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Foot orthotics and postural stability

Discussion in 'Biomechanics, Sports and Foot orthoses' started by NewsBot, Jul 23, 2006.

  1. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1

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    The Effect of 6 Weeks of Custom-molded Foot Orthosis Intervention on Postural Stability in Participants With >/=7 Degrees of Forefoot Varus.
    Clin J Sport Med. 2006 Jul;16(4):316-322
     
  2. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    I wonder how many years it took them to find that many subjects with forefoot varus? - given how rare it is....
     
  3. StuCurrie

    StuCurrie Active Member

    Good point Craig, the incidence of forefoot varus varies widely depending on how you are looking at it and who's doing the looking:

    - 8% of 116 female subjects (McPoil et al, 1987)
    - 86% of 120 male and female subjects (Garbalosa et al, 1994)

    From the full text of this article:

    "FV was assessed according to the method established
    by Root and modified by Elveru. The measurements
    were taken with the participant in a prone position
    with the foot held in STJ neutral position by the
    examiner."

    It looks like they were basing their work in part on two studies that have recently investigated the effect of foot structure on Postural stability:

    Cobb SC, Tis LL, Johnson BF, et al. The effect of forefoot varus on
    postural stability. J Orthop Sports Phys Ther. 2004;34:79–85.

    Hertel J, Gay MR, Denegar CR. Differences in postural control
    during single-leg stance among healthy individuals with different
    foot types. J Athletic Training. 2002;37:129–132.


    Cobb reported significantly decreased anteroposterior
    postural stability in participants with >7 degrees of FV
    compared with participants with <7 degrees of FV.

    Hertel however, did not reveal significant postural stability
    between participants classified with pes planus foot
    structures compared with those with pes rectus foot
    structures.

    Regardless of the varus issue, I think there are some interesting findings in this article with regards to FO's and postural stability.

    Has anyone else noticed that the FOs used in this study were Sole Supports? :)

    Stu
     
  4. Sure. Isn't this the same study you refer to in the Snake Oil thread?
     
  5. StuCurrie

    StuCurrie Active Member

    No, this is another article. The "snake oil" post refers to an article on plantar pressures, this one is on postural stability.

    Different articles, similar authors - both studies came out of Georgia State University.
     
  6. Right. Same patients, same products, just different objectives? Could you supply as per the snake oil request - reviewers and their comments please?
     
  7. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    Forefoot varus is rare regardless of who is looking. Garbalosa did not load the forefoot in his study ...duh? and McPoil did not exclude forefoot supinatus from theirs.

    Its obvious that the above study was not looking at forefoot varus, but the mostly the soft tissue contracture of forefoot supinatus .... very different beasts.... very different orthotic designs needed..., yet the authors chose to make a conclusion about forefoot varus.
     
    Last edited by a moderator: Aug 23, 2006
  8. Sell me a God, it's love time- again.

    Anyone else noticed how the beta error of studies using such low sample sizes is in all probability so high that the probability that the authors came to the wrong conclusion is greater than the probability that they came to the right conclusion?

    Anyone else noticed how Ed Glaser has a new salesman on his team?

    Perhaps Stu, you could tell us a littel about yourself?

    Anyone else feel the need to swear?

    Think of me as the Gordon Ramsey of Podiatry, or the big brother of UK Big Brother 2006 winner Pete: "w@nkers" 'nuff said.
     
  9. asyrja

    asyrja Welcome New Poster

    Simon, I will let you know when Ed has new Sales People on his team. Right now that is myself and one other. Stu keeps to the research, he is horrible with sales :)
     
  10. Thanks, seems he's horrible with academic questions too. Could you let me know when you have a "question answerer" on your team?

    Or perhaps since you are posting here you can take that responsibility? Could you tell me the beta error of the study comparing orthoses?

    Hint: Try googling "statistical power"
     
  11. This is not incidence, it's prevalence. Not the same.
     
  12. StuCurrie:

    Is this you?? http://www.psychologistsusa.com/Psychologists/Currie.html

    Any podiatric training??
     
  13. StuCurrie

    StuCurrie Active Member

    Mark,

    As I was not involved with this study (or the plantar pressures study) as an author, the information you request may be a little bit difficult to come by. I do think the reviewer's comments would be good stuff for this forum though, so I've sent a request to one of the authors to see if this is something I can get my hands on.

