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Forefoot Varus Predicts Subtalar Hyperpronation

Discussion in 'Biomechanics, Sports and Foot orthoses' started by NewsBot, Dec 17, 2014.

  1. drhunt1

    drhunt1 Well-Known Member

    Griff-thanks for the response.

    1. One of the problems I see inherent with Podiatric research is the length of time some of these pathologies take to "surface" vs. the length of time many of us practice. For instance, while it may take 50 years for a bunion to form, how many practitioners are in practice for that length of time, let alone seeing that patient over their entire course of development into adulthood? It's not the bunion that is inherited, it's the foot type that leads to a bunion that is. By overuse syndrome, I take it that you mean a soft tissue injury in response to a structural deformity? Achilles tendonitis from an ankle equinus deformity appears to have little to do with calcaneal position...neither does Anterior Tibialis tendonitis from a runner running up and down hills. But Posterior Tibialis tendonitis most certainly can be successfully treated by repositioning the calcaneus and midfoot, just as Peroneal tendonitis can. Not sure what you mean by overuse syndrome...in my opinion, it is a catch-all term for someone not quite sure where to place a certain painful condition much like Kirby did with growing pains in children.

    2. And as I have previously stated, while accuracy in drawing the heel bisection is important, I use it as a reference line. In the above pics I posted, I don't think the line is quite accurate as a true bisection...but taken as a reference line, comparing RCSP, (first pic), to the NCSP, (second pic) to the orthotic corrected, (third pic) gives the practitioner visual evidence that at least "some" of the STJ eversion has been corrected. Was it enough? Notice I didn't extend the forefoot varus correction on her orthotic to the end of the toes, like I have previously described. Since the time those pics were taken, I have. However, she was interviewed prior to that correction and reported resolution of most of her complaints before I corrected the forefoot. Here's a lateral view of her foot at static stance. Notice the forefoot varus deformity? Notice the "see through sign" of the STJ?

    3. Again, refer to my first point. Perhaps we, as a profession, need to focus on long term studies instead of viewing complex problems via "snap-shots" of that problem. I wrote at the beginning of this thread that Podiatry doesn't even have serial plain film radiographs of any one individual patient as they grow from childhood through adulthood. A consequence of the length of time some of these problems take to form vs. the length of time we practice our craft, combined with geographical relocation of these patients, I believe, contributes to the paucity of long term studies of long term problems. Whether, or not, current studies indicate that orthotics exert a consistent kinematic effect on our patients, disregards the individual anecdotal results of successful treatment, (resolution of their painful condition, thus allowing them to continue to function more normally), that when lumped together with other successful treatments of other patients' complaints begins to form a pattern.
     
  2. Griff

    Griff Moderator

    Hi Jeff

    I wasn't referring directly to the pictures posted per se; more a narrative that in general we should be aware that these sorts of markings (whether it be a pen line or a surface marker) may not truly reflect skeletal motion. In the picture above I'm sure its reasonable to assume there has been some angular change of the calcaneus in the frontal plane. Do we think this static observation will tell us anything about (i.e. predict) how the orthoses may 'work' dynamically though?

    IG
     
  3. Griff

    Griff Moderator

    Hi again drhunt1

    1. I'm not sure your comment about time lines is valid; 50 years for a bunion to develop? I've been in practice for 12 years and have probably seen bunions every single day of my professional life, and usually on patients in their 20s or 30s. Apologies for my terminology used - I refer to injuries as 'overuse' as habit purely based on the demographic of patients I personally see. We can replace the term with 'pathology' if you like. I'd still stand by the modified comment: Calcaneal position has not been shown to be predictive of pathology. Which begs the question (for me at least)... Why such focus on it?

    2. This ties in with my previous post to Jeff - are you of the belief that the "correction" (terrible term) that you see statically will somehow carry over into dynamic function?

    3. The interesting thing here is that we do not disagree - orthoses do work (alleviate pain) when used appropriately (and ironically often when probably used inappropriately). However, you appear to be viewing this through kinematic tinted spectacles. The research does not disregard clinical success as you suggest. There are other proposed mechanisms of action for foot orthoses and current understanding does not appear to point to their kinematic effects as the 'game changer'.
     
  4. Rob Kidd

    Rob Kidd Well-Known Member

    I watched bunions develop in my mother in 3 weeks - after a head on car crash. True she had had unstable feet all her life - and a single traumatic incident dipped her over, so to speak.
     
  5. I had a 25 year old man come into my office last year saying he thought he developed a bunion deformity from a rock climbing accident 3 months before I first saw him. He said the toe of his boot got caught in some rocks and he fell over, "spraining his big toe". Radiographs showed no osseous abnormality other then an increase in hallux abductus angle. Clinically, there was a remarkable asymmetrical bunion deformity. From the time I first saw him at the initial office visit, to the time I repaired the bunion surgically, about 8 weeks had elapsed and I was very impressed at how much worse the bunion and HAV deformity had gotten in that 8 week time period.

    During surgery, the medial collateral ligament of the 1st metatarsophalangeal joint was noted to have about 10 mm rounded hole (i.e. ligament tear) in it that I was able to surgically repair and, along with a Reverdin-Laird osteotomy, was able to get the hallux straight again. Remember, this was in a young man that had no bunion deformity on the opposite foot.

    It just goes to show you how lack of tension load-bearing structures on one side of a joint axis means loss of a significant magnitude of counterbalancing moments across that joint axis which, in turn, may mean fairly rapid progression of a foot deformity. In other words, not all bunions take years to form.
     
  6. drhunt1

    drhunt1 Well-Known Member

    Tough crowd in this place.

