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Plantar fasciitis and lateral forefoot wedges

Discussion in 'Biomechanics, Sports and Foot orthoses' started by Kahuna, Feb 11, 2010.

  1. Kahuna

    Kahuna Active Member


    Members do not see these Ads. Sign Up.
    I'm writing a research proposal for QMU,

    During my lit review, I found an interesting piece of research from 1999 that supports the approach of lateral ff wedging in the tx of pl fasciitis:

    [Kogler GF, Veer FB, Solomonidis SE, Paul JP. The influence of medial and lateral placement of orthotic wedges on loading of the plantar aponeurosis. J Bone Joint Surg Am. 1999;81:1403–1413.]

    Their study centred on measuring plantar aponeurosis strain in cadaveric lower limbs using different wedging combinations under the forefoot and hindfoot. They reported that a 6° wedge placed under the lateral aspect of the forefoot demonstrated the greatest reduction in plantar aponeurosis strain.

    Any thoughts??

    From my own experience, I've found (as have many others) that lateral ff wedging helps pl fasciitis sufferers... But I'm interested to know if anyone in the arena has ever taken this as far as a 6° wedge!?


    Thanks...
     
  2. David Wedemeyer

    David Wedemeyer Well-Known Member

    I would think the reasoning behind the use of the wedge would be just as important than the wedge itself. More often the PF patients that I see are pronators and have a medially deviated STJ axis. I also find some degree of forefoot varus, rearfoot valgus assoiciated with the more severe cases and more flexible midfeet. I cannot understand the rationale for valgus forefoot wedging in this patient population.

    I can see where a compensated forefoot valgus in a subtle cavoid foot can lead to PF and where a foot like this probably would benefit from valgus wedging in the forefoot.

    Do you happen to have the study Kahuna?
     
  3. Griff

    Griff Moderator

    I think Craig and his colleagues at La Trobe have shown that lateral forefoot wedging reduces the force required to initiate the windlass mechanism -> this is a good thing in plantar fascia pathology. The rationale? To reduce the pathological loading force on the PF. Can't think of the thread in which we discussed this previously off the top of my head but will link it here when I do. This valgus forefoot wedging is usually used in combination with varus rearfoot wedging.

    David - article attached.

    Ian
     

    Attached Files:

  4. efuller

    efuller MVP

    It's not necessarily the pronation that causes the plantar fasciitis. It's also the high loads sub 1st met and hallux causing a dorsiflexion moment on the first ray. The plantar fascia resists the dorsiflexion moment from the ground. So, a large enough valgus wedge will use up all the range of motion in the direction of eversion and eventually decrease the load sub first met and hallux.

    Regards,

    Eric
     
  5. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    That is indeed the case. We showed that the forces to dorsiflex the hallux are higher in those with plantar fasciitis. Elevating the lateral forefoot lowers the force to get the windlass established ... all consistent with Geza's work. (was only lecturing on it today at the boot camp in auckland!!! - I put this thread up on screen to show them all!!!).
     
  6. David Wedemeyer

    David Wedemeyer Well-Known Member

    Ian, Eric, Craig,

    Thank you for the study Ian and to all of you for the response. I had read the thread previously on this about Craig's findings. Are you saying that a lateral wedge should be used unilaterally in PF patients based on this? How about those with 1st ray dorsiflexion stiffness or can that be addressed with a cutout? Also what about the patients who's primary issue is posterior tibial tendinitis with PF?

    My point was that the goals for some patients will differ based on their individual foot's needs or is that not true?

    I must be behind on my reading again!

    Regards,
     
  7. Bruce Williams

    Bruce Williams Well-Known Member

    I've done 8 degree wedges utilizing my AMFIT scanner and Mill.
    Works just fine.
    Definitely a good tool in many foot ailment treatments.
    Bruce
     
  8. Bruce Williams

    Bruce Williams Well-Known Member

    I have used unilateral FF valgus posting / wedging, but in general use it bilaterally.
    Bruce
     
  9. David Smith

    David Smith Well-Known Member

    Kahuna, David, Eric and all

    Does this analysis help?