    I have many questions too. Why the forefoot varus emphasis?

    Thanks for your interest,
    Stu
     
  14. I would have thought that was a question you neeeded to direct towards the authors.
     
  15. StuCurrie

    StuCurrie Active Member

    Craig,

    I hope I didn't imply that I feel that forefoot varus is common. I would agree that the prevalence is much closer to 5% than 87%. Seems to me that forefoot varus can be grossly over-reported due to a few factors, one of which is the subtalar neutral off weightbearing measurement of the 2:1 inversion/eversion ratios. Garbalosa reported high interrater reliability with these ratio measurements, but from what I understand they didn't erase the bisection marks from measurement to measurement??? Kinda takes the punch out of interrater reliability.

    You covered this topic well in the "posting for forefoot varus" thread.

    I agree that this study did nothing to differentiate or account for forefoot varus vs. forefoot supinatus. Do you think that this renders all of the conclusions from this study invalid? Meaning, no matter what it's called (forefoot varus, supinatus, rigid or flexible deformity, compensated or uncompensated varus) it’s still a foot. My thoughts are that although the conclusions regarding forefoot varus and postural stability lose some of their luster, one can still conclude that FO intervention improved postural stability over time (albeit only in the study group with greater than 7 degrees of forefoot varus). Studies with more subjects are definitely needed.

    I’d love to hear your thoughts on the mechanoreceptor function and adaptation period discussion in this article.

    Respectfully,
    Stu
     
  16. achilles

    achilles Active Member

    Randomized clinical trial into the impact of rigid foot orthoses on balance parameters in excessively pronated feet.
    Rome K, Brown CL.
    University of Teesside, School of Health and Social Care, Centre for Rehabilitation Sciences, Middlesbrough, UK. K.Rome@tees.ac.uk

    OBJECTIVE: To evaluate the effect of rigid foot orthoses on balance parameters in participants with clinically diagnosed excessively pronated feet. DESIGN: Randomized clinical trial. SETTING: University biomechanics laboratory. PARTICIPANTS: Thirty female and 20 male healthy participants (mean 23.8+/-2.2 years old) with excessively pronated feet, according to a validated foot classification system were randomly assigned to either a control or intervention group. INTERVENTIONS: Balance testing was performed using the Balance Performance Monitor with an over-the-counter rigid foot orthoses. MAIN OUTCOME MEASURES: Standing balance in the form of mean balance (measures the participants ability to stand with an even load), medial-lateral sway and anterior-posterior sway. All participants were measured while standing bipedally. RESULTS: There was no significant mean difference in balance scores between the control and intervention group at baseline. After four weeks the results demonstrated no significant differences between mean% balance (p >0.05) and anterior-posterior sway (p >0.05). However, there was a reduction with the intervention group in medial-lateral sway (p=0.02). CONCLUSION: The use of foot orthoses in the current study may have improved postural control by stabilizing the rear foot and thus maintaining balance. By the same argument, the benefits of limiting excessive foot pronation may contribute to effective control of internal rotation of the tibia and thereby reduce counter-rotatory motion at the knee and lower leg and maintain balance.
     
  17. I think what really renders the conclusions from this study invalid is the lack of statistical power and flaws in the methodology.
     
  18. StuCurrie

    StuCurrie Active Member

    Hi Simon,

    I hope you will give me a chance to answer some of your questions before you pass judgment. I do hope to engage in some debate, but I’m not all that interested in bickering.

    You had a lot of questions, and I’ll try to answer them as best I can.

    Simon, I have no doubt you know quite a bit about research in this field. What I was referring to was the years of data collection that has been done at Georgia State leading up to this article and many others that are to follow. I am hearing from the authors, they have a massive database of kinematic data that describes how the orthotics work in 3D, and it took one year just to set up the points and model the equations for the study.

    So let’s talk about the stats a bit here. And if this turns into a “big picture debate”, then maybe it’s more appropriate for a new stat thread unrelated to specific articles. I notice that there may be a similar debate going on in the “plantar fasciitis treatment” thread.

    First I should say that I don’t claim to be a superstar statistician, so maybe I’ll learn something along the way.

    You ask about the beta error and statistical power. Stat power was over 0.6 for the study comparing orthoses. Not the best, but not the worst I’ve ever seen either. The stats were run by the biostats consultant for the university. There were no questions on power from the reviewers at CJSM.