    1. I wrote that a bunion "MAY" take 50 years to develop, but it was to make a point...and that point is that "SOMETIMES" it takes years for certain pathologies of the foot to develop, "SOMETIMES" longer than the Podiatrist is in practice or seeing that patient. I've seen and done bunion surgery for patients as young as 11 y.o. Thank goodness that's not the norm. But we don't see bunions on newborns or really young kids, because the bunion is not inherited but the foot type that leads to bunions is. That was the point. Why focus on calcaneal position? You will have to wait until my article/pilot study on Growing Pains in children and RLS patients in adults is released before I delve much further into that...don't want to "spill the beans" before they're done. But in the serial pics I posted above: RCSP vs. NCSP vs. Orthotic corrected...what that 15 y.o. girl really needs is a medializing Modified Dwyer osteotomy to re-align the rear foot with the lower leg, then a cuboid osteotomy to dorsiflex mets 4 and 5, with a Modified Hoke procedure to plantarflex mets 1-3, both to re-align the forefoot to the rear foot. Incorporated in the Hoke is a partial Anterior tibialis tendoplasty with the posterior tibialis tendon, both placed UNDER a periosteal flap of the navicular bone and also tightening up the spring ligament creating a new medial buttress. Sounds complicated? It is. I've never performed all three procedures at once but assisted a very well trained Podiatrist on several that each took ~2.25 hours...relieving the tourniquet after 1.3 hours. But it all made sense and I've followed up with several of those patients for years afterward. Sometimes, osseous intervention to re-align the rear foot to the lower leg, and the forefoot to the rear foot is required. And it works.

    2. Yes...I believe that orthotics do function dynamically...perhaps not as well as we would like them to, but I believe they can.

    3. I never suggested that orthotics are a "game changer", they've been used in some fashion longer than I've been alive. My discovery of the cause of GP and it's ties to RLS may be a game changer, (time will tell), if for no other reason than it was a Podiatrist that discovered it...and that is good for our profession as a whole, no matter which side of the pond you reside.
     
  7. Jeff Root

    Jeff Root Well-Known Member

    Ian,

    There are those on the podiatry arena that have stated that orthoses don't change the position of the osseous members or segments of the foot. However, studies such as one by Tom McPoil do demonstrate that a change in tibial rotation from orthoses does occur and that it corresponds with a change in stj rom due to the coupling between the tibia and calcaneus at the stj. So yes, I do believe that orthoses can and often do produce a change in the position of the osseous members of the foot. However, some of those changes may be so small that we are unable to detect them with the naked eye. In other cases, orthoses may reduce pathological forces without actually changing the osseous relationship of the foot. And in other cases, graphic changes can be seen.

    In the picture posted by Matt, I would definitely expect to see an observable change in the frontal plane position of the calcaneus during gait. The trained eye can appreciate changes in gait resulting from orthoses. As a result, I'm not sure why this subject continues to be the subject of so much debate.

    Jeff
     
  8. efuller

    efuller MVP

    Yes, I am a proponent of the tissue stress theory. Yes, I am going to try and punch holes in what you believe. Do you feel that your logic can stand up to critical scrutiny? If you do, you should have no problem defending what you believe. You could also leave out the insults. I will try do so as well.


    Matt, you really missed my point. I would agree that videos of the motions of the bones of the foot can help students understand what goes on. If we were to choose a video for students to learn from we could choose your artists conception video or we could choose Don Green's fluroscopy video of three different feet. (The x-ray exposure that occurred in that video happened over 25 years ago and has no bearing on whether or not the video would provide a good learning experience.)

    Matt, are you aware of the chapter on computerized gait analysis that I wrote for Valmassey's textboot? I did discuss motion analysis in that chapter. I don't remember if I discussed measurement error related to skin marker movement relative to bones in that chapter. I do recall reading papers on it, when writing that chapter.


    So, how did comparing RCSP to NCSP change your treatment plan? If it did change your treatment plan, what rationale did you use for changing the plan? Matt, this is critical thinking.
    What is cast out the forefoot deformity?

    Eric
     
  9. I agree, the data just doesn't support that foot orthoses never change kinematics; but for every study which does show a significant change, we can pick another which didn't. The key issue is prediction of kinematic change in relation to foot orthosis design. In the Mcpoil study you cited, each subject was issued two types of foot orthoses: a pair of rigid, plastic orthoses with posting in either the forefoot or the rearfoot, and a pair of soft, accommodative, premolded orthoses with no posting. Both types of orthoses reduced rate and magnitude of internal tibia rotation, but there was no difference between the soft and rigid, posted foot orthoses. Then we've got data like that from Ngg et al. 1998, where you've got some subjects showing increased rearfoot eversion in association with decreased internal tibial rotation and vice versa and the Williams et al. 2003 study in which both a neutral postion (Root) device and Blake inverted devices both increased the peak rearfoot eversion when compared to no device at all. Although this increase was no statisitically significant, it is obvious that the foot orthoses did not exert their therapeutic effect by changing rearfoot kinematics in this study.

    Obviously we have to be mindful of methodological weaknesses particularly where angular data is being derived from 2D systems.
     
  10. rdp1210

    rdp1210 Active Member

     
  11. Griff

    Griff Moderator

     
  12. rdp1210

    rdp1210 Active Member


    I'm extremely disappointed with anyone who would put anyone else on the ignore list. It is the sign of a super-ego that has no place in the realm of scientific inquiry! I would encourage everyone who has put anyone on the ignore list, to please remove such. You don't have to respond to everyone all the time if you don't like what they have to say.

    Thank you,
    Daryl
     
  13. rdp1210

    rdp1210 Active Member

     
  14. rdp1210

    rdp1210 Active Member


    Actually over the last hour, as I have been treating patients, I have reflected on the postings to ignore a certain individual, and I'm sorry, but it stirs feelings of anger in me. If you want to ignore someone's comments, or not reply to them, that is your perogative. But the concept of such a public posting, stating that nothing the person says is of any worth is not just total egotism, but is also a form of encouragement to others to do the same, and is very much a form of cyber bullying. It is an attempt at thought and expression control. Sorry, but I have to call it what it is. All I can say is shame on those who would make such postings.

