- Also called:
- spinal column, spine, or backbone
- Related Topics:
- vertebra
- intervertebral foramen
- lumbar curve
- sacral curve
- cervical curve
- On the Web:
- National Center for Biotechnology Information - Anatomy, Back, Vertebral Column (Oct. 28, 2026)
vertebral column
-
What is the vertebral column?
The vertebral column, or spine, is a flexible column of vertebrae extending from the neck to the tail in vertebrate animals. It protects the spinal cord, supports the body, and provides attachment points for the pectoral and pelvic girdles and many muscles.
In humans, the vertebral column also transmits body weight during standing and walking. Each vertebra consists of a body, or centrum, and a neural arch that surrounds the vertebral foramen, through which the spinal cord passes. Intervertebral disks cushion the vertebrae.
The vertebral column has cervical, thoracic, lumbar, sacral, and caudal regions. In humans, there are 7 cervical, 12 thoracic, 5 lumbar, 5 fused sacral, and 3 to 5 fused caudal vertebrae.
2 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
Where is the vertebral column found in the human body?
The vertebral column, or backbone, is a flexible column extending from the neck to the tail in vertebrate animals. In humans, it is located in the back, and can be felt as a series of bumps down the back. It consists of a series of bones called vertebrae, separated by cartilaginous intervertebral disks that cushion shock during movement. The vertebral column protects the spinal cord, supports the body, and provides attachment points for the pectoral and pelvic girdles and many muscles. It also transmits body weight during walking and standing.
The vertebral column is characterized by a variable number of curves. The S-shape of the human vertebral column helps with absorbing shock, distributing weight, and maintaining balance while upright.
3 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
What are the main functions of the vertebral column?
The vertebral column, or spine, is a flexible column of vertebrae extending from the neck to the tail. It has several key functions.
- Protection The vertebral column protects the spinal cord, which passes through the vertebral foramen in each vertebra.
- Support It supports the trunk, keeps the head erect, and acts as an anchor for the extremities. The spine also transmits body weight when walking and standing.
- Shock absorption The S-shaped curvature of the spine allows it to absorb shocks from movements like walking, preventing jarring shocks from traveling directly from the pelvic girdle to the head.
- Muscle anchoring The vertebral column serves as an anchoring point for many muscles that move the column or its segments. These include superficial and deep muscles like the erector spinae, which holds the spine erect, and smaller muscles that provide mobility.
2 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
How many bones make up the vertebral column?
The vertebral column, or spine, is a flexible column of bones (vertebrae) that extends from the neck to the tail. It protects the spinal cord, supports the body, and provides attachment points for the pectoral and pelvic girdles and many muscles.
The human vertebral column consists of 7 cervical, 12 thoracic, and 5 lumbar vertebrae. The 5 sacral vertebrae are fused, as are the 3 to 5 caudal vertebrae, which together form the coccyx.
2 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
What are the different regions of the vertebral column called?
The vertebral column, or spine, is a flexible column extending from the neck to the tail, composed of a series of bones called vertebrae. In reptiles, birds, and mammals, the vertebral column is regionalized, with vertebrae differing in shape and function. These regions are:
* Cervical Located in the neck
* Thoracic Located in the chest, articulating with the ribs
* Lumbar Located in the lower back, more robust than other vertebrae
* Sacral Often fused to form the sacrum, which articulates with the pelvic girdle
* Caudal Located in the tailThe numbers of vertebrae in each region vary by species. In humans, there are 7 cervical, 12 thoracic, 5 lumbar, 5 fused sacral, and 3 to 5 fused caudal vertebrae that form the coccyx.
3 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
How does the vertebral column help protect the spinal cord?
The vertebral column protects the spinal cord, which contains nerve fibers traveling to and from the brain, in several ways. The vertebrae, a series of bones extending from the neck to the tail, form a flexible column that surrounds and shields the spinal cord.