    I understand beta error or type II error to be the chances that you are not rejecting the null hypothesis when the alternative hypothesis is true (whew, that’s a lot of double negatives). The null hypothesis in these two studies being that there is no significant difference between the study groups or that there were no differences in the two orthotics groups.

    In other words, this type of error is the chance that you’ll miss the true effect (i.e. declare that there is no significant effect) when it really is there. The rate of false negatives.

    So then, if we are discussing the beta error for this study, I think we are saying that there is a 30 something percent chance that there actually was a statistically significant difference between the two groups being measured that may have been missed.

    In summary, (when talking about beta error only) aren’t we just saying that with these two studies, there is a decent chance that the findings of statistical significance between the two groups were underestimated? Now I realize we are only talking about beta error here, but otherwise the confidence levels and p values look pretty good for most of the results.

    Moving on,

    Are you saying you do not approve of the Clinical Journal of Sports Medicine, and the Journal of Sports Rehabilitation? I know they’re not the NEJM, but I thought they were pretty rigorous with their peer review.

    Which I guess brings up that bigger debate, one that is being covered in another thread. I thoroughly enjoy this forum and all of its threads, and the tendency when discussing issues in academia is to quote articles and research. What standards do we hold the journals to for discussion in this forum? I have read the CONSORT standards posted by Craig and I agree that sample sizes for trials need to be planned carefully, with a balance between clinical and statistical considerations.

    I have copied a quote from Kevin Kirby in that thread:

    "

    Simon, please don’t get me wrong. I am not saying that these studies are beyond reproach, the best ever produced, and that they prove beyond all reasonable doubt that postural stability is changed by a foot orthotic. What I am saying is that I think they are decent studies, done in decent journals, by ethical authors in university departments with good reputations and something worth discussing in this forum. I think we all agree that with a bigger study, the power would go up and the type II error would go down and we would have a better study.

    Respectfully,
    Stu
     
  19. StuCurrie

    StuCurrie Active Member

    Hi Kevin,

    Nope that's not me, but I bet that guy is wondering why his website is getting so many hits lately. I'm a DC (chiro) by education with a background and continuing interest in lower extremity biomechanics and a practice in Denver. No formal podiatric training, but I hope that won't preclude me from posting here. :)

    Stu
     
  20. admin

    admin Administrator Staff Member

    The opposite is the case - we want people of different backgrounds contributing and challenging.
     
  21. StuCurrie

    StuCurrie Active Member

    This study is discussed in the Cobb article. I've copied some of the discussion for those that haven't sifted through the full text:

    The improvement over time in AP PS in the current study but not in the Rome31 study may be related toseveral factors in addition to the differing statistical designs. First, the length of time between the initial test
    and retest differed between the studies. Perhaps improvements in AP PS secondary to FO intervention do not FIGURE 5. Representative scatter plot of ML RMSCOPV versus AP RMSCOPV for the initial PS assessment [subject 2 left foot eyes closed position ()FO condition]. Further study with multiple retest periods would be required to definitively answer this question.
    Another factor may be differences in the construction of the FOs used in the 2 studies. The custom-molded FO used in the current study provided all of its support through the MLA. The prefabricated FO used by Rome31 incorporated rear-foot and forefoot posting to control foot function. The support directly under the MLA provided by the custom-molded FO used in the current study, as opposed to indirect control through rear-foot
    and forefoot posting, may have provided additional support to the MLA through increased arch structure stiffness. As the center of gravity line traveled anteriorly and posteriorly during single-limb stance, the custommolded FO may have provided greater foot stability. In addition to differences in FO construction, the FOs used in the current study may have provided greater stability because they were custom-molded and fabricated to each participant’s foot. The FOs used by Rome31 were prefabricated and each participant received the same degree of forefoot and rear-foot posting. The unexpected result from the current study was the significant AP and
    ML PS improvement over the 6-week period during the ()FO and (+)FO conditions. Unless the FO intervention also resulted in permanent, or at least
    transient, change in foot structure over the 6-week time interval, neither of the above mechanisms account for the improvement reported during the ()FO condition.
     
