray and depends on intrinsic forefoot valgus support to prevent reoccurrence of inversion ankle sprains in soccer and baseball. A semi-weightbearing cast would not allow me to create intrinsic forefoot valgus support and would not provide the same level of resistance to retrograde heel inversion. This is how I and others apply the use for forefoot to rearfoot measurements in our daily functional orthotic therapy.

    My father was using the forefoot measuring device (which he developed and had a company that my cousin worked for originally manufacturer at no financial benefit to himself, he just wanted the tool!) to measure the relationship between the plantar plane of the forefoot relative to the sagittal plane bisection of the calcaneus. This angular relationship is influenced by the midtarsal joint, the relative position of the stj, a number of other joins of the foot. He typically measured the ff to rf relationship with the mtj fully pronated and stj in the neutral position for standardization of measurement technique purposes. He later determined that this was also a good position in which to cast the foot when making functional orthoses. This was determined through trial and error.

  16. Graham

    Graham RIP


    Tell me. It is still 2010 isn't it?

    Feels like 1995 on JISCMAIL!
  17. Jeff Root

    Jeff Root Well-Known Member

    It's nice to be consistent!;)
  18. Jeff Root

    Jeff Root Well-Known Member

    I have attached an article that I wrote with Doug Richie, DPM that clearly demonstrates the influence of grf on the forefoot to rearfoot relationship and the plantar contour of the foot. And for Graham's information, the laws of physics haven't changed between 1995 and 2007, when the article was written.

    Attached Files:

  19. RobinP

    RobinP Well-Known Member

    I'm sorry that this question has turned into the opening of an old debate. I have read the threads on forefoot varus etc before and (probably due to lack of understanding of the more complex biomechanics) never really asnswered my question.

    I think what I am really asking is what is the relevance of STJ neutral given that as a measure in itself it doesn't really mean much and cannot readily be defined. Clearly, the practical application of manufacturing and providing a basis for measurement means that it will continue to be widely used.

    However, in my clinical notekeeping, I have begun to shy away from such terminology due to a lack of ability to be able to define it accurately.

    This is a better example of the disconnect I referred to. Clinically a measurement which has limited application but essential to the fabrication of the orthoses we prescribe.

    Could we fabricate(central fabrication unit) without reference to STJ neutral position, What would the terminology be?


  20. Jeff Root

    Jeff Root Well-Known Member

    The neural position is just one point in the total rom of the stj. Don't try to make more out of it than it is. Let me give you an analogy.

    What's more important, 12:00 noon or 1 p.m. or 12 midnight? Neither! I could use military time and say 1200 hour or 1300 hours 2400 hours. The a.m. and p.m. just divides the day in half, (before mid day and after mid day) much like supinated and pronated divides the relative position of the stj. The difference is we can measure time more accurately than we can stj motion.

    But let's assume that we didn't have a watch. We couldn't tell the exact time. But I bet you could still give me a relatively good estimate of the time of day by looking at the sun, especially relative to the position of the sun yesterday when you did have your watch. But if you never had a watch, and never looked at the position of the sun relative to the time on a clock, I bet you couldn't give me an accurate estimate of the time.

    Many of the beneficiaries of the concept of the neutral position fail to appreciate its value. But, if they had never been clinically trained to appreciate and use the relative position of the stj as a guide, would they be as effective clinically? Probably not.

    I bet you would have more difficulty telling me the time during the night, because you wouldn’t have the relative position of the sun above you to help you estimate the time. Could you tell me if the foot was in a supinated or a pronated position if you couldn’t move the stj and examine the rom? What if the joint was fused? Is it fused in a supinated, neutral or pronated position? Is the heel fused in an inverted, vertical, or everted position? Relative to what, the floor or the leg or??? If you were the surgeon who was asked to do the fusion, would it be important to know these reference positions? Yes. So if I said I will meet you a one o’clock, wouldn’t it be useful to know if I meant a.m. or p.m. STJ neutral gives us the sense of relativity. It’s not a perfect system, but it does have purpose.

    In manufacturing functional orthoses, the lab doesn’t need to know the neutral position of the foot provided the practitioner tells the lab exactly what position they want the heel placed in (i.e. specific number of degrees inverted or everted, or vertical). If the practitioner tells the lab to “post the cast to the neutral position”, the lab has absolutely no idea where that patient’s neutral position is. The lab can only guess where to position (correct) the cast. Vertical isn’t necessarily neutral. In fact, vertical is everted from neutral on average given the frequency of rearfoot varus as compared to rearfoot valgus.

