Stanley,
A basic search in google will reveal a wealth of information. Try a search
for "finite element foot", you'll get lots of hits including:
http://www.uni-essen.de/~qpd800/FW2001/LITPDF/asai4n.pdf
http://truegrid.com/gallery/show_foot.html
http://www.seattlerehabresearch.org/footmodeling.htm
http://asb-biomech.org/onlineabs/abstracts99/137/
etc. etc.................
Best wishes,
Simon
----- Original Message -----
From: "Dr. Stanley Beekman" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, December 15, 2004 6:03 AM
Subject: Re: EVA vs Plastic/Carbon Fibre FFO's: Discuss
> Kevin,
>
> Please excuse me, as it was 35 years ago that I took physics. Could you
> send me to an article, book, web page, or some other source that explains
> finite element modelling of the foot and lower extremity. I hope I am the
> only one on this list serve that is in the dark.
>
> Also please excuse my lack of physics knowledge, as I worked hard to get
my
> C. But I remember RXF as torque and the moment as the rotational weight. I
> am trying hard to put together what you are saying, and it doesn't seem to
> make sense. You say that since there is a very small positional change
with
> orthotics on the frontal plane, the motion of the joints doesn't matter as
> much as the moments that are changed with the orthotics. To change the
> moment, you have to change either R, or F. Since the force is constant
> (body weight), the only way to change R is by moving the part away from
the
> axis. Since little or no motion is occurring, then how do we change R?
>
> Craig found there is "no correlation between changes in the pattern of
> rearfoot motion and symptom reduction". This confirms that there is no
> change in rearfoot motion, so therefore there is no change in R.
>
> Can you explain this contradiction to me?
>
>
> Respectfully,
>
> Stanley
>
>
>
>
> At 07:09 PM 12/14/04 -0800, you wrote:
> >Bruce and Colleagues:
> >
> >Kevin wrote:
> >
> ><<5. Scientific studies that only measure the kinematics of gait are
> >basically useless in showing the mechanical effects of foot orthoses
since
> >they do not measure the forces and moments acting across the STJ,
> >midtarsal joint, ankle joint and other joints of the foot during
> >gait. Only kinetic studies of the foot and lower extremity and/or finite
> >element modelling of the foot and lower extremity will be able to show
the
> >mechanical and therapeutic effects of foot orthoses. Many of these
> >kinetic studies and finite element modelling studies have already clearly
> >shown the mechanical effects of foot orthoses on the human foot.>>
> >
> >Bruce replied:
> >
> ><<I can't agree with this statement. I think that it would be more
> >correct that say that kinematic studies focusing on calcaneal motion, or
> >lack therof, are basically useless. I think it may be possible to glean
> >much more useful information by focusing on other parts or joints in the
> >foot and ankle. Much like Drs. Nester, Cocheba and Ward have done. I
> >certainly don't feel that their research to date has been "basically
> >useless".>>
> >
> >Kevin replies:
> >
> >Thanks for taking the time to disagree with me, Bruce. My statement
above
> >would better reflect my current thoughts on the subject if it read as
> >follows: "Scientific studies that only measure the kinematics of gait in
> >live human subjects show little promise in helping us determine the
> >mechanical effects of foot orthoses since they only measure motion and do
> >not measure the forces and moments acting across the STJ, midtarsal
joint,
> >ankle joint and other joints of the foot during gait."
> >
> >For you to suggest that I think the research of Drs. Ward, Nester,
Cocheba
> >and colleagues is useless is a little bit off base, Bruce. For one
thing,
> >their research was on cadaver specimens without foot orthoses being used
> >so that their research did not even address the question of foot
> >orthoses. In addition, their research is not a pure kinematics type of
> >research since they do have control over the force input into each of the
> >muscle tendons during the walking cycle which allows a force quantity to
> >be modified.
> >
> >Because of their ability to control tendon tension input this makes their
> >research not purely kinematic since it has a large potential to gather
> >useful kinetic data by relating muscle tendon force input to observed
> >kinematic patterns. This type of research on their machine with cadaver
> >specimens could certainly be used with cadavers "walking" both with and
> >without foot orthoses to determine how foot orthoses may change the
> >tensile loading forces in the extrinsic muscles of the foot since they
> >would have access to the kinetic function of the muscle tendons in their
> >experimental model.
> >
> >Kinetics and finite element modelling, this is where the "pay dirt" will
> >be in understanding how foot orthoses truly do work.
> >
> >Cheers,
> >
> >Kevin
> >
>
>***************************************************************************
*
> >Kevin A. Kirby, DPM
> >Adjunct Associate Professor
> >Department of Applied Biomechanics
> >California School of Podiatric Medicine at Samuel Merritt College
> >
> >Private Practice:
> >107 Scripps Drive, Suite 200
> >Sacramento, CA 95825 USA
> >
> >Voice: (916) 925-8111 Fax: (916) 925-8136
>
>***************************************************************************
*
> >
> >
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