Stan;
    Please let me know if I'm not contributing what you want exactly.  I've
been following this thread loosely at best.
    Determining whether a valgus or varus FF post or pad will increae the
midstance or propulsive phase is very difficult, and enigmatic at times.
You must understand that just because there is a prolonged midstance phase
in a foot that pronates longer, due to FnHL etc., that shortening the
midstance phase will not necessarily prolong the propulsive phase.  The
timing may indeed be very closely the same for propulsion, not always, but
often.
    I think that what Dr. Beekman my be getting at is that the valgus pad
should increase the pressure sub 1st mpj and as I've said before allow the
medial column to be more stable and provide for a more uniform pattern of
F/T curves from heel strike to toe off.
    In my opinion, the firing of the gastroc has little to no effect on the
outcome use in the example.  The gastrocs ability to fire has not changed,
only the foots ability to "roll" thru midstance in a uniform manner has been
changed.
    So long as the midstance period is "shortened" and more uniform, the MTJ
will need to compensate the AJ much less and therefore provide much more
intrinsic stablity to the foot for forward momentum.  This leads to a longer
hip extension and a later knee flexion, more closely tied to the 1st mpj
extension, and this will increase the stride length.
Sincerely;
Bruce Williams

-----------------------------------------------------------------
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
-----------------------------------------------------------------