    The bottom line is that we need accurate terminology to communicate. At Root Lab we deal with the specific frontal plane position of the heel bisection for cast correction and we encourage standardization of the heel bisection technique to reduce variability as much as humanly possible.

  21. drsha

    drsha Banned

    Eric may be unavailable but as a person who claims that others don't respond to queries and one that requires evidence of paradigm in order to attach or inspect remains silent as to the critical questions regarding STJ Neutral that I posed.

    What is even more critical than the thought that STJ Neutral is subjective, qualitative and relative (by recent admissions from Jeff et al) is the even more absurd leap that STJ Neutral casting should be (and is) utilized for producing custom foot orthotic shells which are then prescription customized case specific by biomechanists.

    My work, for the past 5-10 years has not used STJ Neutral casting as described by Root for generations EVER.

    I wonder if others can justify the use of STJ Neutral casting EVER and if not, what is the protocol clinically for the varying casting techniques being used.

    Can we interpractitioner poll for the types of casting used per 100 shells?

    Dr Sha
  22. Graham

    Graham RIP

    I guess! If you don't mind being consistently wrong:boxing:
  23. Jeff Root

    Jeff Root Well-Known Member

  24. Phil Wells

    Phil Wells Active Member


    As a fellow orthoses manufacturer I feel that we may see the same problems with cast quality etc.
    However I have to question your statement re orthoses must be made from a negative cast.
    They can and are made successfully using semi and fully weight bearing casts with the following rationale.
    The foot is placed into a foam box at its end ROM or pathology inducing position. The practitioner then takes a corrected or semi weightbearing impression and compares the two.
    The difference between the 2 gives significant evidence of 'potential' pathological forces that may be occurring.
    Can a single non-weight bearing cast do this?
    In addition the osseous and soft tissue structures are functioning nearer 'normal' for that individual.

    I think it time to move past the dogma of casting and allow practitioners to start having more control of the forces they want the orthoses to apply to the foot via ORF.


  25. drsha

    drsha Banned

    Would the second cast be STJ Neutral or otherwise?

    Dr Sha
  26. Jeff Root

    Jeff Root Well-Known Member


    I appreciate your constructive criticism. The term functional orthosis was coined by Dr. Root to describe an orthotic device that was created by him using a fairly specific casting and manufacturing protocol. As the term functional orthosis began to be used more broadly, practitioners, educators and researchers started using the terms “Root Functional” or “Root type functional orthosis” to differentiate it from other devices that were manufactured using significantly different protocols. A Root type, functional orthosis can only be made from a non-weightbearing cast or scan of the foot. I believe this casting technique is one of the key differentiating factors that distinguishes it from other devices. As you may recall, someone on this forum recently was attempting to suggest that a shoe could be considered a functional orthosis. This is one example of how the term is distorted by others.

    I was not passing judgment on the other devices nor was I attempting to imply that they don't have clinical merit. I was simply attempting to restrict my comments to the manufacturing protocol for a Root type functional orthosis and its designated casting technique, including the purpose of heel bisection and the significance of forefoot to rearfoot measurements.

    Thanks for giving me an opportunity to clarify myself.

  27. Jeff Root

    Jeff Root Well-Known Member

    In the article I uploaded earlier in this thread, I bisected the heel of the subject and I took three different casts: 1) neutral suspension, 2) semi-weightbearing, neutral calcaneal stance 3) full weightbearing, neutral calcaneal stance. The calcaneal bisection was drawn on the foot using an indelible pencil and was re-marked prior to each casting. The heel bisection line transferred to each negative cast, therefore there was no difference in the heel bisection for reference purposes.

    Using the common ( Root protocol) heel bisection in all three casting conditions, the patient who demonstrated a forefoot valgus on non-weightbearing exam and in the suspension cast, demonstrated an inverted forefoot to rearfoot relationship in both the semi and full weightbearing conditions. It is clear that both techniques resulted in supination (inversion) of the forefoot relative to the rearfoot when compared to the non-weightbearing technique when using a common heel bisection. This occurs when the subject with an everted forefoot pronates in stance and the forefoot remains parallel to the floor or is inverted by the casting foam block. There was significant loss of medial arch height and plantar heel contour (see pictures in article) as compared to suspension or non-weightbearing casting. Had the cast not been taken with the patient standing on a 2 inch foam pad, the foot would be dramatically flatter because the foam pushed up on the soft tissue to create some plantar contouring.