    [​IMG]

    Cheers Dave
     
  10. David Smith

    David Smith Well-Known Member

    Oh yeah, sorry, 1st line- that should read STJ axis medial projection.
     
  11. David Wedemeyer

    David Wedemeyer Well-Known Member

    I responded to you Bruce but my post seems to have disappeared! Thanks for responding. I did not express myself clearly when I used the term unilaterally. I should have asked if it is suggested that we use forefoot wedging on every PF patient across the board. My thoughts are that there are patients with PF who display concomitant pathology, where the use of a forefoot wedge may not be suitable. Your thoughts?
     
  12. David Wedemeyer

    David Wedemeyer Well-Known Member

    David

    Bravo! I definitely need to look at this in greater detail.
     
  13. efuller

    efuller MVP

    David,

    One criteria I use to decide whether or not to add a lateral forefoot valgus wedge is a measurement I call maximum eversion height. Patient is standing and you ask them to evert their foot and don't let them move their knees or lower leg. The height off of the floor that lateral foot can obtain is variable across individuals. Some individuals have no range of motion for further eversion and cannot lift their lateral forefoot off of the ground. When you place a forefoot valgus wedge under these feet you can get very high pressures under the lateral forefoot or pain in the sinus tarsi.

    Cheers,

    Eric.
     
  14. David Wedemeyer

    David Wedemeyer Well-Known Member

    Precisely Eric, this illustrates what my original inquiry was. I would also be very careful in laterally wedging a varus forefoot with PT tendinitis. What gain is the from a valgus wedge when the patient already has a medially deviated STJ and a diminished mechanical advantage to resupinate the foot? obviously not all PF patients have this presentation but it is an example of when we need to crticially think about the goals of orthosis therapy. Do we not find this combination along with PF as an initial complaint that over time progresses to PTT or AAFD? Is my logic incorrect?

    Thank you as always for your interest and excellent responses Eric.
     
  15. Bruce Williams

    Bruce Williams Well-Known Member

    David;
    I don't disagree with Eric's evaluation of the lateral column, but in your example above I do disagree.

    Patients wtih PT tendinitis and /or tendinosis benefit greatly from the use of a lateral FF wedge if the PT tendon is still functional and if there has been little or no lateral abduction of the FF on the rearfoot.

    In most, but not all of the feet I have dealt with, significant abduction of the FF on the RF usually has changed the site of midfoot/FF compensation from being primarily in the sagittal plane to being primarily in the transverse plane. Transverse plane deformities usually need bracing of some sort or high top boots wtih CFO's as kevin K. has suggested many times.

    STJ axis theory does not satisfactorily answer the question of why a Lateral FF wedge will work in disorders of this nature or in Plantar fascitis, and that has not been successfully debated by the originator of the theory in my opinion.

    I am not looking to rekindle this discussion or debate, but I suggest you research podiatry-arena for the multiple discussions that have occured regarding this debate.

    Cheers;
    Bruce
     
  16. Bruce Williams

    Bruce Williams Well-Known Member

    David;
    interesting explanation.

    Can you explain to me please why the pressures sub 1st and 2nd mpj increase in most instances with the use of a lateral FF wedge? I know that forces and pressures are not exactly the same.

    Before I once again succomb to one of your more brilliant explanations I want to make sure I fully understand it myself. I hope that you received my email reply a few weeks ago? I asked Craig to forward it to you as the email address you sent me did not work.

    cheers!
    Bruce
     
  17. JDunn

    JDunn Welcome New Poster

    Thanks Eric,

    This makes sense of something that I have often wondered about when I see patients that have a very neutral foot types with minimal pronation.