Each vertebra has a body and a neural arch, which together create an opening (vertebral foramen) for the spinal cord to pass through. The spinal cord is further protected by the meninges, cerebrospinal fluid, fat, and connective tissue, which fill the space between the nervous and bony tissues. Additionally, tough, resilient intervertebral disks cushion the vertebrae and absorb shocks, while sheets of elastic connective tissue connect the neural arches of adjoining vertebrae.
4 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
vertebral column, in vertebrate animals, the flexible column extending from neck to tail, made of a series of bones, the vertebrae. The major function of the vertebral column is protection of the spinal cord; it also provides stiffening for the body and attachment for the pectoral and pelvic girdles and many muscles. In humans an additional function is to transmit body weight in walking and standing.
Each vertebra, in higher vertebrates, consists of a ventral body, or centrum, surmounted by a Y-shaped neural arch. The arch extends a spinous process (projection) downward and backward that may be felt as a series of bumps down the back, and two transverse processes, one to either side, which provide attachment for muscles and ligaments. Together the centrum and neural arch surround an opening, the vertebral foramen, through which the spinal cord passes. The centrums are separated by cartilaginous intervertebral disks, which help cushion shock in locomotion.
Vertebrae in lower vertebrates are more complex, and the relationships of their parts to those of higher animals are often unclear. In primitive chordates (e.g., amphioxus, lampreys) a rodlike structure, the notochord, stiffens the body and helps protect the overlying spinal cord. The notochord appears in the embryos of all vertebrates in the space later occupied by the vertebral bodies—in some fish it remains throughout life, surrounded by spool-shaped centrums; in other vertebrates it is lost in the developed animal. In primitive chordates the spinal cord is protected dorsally by segmented cartilages—these foreshadow the development of the neural arch of true vertebrae.
" height="20" alt="HEW Logo">
Fish have trunk and caudal (tail) vertebrae; in land vertebrates with legs, the vertebral column becomes further subdivided into regions in which the vertebrae have different shapes and functions. Crocodilians and lizards, birds, and mammals demonstrate five regions: (1) cervical, in the neck, (2) thoracic, in the chest, which articulates with the ribs, (3) lumbar, in the lower back, more robust than the other vertebrae, (4) sacral, often fused to form a sacrum, which articulates with the pelvic girdle, (5) caudal, in the tail. The atlas and axis vertebrae, the top two cervicals, form a freely movable joint with the skull.
The numbers of vertebrae in each region and in total vary with the species. Snakes have the greatest number, all very similar in type. In turtles some vertebrae may be fused to the shell (carapace); in birds all but the cervical vertebrae are usually fused into a rigid structure, which lends support in flight. Most mammals have seven cervical vertebrae; size rather than number account for the variations in neck length in different species. Whales show several specializations—the cervical vertebrae may be either much reduced or much increased in number, and the sacrum is missing. Humans have 7 cervical, 12 thoracic, 5 lumbar, 5 fused sacral, and 3 to 5 fused caudal vertebrae (together called the coccyx).
The vertebral column is characterized by a variable number of curves. In quadrupeds the column is curved in a single arc (the highest portion occurring at the middle of the back), which functions somewhat like a bow spring in locomotion. In humans this primary curve is modified by three more: (1) a sacral curve, in which the sacrum curves backward and helps support the abdominal organs, (2) an anterior cervical curve, which develops soon after birth as the head is raised, and (3) a lumbar curve, also anterior, which develops as the child sits and walks. The lumbar curve is a permanent characteristic only of humans and their bipedal forebears, though a temporary lumbar curve appears in other primates in the sitting position. The cervical curve disappears in humans when the head is bent forward but appears in other animals as the head is raised.
In humans the structure and function of the vertebral column can be affected by certain diseases, disorders, or injuries. Examples include scoliosis, lordosis, and kyphosis, which are deviations from the normal spinal curvature; degenerative diseases, such as osteoarthritis and Baastrup disease (kissing spine syndrome); and tuberculosis of the spine (Pott disease), which is caused by infection of the vertebral column by Mycobacterium tuberculosis.
The trusted destination for professionals, college students, and lifelong learners.
SUBSCRIBE