    One of the reasons for writing the article was to educate practitioners who take casts for functional AFO’s, such as the Richie Brace™. Many non-podiatrist practitioners (orthotists, etc) who cast for functional AFO’s used a semi or full weightbearing casting technique. The plantar surface of these casts is very flat and the foot plate is relatively flat and does not allow us to create a functional foot plate. Those who use a suspension technique get a true, functional or Root type functional foot plate in their functional AFO's. This results in far better support and control of conditions like adult acquired flatfoot.

    I don’t know if practitioners who don’t use Root type functional foot orthoses make functional AFO’s or how they treat these feet, especially patients with severe adult flatfoot or drop foot post CVA. A functional AFO can be made with a Tamarack hinge in order to provide dorsiflexion assistance. This is an extension of the functional or Root type functional orthosis protocol.

    I believe that suspension casting has some distinct advantages over these other techniques for treating most pathology. Certainly for some types of accommodative or less controlling devices, these other techniques have a purposes. Here is the link to the article again:

    Attached Files:

  28. Phil Wells

    Phil Wells Active Member

    Dr Sha

    That's the whole point. The cast alignment is based on the clinicians perspective of where they would like the orthoses to begin from i.e. facilitate the link between the cast and ORF.
    This means that foot typing, paradigms etc are part of this but only after the clinician has identified what's broken and how they would like the orthoses to apply a beneficial ORF.
    I believe this is the only way the profession can move forward and foot typing etc are negative influences on us.

  29. Phil Wells

    Phil Wells Active Member

    Fair points well made.


  30. Nice, Phil. It ultimately all comes down to orthotic reaction forces. So to keep in the context of this thread: I measure a 10 degree inversion of the forefoot to rearfoot with the subtalar joint in neutral, either from the cast or in-vivo in one patients foot, and a 10 degree eversion of the forefoot to rearfoot with the subtalar joint in neutral in another patients foot. In isolation what do these measures tell us that is of clinical use?

    Lets say both patients suffer with Achilles tendinopathy. How do these measurements in isolation alter our prescriptions?
  31. In this case they would not, due to the fact that your 1st call in treatment is most likely to be a heel lift to reduce the load on the stressed tissue ie the achilles tendon.
  32. Jeff Root

    Jeff Root Well-Known Member

    You're taking the purpose of the measurements out of context. Let me give you a realistic scenario.

    Let's say that the patient is a 60 y.o. female who on initial presentation is complaining of medial tibial pain, medial ankle pain, and medial arch pain on the left foot. On exam, we note a 10 inverted forefoot to rearfoot relationship on the left foot and a 5 degree everted forefoot to rearfoot relationship on the right foot. We can see, based on our anatomical understanding of the parabolic nature of the posterior, superior surface of the calcaneus and our resulting heel bisection that the left heel is significantly everted as compared to the right foot. We can see medial talonavicular prominence, decreased medial arch height, and relative abduction of the forefoot to the rearfoot on the left foot relative the “ideal standards” and relative to the more “normal” appearing, right foot.

    Based on these simple clinical observations and the patient's symptoms, we very quickly can begin to suspect unilateral adult acquired flatfoot. We can explain to Mrs. Smith what we see and suspect and Mrs. Smith will appreciate that we can explain the likely cause of her symptoms. We can use this preliminary diagnosis as we embark on further examination and treat, which might include foot orthoses or a functional AFO.

    So, I believe this information is useful for those who choose to use it in a manner that is consistent with their education and training. That said, perhaps others might take a different approach. This could include no examination and simple trial and error in an attempt to change the forces that are causing pain. I believe the best approach is to evaluate the structure and attempt to identify the source of the pathological forces and address them directly. Examining Mrs. Smith’s structure helps me to do just that.
  33. Jeff, I gave you a realistic scenario... one which I see very frequently... patients with forefoot to rearfoot relationships which are very different, yet presenting with the same pathology. Can you resist this argument, rather than changing the proposition?

    I asked previously and I may have missed your response, if so once again forgive me: wasn't your father trying to make inference to the position of the talonavicular joint (TNJ) and calcaneocuboid joints (CCJ) through his measurement of forefoot to rearfoot alignment?