    At a glance of this thread it seems that ff valgus posting with a neutral foot type with plantar fasciitis would be quite good. This is something that I'll have to read up some more on.


    I would be interested in knowing how many other pod's have been using ff valgus posting for plantar fasciitis, and how many degrees of correction they have been using?
     
  18. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    I use the forefoot valgus post even if there is a forefoot varus present ...as thats what the research tells me lowers the forces going through the plantar fascia.
     
  19. Paul Bowles

    Paul Bowles Well-Known Member

    I agree with this and have seen results suggesting this clinically. If clinically it works and the research suggests it lowers forces through the fascia then its a win win!!!
     
  20. David Smith

    David Smith Well-Known Member

    1) Of course you are right to be sceptical, first, this is a theoretical analysis and real observation may not agree, as you have proposed.

    Lets talk forces not pressure tho because unless the contact areas remain constant the relationship of pressure to moments about a point of interest is unknown.

    There are a lot of 'ifs' to be assumed. IE if the STJ is maximally pronated in the first case then the second case may be likely. If the STJ can pronate more, then there would be additional pronation moments and an angular acceleration would tend to occur that could be balanced by a force causing relative supination moments, which maybe from the 1st, 2nd MPJs and so increase discreet forces there.

    However if in this latter position you were to take out the lateral wedge and yet still keep the same STJ position (say by muscular activity, then the 1st, 2nd mpj discreet GRF would increase. I.E. the same principle applies mechanically but the result may not be desirable clinically.

    Another thing to think about is that the relative moment arm lengths change as you elevate or incline the foot and so the discreet loads change. I.E. ->

    [​IMG]

    There are many variables, including that one, that could be added into the analysis model.

    Bruce, can you be sure that it is always the case that discreet forces sub 1st 2nd MPJs increase when a lateral f/f post in added? Does the timing or the force impulse change?

    I would imagine that if the strain in the PF is reduced then there must be a reduction in load applied and if the total GRF is constant it must be the change in loads on the relative lever arms that stress the PF that have reduced.

    2) No didn't get any emails or PMs from you or Craig. Try this email address david@foothouse.co.uk. I no longer get arena alerts about threads I've contributed to either. Be interesting to hear what you have to say regarding my email questions.

    Cheers Dave
     
  21. Lawrence Bevan

    Lawrence Bevan Active Member

    Hi

    I have pronated feet and I have a significant supinatus, I get symptoms of medial knee pain, ankle synovitis, MTSS and plantar fasciitis.

    If you put (as i have done) a valgus wedge on my orthotics I get more plantar fasciitis. In fact I get more of everything!

    Research has shown an awful lot of things to be "good for plantar fasciitis". So before we get carried down the road of "valgus wedges = good for plantar fasciitis", can we define the tests we use to know that adding a valgus wedge is going to lead to a positive outcome? Is everybody using them in conjunction with a varus rearfoot wedge of some description?

    Eric has proposed the eversion height test, I use this. Anybody got anything else?
     
  22. Lawrence,
    Do you also have a `very´medially deviated axis ?

    If so could not the FF Valgus wedge be adding to the force Vector of the External STJ pronation moment from GRF lateral to the STJ axis and therefore you will get a greater degree of STJ pronation and more PF load and I´m just thinking ouload on this point less of a windlass but greater negative windlass ?

    So the FF eversion testing that Eric discusssed must be considered in relation to the position of the STJ axis. There must be at least the 1st ray and 1st MTP joint lateral to the axis to get a greater external STJ supination moment from a FF valgus post. If that what your after ?

    Which is why an effective medial Skive would be the best combination with the lateral FF posting ?But if the medial skive is unable to move the new stj equilibrium point laterally enough the FF posting will not have this positive effect of the windlass mechanism?

    Am I thinking correctly ?
     
  23. Bruce Williams

    Bruce Williams Well-Known Member

    David;

    I'm more inclined to follow your example of lever arm length and incline angle or positioning of the foot.

