Spine: A curved lesson

[bernard]

Hello All,

I created this thread to show how human body plays with gravitation.
Our spine is a marvel and very flexible but elastic at once.
Its function is not in carrying huge loads but it absorbs them and transmits the forces to the ground.

Here is a little animation that shows 3 perspectives:
A straight spine (doesn't exist).
A flexible one (lumbar)
A more flexible one (cervical).It is a very simplified view but may bring some questions about it?

http://www.somasimple.com/flash_anims/scurve2.swf


Click on the PLAY button.

[bernard]

If we omit the vertical motion and place the origins of forces at the same level, it is possible to see, firstly, the horizontal forces created with the flexible mediums. But the miracle happens later...

http://www.somasimple.com/flash_anims/scurve3.swf

Click on the PLAY button.

[bernard]

Then it is more interesting to look at, in a closer manner, the vertical components of these forces.

If we were able to add an horizontal "vector" because we changed the direction of the applied gravitational "fate", it seems normal to think that something happened there and that it may be useful for our "weak" spine.

http://www.somasimple.com/flash_anims/scurve4.swf

[Diane]

These are cool images Bernard..
With respect to the nervous system, I wonder if there is a way to depict the fact that the forces are operating on a system that is fixed at both "ends"..?

[bernard]

I wonder if there is a way to depict the fact that the forces are operating on a system that is fixed at both "ends"..?
Perhaps these old trials need some refinement:

http://www.somasimple.com/flash_anims/slider.swf
http://www.somasimple.com/flash_anims/slider02.swf

[bernard]

So, the first conclusion that may give a flexible and elastic spine is this one :

A straight segment transmits very well forces and loads.
A flexible absorbs them, changing hard rules and "plays" with gravitation.

[bernard]

It becomes also understandable that three curves act better than a single one but only if the load is applied on the top of the "heap".

It explains why the brain is still there: It is the best place.