    Daryl
     
  15. drhunt1

    drhunt1 Well-Known Member

    Eric-if you discontinue to be condescending towards me, then I'll stop with the insults. Yes, I saw your chapter in Valmassy's book. Yes, it was written before animation became a really big deal. Back in the late '90's, good animators, (like those that were hired at Pixar), were being paid $300/hour and up. Now, a pretty decent animator with rigging experience goes for $30/hour. Big difference. While Dr. Green's fluoroscopy studies can provide students with insight in how the bones of the feet function and ROM involved, it is still limited by those three individuals foot types. What types of feet are they? In todays climate, fluoroscopy makes little sense because of the massive amounts of radiation imparted upon the subject...and that was MY point. A good animator can align the bones of the feet with the actual video of the patient walking, using skin markers to line points on the animation to real time video of the patient. That was the last video sequence that I didn't show, for the reasons I discussed. But in that video's audio narration, I discuss the value of such endeavors...and I stand by my interpretation.

    "Casting out" a deformity means that the patients' ROM allows the practitioner to hold the first met in a plantarflexory position while obtaining the negative cast, thus reducing the forefoot varus deformity. If little ROM is available, and it appears that the deformity is truly a structural one, then this cannot be accomplished.

    By placing the STJ in neutral, (like in the examples shown above), I can then decide how much rear foot correction I need and how much forefoot correction should allow the hallux to purchase the "ground". For the time being, I have dispensed with intrinsic corrections and have focused on extrinsic corrections, but bringing that correction out to the end of the top cover...to the end of the toes. I have received a lot of good feedback from my patients after doing this.

    Here's a really radical correction...about 15 degrees. I had to back off that correction some, but you get the idea. Interestingly enough, it was our local Prosthetics and Orthotist that I evaluated and interviewed that showed me his mock-up of an SMO....REALLY radical but I liked it...LOTS of possibilities. Perhaps I'll show pictures of his devices down the road. Suffice it to write that he has constructed a device that has ~15 degrees of forefoot correction as well for himself, measurements I gave him for his skewfoot deformity...and it has changed his life. His was a great interview...the cherry on top of my interviews. He had growing pains as a child, a recurrence of those pains in adulthood, (RLS), and has been plagued with lower extremity problems for years. Anecdotal? Perhaps...but just one piece in a broadening pattern.
     
  16. Are they?
     
  17. Jeff Root

    Jeff Root Well-Known Member


    Forefoot varus and forefoot valgus are structural deformities ( I prefer they be called structural conditions) that were defined by Merton Root. Here is a definition that came up as the number two link on a Google search:

    http://medical-dictionary.thefreedictionary.com/forefoot varus

    The terms forefoot varus and forefoot valgus should not be confused with an inverted (varus) or everted (valgus) position of the forefoot. For example, if you have a forefoot valgus and you invert the forefoot relative to the rearfoot, the forefoot will assume a varus or inverted position. This is not by definition a forfoot varus condition (deformity) since it is a positional relationship, not a structural condition. If so, we could say that virtually everybody has both a forefoot varus and a forefoot valgus condition (deformity). But since forefoot varus and valgus were defined as conditions that can only be assessed and determined when the stj is in the neutral position and only when mtj is fully pronated, then it is impossible to have both a forefoot varus and forefoot valgus.

    Root wrote that we need terms to describe structure, position and motion. Just as we use the standard anatomical position of the body with palms facing anteriorly and arms extended to describe relationships, forefoot varus and valgus must be determine with the foot placed in a standard position for evaluation and comparison.

    If I lean significantly to my left side, my left leg is inverted and my right leg is everted to the ground. Does that mean that I have a tibial varum on my left side and a tibial valgum on my right side? No. Because we recognize those as positional changes and not structural conditions that meet the accepted definition and use of the terms tibial varum and valgum. However, you could say that my left leg is in a varus position and my right leg is in a valgus position. The terms forefoot varus and valgus are no different.

    Although the terms forefoot varus and valgus were used prior to Root's refined definition, it was not always clear if one was using these terms to describe structure or position. Although there are those who may not want to accept these generally accepted definitions, they are generally accepted in the orthopedics community yet they are still sometimes used incorrectly.

    Jeff
     
  18. They may have been redefined by him, but forefoot varus and valgus deformities were conditions that were well known to the medical community and defined within the literature prior to your father's definitions of them, Jeff. For example here: http://www.ncbi.nlm.nih.gov/pmc/arti...01070-0007.pdf and here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2184416/pdf/procrsmed00526-0035.pdf They were being measured using instruments such as in the attached file. That your father may have redefined the defintions of them to meet his own needs, does not mean that "By definition, forefoot varus and forefoot valgus are assessed with the stj in the neutral position and the mtj fully pronated", only that by your father's definition they are assessed in this position, there is a difference!

    We could argue that no-one actually is capable of measuring these by your fathers definition since with the "MTJ maximally pronated" is not a clinically plausable statement.
     

    Attached Files:

  19. rdp1210

    rdp1210 Active Member


    Simon I'm glad to see you post George Perkins paper. I have always liked the paper and have referenced it many times in my writings and lectures. It is true that the words forefoot varus were being used before Root and that surgical correction was advocated for such. I tried to link to your first link and found only a "page-not-found" result. What I don't see in Perkins paper is any true quatitative method for measurement. He only advocates what in todays terminology would be called a relaxed calcaneal stance position. Also in Perkins paper does not detail what position the midfoot joints should be in when evaluating. Again, Root never invented the term 'forefoot varus'. However his "Root Postulate" did identify how to determine if it should be diagnosed. So we see Root trying to improve on what had gone in the past, trying to get everyone talking the same language and taking the same measurements. And as Jeff pointed out, he died, with only a work-in-progress. As I've maintained, there is almost nothing that Root taught that can't be found prior in the literature, except one has to dig to find it. The only unique thing I find in Root is his Postulate, until others can point to prior statements.