    Timing and force impulse make a huge difference as well. I would have to run all of my files thru an exam to determine if the majority of the forces sub 1-2 increase with FF valgsue wedges, but I think that is what my eyes have been showing me for quite a while adn that is one of my primary goals when I treat utilizing in-shoe pressure.

    I like that you mentioned the assumption of maximum STJ pronation or it there is more available ROM. I think this is a key if not the key point in most of these discussions.

    Once all available pronation ROM has been utilized in the STJ then, usually after you have used up all the available DFion ROM at the AJ, (pronation ROM too according to Nester) you move distally into the midfoot and FF. Compensations there are limited (again according to Nester) at the midfoot / MTJ, but more motion is apparently available at the metatarsals in DFion ROM.Once all of these compensation motions are maxed out you can only then usually use the knee to gain ROM at STJ / AJ thru flexion.

    The point of this rambling from my POV comes back to timing and positioning and lever arm length as well. What position is the foot, what are the primary muscles doing are they inhibited or active and what effect does this have on normal progression of the foot, leg and body?

    Many more ifs, though just explained a little differently. But, if you assume tht the STJ is maximally pronated and DFion ROM is maxed too, then you will assume that the midfoot / FF will pronate and DF as well. Limited AJ Rom can inhibit the Peroneals and the DF'd position of the FF will lower the lateral column and lengthen the lever arm of the peroneals as well. I think the loss of motion of the Fibula due to adequate DFion will cause or simiulate inhibition of the peroneals as well. All of this leads to a decrease in forces/pressure sub 1st mpj and the inhibition of the peroneals allows the active PT tendon to supinate the foot adn move the CoF/CoP laterally. Adding a Lateral FF wedge in these patients will potentially shorten the lever arm of the peroneals as the foot is pronated in late midsatnac and as the heel lifts positions the STJ for potentially easier supination.
    This allows the plantar fascia to overcome the moments that Eric describes adn allows the 1st mpj to DF and the sub 1st mpjpressues to increase.

    my thoughts on how it works. Still a lot of ifs!
    good discussion.
    Bruce
     
  24. Sammo

    Sammo Active Member

    Fabulous conversation guys..

    However, on another point: Is there anything to suggest increased incidence of dorsal midfoot interossei compression syndrome (DMICS) with the use of the lateral forefoot wedge?

    Could it be that there could be a increase of force across the 4-5th met cuboid joint with the increased GRF under the corresponding metatarsal heads that may cause this problem in the longer term, similar to how varus posting in a pt with genu varum can increase likelihood medial knee OA?

    Doesn't the research on valgus FF posting only look at static force through the plantar fascia with varying combinations of FF and RF varus/valgus posting in cadavers? Or has there been some more research published on the topic?

    Regards and Gong Xi Fa Cai!

    S
     
  25. As well as considering the STJ axis position and possible amount of Pronation available to the STJ ( if I completly understand Bruce and Davids discussion )if a FF Valgus post is used to treat PF. What about the Position of the 1st MTP joint. If there is an HAV deferomity and you increase the load on the 1st to get a greater windlass effect provided by dorsiflexion of the
    1st what effect will an HAV deformity have on all of this ?

    and could this be another thing to consider before using a FF Valgus post in your treatment plan?
     
  26. Bruce Williams

    Bruce Williams Well-Known Member

    In general not a factor when txing HAV.
    Problem with HAV is to little DFion Stiffness and then medial movement of metatarsal adn lateral deviation of hallux.
    Usualy addition of FF valgus post and use of digital pad or cluffy wedge will PF the 1st metahead and decrease or stabilize the current position of the 1st mpj.
    Also, orthotics to tx HAV are iffy in that they add material into the shoe adn can make the pain worse.
    my 2 cents
    Bruce
     
