Dear all

my ears have been burning! Sorry for slow reply.

Bruce did get the conclusions I presented recently at the Western
conference correct, and we termed the "functional" articulations of
the proximal, distal and lateral tarsal joints. For the moment we are
working with these concepts, but the same project has produced a
good deal of other data and we are currently processing this. I have
just returned from a meeting with our researcher who is
systematically combining the different bones of the foot, using the
rigid segment assumption, and then seeing how a particular
combination of bones affects the kinematic description we get from
experiments, and of we course use in clinical and mailbase
dialogue. So, for example, if in experiments we put markers on the
first and fifth metatarsal and use this to describe "forefoot" motion,
how well does it actually represent the movement of the
metatarsals relative to say the cunieforms or cuboid. Likewise can
we discuss such a thing as the "forefoot " segment as if it is a rigid
entity?

This work is far from complete and is likely to produce a more
complete picture of exactly which bones can and cannot be
combined in a rigid segment model. I would be more confident in
stating exactly what we should be talking about in terms of clinical
and experimental models of the foot and ankle once this latter work
is complete. However, based on the work to date and observations
of the data I stick by the proximal, distal and lateral tarsal joints.

Kevin is quite right that there are issues with the cadaver simulator
and how well it replicates gait/stance. The lack of intrinsics and
active control of frontal and transverse tibial motion are key factors I
believe and are on the drawing board for future additions/versions of
the simulator. However, it is interesting to see the videos and how
well the foot "walks" without these elements. The replication is not
a million miles from real gait, though, certainly, I would have greater
confidence in the results if additional elements were controlled.

However, the use of our data and its place in these discussions
might also depend upon a persons perspective. If the data is
viewed on the basis that we already have a perfectly sound clinical
model of the foot and ankle for the moment and that really quite
clever data presenting a very complete answer to exactly how the
foot works must appear before we throw away the existing model,
then this data might sit on the shelf (wrongly). Alternatively, you
could see our existing knowledge, particularly of the articulations
distal to the navicular and cuboid as being in effect non existant in
terms of actual data, then our data  is perhaps the only believable
information we have, to date. I sit in the latter camp, and really feel
the foot is still a relatively blank piece of paper. This does not of
course mean that the data we have collected is without its
limitations, it certainly is, but when it is data versus no data, I 'd go
for the reasonable data we have everytime. Also, I would do this
understanidng fully that in years to come what I and other write and
say will be superceded by our own future work, and that of others,
and that that is fine by me. "When the paper is blank, there is
plenty room for writing, and we should at least pick up the
pen........... "

Best wishes
chris








Dr Christopher Nester  BSc PhD
Senior Research Fellow
Brian Blatchford Building
School of Health Care Professions
Centre for Rehabilitation and Human Performance Research
University of Salford
Salford
M6 6PU
England
http://www.healthcare.salford.ac.uk/crhpr/
http://www.realprof.eu.com
TEL:0161 295 2275
FAX:0161 295 2668

-----------------------------------------------------------------
This message was distributed by the Podiatry JISCmail list server

All opinions and assertions contained in this message are those of
the original author. The listowner(s) and the JISCmail service take
no responsibility for the content.

to leave the Podiatry email list send a message containing the text
leave podiatry
to [log in to unmask]

Please visit http://www.jiscmail.ac.uk for any further information
-----------------------------------------------------------------