  22. StuCurrie

    StuCurrie Active Member

    Hi Mark,

    Sorry, I don't think we're going to be able to discuss these. The author doesn't keep these comments on file, and feels it is a breach of reviewer ethics to discuss them, especially when they are addressed in the revisions. I can understand her point of view, considering she is a reviewer herself.

    Stu
     
  23. >60% power with 17 subjects now that is impressive, could you show me the calculation, with specific reference to the effect size calculation and the probability of detecting a clinically relevant difference please? Then we can discuss it more.
     
    Last edited: Aug 26, 2006
  24. We seem to be talking about two papers here. From the paper on plantar pressures:

    "The results of this study suggest that the effect of custom-molded orthotics on plantar pressure might not be evident until after a period of accommodation and that forefoot- and rear-foot-posted orthotics (PAL) might affect plantar pressures differently than mediolongitudinal-arch-supported orthotics (SOLE). The SOLE orthotic appeared to be more effective in achieving the goals of custom-molded orthotic intervention, which include decreased pressure on the lateral metatarsal heads and increased pressure under the first metatarsal head at toe-off."

    Anybody else have problems with this conclusion or is it just me?

    If I have a patient with an ulcer sub 1st MTPJ the "SOLE orthotic would be more effective in achieving the goals of custom-molded orthotic intervention" apparently. :confused:

    Here's an alternative conclusion that could have been drawn:
    Patients with pathologies related to excessive pressure beneath the 1st MTPJ should not use SOLE orthotics.
     
  25. achilles

    achilles Active Member

    Stu,
    As I don't have access to the article, could you please elaborate on the above.
    Enjoying your contributions
    Excellent debate!
     
  26. Stu, what this really means is that assuming the beta error you report is correct, there is a >30% probability that the conclusion drawn by the authors was wrong. It doesn't take a genius to work out that as we approach 50%, we might as well flip a coin.


    As you know, I didn't comment on the Clinical Journal of Sports Medicine, which is index medicus linked. My comment was made with regard to the Journal of Sports Rehabilitation which is not, hence in the schem of things is a weak journal. In my experience peer review can be somewhat of a lottery; depends who is sent the manuscript for review.
     
  27. krome

    krome Active Member

    Hi Everyone

    The study we conducted in 2004 used a pre-fabricated FO. The reason for the design was based just simple on the most common type of FO manufactured by the UK s company at that time. We were surprised by the results so we have conducted further trials. A paper that is soon to be published in Gait & Posture demonstrates that in 40 older female patients with standardised footwear that flat insoles (control, grid, dimple and plain, n = 10 for each condition). The results demonstrated no significant difference in postural stability and comfort after 4 weeks. We are currently conducting two other studies relating to foot orthoses and postural stability:
    1. Evaluating pre-fabricated rigid orthoses with a textured insole in older adults with standardised footwear.
    2. Evaluating the muscle activity of different insole materials on postural stability in older adults
     
  28. achilles

    achilles Active Member

    Kevin Kirby in another thread stated;
    Does this apply here???? ;)

    Tony
     
  29. Stu:

    Welcome to Podiatry Arena, Stu. I have enjoyed your postings so far as you seem to not need to be constantly marketing Sole Supports orthoses as Ed Glaser has done in many of his previous postings to Podiatry Arena. It would be interesting to get more chiropractors in this forum.

    Even though I'm sure there are good chiropractors in my area, chiropractors in Northern California don't seem to know much about foot orthoses since all the ones in my area make this device called a "Foot Leveler" which looks like a patchwork of pads and wedges all glued between two pieces of leather to make what they call an orthosis. They are really pretty useless as far as I can see since they don't match the contours of the foot and my patients have told me that they were quite expensive but not helpful.

    Why do chiropractors use these "Foot Leveler" devices for foot orthoses? Are you all not trained in proper negative casting technique for foot orthoses in chiropractic college?? What is the theory behind all the bumps and pads on the "Foot Leveler" orthoses?? Are they meant to directly mechanically support the foot or provide CNS stimulation to the sole of the foot???
     
