Welcome to the Podiatry Arena forums

You are currently viewing our podiatry forum as a guest which gives you limited access to view all podiatry discussions and access our other features. By joining our free global community of Podiatrists and other interested foot health care professionals you will have access to post podiatry topics (answer and ask questions), communicate privately with other members, upload content, view attachments, receive a weekly email update of new discussions, access other special features. Registered users do not get displayed the advertisements in posted messages. Registration is fast, simple and absolutely free so please, join our global Podiatry community today!

  1. Its been a busy week moving to new domain and new server and new platform. We still have a lot to do. The basic functionality is there, but we working long hours on the rest and awaiting the new design.
    Dismiss Notice

Plantar fasciitis/osis

Discussion in 'Biomechanics, Sports and Foot orthoses' started by bob, Mar 12, 2012.

  1. bob

    bob Well-Known Member


    Members do not see these Ads. Sign Up.
    Please can someone with a more complete knowledge of biomechanics help me to understand why orthotics with medial arch support are beneficial for patients with heel pain? My basic understanding of plantar fasciitis is that tension in the plantar fascia as the patient weightbears is responsible for pain at the origin/ enthesis. If I put an insole with arch filler into this type of foot, does this not increase the tension/ traction on the plantar fascia? The shortest distance between 2 points is a straight line. If I can make that straight line shorter, I should reduce tension in it? If I put a big bend in it by shoving an arch support in there it increases the distance right? Please can someone help me out with this as I feel a fraud when I am trying to explain to patients why they might benefit from an orthotic. Thanks.
     
  2. mike weber

    mike weber Well-Known Member

    Bob in this thread I posted some studies which might help.

    http://www.podiatry-arena.com/podiatry-forum/showthread.php?t=70176

    I was explaining this to a some physios the other day

    think of the foot as an A frame ladder

    where the A is the arch with the - as the tension band or plantar fascia

    pull the legs out and we get greater tension in the tension band

    push up under the tension band the feet of the ladder come in and we get reduced tension

    but the key is to think in terms of dynamic function and timing - so yes even with an orthotic or arch fill we will get increased tension but if the timing of the tension is different or reduced in time - potentially less pain.

    also the arch fill will not just have one effect - in one word - windlass

    there is some papers there in that thread - also have you read Eric paper

    J Am Podiatr Med Assoc. 2000 Jan;90(1):35-46.
    The windlass mechanism of the foot. A mechanical model to explain pathology.
    Fuller EA.


    Abstract
    This article presents a mechanical model that can be used to understand the foot, to help develop methods of treatment of foot pathology, and to provide direction for future research in foot mechanics and pathology. The anatomy and mechanical function of the windlass mechanism of the foot are analyzed using principles of mechanical engineering. The principles of force couples and free-body diagrams are explained and then applied to the foot. The relationship of the windlass mechanism to plantar fasciitis or heel spur syndrome, hallux abducto valgus, and hallux limitus is discussed.

    hope that helps

    if you can´t get a full copy shoot me off your email address in a pm and I will send you a copy.
     
  3. musmed

    musmed Well-Known Member

    Dear All
    Are you trying to say the higher the bell curve the less the surface area under it??

    I do not understand your logic. The ladder idea
    in closing the ladder the two parts (steps) are coming closer together, I do not see the toes coming closer to the heel enough to change the tension.

    The reason why this mid foot lift works is because it off loads the medial-lateral cunieform joint which is in my book the most common cause of heel pain.
    Another reasonwhy it works is because it produces accupressure to the abd hall trigger point which is in about 60% of all heel pain.

    The plantar fascia is grossly overrated. Where it finishes in the fat of the toes it is so thin it is impossible to see on MRI and after all it is called the foot fascia.
    it is no different to the palmar fascia. This does not get into trouble. I have never seen a weight lifter with a palmar fascia injury, has anyone out there?
    Like the palmar fascia the plantar fascia just separates the foot fat from the other structures and thus allows the interaction of the pressure receptors and th shape of the bones (rounded) to perform their Gaussian mathematics and produce the bell shaped distribution of pressures around bone and thus allow us to maintain the forces needed in the hand to hold something without dropping it and in the foot from slipping.

    Regards
    Paul Conneely
     
  4. mike weber

    mike weber Well-Known Member

    Paul go read the articles I suggested by linking to another thread in my 1st post.
     
