How many vertebrae are in the spinal column?
The vertebral column, or spinal column, is made up of a total of 33 vertebrae, which are subdivided into five regions: cervical, thoracic, lumbar… READ MORE
What are the 5 sections of the spine?
What are the 5 sections of the spine? The 5 sections of the spine from the top to bottom are: Cervical; Thoracic; Lumbar; Sacral; Coccygeal; How many spine bones are there? There are in total 33 spine bones present in the spine of children. Some of the spine bones at the lower part get fused during development. The adult human spine consists of 26 bones.
What are the five regions of the vertebral column?
- Spinous processes – each vertebra has a single spinous process, centred posteriorly at the point of the arch.
- Transverse processes – each vertebra has two transverse processes, which extend laterally and posteriorly from the vertebral body. ...
- Pedicles – connect the vertebral body to the transverse processes.
What bones are in the spinal column?
Vertebral Column
- Cervical Vertebrae (C1 – C7)
- Thoracic Vertebrae (T1 – T12)
- Lumbar Vertebrae (L1 – L5)
- Purpose of the Vertebrae
- Sacral Spine
Vertebral Bodies in The Cervical Spine
The seven cervical vertebrae begin at the base of the skull and extend down to the thoracic spine. Read Cervical VertebraeThe cervical spine (the n...
Vertebral Bodies in The Thoracic Spine
The thoracic spine makes up the upper back and has twelve vertebral bodies, labeled T1 through T12.See Thoracic Spine Anatomy and Upper Back PainTh...
Vertebral Components of The Lumbar Spine
The lumbar spine has five vertebral bodies, labeled L1-L5, that extend from the lower thoracic spine to the sacrum at bottom of the spine. The vert...
What is the spinal column?
The vertebral column is also known as the spinal column or spine (Figure 1). It consists of a sequence of vertebrae (singular = vertebra), each of which is separated and united by an intervertebral disc. Together, the vertebrae and intervertebral discs form the vertebral column.
How many vertebrae are in the adult vertebral column?
Figure 1. Vertebral Column. The adult vertebral column consists of 24 vertebrae, plus the sacrum and coccyx. The vertebrae are divided into three regions: cervical C1–C7 vertebrae, thoracic T1–T12 vertebrae, and lumbar L1–L5 vertebrae. The vertebral column is curved, with two primary curvatures (thoracic and sacrococcygeal curves) and two secondary curvatures (cervical and lumbar curves).
Why are cervical vertebrae smaller than lumbar vertebrae?
Thus, cervical vertebrae are smaller than lumbar vertebrae due to differences in the proportion of body weight that each supports. Thoracic vertebrae have sites for rib attachment, and the vertebrae that give rise to the sacrum and coccyx have fused together into single bones.
How many vertebrae are there in the human body?
The vertebral column originally develops as a series of 33 vertebrae, but this number is eventually reduced to 24 vertebrae, plus the sacrum and coccyx. The vertebral column is subdivided into five regions, with the vertebrae in each area named for that region and numbered in descending order.
What is the function of the vertebrae and discs?
Together, the vertebrae and intervertebral discs form the vertebral column. It is a flexible column that supports the head, neck, and body and allows for their movements. It also protects the spinal cord , which passes down the back through openings in the vertebrae. Figure 1. Vertebral Column.
How to identify excess vertebral curves?
Excessive vertebral curves can be identified while an individual stands in the anatomical position. Observe the vertebral profile from the side and then from behind to check for kyphosis or lordosis. Then have the person bend forward. If scoliosis is present, an individual will have difficulty in bending directly forward, and the right and left sides of the back will not be level with each other in the bent position.
Why do vertebral curves increase?
These curves increase the vertebral column’s strength, flexibility, and ability to absorb shock. When the load on the spine is increased, by carrying a heavy backpack for example, the curvatures increase in depth (become more curved) to accommodate the extra weight. They then spring back when the weight is removed.
What are the bones in the spinal column?
The bones are stacked on top of each other and securely attached with a disc in between each one. Cervical, thoracic, and lumbar vertebrae in the spinal column. The vertebral bodies act as a support column to hold up the spine.
How are vertebral bodies connected?
The vertebral bodies are attached to a bony arch through which all the nerve roots run. The vertebral arches are interconnected by paired facet joints, which in combination with the disc, create a three joint complex at each vertebral motion segment. This three-joint complex at each vertebral segment ...
What are the structures of the lumbar spine?