    BTW - think you can get us a set of those Thomas wrenches?

    Thanks
    Daryl
     
  20. I'll look on e-bay for the Thomas wrenches. Not sure what happened with that link, try this: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1927557/pdf/canmedaj01070-0007.pdf Root, showed a way in which it could be diagnosed, and probably did try to improve on the past. If the link works, you should see others had already provided a way in which it could be diagnosed and themselves had probably tried to improve on the past. As the supronometer patent reveals, others were already attempting to quantify this and to "balance" the forefoot posting to the measured angles. As history has shown, relaxed calcaneal stance may well be a more reliable position to take such measurements from, since the ground seems to be a better reference plane in terms of measurement repeatability than subtalar joint neutral. I pointed to a publication of the "root postulate" prior to 1977 in the root postulate thread, as I said in that thread, regardless of this publication from the mid 70's, Elftman, Inman and others had already described the relationship between forefoot and rearfoot position and the motion available at the midtarsal joints. As I've recently pointed out in this thread: "with the MTJ maximally pronated" is not a clinically plausable statement, given our understanding of midtarsal joint biomechanics in 2015.

    As I pointed out: God rest his soul. But the reallity is this: when did Root last publish a paper in a peer-reviewed journal? It's now 2015... Are you saying no-one has advanced our understanding of podiatric biomechanics since the mid 70's?
     
  21. Jeff Root

    Jeff Root Well-Known Member

    Simon,

    Good article. Thanks for posting the link! Although he talks about forefoot varus, the question is what is forefoot varus and how did he define it and expect others to determine if it existed in their patients? The definition was too vague. This is the problem Root recognized and why he chose to provide a more concise clinical definition. Root also mentioned that it did not require much force (only ounces according to him) to fully pronate the mtj in the relaxed foot. Clinicians who apply too much force can inadvertently pronate the stj because their pressure on the lateral forefoot is lateral to the stj axis, resulting in change in the ff to rf angle. That is why he stressed using the neutral position at the stj and doresiflexing, abducting and everting the forefoot to resistance using ounces of force.

    Jeff
     
  22. efuller

    efuller MVP

    Jeff, thanks for providing a definition of joint stability. The above is very helpful in analyzing the thought processes that went into the "Root paradigm." I'm sure I read the above before I started practicing the tissue stress approach. It definitely would lead one to think about stress on tissues.

    Now, this is a very broad generalization. It does fit logically with the first part above, but one should analyze each individual anatomical structure with regards to how body weight and ground reaction force will create stress on those structures. For example, in some feet, STJ pronation will tend to increase load on the medial forefoot and decrease load on the lateral forefoot. So, STJ pronation may increase stress on some structures and decrease stress on other structures.


    Now, this is a conclusion reached from a very broad generalization. The generalization is mainly based on alignment and having the forces appied to either end of a series of bones in which compression is formed. This alignment paradigm does not work so well for the first ray from the period of time between forefoot loading and toe off. How, does STJ position affect the alignment of the bones of the first ray in response to ground reaction force and body weight. McConail and later Sarafian propose the twisted plate theory where pronation of the STJ and dorsiflexion of the first ray (supination of the long axis) will increase tension in the plantar fascia making the first ray more rigid because of the windlass effect of the plantar fascia. The plantar fascia tension will tend to increase compressive forces and reduce moments that need to be resisted by the plantar ligaments of the first ray. So, the system that is the foot is complex and should not be simplified to supination of the STJ makes all joints of the foot more rigid.



    Ok good rephrasing of the question.


    To add to your question above. Why would we expect that casting the foot in neutral position, in some instances, will lead to a reduction in forces in some anatomical structures. If we had determined that an anatomical structure that creates a supination moment to resist a pronation moment from the ground is injured then we would want an orthotic to create a supination moment about the STJ to reduce stress in that structure. I am sure there is more than one answer to this.

    We should also explore the mechanical effects of "pronating" the MTJ in casting. How does this relieve symptoms and reduce stress in anatomical structures.

    Well said. There are observations and there are explanations of observations. I've observed that orthotics work. There may be more than one recipe that will lead to a similar orthotic and a similar outcome. If we want students of the future to believe our recipe is a good one, it should make sense and be supported by the literature.

    Eric
     
  23. We can agree that he redefined it, as opposed to defining it. As such we must also agree that there are multiple defintions of forefoot varus and forefoot valgus within the literature. Viz. the statement that "by definition, forefoot varus and forefoot valgus are assessed with the stj in the neutral position and the mtj fully pronated." is only applicable to your father's defintion- agreed?

    Jeff, the instaneous axis of rotation about the midtarsal joint complex is created by the force that is applied to it... But, let's go back a step before we go on, exactly how did your dad advocate "maximally pronating the midtarsal joint"?
     
  24. efuller

    efuller MVP

    Daryl, I'm open minded about heel bisections. The stick figures of the tibia and heel bisection are useful to teach students about the valuable concept of a partially compensated varus. However, I've been looking for better ways to get the information that we think we can get from heel bisections. What do you think of the maximum eversion height test?

    I'm also open minded about the center of mass and the moment of inertia of the calcaneus being important for what we do. If you have a rationale of how the heel bisection can represent either the center of mass or the moment of inertia of the calcaneus then I am willing to listen. In what formulas for motion will the moment of inertia of the calcaneus be a significant quantity?

    Eric
     
  25. Jeff Root

    Jeff Root Well-Known Member

    Simon, I agree. However, most if not all the podiatrists I deal with and hear at lectures are implying Root's definition of it. Perhaps we will some day find better terminology to differentiate this such as STJ neutral ff varus.

