In a uniform system the contraction of the digitations from the diaphragm to the bisector is accompanied by resistance of the anatomical pillars from their centre.
The image on the left shows that to have a uniform deployment of the thorax you need two inverted umbrellas with the sliders that open them. Contrary to the mobility of the umbrella's slider in
the center that raises the ribs, the mobility of the sliders gives us a fixed center for the pillars.
This centre fixation should attract attention in the frontal plane because the pillars are not at the same height. This implies a compensatory adjustment at the level of the central nervous
system.
Contraction of the diaphragm with negative intercostal resistance above the diaphragm + positive abdominal resistance below the diaphragm at inspiration. If the phrenic centre is fixed by an intra thoracic and intra abdominal centre, the mobility of the above and sub-diaphragmatic sliders is reversed in the same breathing time. And it is the same on expiration. This opposes the notion of a generalized piston diaphragm in medicine.
Si toutes les cotes montent dans les plans antérieurs et postérieurs, en montant elles ont écarté les deux hémithorax en écartant les centres bronchiques.
En montant dans le plan frontal antéro-postérieur au lieu de se déployer, les cotes sont montées aussi dans le plan sagittal au lieu de se déployer.
A l'expiration les intercostaux n'étant pas ouvert a l'inspiration dans les deux plans ne peuvent pas se contacter pour reployer le thorax. Les cotes étant montées ne peuvent
que descendre. Mais l'écartement des centres bronchiques dans le plan frontal va amener les cotes a descendre dans le plan sagittal en rapprochant les plans antéro- postérieurs
des centres bronchiques. A condition que la montée des cotes dans les plans antéro-postérieurs soit symétrique. Dans le cas contraire la descente des cotes sera asymétrique.
I represent on the left the opening of the umbrella with a rise on all sides. The thorax widens but the intercostals do not open in the third dimension. They diverge in the frontal plane.
But for a thorax that expands to the right you see that there is dysfunction. The slider goes up with the first ribs but the slider that lowers the last ribs is missing. With the thorax on the
right I open the intercostals from the center of the thorax in three dimensions.
What you have to understand is that if the ribs go up in a plane instead of opening, the intercostals don't open. On exhalation it will be impossible for them to close the thorax.
It's like asking the biceps to bend a closed elbow.
If all the ribs rise in the anterior and posterior planes, by rising they have spread the two hemithoraxes by spreading out the bronchial centres.
By ascending in the anterior-posterior frontal plane instead of unfolding, the ribs are also ascending in the sagittal plane instead of unfolding.
At expiration the intercostals not being open to inspiration in both planes cannot contact each other to fold the thorax. As the ribs are raised, they can only descend. But the distance between
the bronchial centres in the frontal plane will bring the ribs to descend in the sagittal plane by bringing the antero-posterior planes closer to the bronchial centres. Provided that the rise of
the ribs in the antero-posterior planes is symmetrical. Otherwise the descent of the sides will be asymmetrical.
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