  5. Rob Kidd

    Rob Kidd Well-Known Member

    I think one of the key issues in "so-called" plantarfascitis is that one is not looking at straight lines, so to speak, one is looking at abnormal angle of pull relationships. By way of example, take any foot and pronate it - or, probably, supinate it, the origin-insertion relationship of the plantarfascia - and its critical Sharpies' fibres, are no longer aligned optimally; they will thus fail prematurely. Thus, as I see it, therapeutics are aimed at re-aligning the origin-insertion relationship. This, at least to some extent, explains why it is that alterinhg the forefoot-hindfoot relationship in either direction may be found to be beneficial to a heel-pain sufferer - one is simply inflicting a new and different stress situation. Although this phrase is normallly used in the statistical sense, in this case one could also use it in the geometric sense: "there are no straight lines in biology".............Rob
     
  6. CraigT

    CraigT Well-Known Member

    Hi Paul
    I find your techniques and approaches very interesting and I have seen they are effective.
    One quick question-
    How many of your patients see you as their first 'port of call' for their foot pain??
    I agree that abductor hall is a common culprit in 'plantar fasciosis', but I think the 60% figure you saw may be a bit skewed- perhaps because you see a higher proportion of recalcitrant cases???
     
  7. bartypb

    bartypb Well-Known Member

    In all honesty I rarely use insoles as I have found that generally they don't really help, strapping and stretches to gastrosoleus have a much better outcome no one has been able to explain to me why this is? That is just a personal observation and I have no data to back it up.
     
  8. RobinP

    RobinP Well-Known Member

    Bob,

    I won't pretend to have a clue what Paul is talking about as it is totally beyond my comprehension but I would not think to much about the actual arch support pushing into the fascia. If someone has a plantar fascia that is injured because it is absorbing a load that is too great , there are many different ways of reducing the plantar fascia tension, one of which is providing an arch support

    Without pushing into the arch of the foot, I can reduce tension in the plantar fascia (which will be shown by a decrease in the dorsiflexion stiffness at the 1st MPJ in weight bearing). A simple example would be a medial heel wedge or a lateral forefoot wedge. Neither will directly push into the arch but will alter the centre of pressure to reduce the load on the 1st MPJ which usually will improve Windlass function

    The reality is that the method by which you reduce the tension in the plantar fascia is irrelevant. Reducing it will largely relieve the pain. I definitely think that the diagnosis of the fasciosis needs to be accurate as I believe also that there is a large amount of misdiagnosis when really it is abductor hallucis/tarsal tunnel syndrome/plantar ligament sprain etc etc
     
  9. musmed

    musmed Well-Known Member

    Dear Craig
    Hi and thanks for the good question.

    I asked my data base this question and it rated 60% had been St. Elsewheres and 40% I was the first base.

    The figure of 60% is similar to those who use the shock wave therapy. In Perth last year they were demonstrating these machines and a doctor gave a 20 minute talk and demonstration
    Interesting enough they were placing the shock wave probe on the abductor hall not the PF.

    Most people including podiatrists (as seen in workshops) do not realise that the calcaneum is markedly lateral in respect to the heel as a whole.

    Trust you are not frying over there. we have had more rain here in 3 weeks than 2 years on average
    Regards
    Paul Conneely
     
  10. The reason for heel pain / Plantar Fasciitis is due to tension on the orgin an insertion of the fascia / tendon. This tension is cause by fallen arches / Flat arches or over pronation. By lifting the arch and fascia, this acutally takes tension off of the orgin and insertion of the tendon.

    In this case the shortest distance between two points does not apply because it's not about distance it's about getting the arch and Fascia back to an anatomical postion so it's not pulling on the Tendon. The Fascia is already in it's anatomicaly correct postion when the arch is up where it's suppose to be with no tension. When the arch drops or pronates it now pushes down on the fascia causing it to pull from the orgin and insertion.

    Besides.... returning the arch to it's biomechanically correct positon for treatment with orthotics.....it's the Gold standard for podiatrists and physical Therapists across world.
     
  11. Craig Payne

    Craig Payne Moderator

    ....not even close to be true!
     
  12. RobinP

    RobinP Well-Known Member

    Brian, are you a podiatrist? When you say tendon, are you talking about the fascia?

    -In a population of runners of African origin, how many do you think will have "fallen arches/flat feet or over pronation"?
    - Is their their plantar fascia in an anatomically incorrect position?
    - How many track athletes of African origin will be competing at the 2012 Olympics this year?
    -DO you think that most of them will have fascia problems as a result of their arch dropping down and pushing on the fascia?

    Regards,

    Robin
     
  13. dragon_v723

    dragon_v723 Well-Known Member

    interesting Rob sounds like u have an article re the African any link?
     
  14. RobinP

    RobinP Well-Known Member

    I don't. I was making the point that, as an ethnic group, people of African origin tend to have lower arched feet/pronated feet than would be considered "normal" by anyone who believes in vertical heels and sub talar joint"neutral"

    By definition, that would make them abnormal. I could make the same point with caucasions, (or any group of people for that matter) only that the percentage of track athletes of African origin is (probabaly)greater and it is topical
     
  15. dragon_v723

    dragon_v723 Well-Known Member

    nice observation

    but what is ur approach to ppl with real complaint and lower arched feet/pronated feet? would u still put the stj back to 'neutral' or?
     
  16. toomoon

    toomoon Well-Known Member

     
Loading...

Share This Page