    That depends on when he was doing it. During neutral position, supine casting he placed the palmer surface of his thumb in the sulcus under the 5th, 4th 3rd digits and rotated his casting hand to bring the proximal phalanges into there stance position (either rectus or dorsiflexed). He then abducted, everted and dorsiflexed the forefoot on the rearfoot until the mtj rom was exhausted in each plane. Under certain conditions he would grasp the rearfoot with the fingers of his opposite hand on the medial and lateral aspect of the calcaneus above the plantar fat pad to prevent stj motion (which usually occurs in the direction of pronation since the force at the mtj is in the direction of pronation).

    During clinical examination, he would pronate the forefoot with the patient prone and/or supine by placing palmer surface of his thumb on plantar surface of the 4th and 5th met heads and then grasp the met heads between his thumb and index finger. He would then abducted, everted and dorsiflexed the forefoot on the rearfoot. If the subject exhibited additional transverse plane motion at the mtj or if the stj readily began to pronate at the mtj, he would hold the calcaneus so he could fully abduct, dorsiflex and evert the forefoot on the rearfoot without allowing the stj to pronate. When he used a forefoot measuring device, he had the patient prone and used a technique similar to the prone clinical examination technique.

    If you simultaneously abduct, dorsiflex and evert the forefoot on the rearfoot at the mtj, in the vast majority of cases, there is a very distinctive feeling of resistance or end range of motion. Unless you pronate the stj to allow additional mtj pronation, you are at or extremely close to functional end rom of the mtj. Yes, if you apply additional force that is resisted only by the ligaments and the connective tissue, you may get some small additional rom. Is this subluxation? The point is, when we cast the foot we have captured the shape of the foot that occurs when the mtj is essentially fully pronated. Any additional minor changes in shape of the foot that may occur with the use of additional force are virtually insignificant. In fact, some advocate plantarflexing the forefoot on the rearfoot (supinating the MTJ) to promote re-supination of the foot during gait. In my experience, this results in less comfortable orthoses.

    Jeff
     
  26. I find that very funny, Daryl, for you to mention "dogmatic religion" in this thread because, in my experience, Mert Root was one of the most dogmatic individuals I ever met, ever hear lecture and ever hear talk. From my own personal experiences with Mert Root, he talked condescendingly to anyone who challenged his beliefs and did so more than anyone else I have met during my entire professional life.

    If confronted with a question that didn't match his view of reality, Mert Root raised his voice, started nearly yelling, and started talking down to the person who dared question his authority in podiatric biomechanics. I experienced this first hand a few times from Mert Root. In addition, many of my professors who were taught by Mert Root also experienced the "wrath of Root", which confirmed my observations that Mert Root was one of the most dogmatic individuals that ever taught at the California College of Podatric Medicine (CCPM).

    When I was a podiatry student and Biomechanics Fellow at CCPM, John Weed and Ron Valmassy never acted like Mert Root, from my experience. Drs. Weed and Valmassy would always be more than willing to listen to my question, come up with an answer that wasn't condescending that was meant to provide their viewpoint on things, and would then offer me encouragement to continue to think independently. Mert Root, on the other hand, had a reputation for talking down to anyone who questioned his authority in podiatric biomechanics, didn't seem to want any new viewpoints offered to him and seemed to have established a reputation for acting this way to many who challenged his viewpoint among the faculty at CCPM.

    Now, maybe, because Mert Root was so dogmatic and forceful, this allowed him to spread his subtalar joint (STJ) neutral gospel farther than he would have if he had been more accommodating and willing to listen to alternative biomechanical viewpoints. Because Mert Root was so dogmatic and forceful, it did allow him to gather a group of disciples who wouldn't dare question what he said(I call them disciples since very few of them had the courage to question Mert Root and his beliefs in the many Root seminar meetings I attended).

    Because Mert Root was so dogmatic and forceful it allowed him and his disciples to better "spread the gospel" of subtalar joint (STJ) neutral being ideal, and teach the ideas that there were easily measurable "forefoot deformities" and "rearfoot deformities" in the human foot and that "balancing the negative cast to heel vertical" was best for most foot orthoses, and "heel vertical was normal (ideal)" and "tibia verticality was normal (ideal)". In other words, maybe if Mert Root had been more accommodating and willing to listen to alternative viewpoints and encourage independent thought, his ideas wouldn't have caught on so much and maybe he wouldn't have as many disciples who wanted to spread the "gospel of Root".

    At CCPM, the Root Subtalar Joint Neutral Theory that was taught to us was taught as dogma, not as theory. At CCPM, the Root STJ Neutral Theory was taught like there were no other ways of evaluating the foot. At CCPM, it was commonly believed by many that if Mert Root or one of his disciples didn't say it or agree with it, it couldn't be true. In other words, podiatric biomechanics was taught while I was a student at CCPM more like a religion, than as a ever-changing science, since no one dared question it's validity. And, from my experience, very, very few individuals had the guts to openly challenge Mert Root and his ideas (as I often did). Why? Probably because they were afraid they would be belittled by Mert Root for their ideas. Is that a way to move a profession forward? Certainly not. But that is what I saw happening at many of the Root seminar meeting and why I felt compelled to speak up against Mert Root and some of his ideas in order to show others that, indeed, all Mert Root said and taught was not the gospel truth.

    Now, what has resulted then from Mert Root's dogmatic approach to podiatric biomechanics that is now unraveling due to a lack of scientific research to support his ideas that he so stubbornly refused to let go of while he was alive and his disciples still refuse to let go of even today? It has resulted in a core group of Root disciples who believed Mert Root's ideas were the only ideas that made sense, that stopped reading the current literature over the past four decades that showed that Root's ideas were false in many cases, and insist that any new ideas that catch on are magically now ideas that should somehow be credited back to Mert Root.