  30. StuCurrie

    StuCurrie Active Member

    You can access the article here: Postural Stability

    One of the things about this study that I found interesting was the improvement in postural stability after 6 weeks with an orthotic, even when the test was done without the orthotic in the shoe. There was an inmprovement in postural stability after 6 weeks of orthotic wear in BOTH the +FO and -FO test conditions. In the discussion section the authors theorize on the mechanisms of this finding:

    Perhaps then, the primary benefit of FO intervention
    on PS (postural stability) was related to improved mechanoreceptor
    function secondary to the increased contact area between
    the FO and the plantar surface of the foot.4,31 If improved
    mechanoreceptor function was the mechanism, the results
    of the current study would suggest that there is an
    adaptation period during which the improvement in
    mechanoreceptor function occurs.

    I was interested in hearing thoughts on this mechanoreceptor function theory. Maybe KROME could comment on whether he found any similar adaptation period in any of his postural stability studies.

    Stu
     
  31. StuCurrie

    StuCurrie Active Member

    First, sorry we are jumping between the two papers. I stopped posting in the other thread mostly because I figured the debate was similar.

    I can see your point Simon, the authors of the plantar pressures study were basing their conclusions on the ideal dynamic gait line pattern as identified by Root.

    They identify the goals of a FO:
    "The goal of a custom-molded and -fabricated orthotic is to attempt to shift the path of plantar pressures from a potentially pathological force curve to one that more closely resembles the force curve described by Root et al."

    They base their conclusion on the fact that with a varus deformity (soft tissue) they saw force being transferred to the central or lateral metatarsal heads at heel lift. With the SOLE orthotic, those lateral forces were decreased.

    Stu
     
  32. StuCurrie

    StuCurrie Active Member

    Isn't it more accurate when speaking of beta error to say that there is a >30% chance that the authors missed a statistically significant difference between the treatment groups? To me this is not the same as saying the conclusions were wrong.

    You do a good job of summarizing the statistics in the "PF treatment thread" and I think much of this debate is the same so I won't repeat the argument here.

    I do think the following applies to the conclusions drawn from this study and the debate about power and beta error in general:

    From a definition on type II error - A beta error is only an error in the sense that an opportunity to reject the null hypothesis correctly was lost. It is not an error in the sense that an incorrect conclusion was drawn since no conclusion is drawn when the null hypothesis is not rejected.

    Stu
     
  33. StuCurrie

    StuCurrie Active Member

    Well, I think we've hit the end of the road as far as a stats debate on the postural stability article goes. I'm sorry, as I wasn't involved as an author or a stats guy in this study I don't have access to the exact calculation.

    I do know that the number crunching on this study was done according to well established university protocols by a stats consultant and checked by a biostatistician - which is more than I can say for many studies I read. From what I understand from the authors, calculating a stat power of .8 can only be done for univariate statistics, and you can only estimate power for multivariate statistics like the ones in this study. The power was calculated on a univariate model of .6 because the estimated power on a multivariate model would be considerably higher. Otherwise the beta error would have been obscene because of using repeated univariate measurements. I hope this helps.

    I will say again, that I am not saying a study with a larger “n” wouldn't have been better, but I think many of the studies discussed in this forum have similar numbers of participants.

    To get a better feel for what is commonplace, I looked at the studies reported in the latest JAPMA issue. I found subject numbers of 16, 440, 44, 33, 24, 22, 40 and 14. I don't think anyone would argue that we should toss away this issue of JAPMA because of low n's.

    Also, I noticed that in your preliminary report published in JAPMA on the Subtalar Joint Axis Locator, you used 2 subjects. I understand that it was a preliminary report, and you say in your discussion -

    "Although the sample used in this preliminary study was too small to draw definitive conclusions, the results obtained from the two subjects used in the radiographic study were very encouraging."

    To me, those are not the comments of someone who would refuse to read, or quickly dismiss, studies with a low number of subjects.

    Respectfully,
    Stu
     
  34. Stu,

    Firstly, let me ask you what data did Root et al. provide to support their contention?

    Secondly, do you think it would be beneficial to increase the sub 1st loading in an individual with forefoot supinatus?
     
  35. From the example I gave in PF treatment thread, in two of the four cases the researcher will be wrong, having reached either a false positive or a false negative conclusion. How can this not be considered as arriving at the wrong conclusion and that the researchers conclusion was wrong?

    I don't understand why you think that no conclusion is drawn when the null hypothesis is not rejected :confused:
     
  36. Never heard this before, can you supply a reference?
    Here is a source which shows that it can be performed for multi-variate ANOVA as was used inthe study:
    http://www.psycho.uni-duesseldorf.de/aap/projects/gpower/reference/reference_manual_07.html

    What you seem to be saying here is that power was not calculated correctly for the analyses performed. Since sample size calculations depend on the method of analysis this appears erroneous.


