🥇 COLUMNA VERTEBRAL 1/5 - Generalidades, Curvaturas. Fácil y Sencillo

good good my dear students of anatomy, my name is juan josé sánchez and today we will talk about the vertebral column or what the spinal column is, before starting I urge you, I invite you to join my channel here in the corner At the bottom right I leave you a link so you can directly subscribe to the channel, so the vertebral column is a very long structure to study in anatomy, that is why I decided to divide the content into several videos, today we will talk about the generalities of the column, as well as its curvatures, so the vertebral column is the column of the body, it is what makes us able to stand up, we can stand, since it is a support structure, of rigid support, but at the same time It is quite flexible, which is what carries the weight of our entire body and then transmits it to the lower limbs. In addition, it has a very important function, which is that inside the spinal column there is a channel that is the medullary canal. where the spinal cord passes, so that it also serves to protect that important structure of the nervous system such as the spinal cord, then that vertebral column is made up of a set of bones that we are going to call vertebrae, each bone we are going to called a vertebra, it originates at the base of the skull ok and ends at the tip of the coccygeal bone, then the first vertebrae that we are going to see are 24 vertebrae, which are what we call presacral vertebrae, because they are before the great sacral bone that It is this one that you see here, however the sacrum bone is also considered a bone of the vertebral column, as well as the bone that comes after it, which is the coccygeal bone, but mainly we are going to see that what anatomy places the most emphasis on the presacral vertebrae, they come in several groups according to their location and according to the anatomical structures of each group, then the 24 presacral vertebrae, we divide them into three groups, the most superior group which is the one that corresponds to the neck that It is what we are going to call cervical vertebrae, which are seven and what is common in most people is that they have seven cervical vertebrae and they are denoted in anatomy with the letter c, the most superior being the first, they are always counted from the top downwards , then the one that is attached to the base of the skull is c1, then c2, c3, c4 until c7, it is the one that is in the part of the neck that is why they are called cervical vertebrae and never forget it which are 7, then come 12 thoracic vertebrae ok, those thoracic vertebrae are also found in many books under the name of dorsal vertebrae, it is the same, they are 12, they also begin to be counted from top to bottom, after c7, then comes d1, d2, d3, up to d12, as they are also called thoracic vertebrae, you can also find it in some texts with the name of t1, t2, t3, up to t12, likewise and then to finish the 24, we already have 19, there are five Lumbar vertebrae, which are the last of the presacral vertebrae, which is the one that will later continue with the sacral bone, the lumbar vertebrae are also five, they are denoted with the letter l, which is l1, l2, l3, l4 and l5.

The large bone that you see here complete is called the sacral bone, which is nothing more than the fusion of five vertebrae, only in anatomy it is studied as a single large vertebra, which is the sacrum bone, and finally the coccygeal bone, which is nothing more than the fusion. also of four vertebrae, the sacrum is five and the coccyx or coccygeal bone, the names vary in anatomy, it is the fusion of four vertebrae, so that these are the bones that make up the vertebral column and which in the following video I will explain the characteristics of the cervical vertebrae, how they differ from the thoracic vertebrae and what differentiates these two from the lumbar vertebrae because each one has specific characteristics and that is why this classification of the presacral vertebrae was made , So that vertebral column in length measures two-fifths of the total body height ok, those presacral bones are articulated with each other and separated by these structures that we will see later in a video of spinal joints that It is what we call intervertebral discs, because they are discs that are between the vertebrae, they are sheets or cartilaginous discs, which is what helps it to have that arch shape, so that it can have that great flexibility, so it is said to have an arch shape. conical, that is, from the cervical vertebrae to the lumbar vertebrae because as it descends it becomes wider and higher.

This is because as the spine descends, it obviously has to support more weight. That is why the vertebra that is below the one preceding it is always thicker and higher, because it has to support more and more weight because more and more structure is added to it until it reaches the lumbar vertebra, which is the widest of all and the highest of the entire lumbar spine, because it is the last of the presacrals, and then that cone begins to invert with the sacral bone, coccygeal bone because they are structures that no longer carry almost any weight because already at the level of The upper part of the sacrum is that the weight is transmitted from the entire body to what is the coxal bone and the coxal bone of the hip to what are the lower limbs through the femur, so do not forget this conical shape and a very important angle that we study a lot in traumatology, which is an angle that forms a line that we are going to pass through the entire axis of the lumbar vertebrae and the entire axis of the sacral bone, that angle is going to be called the lumbosacral angle and the normal thing is that measure from 130 to 160 degrees, it should not even measure less than 130 or more than 160 because we say that there is already a pathology at the level of the lumbosacral angle, now see that the spine seen from a lateral view, I remind you that It is anterior, this is posterior and what we are seeing is a left lateral view specifically, then, seen from the side we see that it is no longer completely straight but rather has a curvature, that is important for its function because as I say it already serves as the bow with the wooden part of a bow that you can press and it is like a spring thanks to this curvature it can already be its damping function, so see that we are going to go to these curvatures in two large groups, be careful, they are curvatures that we see from an anteroposterior sense, processes that are also called anterosuperior curvatures, then we will first have the great primary curvature, these primary curvatures are specifically the curvature of the dorsal column and the curvature of the sacral column, they have the characteristic The primaries are always concave forward, see that previously they show a concavity but it is not wrong to say that they are also convex backward, because everything that is concave forward is also convex backward, or at least in this case Anatomy, it is like seeing a spoon has a concavity but seeing it from behind and it is a convexity, then it is said that the primary curvatures that are the dorsal and the sacral are concave forward or what is the same as saying convex towards back, towards posterior, because they are called primary curvatures they are called primary curvatures because they follow the same axis of the curvature that the embryo has, you see an embryo embryology it is the entire spine is concave forward, the entire column then these curvature as follows Already in adult life, the same forward concave shape is said to be primary, because the same embryonic curvature follows the same line and is formed in the embryonic stage. Then, we will talk about the secondary curvatures, which are the second group of curvatures in the sense posterior antrum, those secondary curvatures are the curvature, so those that are left over, cervical and lumbar, see that they are interspersed, a secondary cervical, a primary thoracic, a secondary lumbar and a primary sacral, those secondary curvatures are the opposite, see that they Rather, they are concave towards the back but towards the front they show me the convexity, so the same thing I would say is that they are concave towards the posterior but convex towards the anterior, so you already know that they are already interspersed so that they can counteract each other and function as a spring, these two are the groups of anteroposterior curvature structures, now because these Curvatures are called secondary, he explained to them when we are born these curvatures are all concave forward, they are primary, because they are those of the embryo, but as the child after he is born and raises his head they begin to form in the embryonic stage but they end to form after the child is born, when he manages to raise his head, which is upright, this backward curvature is formed because the weight on the head causes the cervical curvature to form and the cervical curvature is formed, while the curvature The lumbar spine is formed when the child can stand up, which stabilizes, so that is why these two are called, the cervical and the lumbar secondary curvatures and that is why they are with the head backwards, so how are these curvatures formed?