Vertebral Column Regions and Structure

The section of the vertebral column made up of the 5 fused sacral vertebrae.

A type of joint found between adjacent vertebrae, allowing for limited movement.

The flexible, resilient discs positioned between vertebrae.

The area at the junction of the lumbar vertebrae and the sacrum.

Composed of four fused coccygeal vertebrae, it represents the most inferior segment of the vertebral column.

The main, weight-bearing part of a vertebra, shaped like a cylinder.

The bony arch that protects the spinal cord, located behind the vertebral body.

A thin, smooth layer of bone surrounding the trabecular bone of the vertebral body, providing strength and protection.

A network of interconnected bony beams inside the vertebral body, providing strength and housing red bone marrow for blood cell production.

The soft tissue inside the vertebral body, responsible for blood cell formation in adults.

The cartilage covering the top and bottom surfaces of the vertebral body, providing smooth surfaces for joint movement and nutrient exchange.

The ring of smooth bone at the periphery of the vertebral body, formed from an anular epiphysis.

Processes that extend from the vertebral arch, providing attachment sites for muscles and ligaments, allowing for movement and support.

The projection extending from the back of the vertebral arch, serving as a point of attachment for muscles and ligaments.

Lateral projections from the vertebral arch, providing attachment for muscles and ligaments.

Paired projections from the vertebral arch, forming joint surfaces with adjacent vertebrae, restricting movement and providing stability.

The opening formed by the vertebral arch, providing passage for the spinal cord, blood vessels, and nerves.

A small notch located above the pedicle of a vertebra, contributing to the formation of the intervertebral foramen.

A large notch located below the pedicle of a vertebra, contributing to the formation of the intervertebral foramen.

The opening formed by the vertebral notches of adjacent vertebrae and the intervertebral disc, providing passage for spinal nerves.

Two bony projections extending posteriorly from the vertebral body, forming part of the vertebral arch.

Broad, flat plates of bone that join in the midline to complete the vertebral arch.

The series of vertebral foramina in the stacked vertebrae, creating a channel for the spinal cord to pass through.

One of the notches observed laterally in the vertebral column, located superior and inferior to each pedicle.

Four bony projections arising from the vertebral arch, each bearing an articular surface (facet), that articulate with corresponding processes of adjacent vertebrae.

The joint formed between the articular processes of adjacent vertebrae, allowing for controlled movement.

The tough, fibrous outer layer of intervertebral discs, composed of concentric rings of collagen fibers.

The soft, gel-like center of an intervertebral disc, acting as a shock absorber.

The strong ligament running along the posterior aspect of the vertebral bodies, helping to stabilize the vertebral column.

The smaller size of cervical vertebrae compared to lumbar vertebrae reflects their reduced load-bearing responsibility.

Despite being thinner than lumbar discs, cervical discs are relatively thick compared to the size of cervical vertebrae.

The unique combination of thick discs, nearly horizontal articular facets, and lighter weight allows for a wide range of motion in the cervical region.

The hole in the transverse process of cervical vertebrae, except for C7.

These arteries and their accompanying veins pass through the transverse foramina in all cervical vertebrae except C7.

The foramen transversarium in C7 is smaller and may be absent, transmitting only small accessory veins.

The transverse processes of cervical vertebrae end in two projections: an anterior tubercle and a posterior tubercle.

The anterior tubercles of vertebra C6 are called carotid tubercles, used to control bleeding from the common carotid arteries by compression in the groove between the tubercle and body.

The anterior rami of the cervical spinal nerves course initially on the transverse processes in grooves for spinal nerves between the tubercles.

Typical cervical vertebrae (C3-C7) are characterized by large vertebral foramina.

These large vertebral foramina accommodate the cervical enlargement of the spinal cord, which is responsible for innervating the upper limbs.

The superior borders of the cervical vertebrae are elevated posteriorly and laterally, resembling a sculpted seat.

The inferior border of the superior cervical vertebra is reciprocally shaped to the superior border of the inferior vertebra.

The unique articulation of cervical vertebrae allows for free flexion, extension, and some lateral flexion, but restricts rotation.

The anterior arch of the atlas (C1) lies anterior to the curved line formed by the anterior surfaces of the C2-C7 vertebral bodies.

The superior aspect of the vertebral body in the cervical spine, which has a hook-like projection.