    Doesn't make them any better I''m afraid.

    Doesn't make things any better I'm afraid. Only one likely to be up to power.

    The pilot study published in JAPMA was massively under powered, hence the massive caveat in the text and the preliminary in the title. Could you point to similar caveat's in the studies under debate re: sample size as I still haven't had chance to read them thoroughly- I may have missed them?

    With respect, you clearly don't know me. Tried looking for something you had published, but couldn't find anything. ;)
     
  37. krome

    krome Active Member

    Hi

    First of all it is interesting to read the debate about power calculations and methodological issues. It is major problem in clinical research to recruit sufficient patients. Many times it is difficult to conduct power calculations due to a lack of previous evidence. If there is previous evidence the numbers are impossible to recruit due to financial and time constraints. I feel that people who conduct research and disseminate their findings to the public domain should be congratulated not criticised.

    The role of foot orthoses in postural stability relates to the function of the mechanoreceptors on the plantar surface of the feet. Lots of research conducted in this area [1-5]. It is likely that plantar mechanoreceptors participate to the feedback control system regulating body sway oscillations as they are related to different parameters of ground reaction force which are indirectly related to COP displacements. Foot orthoses may enhance or maybe detrimental to this process and I believe it is related to the material and the shape of the foot orthoses – contoured possible being better than a flat insole. However, more research is required.

    1. Maki BE, Perry SD, Norrie RG, McIlroy WE. Effect of facilitation of sensation from plantar foot-surface boundaries on postural stabilization in young and older adults. J
    Gerontol A Biol Sci Med Sci 1999;54:281–7.

    2. Perry SD, McIlroy WE, Maki BE. The role of plantar cutaneous mechanoreceptors in the control of compensatory stepping reactions evoked by unpredictable, multi-directional perturbation. Brain Res 2000;877:401–6.

    3. Kavounoudias A, Roll R, Roll JP. Foot sole and ankle muscle inputs contribute jointly to human erect posture regulation. J Physiol 2001; 532:869–78.

    4. Meyer PF, Oddsson LI, De Luca CJ. The role of plantar cutaneous sensation in unperturbed stance. Exp Brain Res 2004;156:505–12.

    5. Bensmaı¨a SJ, Leung YY, Hsiao SS, Johnson KO. Vibratory adaptation of cutaneous mechanoreceptive afferents. J Neurophysiol 2005;94: 3023–3026
     
  38. StuCurrie

    StuCurrie Active Member

    Hi Kevin, thanks for the welcome.

    Your question is a great one, and one that I'm not sure I can provide any insight into from a biomechanical standpoint. You see, I've never been able to determine exactly what the Foot Leveler orthotic is supposed to do. You will read catch phrases like "spinal pelvic stabilization" or "supports all 3 arches of the foot" but there's no satisfactory explanation that I've ever come across. At least no explanation in terms that podiatrists and other biomechanically inclined people would get on board with.

    As with a lot of products out there, my best guess is that any beneficial effect is achieved through mechanoreceptor stimulation rather than any direct mechanical support. You're right, when you open them up and look inside they are basically a few pads sandwiched between two pieces of material. There is usually a bump in the area of the met heads, so that may also provide some benefit to a certain patient population.

    Unfortunately, the ordering and casting of this product does not stand up to biomechanical scrutiny in my opinion. On the order form, you are able to check off various diagnoses and then the patient does the old "step in the box" routine and voila - your pair of "custom made" orthotics are on their way.

    So back to you question - Why do some chiropractors use these devices? I might be able to provide some insight into that. Foot Levelers has a very big presence in the chiropractic community (much to my chagrin). They make a lot of philanthropic donations to various pro chiropractic organizations and have a slick marketing campaign that includes a decent speaker's bureau. I don't know the size of the company or how many orthotics they make, but when a company is donating 1 million dollars here and there, they must be doing OK. There are Foot Levelers scholarships to various chiro schools, they raised 500K in matching donations for hurricane Katrina, there have been million dollar donations to chiro schools for building expansions. etc. etc. So from a purely financial standpoint they are great for the profession.