    Now, does that mean I am a" Root basher". No, because I respected Mert Root greatly for all he accomplished for our profession. However, unlike some people on this forum, I am not going to let my respect for Mert Root cloud my vision to research and opinions outside the podiatry profession which offer much better and much more scientifically valid methods of evaluating and treating the myriad of mechanically-based pathologies of the foot and lower extremity that all podiatrists should be treating. Unlike some people on this forum, I am not going to continually go back forty or more years and continually bring up what Mert Root did, continually bring up what Mert Root said, continually imagine what Mert Root was thinking, continually speculate what Mert Root was going to do in the future, and continually talk about his and his relative's relationship with Mert Root. Unlike some people on this forum, I am going to keep my eyes and ears open, read the available literature inside and outside the podiatric literature and synthesize all of this information for the betterment of my patients and for the betterment of the worldwide podiatric profession by writing, lecturing and thinking long, long hours as to what speaks the truth to me, not that which seems to confirm what Mert Root said or wrote in the past.

    It is better that we, as Simon Spooner said in the other thread on "The Root Postulate", recognize that Mert Root was a great man that, like many others before and after him, changed the course of the podiatric profession for the better, in many cases. However, if his disciples, who are still living, continue to slow down the progress of biomechanical growth of knowledge within the podiatric profession by making every effort to glorify this one man, Mert Root, then our mutual goal of improving worldwide podiatric biomechanics knowledge will certainly suffer.
     
  27. rdp1210

    rdp1210 Active Member


    Thanks for your most civil reply. Believe it or not, Kevin, I'm well aware of Mert's flaws and his dogmatic approach, and I will not attempt to defend such. I do agree that dogma does not move any scientific inquiry forward. How Mert and the true gentleman, John Weed, ever practiced in harmony for so many years, I'll never know. John was truly the academician of the group. I have tried (others will have to judge my success) in following the style of John Weed. I learned a great deal as a student when John softly corrected me when I criticized a practitioner for poor judgment. I have not forgotten. Interestingly enough, the one person that Mert would listen to was Milt Wille. I'm sorry that you never got to know Milt, as I'm sure that you would have loved him and his style. Fortunately Milt was willing to challenge Mert from an experimental point of view, and Mert took him up on it. Milt's successful challenge to Elftman's osseous locking of the MTJ held up Mert's book from a 1975 to a 1977 publication date. I wish that Mert had been able to fund more research by Milt.

    Contrary to what Simon says, I have every interest in moving the biomechanics agenda forward. As you are well aware, I was the first person, independent of you, to publish an article supporting your STJ axis ideas. Simon accuses me of being illiterate because I don't own any of the books you have written. I do have all the peer reviewed articles you have written, and have read the chapter you and Eric wrote in Albert's new book. I had no arguments with that chapter, as it was all very logical. In fact, many of the modifications suggested I have utilized for years.

    I have chosen the Root Postulate as the place to really start because after hours and hours of discussion with the disciples of Schuster -- who was no slouch in his biomechanics knowledge -- I find that it is the Root Postulate that separated the east and west coast of the U.S. I'm not sure that Root or Schuster ever identified what their real differences were. I feel bad that such happened.

    I continue to read the new literature, trying to separate the chaff from the wheat. There is still a great amount of chaff as people utilize poor methodologies and make jumps from results to conclusions. One of the people that does great a job of research is Howard Hillstrom. (TCPM's error in letting him go will go down in history with the same import as Boston letting Babe Ruth out of town) One important concept is the term, "normal", which, as Eric Lee pointed out with great clarity, can have different meanings. I am continuing to look for technology that will allow a complete goniometric evaluation of the foot. As you know I take measurements that Root never talked about. Does that make me a Root opponent or supporter?

    Of great importance to me is the diabetic biomechanics literature. I receive a pub-Med notification weekly of such. In Vancouver I will be presenting some ideas on orthotics for diabetics, that some may see as Not-Root. I continue to look clinically at pedobarographic studies of patient's wearing various orthotic modifications, which is a great way to either prove or disprove the biomechanical theory on any one patient. I don't write as many opinions as you do because I have a heavy clinic schedule as well as other things in my life to keep my attention. But I am involved in active research, a taste of which I presented at Desert Foot in November. Currently my greatest interest is in the further development of the twisted plate theories of the foot. I believe that John Weed was correct, that the main purpose of the in-shoe-orthotic is to control the midfoot, and its action on the STJ is more passive in nature.

    Again, in my Root Postulate thread, I hope that people will contribute evaluations of the Pre-Root literature, and then in part II I would like to see a civil discourse to actually discuss the merits and flaws in the Postulate. I believe that Perkins was a great paper, and that Steindler also was an extremely important person.

    Best wishes,
    Daryl
     
  28. Here is what I actually said:
    "The man is dead, his best work was published forty years ago, the rest of the world and the profession has moved on. Yet, by your own admission, you haven't even read Kevin's books. I should have thought that any podiatrist with a passing interest in biomechanics would have made the effort to read them, let alone someone who positions themselves as a bastion for the old guard; do you not think you should read the literature before you critique it? Moreover, do you not just want to read them in order to be well read in your subject field? I find it astounding that you have not bothered to find the time to read these works, yet you find time to read Rupert Sheldrake- never mind. For the record, I read his "seven experiments" in around 1993."

    I don't think that's quite the same as me "accusing you of being illiterate".
     
  29. Freeman

    Freeman Active Member

    Kevin,

    let me ask a question I believe sure others might be are asking. Is it your theory that a forefoot varus, as compared to a soft tissue supinatus, is as resolvable and can be corrected such that the forefoot becomes de-rotates more or less perpendicular to the rearfoot, but over a longer period of time than soft tissue supinatus?