    I'm just not sure how we can infer the position of the TNJ or CCJ from a measurement made around the metatarsal heads and the heel when there are a number of other joints between the anatomical structures being measured and these midfoot joints. Moreover, the measurement of forefoot to rearfoot alignment takes no consideration of the load/ deformation characteristics of the individual rays. So for example, we measure a forefoot that is inverted relative to the rearfoot by 10 degrees in subtalar joint neutral, is this a supinatus, or a forefoot varus? Should we approach these in the same way with our orthosis? I think it is an over-simplified reductionist approach, which takes little consideration of the presenting pathology and assumes that function during a locomotor task is entirely dictated by the position of the forefoot and/ or position of the rearfoot and their inter-relationship at a somewhat arbitrary point within the forward walking gait cycle, which is then being assessed non-weightbearing and extrapolated to weight-bearing function. Personally, I find it too restrictive and unrealistic.

    As I said, two patients, same pathology, vastly different forefoot to rearfoot alignment. Do we "bring the ground up to foot and negate the need for compensation"... Or use our knowledge of foot orthosis effects and design the orthosis to modify ground reaction forces in such a way which should reduce stress upon the target tissue ...

    I think the achilles tendinopathy is a good exampe here. Is "unilateral acquired flat-foot", really the pathology in Mrs Smith, or is it just a description of her foot type? How many people do we see with pes pancakus and no obvious pathology? Indeed, how many people do we see with the same "foot type" yet vastly different pathologies?
  34. Graham

    Graham RIP

    The foot orthoses is just a frame, much like a pair of glasses. It is up to the clinician to ensure the frame is not "bent" before they apply the prescription!
  35. efuller

    efuller MVP

    Dennis, I apologize for not logging on to the arena since 5:18am in the morning yesterday. Don't you think that is a little fast to be critical of me for not responding?

    My evidence is unpublished studies that I've done. One study done at the department of biomechanics at CCPM we all tried to bisect the same person's heel. Tape was placed on the heel, the bisection was then penned onto the tape and then removed when the next member of the department tried to bisect the heel. One examiner would place the foot in the maximally pronated position and use a tractograph to measure the maximally everted position and compare the measurements across practioners. There was a 5 degree range amoungst the memebers of the department. In my earlier critique of forefoot to rearfoot measurement, I did not even mention instrument error.

    A second unpublished study was done at one the Weed memorial seminars. I asked several attendees (all podiatrists interested in biomechanics) to measaure the forefoot to rearfoot relationship of one individual. If I recall correctly they were to use a given heel bisection. There was a 10 degree range across those who submitted measaurements.

    Dennis, The best defense is not always a good offense. Your complaints about me not answering questions still does not absolve you of answering questions that I posted in the other thread. Can you tell me what a vault is? Can you tell me which bones make up a vault?

  36. efuller

    efuller MVP

    Your heel bisection is 2-3 degrees everted from where it should be. :D

    This is my point. Not every practitioner will bisect the heel the same way. It doesn't matter if you were to use some electronic device that could find the heel bisection line in three dimensional space and compare it to a line placed onthe metatarsal heads. The difficulty is in defining the correct lines so that the measurement is repeatable across time and across examiners.

  37. efuller

    efuller MVP

    What I use is how much intrinsic forefoot post I want in the finished device. You can give the lab a number that does not refer to neutral or to heel bisection. You put the cast on a table with the first and fifth met heads touching the table. Draw some arbitrary line on the heel and then if you wanted a 4 degree intrinsic forefoot valgus post, your cast correction will evert the line 4 degrees from its original position.

    The heel cup of the orthosis can be made symmetrical in the frontal plane. If you make the device with a medial heel skive, the medial side of the heel cup will sit higher than the lateral side as viewed in the frontal plane. Again, you can describe the shape of the orthotic that you want without referring to forefoot to rearfoot or to the heel bisection.


  38. Jeff Root

    Jeff Root Well-Known Member

    Do you ever mark the stj on the plantar surface of the foot? I have to assume that you would not endorse this clinical technique since there can be several degrees of variability inter and intra practitioner. Hence, drawing the stj axis on the plantar surface of the foot is not repeatable and should be abandoned by al clinicians. I also draw mtpj frontal plane bisections on plaster casts of the foot to determine orthotic length. Absolute science, no! Clinically applicable, yes. Variability between clinicians, yes. So what is the point? Clinical practice is based on need and requires techniques that are not absolute. That’s nothing new, and not going to end any time soon.

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