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. Have you considered the Clinical Biomechanics Boot Camp Online, for taking it to the next level? See here for more.
    Dismiss Notice
Dismiss Notice
Have you considered the Clinical Biomechanics Boot Camp Online, for taking it to the next level? See here for more.
Dismiss Notice
Have you liked us on Facebook to get our updates? Please do. Click here for our Facebook page.
Dismiss Notice
Do you get the weekly newsletter that Podiatry Arena sends out to update everybody? If not, click here to organise this.

Advice plantar flexed first ray

Discussion in 'Biomechanics, Sports and Foot orthoses' started by ArnoLutin, Nov 2, 2017.

  1. ArnoLutin

    ArnoLutin Welcome New Poster


    Members do not see these Ads. Sign Up.
    Hi all
    Any advice on this. I'm confused.
    CC: W 30, burning pain only on CM1 and hallux, both sides.

    HPI: Pain is worse when playing racketsports. Leather (hard) orthotics with metabar(RCTB, 1-5), relief but after 60m of sports pain is back

    PMH: When not wearing orthotics: peronei tendinitis
    Sensitive to blisters (proximal to cm1, on the metabar)

    PE: //

    Musculoskeletal: mild pes cavus. Strong plantar flexed first ray. No forefoot valgus or varus. Normal ankle ROM. Stiff first ray (not much mobility to PF/DF) Rearfoot varus +3
    Normal MTP1 mobility. Palpation of fascia is painfull proximal to CM1.

    Gait examination: Out-toeing on the left. Slighty supinated gait pattern. Little bit of pronation during loading response. but both feet keep quit supinated. All CM's touch ground at the same time. Groundcontact of toes is late.

    No X-rays available.

    Cause:

    High loading on CM1/hallux because of the plantar flexed first ray and stiff first ray
    DD would be sesasmoiditis and flexor hallucis tendinitis

    Treatment Plan:
    A. Orthotic 40 shore forefoot with kinetic wedge 3mm.
    B. Orhotic 40 shore forefoot with RCTB (metabar) with kinetic wedge 3mm.
    But rcbt gives her blisters??
    C. Orthotic 40 shore forefoot with kinetic wedge 3mm but with forefoot correction???


    But my question:
    - What would the effect be (on MTP1) of a forefoot varus or valgus wedge (not a reversed morton extension) on a supinated gait with plantar flexed first ray?

    A forefoot varus wedge should increase the loading on MTP1 (and the pain) and fascia (witch is sensitive proximal to CM1) but in combination with kinetic wedge, this might work??

    A forefoot valgus wedge (not reversed morton extension) should unload MTP1 (if i think about plantar fasciitis)? but it also plantar flex the first ray? Do you want an already plantar flexed first ray to plantar flex more? Will that not increase the loading? But if i think about plantar fasciitis, it does reduce loading on MTP1..

    If there was a mobile forefoot valgus would u want to reduce first ray dorsiflexion and midtarsal joint supination? and how?

    I'm missing a few things in my reasoning but can't figure it out. Any advice where my reasoning is wrong or short?
     
  2. efuller

    efuller MVP

    CM1 = ? RCTB = ?


    A forefoot varus wedge seems like the wrong thing for an over supinator foot type. You need to understand why a foot is an oversupinator. Ground reaction force can cause pronation or supination depending on where the center of pressure is relative to the STJ axis. In over supinators the center of pressure is medial to the axis. A forefoot varus wedge will tend to shift the center of pressure more medial making the problem worse.

    You are getting confused by thinking about position and force. If you put a thick enough reverse morton's extension under a foot, even with a plantar flexed first ray, the ray could be maximally plantar flexed and have no force on it. It is ok for a plantar flexed first ray to be platnar flexed. It is not ok for there to be too much load on the first ray.

    It is important to understand why an over supinator foot will exhibit pronation. There is more than one source of pronation mment, or torque. Ground reactive force and muscular activity can cause pronation. In the oversupinator foot the ground is causing supination, but the muscles are causing pronation. When this happens, and there is adequate eversion available, the peroneal muscles will actually lift the lateral forefoot off of the floor and all the load will be under first met head and this is why you tend to see sesamoiditis in over supinator foot type.

    The above explanation ignores the axes of the midtarsal joint. Which is a good thing because there are no fixed axes of the MTJ. Specifically, there is no fixed longitudenal axis of the midtarsal joint around which the midtarsal joint could be supinated. Neutral position theory gets very confusing when they try to explain why a forefoot valgus or a plantar flexed first ray will exhibit pronation of the STJ in one foot and supination in another foot. This is why I like the tissue stress theory of foot function.
     
  3. ArnoLutin

    ArnoLutin Welcome New Poster

    RCTB= retrocapital bar (meta bar from 1-5)
    CM1: caput metatarsal 1 , should have said mtp1

    Thank you for the useful answer! I was indeed confusing position and loading and didn't see it. Thank you for clearing it out!
     
Loading...

Share This Page