Trevor:
In a message dated 9/4/98 11:11:20 AM Pacific Daylight Time, [log in to unmask]
writes:
<< This statement seems to say that in some feet the forefoot effects the
rearfoot and vice versa. When I suggested that fhl may be caused by rearfoot
pronation and vice versa you used an analogy of an egg breaking on the
ground.
You now appear to agree that motion (or moments etc.) can work either way. >>
All I was saying is that just because motion A causes motion B in any system,
the opposite does not necessarily hold true than motion B causes motion A. My
analogy of the dropping of an egg onto the ground (motion A) causes a breaking
of the shell (motion B) does not mean that breaking of the shell (motion B)
will cause dropping of the egg (motion A). This was in response to your
previous statement from the date of 8/24/98 in which you said "I believe that
if one motion can cause the other, the reverse is also possible."
This certainly does not mean that in some instances that motion A can cause
motion B and motion B can cause motion A. However, in many instances, motion
A may cause motion B, but motion B couldn't cause motion A to occur.
Therefore, if you agree with my analysis, your statement that "if one motion
can cause the other, the reverse is also possible" would be false.
My point in belaboring this argument is that just because STJ pronation can
cause FHL, that there is any method for FHL to cause STJ pronation. If you do
have a proposal as to why FHL causes STJ pronation, then I am very anxious to
hear it. As I said much earlier in this discussion, I feel this is one of the
weakest areas of Howard's sagittal plane theory.
Trevor, enjoy your vacation. I am enjoying the chance to discuss these
subjects with you.
Cheers,
Kevin
*****************************************************************************
Kevin A. Kirby, D.P.M.
Assistant Clinical Professor of Biomechanics
California College of Podiatric Medicine
Private Practice:
2626 N Street
Sacramento, CA 95816
Voice: (916) 456-4768 Fax: (916) 451-6014
*****************************************************************************
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|