Anatomy of the thoracic vertebrae

The thoracic vertebrae are those vertebrae that are adjacent to the ribs surrounding the respiratory organs. There are eleven vertebrae with spines and wings and one vertebra without wings, for a total of twelve vertebrae. Their spines are not the same: those that are adjacent to the more important organs are larger and stronger. The wings of the thoracic vertebrae are harder than the others because the ribs connect to them. The top seven vertebrae have large spines and the wings are thick, so that the heart is sufficiently protected. Since the body of the vertebrae was used to form spines and wings, their articulating processes are made short and wide.

In the vertebrae located above, except for the tenth, the articulating processes directed upward have pits for the entry of the convexities of the lower processes, and in the processes directed downwards there are convexities that are located in the pits. The spines of these vertebrae are curved downward. As for the tenth vertebra, its spines stand straight, forming an arch, and the articulating processes have pits on both sides, but no convexities, since the articulating processes enter into them both above and below. Next come the vertebrae, which are below the tenth. Their bulges are directed upward, their pits are directed downward, and the teeth are curved upward. We will talk about the benefits of all this later.

The twelfth vertebra does not have wings, since, due to the presence of ribs, the force of the need for this is less. As for protection, a different method has been used for it, combining protection with another utility. Here is an explanation of this:  it turned out that it was necessary to give the lumbar vertebrae greater size and strength of articulations, because they bear on themselves what is located above. It is also necessary that

They had more pits and convexities, so their articulating processes were created double. However, the side of the twelfth vertebra adjacent to them should be similar to them, therefore its articulating processes are also created double. Thus, these processes consumed the substance suitable for use on the wings. Further, the twelfth vertebra was further expanded, so that its expanded part became like a wing and both utilities were immediately combined in this form. The twelfth vertebra is the one to which one end of the thoraco-abdominal septum is adjacent.

As for the vertebrae lying above this vertebra, due to their small size there is no need to strengthen them by increasing the number of articulating processes; however, they grow many spines and wings, so that the entire area of ​​their body is occupied.

Since the vertebrae of the chest are larger than the cervical vertebrae, their common openings are not equally distributed between the two vertebrae; on the contrary, their ratio gradually and little by little changes. In the overlying vertebrae there are more common holes, and in the underlying ones their number decreases, until finally the hole is located entirely in one vertebra.

As for the remaining dorsal vertebrae and lumbar vertebrae, the size of their body allows the entire opening to be located on it. The lumbar vertebrae have an opening on the right and an opening on the left for the exit of the nerve.