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.

STJ effect on MTJ v MTJ effect on STJ

Discussion in 'Biomechanics, Sports and Foot orthoses' started by markjohconley, Aug 22, 2016.

  1. markjohconley

    markjohconley Well-Known Member


    Members do not see these Ads. Sign Up.
    Kinematically, does the STJ effect distal joints as much / the same / more than the MTJ effect proximal joints?
     
  2. efuller

    efuller MVP

    When?


    In static stance, equilibrium has been achieved at all the joints, so there would be little kinematic effect from one joint to another. This does point out one of the problems of neutral position theory. In neutral position theory there is an implied assumption that you start in neutral and then compensate for a deformity that is present. However, we should be looking at the position and forces acting on the foot when the pathology occurs and not some ideal position.

    Eric
     
  3. markjohconley

    markjohconley Well-Known Member

    thanks Eric, both statically and dynamically, weightbearing, does the relative position of the joints, effect the others. Wasn't thinking pathology wise, just functional anatomically.
    If we intervene with external forces at one which results in a change in position of the other (realising a change in net moments does not necessarily result in a change in position / motion) is that going to effect one 'way' more than the other?, mark
     
  4. efuller

    efuller MVP

    When the whole foot is on the ground a change in force will most likely affect all joints. You are asking a question with too many variables. As you try to increase force in one location it will reduce in another location (Total force has to equal body weight +/- vertical accelerations that occur with gait.) For some force changes the consequences would be easier to figure out and other locations it would be harder. Shifting the load more medially under the calcaneus is a pretty straight forward center of pressure calculation. What happens at other joints may still have too many variables to figure out what happens at other joints. Increasing the load on one metatarsal would be much more difficult to assess, because it would be harder to figure out where the load decreases.

    Too hard. Just make your changes and assess the results.

    Eric
     
  5. Agreed. At each instant in time you'd need to take moments about the instantaneous centres of rotation and know the load/ deformation in each of the tissues. Like Eric said- too hard.
     
Loading...

Share This Page