Each segment of the lumbar spine is comprised of the following structures: 1 The thick oval segment of bone in the front of the spinal column is called the vertebral body. 2 The vertebral bodies are attached to a bony arch through which all the nerve roots run. 3 The vertebral arches are interconnected by paired facet joints, which in combination with the disc, create a three joint complex at each vertebral motion segment. This three-joint complex at each vertebral segment (the facet joint) provides support and allows for motion. 4 The facet joints have cartilage on each surface and a capsule around them. The cartilage can degenerate as one ages, and lead to degenerative arthritis. 5 The spinous process protrudes from the back of the spine, and these are the ridges that can be felt through the skin along the back of the spine.
What is the function of the cervical spine?
Unlike the rest of the spine, the segments in the cervical spine contain openings in each vertebral body for arteries to carry blood to the brain (vertebral artery running through the transverse foramen). The cervical vertebrae also serve an important function in protecting the spinal cord, ...
What is the top two segment of the cervical spine?
The top two segments are unique: The first cervical segment (called the atlas) is a ring that does not have a vertebral body. This vertebra is named C1. The second vertebral body (called the axis), acts as a post that the first vertebral ring. See The C1-C2 Vertebrae and Spinal Segment.
How many cervical vertebrae are there?
The seven cervical vertebrae begin at the base of the skull and extend down to the thoracic spine. Watch: Cervical Vertebrae Anatomy Animation
Why does the thoracic spine have little motion?
See Thoracic Spine Anatomy and Upper Back Pain. These structures have very little motion because they are firmly attached to the ribs and sternum (breastbone). There is little motion in the thoracic spine, so this region has less risk of injury or wear and tear.
Cervical Vertebrae
The cervical spine breaks down into two parts. The upper cervical C1 and C2, and the lower cervical C3 through C7. The C1 vertebrae are known as the Atlas and the C2 the Axis. The Occipital Bone is a flat bone that forms the back of the head.
Atlas
The Atlas is the first cervical vertebra and is abbreviated as C1. This vertebra supports the skull. It appears different from the other spinal vertebrae, as it resembles a ring and is made up of two masses joined at the front and back by the anterior and posterior arches.
Axis
The Axis is the second cervical vertebra and is abbreviated C2. It is a tooth-like process that projects upward. It is referred to as the odontoid process or dens, which is Latin for tooth. It provides a kind of pivot and collar that allows the head along with the atlas to rotate.
Thoracic Vertebrae
The thoracic vertebrae become larger from T1 through T12. What makes the thoracic spine unique is that it is the only vertebrae that support the ribs and is made up of pedicles, spinous processes, and large neural passageways that help reduce nerve compression.
Lumbar Vertebrae
The lumbar vertebrae increase in size from L1 through L5. These are the vertebrae that take the body’s weight along with any loading force that can create biomechanical stress. The pedicles are longer and wider than the thoracic spine pedicles, and the spinous processes are horizontal and more square.
Sacrum
The sacrum is located behind the pelvis. It consists of five bones that are abbreviated S1 through S5. They are fused together in a triangular shape. The sacrum fits between the hipbones and connects the spine to the pelvis. The last vertebra L5 moves with the sacrum.
Intervertebral Discs
The intervertebral discs make up a quarter of the spinal/vertebral column’s length. There are no discs between the Atlas, Axis, and Coccyx. Discs are not connected to the body’s vascular system and so depend on the endplates to disperse essential minerals and nutrients. The cartilaginous layers keep the discs in place.
What is the spinal column?
The vertebral column, also known as the spinal column, is a flexible column that encloses the spinal cord and also supports the head. It consists of various groups of vertebrae and is divided into five different areas. An internal disk is located between each vertebra. A gelatinous substance called nucleus pulposus can be found in each disk, ...
What is the name of the curvature in the vertebral column?
A normal adult has four curvatures in the vertebral column. Their main purpose is to align the head with a vertical line through the pelvis. Those in the chest and sacrum region are called the kyphosis, while the ones in the lower back and neck area are called lordosis. Last medically reviewed on January 23, 2018.
How many curvatures are there in the vertebrae?
The vertebrae are stacked on top of each other into groups. The groups of the vertebrae consist of: A normal adult has four curvatures in the vertebral column. Their main purpose is to align the head with a vertical line through the pelvis.
What is the function of the vertebral column?
