Re: Hip-knee-ankle joints on 1 line (Re: A.afarensis:samedietthrough time & in diverse paleo-ecol.conditions

Marc Verhaegen wrote:

Op 17-12-2007 07:33, in artikel 47661825.7EFE0916@xxxxxxxxxxxxxxx, Rich
Travsky <traRvEsky@xxxxxxxxxxxxxxx> schreef:

A vertical posture is 20 Ma, see A.Filler (the Moroto lumbar vertebra has
a
very dorsal transverse process).

More specific (you never know what savanna believers misunderstand...):
vertical spine.

The point here is: hip+knee+ankle=1line in humans standing on 2 legs,
whether the legs are under the pelvis or not.

Every doctor has learned that in his anatomy classes.
It makes the leg more stable in standing.

More specific (you never know what savanna believers misunderstand...):
- If 1 leg supports our weight, the hip+knee+ankle joints of that leg are on
1 line. That leg is then perpendicular under our centre of gravity, of
course, and the tibia of that leg has then its shaft vertical (but not the
shaft of the femur, of course!).

- If 2 legs support our weight, both legs have their joints on 1 line,
whether the feet are under the pelvis or not. Our centre of gravity is then
perpendicular above the middle of the line between our 2 feet, of course.

Got it a bit??
If not (as I suspect), draw it.
And think a little bit.

The same was presumably true for standing apiths as well.

It implies (trigoniometry) that if you know
1) the angle between femoral neck & shaft,
2) the length of the fem.neck,
3) the length of the shaft between fem.neck & knee,
you can deduce the valgus angle (because the tibia shaft is on 1 line with
the hip joint).

Draw it. It's easier than savanna believers can imagine.
It has nothing to do with placing tibias perpendicular or so.

Examine figure 1a in
http://starlab.stanford.edu/pdfs/BichondAngle=Bone2002.pdf
Take a lath: hip+knee+ankle = 1 line.
Okidoki?

I hope you know the difference between the joints & the shafts??
(You never know with savanna believers... :-D)

If it was a straight line there'd be no bicondylar angle, Marc...

yes, that's what I'm saying. You're stupid & will remain stupid, I don't
think you'll ever learn German. Start with the umlauts.
If we know
1) the angle between femoral neck & shaft,
2) the length of the fem.neck,
3) the length of the shaft between fem.neck & knee,
we can deduce the valgus angle (because the tibia shaft is on 1 line with
the hip joint).
Draw it.
It's easier than you think.
It has nothing to do with placing tibias perpendicular or so.
Examine figure 1a in
http://starlab.stanford.edu/pdfs/BichondAngle=Bone2002.pdf
Take a lath: hip+knee+ankle = 1 line.

With a non zero angle.

Me - If it was a straight line there'd be no bicondylar angle
You - yes, that's what I'm saying

You do not appear to know what lines and angles are.
.

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