    Cheers
    Freeman
     
  30. Freeman:

    First of all, when speaking of "forefoot varus" and "forefoot supinatus", we must first realize the technical limitations which come with trying to bisect a calcaneus, trying to reproduce subtalar joint "neutral position" and trying to establish the proper amount of forefoot loading force when taking this "forefoot to rearfoot" measurement as described by Root et al (Root ML, Orien WP, Weed JH, RJ Hughes: Biomechanical Examination of the Foot, Volume 1. Clinical Biomechanics Corporation, Los Angeles, 1971).

    Let's say we all agree that there is an inverted forefoot deformity present, how do we know how much is "structural" (i.e osseous in nature) and how much is "positional" (i.e. the result of abnormal joint position)? My belief is that we really have no way of knowing how much of an inverted forefoot deformity is "structural" versus "positional" because the frontal plane alignment of the plantar metatarsal heads relative to the calcaneus is always going to be dependent on a combination of osseous shapes and joint positions of the subtalar joint, midtarsal joint and midfoot joints.

    Forefoot to rearfoot relationship is partly determined by bone shape and also partly determined by joint position. Since all the structural components of the foot and lower extremity are viscoelastic in nature, and since tendons and ligaments are more susceptible to changes in structure and shape over time due to their decreased stiffness relative to bone, then I believe that the ligaments of the foot will, over time, change their length enough to cause a change in what we call "forefoot to rearfoot relationship".

    Therefore, the forefoot to rearfoot relationship of the human foot is not "set in stone". Rather the forefoot to rearfoot relationship is fluid, not immovable. It will change over time depending on the prevailing external and internal forces and moments acting across the pedal joint axes and the duration of time over which changes within these external and internal forces and moments occur.

    For example, high subtalar joint (STJ) pronation moments, over time, will tend to lengthen the plantar ligaments of the medial column and tend to cause either a more inverted "forefoot deformity" or a less everted "forefoot deformity". Conversely, a high magnitudes of STJ supination moments will tend to shorten the medial column plantar ligaments which will, over time, tend to cause either a more everted or less inverted "forefoot deformity".

    Therefore, instead of asking the question, how do we know if an inverted forefoot deformity is a structural "forefoot varus" or a positional "forefoot supinatus", we should instead be asking the question, in either an inverted or an everted forefoot deformity how do we how much of that "deformity" is structural and how much of that "deformity" is positional? In other words, when we see a 5 degree "forefoot valgus deformity" why couldn't this be a structural 10 degree "forefoot valgus deformity" with a positional 5 degree "forefoot supinatus deformity"?? This is especially an important question to ask given the known large inter-examiner measurement errors that are inherent in attempting to measure "calcaneal bisections" and "forefoot to rearfoot relationships".

    For now, until further research comes along, it is safe to say that every time we attempt to measure a forefoot to rearfoot relationship in a foot that what you are measuring is partly osseous in nature (i.e. structural) and partly due to the current length of the supporting ligaments of the foot (i.e. positional) and that this "forefoot to rearfoot relationship" is likely to change over time when a significant alternation in the magnitudes of external and internal forces and moment occurs on on and within that foot.

    Hope this answers your question, Freeman. See you in Vancouver?:drinks
     
  31. The first thing we need to establish is whether the loading applied did actually generate an instaneous axis about which pronation was occurring across both the TNJ and CCJ- does it?

    Then we need to recognise that there are potentially a multitude of axial positions which might be generated about which pronation like motion may occur simultaneously in the TNJ and CCJ in a single foot; the axial positions being largely due to the vector qualities of the applied force, e.g., point of application, direction, magnitude and the architecture of the joints... Given planal dominance, it then becomes obvious that with the spatial variation of all of these potential axial positions, there is similarly the possibility for multiple "maximally pronated positions" at the MTJ, dependent on the characteristics of the loading applied, spatial location of the axis generated and the bony and soft tissue architecture. If we took a point marker, say attached to the 5th met head, then mapped the position of this marker in the frontal plane for each of the possible MTJ "maximally pronated positions" and then connected the marker points, my guess is that they would map out 1/4 of an ellipse, the geometrical characteristics of the ellipse varying between feet/ individuals.

    Hope that makes sense.
     
  32. Daryl:

    Thanks for the reply. We can both agree now that Mert Root was a particularly dogmatic individual. Maybe Dr. Root was dogmatic because he had to be to do what he did. Unfortunately, the dogmatism Mert Root preached was carried on and copied by many of his "disciples" which probably led to less innovation and less academic debate on the merit of Mert's ideas by others who were simply afraid to lock horns with Mert Root when he was alive. However, I would agree that having John Weed around probably was the best thing for Mert and John since John probably softened Mert's "rough edges" and John was certainly more of the academic.

    As for me, I would rather talk less about Mert Root and talk more about biomechanics of the foot and lower extremity. As such, I will bow out of contributing further to your "Root postulate" thread since I see no point in it because the midtarsal joint doesn't have a "maximally pronated position" and doesn't have a pronation-supination axis. To debate this further, to me, would be like saying "Let's spend time researching who first said that the Earth was flat" and then discuss whether the Earth is indeed flat or round. It is a pointless exercise that I simply don't have the time or interest to participate in.

    When you are ready to discuss biomechanics without mentioning Mert Root's name every other paragraph or so, then I will be happy to take part. However, until that time, I am growing tired of this same old discussion we have been having for the past two decades. I am ready to move on into the 21st century and not continually reflect on one man's accomplishments from four decades ago.
     
  33. Agreed.

    Here is a video I published on YouTube nearly six years ago of me examining my daughter-in-law's foot, stabilizing her ankle and subtalar joint and continually changing the direction and magnitude of input force onto the forefoot. Where is the midtarsal joint axis in her foot?

     
    Last edited by a moderator: Sep 22, 2016
  34. Jeff Root

    Jeff Root Well-Known Member

    Kevin,

    Pronation is abduction, dorsiflexion and eversion. So in order to fully pronate her mtj, all you need to do is move the forefoot to its maximum position of abduction, dorsiflexion and eversion. By the very definition of pronation, this will correspond to the maximally pronated point within rom of the mtj.