  27. Bruce Williams

    Bruce Williams Well-Known Member

    Sam;
    can you give me a reference on a paper that actually says that varus posting in a patient with genu varum increases the likelihood of medial knee OA?
    I think that is a huge supposition just b/c lateral wedging helps many with medial knee OA.
    One does not necessarily prove the other and at this point I do not recall a paper that has definitively proven your statement. I will stand corrected if there is on, doubtful, but corrected.
    That said, I do not think I have seen anyone suffer from DMICS with the use of alateral FF wedge. I think that tends to be more of a medial dorsal problem after midfoot injury if I am understanding correctly?
    In those patients I try to increase the digital posting, cluffy wedge, to stabilze the DFion stiffness of the metatarsals. Does not always work, often need a hinged AFO as well.
    Finally, the work on FF wedging was done statically. I don't know about Craig's research? Craig?
    Bruce
     

  28. Hi Bruce I was not meaning tx HAV with orthtoics, I thought it was fairly clear maybe not . I was meaning that if you have a PF patient that you would use a Medial skive and FF valgus post, does this place increased pressure on the HAV deformity if there is one ?

    I agree that treating HAV with orthotics is very very iffy

    so treat one thing get more problems somewhere else ?
     
  29. efuller

    efuller MVP

    Hi Bruce,

    I don't know if there is a specific paper that fits your question, but there is a lot of stuff that dances around it.

    The theory on wedging and knee arthritis is that it is related to the location of center of pressure under the foot and the center of pressure between the femur and tibia. Looking in the frontal plan, with a subject with a high amount of tibial varum, the force on the tibia at the knee will be lateral to the force on the tibia from the ground. (Pictures help a lot). This will create a force couple on the tibia creating and adduction moment on the tibia. In static stance, equilibrium must be maintained (Newton's Laws F=ma, a = 0 in static stance). So, in the above subject there is an external adduction moment on the tibia. There must be an internal abduction moment on the tibia. The only place it can be is from increased pressure in the medial compartment of the knee and tension in the lateral collateral ligament. (pictures help). The above theory is supported by the studies that show decreased adduction moment and improved pain with lateral heel wedges. The explanation of the lateral heel wedge is that it shifts the center of pressure under the foot more laterally which decreases the external adduction moment on the tibia. The decreased external moment leads to a decreased internal moment.

    So, there is evidence for wedging changing the amount of force within the knee. If it works in one direction, it should work in the other. I have seen patients with STJ pronation related problems and tibial varum, who I gave a varus heel wedge to and then got increased medial knee pain.

    Regards,
    Eric
     
  30. Bruce Williams

    Bruce Williams Well-Known Member

    Eric;

    I appreciate your description above and your example too. I've seen the same thing in a few patients with advanced medial knee pain.

    The issue for me is the statement that the use of a FF valgus post or a varus heel post for that matter could cause this type of knee pain.

    Has anyone ever had a patient who wore long term orthotics with either or both of the posts above who has ended up with this type of knee pain? Or, is it that patients with medial knee pain come in and they've never had orthotic treatment in their lives until possibly recently and it exacerbated their pain?

    I think this is an interesting question to ask. the idea that posting will cause medial knee pain I think is not definitively supported at all. This is the same as saying running shoes cause running injuries. I think we've seen where that thread has gone!
    :bang:
    Cheers!
    Bruce
     
  31. David Wedemeyer

    David Wedemeyer Well-Known Member

    Lawrence your post mirrors my thoughts on the subject. Certainly we can all appreciate the benefit of a lateral forefoot wedge in plantar fasciitis. Eric's post addresses the mechanism by which dysfunction of the windlass mechanism is caused by a dorsiflxion moment of the 1st met and how lateral wedging mediates those forces.

    Are we assuming then that the majority of PF is then caused by sagittal plane dysfunction alone? Don't we tend to find frontal plane compensations and feet with issues such as Lawrence describes where a lateral wedge is contraindicated? :

    I perform a Coleman Block test on my patients to evaluate for fixed flexion of 1st metatarsal, flexibility vs. rigidity of the hindfoot and available range of pronation . If the block cannot correct the apparent dysfunction I do not use a forefoot wedge.