    My own skepticism of the product began in school, when we were given a free pair to try (a variation on McDonalds' get 'em while they're in their formative years strategy). A few of us decided to run our first "scientific" study and we sent in orders for all different types of orthotics, from big feet, to small feet, to rigid feet, to floppy feet, checking off diagnoses such as "lumbago", "sciatica", and on and on. Well, guess what - we all got pretty much the exact same orthotic back. Different colors, maybe a few different bumps, but the same flexibility and overall structure. Simon, I'm not sure what the beta error on that study was but it was enough proof for me. :)

    So that's the long version of the story. I guess the short answer to your question would have simply been.........money.

    Interestingly, Georgia State University has recently informed me that part of the database they've been building involves comparisons of the Sole Support orthotic to the Foot Levelers orthotic. I don't know anything about the studies, and didn't even know they were happening, but I expect the results to be interesting.

    Hope that helps,

    Stu
     
  39. Stu:

    Thanks for your candid reply. The information you have provided here confirms my suspicions as to why any intelligent health-care professional would use such a poorly-shaped and poorly-functioning device (such as the Foot Leveler orthoses used by chiropractors) as a custom foot orthosis for their patients. In other words, they either don't know any better or haven't been trained properly on custom foot orthosis therapy and figure they might as well make money on foot orthoses by selling them to the unsuspecting and ailing public.

    Along these same lines regarding orthosis companies that sell and promote their own products to health professionals, I have now had the opportunity to see 3-4 Sole Support orthoses in my office from patients who have either had minimal to no positive results or are having increased symptoms on their asymptomatic side from the use of Sole Support orthoses. I have yet to see a patient that has had positive results from Sole Support orthoses.

    From viewing the DVD that Ed Glaser mailed in bulk to my office and the offices of hundreds, if not thousands, of podiatrists here in the US (with none of us ever requesting this DVD), from reading his comments to Podiatry Arena, and from reading the propoganda in his Sole Support website, Ed seems to think that all pathologies in the foot are caused by excessive pronation. Unfortunately, this myopic approach to foot orthosis therapy causes real problems when the patient has a fairly normal STJ axis location and the increased STJ supination moment caused by the excessively high arched orthosis (like the Sole Support orthosis) causes the patient to develop increased peroneal muscle contractile activity and develop peroneal tendinitis. In other words, the last patient that I saw yesterday that had received these excessively high arched orthoses made by Sole Support (from a podiatrist practicing here in Sacramento) was now developing peroneal tendinitis on his asymptomatic foot from the Sole Support orthoses. He thought the podiatrist that prescribed these Sole Support orthoses to him was trying to hurt him!!

    So you see, in my opinion, it is not just chiropractors who don't know what they are doing with foot orthoses by using Foot Leveler orthoses. Many podiatrists that are also ignorant as to what makes a good orthosis from a poor orthosis. It is this ignorance that makes them susceptible to the sales pitch that a few select podiatrists make to the profession on the "magical benefits" of their company's (and their company's alone) prescription foot orthoses. These few select podiatrists often give "academic" biomechanics lectures which are nothing more than thinly-veiled marketing seminars for their company's orthosis products. It is sad, but unfortunately, true.
     
  40. Sole supports

    I'm going to go out on a limb here. Kevin your last post made me feel uncomfortable. I disagree. :eek:

    I agree that the Mass system has holes in it's rational through which you could drive a lorry. I also deplore the delivery of a sales pitch in the guise of an education event.

    But most of all i mistrust the idea that the experiance of a small number of patients can be said to represent the whole. This is how we get the idea that An orthotic will cure infertility and facial pain (sorry Brian).

    Since we have all been cheerfully ripping holes in people who are pointing to small anecdotal studies as evidence that an orthotic type works surely we cannot then imply that having 3-4 patients for whom sole supports did not work is representative of the whole or that it proves that the paradigm is flawed. The people for whom these insoles DID work, and i'm sure there must be at least a few, would have no reason to seek further consultation with another podiatrist so we will not see the sucesses! And who amongst us knows for certain we have never issued an orthotic which the patient did not get on with and that they then went to another podiatrist and slagged us off?

    If i have misunderstood you kevin then my sincere apologies. However as i said, your last post made me very uneasy! :(

    Regards
    Robert
     
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