    I do agree with you that by altering the direction of force on the forefoot you can produce different quantities of motion in different planes. Is it possible for the mtj to produce pure single plane motion without motion occurring in either of the other two cardinal planes? We don't know, in part because you are moving more joints than just the mtj in the video and there is no way to completely isolate mtj motion. But as I said, if you move the forefoot to the one point in which the forefoot is maximally abducted, dorsiflexed and everted, at the mtj, then you will have reached the open chain end range of pronation at the mtj.

    Jeff
     
    Last edited by a moderator: Sep 22, 2016
  35. I don't agree, Jeff.

    1) Why would someone use the term "pronation"to describe a motion at a joint if there are infinite number of joint axes at that joint, and not just pronation and supination motions being allowed within that joint? Do we ever say the hip joint or wrist joint is "maximally pronated"?

    2) In order to fully evert the midtarsal joint you would need to simultaneously dorsiflex the lateral forefoot and plantarflex the medial forefoot since, as you said, we are moving more joints than the midtarsal joint by using your father's techniques when force is applied to the distal metatarsals. How can you say you are "maximally pronating the midtarsal joint" if you are only placing a dorsiflexion force on the lateral metatarsal heads but not also simultaneously placing a plantarflexion moment on the medial forefoot also?

    3) In order to maximally abduct the "midtarsal joint' one would need to stabilize the calcaneus and put an abduction force on the forefoot which is clearly not what your father described in his neutral position suspension casting technique. How can you say you are "maximally abducting the midtarsal joint" if you are not placing a significant abduction moment on the forefoot by abducting the forefoot forcefully relative to the calcaneus?

    No, Jeff, your father described more a lateral forefoot dorsiflexion technique for neutral position suspension casting. Your father did not describe a "midtarsal joint pronation" technique, as you claim, especially considering that the midtarsal joint does not have a single constrained pronation-supination axis and the input force from the examiner's hands using your father's technique applied to the lateral forefoot mechanically affects not only the midtarsal joint, but also mechanically affects the forces, moments and motions at the metatarsal-cuboid joints, subtalar joint and ankle joint also.
     
  36. Jeff Root

    Jeff Root Well-Known Member

    Kevin,

    Even if a joint is capable of other types of motion, it is very appropriate in biomechanics to describe the motion of simultaneous abduction, doriflexion and eversion as that of pronation. I would encourage you to look into the biomechanics of the elbow, especially as it pertains to baseball throwing injuries to see that this is in fact a common practice in biomechanics.

    I don't understand your first sentence. If you dorsiflex the medial column and plantarflex the later column, this would result in inversion of the forefoot (mtj) in the frontal plane. Inversion is a component of supination.


    If you read what I wrote yesterday, I did say that in some cases my father did advocate stabilizing the calcaneus during casting. However, in most cases it is not necessary as you can "pronate" the mtj via his technique without inducing stj pronation due to the difference of the orientation of the stj and mtj axes.


    Now we are actually having a productive discussion!!! Does applying a pronation force to the lateral forefoot fully pronate the cc joint and the tnj? This is an interesting question. Root thought it did. He believed that when the foot was placed in the casting position that I described yesterday, that mets 2-5 were fully dorsiflexed and the mtj was fully pronated, and that the 1st ray most often, but not always, stayed in or very close to its neutral position. This loading of the lateral column is an interesting topic as I think he was basically right that grf would bring the foot to this position and that an orthosis helps stabilize the foot, in part, by supporting the lateral column.

    Jeff
     
  37. I changed it. My mistake. Thanks for pointing it out. Here's the way it should have read.

     
  38. Applying a dorsiflexion force of 5-10 pounds, as your father suggested, does not fully dorsiflex the lateral column since the lateral column will certainly dorsiflex further when it bears 10-20 times that magnitude of force during running. In addition, as I said earlier, dorsiflexing the lateral forefoot does not "maximally pronate" the midtarsal joint because 1) the midtarsal joint does not have a single pronation-supination axis and 2) the midtarsal joint easily has more available eversion and abduction motion and even dorsiflexion motion available if only the correct directions and magnitudes of input forces onto the forefoot are applied.

    Here's a question for you, Jeff. If the forefoot has a ellipsoid-shaped envelope of motion relative to the rearfoot, as clearly shown in my video, at which of those infinite number of points along that ellipsoid should the midtarsal joint be considered to be "maximally pronated"?
     
  39. Jeff Root

    Jeff Root Well-Known Member

    At which of the two points in the ellipsoid path of motion on your video would you say the forefoot would be most pronated at the mtj, when the forefoot is at the most adducted, plantarflexed and inverted position point or when the forefoot was at the most abducted, dorsiflexed and everted point? I chose the second option.

    Jeff
     
  40. Your video illustrates my point well, Kevin: any of those postions in the ellipse of the movement pathway between 9 o'clock and 12 o'clock (in the case of a right foot; 12 and 3 o'clock in a left foot) could be described as "maximally pronated". I've often thought that it might be interesting to plot the orbit of a point around the ellipse and then define the ellipse in geometric terms of it's long and short axis. This could be done with basic motion analysis software, the kind of stuff you can download for free. Very similar to the approach of Demp, just applied to a different part of foot anatomy and function.

    I also agree that the casting technique described by Root was a " dorsiflexed lateral column" technique, if direct dorsiflexion load was applied to the metatarsals. This is the other point I was hoping to make.:drinks However, if the loading is applied via the examiner by dorsiflexing the lateral three toes (as Jeff stated), then surely their corresponding metatarsal heads "will move downward" as Hicks stated, and the metatarsals will be moved into plantarflexed positions via the windlass mechanism in accordance with the observations of Hicks?
     
    Last edited by a moderator: Sep 22, 2016
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