The vertebral column or spine, located in the dorsal part of the torso, is an osteoarticular structure , made up of a stack or chain of articulated bones called vertebrae. It has the main function of supporting the trunk and the orientation of the head whatever the position of the body.


What is the spine?

The spine is the main supporting structure of the human skeleton . It is composed of separate, semi-separate or welded vertebrae . Likewise, the spinal column is made up of numerous joints that allow the support and mobility of the skull and the flexion of the neck and back. In addition, this structure that begins at the base of the skull and extends to the pelvis, supports and protects the spinal cord .

  • General characteristics of the spine
  • Function
  • Types of vertebrae
  • Parties
  • Structure of the spine
  • Joints
  • Spinal bones
  • Curvatures
  • Injuries and diseases associated with the spine
  • Importance

General characteristics of the spine

  • Four prominences that articulate with the neighboring vertebrae.
  • Cylinder-shaped bone mass in the front.
  • Two lateral processes called the articular processes.
  • The pedicles that constitute lateral walls of the medullary canal and that unite the body with the rest of the vertebra.


It could be said that the spinal column has four main functions:

  • Hold the trunk upright . The spine has natural curvatures that intervene in the balance and stability of the back.
  • Articulate the movements of the trunk . The spine gives stability and posture to our body. It is made up of bones stacked between them that are articulated by means of invertebrate joints and ligaments.
  • Unite the muscles and internal organs .
  • Protect the spinal cord in its entirety. In the spinal cord, the different nerve endings responsible for sensation and motor skills of all parts of the body branch.

Types of vertebrae

The spinal column is made up of approximately 33 vertebrae that overlap and articulate with each other. Next, the different types of vertebrae are distinguished:

  • cervical vertebrae , located in the neck.
  • 12 vertebrae torah cycads , located in the region of the chest.
  • lumbar vertebrae , located below the last thoracic bone and above the sacrum.
  • From 3 to 5 vertebrae welded to the coccyx .


The vertebrae of the spinal column are positioned in such a way that their vertebral canals form an empty bone tube that fulfills the function of protecting the spinal cord from external and infectious agents. The channels make it possible for the spinal nerves to leave the spinal cord and connect with the different regions of the body.

  • Cervical region: it is made up of the 7 vertebrae located in the neck . It is thus about cervical vertebrae that have the characteristic of being more final and fragile. These give the neck great flexibility.
  • Thoracic region: it is made up of 12 vertebrae located in the chest area . They are larger and more robust vertebrae than those located in the cervical region but have less flexibility. These protect the organs of the chest.
  • Lumbar region: it is made up of the 5 vertebrae located in the lumbar region , even larger and more robust than the thoracic region. Also, this area has greater flexibility since there are no nerves. It is on this region that the upper part of the body rests.
  • Sacral region : This region only has one bone when it reaches adulthood . It is a bone made up of 5 smaller vertebrae that fuse in adolescence . Its shape is flat and triangular and is located in the lower part between the two hip bones .
  • Coccygeal region: in this region is the human coccyx formed by the fusion of four small vertebrae in the adolescent period . When we sit down, this bone supports the weight of the body. Also, this constitutes a point that joins the muscles of the buttocks and the pelvic region.

Structure of the spine

The spinal column is made up of:

  • An armor : bone structure, joints, ligaments;
  • Paravertebral muscles that ensure support and mobility;
  • Nerves that ensure motor and sensitivity responses.

The vertebral column constitutes a stack of 26 vertebrae (33 if the welded vertebrae of the sacrum and coccyx are counted). They are distinguished as follows from top to bottom:

  • 7 cervical vertebrae, the cervical spine ;
  • 12 thoracic vertebrae, the thoracic spine ;
  • 5 lumbar vertebrae, the lumbar spine ;
  • 5 vertebrae of the sacrum, the sacral rachis ;
  • coccygeal vertebrae, the coccygeal rachis .

Each vertebra has a cylindrical vertebral body on the anterior side and a vertebral foramen on the posterior side that forms a bony canal through which the nerves of the spinal cord can pass.


The joints of the spinal column have the function of allowing the union between the bodies of the vertebrae and the joints between the contiguous vertebral arches.

There are two types of joints in the neck : the atlantooccipital and the atlantoaxial. First, the atlanto- occipital joints , located between the occipital condyles, allow the head and atlas to be joined. Second, the atlantoaxial joints allow the atlas and axis to be connected. There are three atlantoaxial joints, one located between the tooth of the axis and the anterior arch of the atlas and two located between the lateral masses of the first cervical vertebra and the superior facet joints of the second cervical vertebra.

On the other hand, there are the intervertebral joints that allow other vertebrae to join together and the sacroiliac joints, which refer to the joints of the sacrum with the hip bones.

Spinal bones

The spinal column is made up of 33 bones in children (7 cervical vertebrae, 12 thoracic vertebrae, 5 lumbar vertebrae, 4 sacral and 5 coccygeal vertebrae) and 26 bones in adults (7 cervical vertebrae, 12 thoracic vertebrae, 5 vertebrae lumbar, sacrum and coccyx).


The spinal column has four natural curvatures: cervical, thoracic, lumbar and sacral . The position, size and thickness of the vertebrae as well as the intervertebral discs are involved in curvatures.

The curvatures and intervertebral discs fulfill the function of absorbing and distributing the body effort that is made by daily activities or activities of greater physical intensity .

Injuries and diseases associated with the spine

Most of the movements that we carry out, as well as the weights that we carry throughout a day, are transmitted to this bone structure. These repeated actions throughout life, together with certain predispositions such as genetic factors or malformations, can lead to the appearance of acute or chronic pathologies.

Thus, factors such as lack of physical activity, prolonged time sitting at the wheel or at work , among other examples, can be the cause of conditions related to the health of the spine .

Problems that can cause alterations in the structure of the spine or damage the vertebrae and the tissue around them include infections, tumors, and trauma . Likewise, pathologies such as ankylosing spondylitis and scoliosis can be triggered . On the other hand, age can be a determining factor in the appearance of bone changes, causing pathologies such as spinal stenosis and herniated discs .


People often tend to neglect their back health and forget the importance of protecting it. The back has a great influence on our general well-being .

The vertebral column constitutes precisely the back, thus being the central axis of the body. In this way, the spinal column is essential since this structure has the important role of allowing the body to move and support itself, but also to protect the spinal cord , vital to direct the nerve flows between the brain and the body.

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