    But again, what good use is a lateral wedge in every foot with PF? I agree with your query "valgus wedges = good for plantar fasciitis" and add in which feet???????
     
  32. barry hawes

    barry hawes Active Member

    Hi everyone,

    Simon Bartold tested the benefits of lateral wedging for plantar fasciitis in an award winning paper which he presented at the Sports Medicine Australia Conference in Canberra in 1998 (from memory!) The study was an RCT (n=52) comparing 5 degree lat forefoot wedge, 5 degree medial rearfoot wedge, functional foot orthoses and antipronation taping (Simon's own variation on Copeland strapping) on patients with plantar fasciitis. Outcome measure was VAS pain scores measured after 7 days. The lateral forefoot wedging and taping produced significant reductions in symptoms; the functional foot orthoses and medial reafoot wedging did not. (Simon, me old Chinois, if you're out there you may be able to expand on this) Obvious limitations with the duration of the trial, sample size and subjective outcome measure, but a very interesting result. I don't know if this was ever published, but I still have the abstract from the conference.

    I incorporate a small ff valgus wedge into many of the foot orthoses I use for plantar fasciitis and they seem to work well, though rarely with spectacular results after only 7 days

    Cheers and good look with the research proposal,

    Barry Hawes
     
  33. Lawrence Bevan

    Lawrence Bevan Active Member

    Barry

    thanks for that info, interesting. Is it the taping or the forefoot wedge that helps? I can certainly say that if I was looking to make a difference in only 7 days, i would use strapping not a functional orthotic.

    Also if by the "functional" orthotic the study aludes to means polypro I dont tend to use those much now for "plantar fasciitis". I prefer to use a moulded soft orthotic and these seem to work better, even without any posting.

    Does a wedge have to be a "wedge" or can a device with a flat forefoot extension on it of say 3mm EVA/korex under mets 2-5 function in a similar way?
     
  34. barry hawes

    barry hawes Active Member

    Bevan,

    My understanding was that there were 4 groups compared. The strapping group and lateral forefoot wedging groups did well; the functional foot ortho group and medial Rf wedging group did not.

    I agree - best short term relief for plantar fasciitis - taping (supported by this and other studies)

    Yes - reverse Morton's (PMP 2-5); 1st ray cut out; kinetic wedge under 1st met head etc works well when incorporated in non-cast thermoplastic or OTC orthosis and makes up the majority of cost effective devices which I (and others) use. Included with other modalities as indicated

    Barry
     
  35. Lawrence Bevan

    Lawrence Bevan Active Member

    Barry

    My first name is Lawrence!
    I have found that on the whole, a casted soft EVA device with little posting also works well and makes up the majority of device I (and others) use for plantar heel pain. i would say there is also research to support this approach. I have found that a valgus wedge/2-5 forefoot extension can help but actually is not often needed and is rarely a deal-breaker. Ensuring the 1st ray in slightly plantarflexed in the cast seems to be adequate - at least for me.
     
  36. Bruce and Colleagues:

    Any varus wedged insole/orthosis that shifts the center of pressure (CoP) medially will tend to increase the medial compartment pressures and decrease the lateral compartment pressures of the knee. In addition, any valgus wedged insole/orthosis that shifts the CoP laterally will tend to increase the lateral compartment pressure and decrease the medial compartment pressure of the knee.

    To say that these in-shoe modifications will, respectively, cause medial compartment knee osteoarthritis (OA) or lateral compartment knee OA, is simply wrong since we simply don't know this from any existing research. However, with our current research and biomechanical modelling findings, clinicians should be aware of the fact that in patients with any level of narrowing of the medial or lateral joint cartilage at the knee, varus or valgus wedges under the foot can have a powerful effect at either increasing or decreasing medial or lateral compartmental pressures and should adjust their orthosis prescriptions accordingly.
     