The vertebral column supports the body’s physical structure and nervous system, enabling movement and sensation. Pathology of the spine can lead to debilitating outcomes on quality of life. The vertebral column (spine) defines the animal subphylum Vertebra, or vertebrates, of the phylum Chordata. In humans, it is composed of 33 vertebrae that include 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 4 coccygeal. Along with the skull, ribs, and sternum, these vertebrae make up the axial skeletal system.
How much of the vertebral column is composed of discs?
The discs comprise about 25% of the length of the vertebral column.
What veins drain the spinal cord?
Radicular veins drain the smaller veins of the spinal cord and the internal and external vertebral veins. They empty into segmental and intervertebral veins. Blood flows from these vessels into one of three large vessels depending on the location. The superior vena cava drains the area of the cervical spine. The azygous and hemiazygous veins drain the thoracic area, and the inferior vena cava drains the lower regions of the lumbar and sacral spine.
What are the arteries in the spine?
Spinal arteries originate from branches of larger arteries that supply the internal organs. The subclavian arteries of the neck branch into the vertebral arteries and ascending cervical arteries of the spine. The posterior intercostal arteries of the spine branch from the thoracic aorta while the lumbar arteries of the spine originate from the abdominal aorta. The lateral sacral arteries branch from the internal iliac arteries in the pelvis. Each of these arteries supplying the spine splits into anterior and posterior branches. The anterior branch supplies blood to the vertebral body, and the posterior branch supplies blood to the vertebral arch. Radicular arteries course along the middle, supplying the interior of the vertebral canal and vertebral column.
What is the name of the incomplete closure of the vertebral column and meninges known as?
Spina Bifida: Incomplete closure of the vertebral column and meninges known as a neural tube defect. There are 3 types. In order of increasing severity, they are spina bifida occulta, meningocele, and myelomeningocele. Myelomeningocele is often associated with Arnold-Chiari malformation and tethered spinal cord. [3]
What is the spinal canal?
The spinal canal, a central lumen within each vertebral body, contains the spinal cord. Spinal nerves emerge from the main cord at each vertebral level to make up the sympathetic trunk and splanchnic nerves. The diameter of the spinal canal changes in the different parts of the vertebral column, larger in the cervical and lumbar regions and smaller in the thoracic region.
How many pairs of spinal nerves exit the spinal cord and pass through the intervertebral foramen?
Thirty-one pairs of spinal nerves exit the spinal cord and pass through the intervertebral foramen to innervate the periphery. Meningeal branches of spinal nerves innervate the vertebrae.
What is the function of the vertebral column?
The vertebral column has four main functions: Protection – encloses and protects the spinal cord within the spinal canal. Support – carries the weight of the body above the pelvis. Axis – forms the central axis of the body. Movement – has roles in both posture and movement.
How many bones are in the vertebral column?
The vertebral column is a series of approximately 33 bones called vertebrae, which are separated by intervertebral discs. The column can be divided into five different regions, with each region characterised by a different vertebral structure.
What connects the vertebrae to the transverse processes?
Pedicles – connect the vertebral body to the transverse processes. Lamina – connect the transverse and spinous processes. Articular processes – form joints between one vertebra and its superior and inferior counterparts. The articular processes are located at the intersection of the lamina e and pedicles.
What is the lateral and posterior aspect of each vertebrae?
The vertebral arch forms the lateral and posterior aspect of each vertebrae. In combination with the vertebral body, the vertebral arch forms an enclosed hole – the vertebral foramen. The foramina of all the vertebrae line up to form the vertebral canal, which encloses the spinal cord.
What are the two structures of the vertebrae?
All vertebrae share a basic common structure . They each consist of an anterior vertebral body, and a posterior vertebral arch.
How many lumbar vertebrae are there?
Lumbar Vertebrae. There are five lumbar vertebrae in most humans, which are the largest in the vertebral column. They are structurally specialised to support the weight of the torso. Lumbar vertebrae have very large vertebral bodies, which are kidney shaped.
Why does my cervical spondylosis hurt?
Cervical spondylosis – decrease in the size of the intervertebral foramina, usually due to degeneration of the joints of the spine. The smaller size of the intervertebral foramina puts pressure on the exiting nerves, causing pain.
Why do we need a spine?
The curves in the spine allow the human body to stand upright, and to maintain balance. In addition to protecting the spinal cord, providing rigidity to stand upright and maintaining balance, the spine also provides support for the arms and head as well as providing a place for many muscles, other bones, and organs to attach.
How many bones are in the coccyx?
It is made up of 3-5 bones that become fused together as an adult. The coccyx is attached to several muscles.