  37. I believe that the only research that tells us that forefoot valgus wedges decreases the force through the medial plantar fascia is that by Kogler et al (Kogler, G.F., Veer, F.B., Solomonidis, S.E., and J.P. Paul: The influence of medial and lateral placement of orthotic wedges on loading of the plantar aponeurosis. JBJS (Am), 81(10): 1403-1413, 1999). Unfortunately this study used a static cadaver model without any Achilles tendon loading forces to more physiologically load the plantar fascia. Since we know that plantar fascia tensile force is very closely related to Achilles tendon tensile force from dynamic cadaver research (Erdimir A, Hamel AJ, Fauth AR, Piazza SJ, Sharkey NA: Dynamic loading of the plantar aponeurosis in walking. JBJS, 86A:546-552, 2004), then Kogler et al's 1999 study is significantly weakened, in my opinion, by 1) not loading the Achilles tendon and 2) being static. Therefore, I would be careful in using Kogler et al's reasearch to add valgus forefoot wedges to all patients with plantar fasciitis since, in my experience, there are a subset of patients who actually get worse with their plantar fasciitis symptoms with valgus forefoot wedges added to their orthoses. That being said, I do agree that slight forefoot valgus wedges do help many patients with plantar fasciitis and I have been using this forefoot valgus extension modification to my patient's orthoses on an occasional basis for the past 25 years.

    http://www.ncbi.nlm.nih.gov/pubmed/...nel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum
     
  38. efuller

    efuller MVP

    In my post, I left out how the windlass also creates a supination moment. Therefore, increased pronation moment from the ground can also increase tension in the fascia. A lateral forefoot wedge can decrease tension in the fascia by decreasing load under the 1st met and hallux, however it can increase tension by shifting the center of pressure laterally and increasing pronation moment from the ground.

    In some feet, non weigth bearing, if you pronate the STJ to end of ROM and hold it there, you can create a functional hallux limitus, through tension in the plantar fascia. (Functional in that there is more dorsiflexion of the 1st MPJ in a non pronated position than in the pronated position. In these feet, the fascia is tight to palpation when the hallux does not dorsiflex.)

    As I said above STJ pronation moments and 1st ray dorsiflexion moments are both theoretically related to tension in the plantar fascia. Sometimes breaking things down by planes (sagittal) helps and other times you do best in thinking about the whole foot 3 dimensionally. You can think of dorsiflexion moment on the 1st ray three dimensionally.

    In my own foot, which has a pretty bad functional hallux limitus, when I stand with my foot in a relaxed position there is more force under the medial forefoot than the lateral forefoot. (I learned a lot by playing with a force platform. ) I also have a very high amount of medial deviation of my STJ axis. Even though I have very little forefoot eversion, the orthotics that work best for me have a little bit of forefoot valgus intrinsic post. What I feel this does is decrease the load on the medial forefoot and increase the load on the lateral forefoot. However, I have over done this and created devices with too much valgus forefoot and caused sinus tarsi pain.

    So, in answer to your question, who should get forefoot valgus wedges: Those feet who you can slide your fiingers under the lateral forefoot really easily. That is they have very little force on their lateral column in stance. Others may benifit as well, but these are the ones that I'm sure should get it.

    Regards,

    Eric
     
  39. barry hawes

    barry hawes Active Member

    Hi Lawrence,

    My apologies re the slip up with your name. Ironic that you (as I) write under our own name and still a mug like me gets it wrong!

    I didn't really want to get into a detailed debate about the subtle differences that many of us have in the type of foot orthoses we prescribe for plantar fasciitis - I'm sure a range of different devices can be effectively applied. I just thought that Kahuna may have found the Bartold paper I mentioned an interesting clinical study applying the laboratory findings of Kogler et al.

    Cheers,

    Barry
     
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