The raised edge on the superior aspect of the vertebral body in the cervical spine.

A short, two-pronged (bifid) process projecting from the back of the cervical vertebrae (C3-C6), often prominent in white males.

The prominent spinous process of the 7th cervical vertebra (C7).

The first cervical vertebra, lacks a body and spinous process.

The second cervical vertebra with a tooth-like process (dens) that projects upwards.

The upward projection from the body of the axis (C2), serving as the pivot point for head rotation.

A strong ligament connecting the lateral masses of the atlas, spanning behind the dens, preventing displacement.

The upper back vertebrae, characterized by costal facets for rib articulation.

The articular facets on thoracic vertebrae, allowing for rotation and some lateral flexion of the spine.

The area of the spine that allows for the greatest degree of rotation, occurring between vertebrae T5-T8.

The first thoracic vertebra (T1), which has both a full and half facet for rib connections.

The lowest thoracic vertebrae (T9-T12), which have features similar to lumbar vertebrae.

The area of the spine, below the thoracic vertebrae, that is most prone to rotation.

The tooth-like projection on the axis (C2) that allows the atlas (C1) to rotate around it and carries the cranium.

A strong ligament connecting the posterior arch of the atlas (C1) to the anterior arch of the atlas.

A joint formed between the lateral mass of the atlas (C1) and the lateral mass of the axis (C2).

A small projection located on the posterior surface of the vertebral body, found mainly in thoracic vertebrae.

A small projection located on the transverse processes of thoracic vertebrae, providing articulation with the tubercule of the rib.

The area between two adjacent vertebral bodies where the intervertebral disc is located.

The area where the head of the rib articulates with the vertebral body.

The area where the tubercle of the rib articulates with the transverse process of the vertebra.

The coccyx, also known as the tailbone, is a small triangular bone located at the end of the vertebral column. It is typically formed by the fusion of four rudimentary coccygeal vertebrae.

The coccyx is a remnant of the embryonic tail-like structure called the caudal eminence, which is present in developing human embryos.

The coccygeal vertebrae, especially the first one (Co1), may not fully fuse with the rest of the coccyx, and can even remain separate in some individuals.

The anterior surface of the coccyx faces towards the pelvic cavity and is smooth, while the posterior surface features rudimentary articular processes.

The largest and broadest coccygeal vertebra is Co1, its transverse processes connect to the sacrum, and its articular processes form coccygeal cornua that articulate with the sacral cornua.

As we age, Co1 often fuses with the sacrum, and the remaining coccygeal vertebrae typically fuse together to form a single bone.

Although the coccyx doesn't bear weight during standing, it can flex forward when sitting, suggesting it does receive some weight.

The coccyx provides attachment points for muscles like the gluteus maximus and coccygeus, as well as ligaments like the anococcygeal ligament.

The coccyx, although small, plays a role in supporting the pelvic floor and its muscles, contributing to overall pelvic stability.

During life, the auricular surface is covered with hyaline cartilage.

The largest of all movable vertebrae, L5 is characterized by a massive body and transverse processes. It carries the weight of the upper body and is significantly taller anteriorly, contributing to the lumbosacral angle.

A crucial obstetrical landmark, the sacral promontory is the anterior projection of the body of the S1 vertebra on the base of the sacrum.

The sacral canal is the continuation of the vertebral canal within the sacrum. It houses the cauda equina, a bundle of nerve roots.

The sacral foramina are openings on the pelvic and posterior surfaces of the sacrum, providing passage for spinal nerves.

The articulation between the L5 vertebra and the sacrum is called the lumbosacral joint. This joint is critical for the transfer of the weight of the upper body to the pelvis.

The auricular surface is a distinctive area on the lateral surface of the sacrum, shaped like an ear, used for articulation with the ilium.

The sacral hiatus is a U-shaped opening on the dorsal surface of the sacrum resulting from missing laminae and spinous processes. It allows access to the sacral canal.

The sacral cornua are bony projections on either side of the sacral hiatus, serving as landmarks for its location.

The median sacral crest is a prominent longitudinal ridge on the dorsal surface of the sacrum, representing fused spinous processes.

The intermediate sacral crests are ridges on the dorsal surface of the sacrum, representing fused articular processes.

The lateral sacral crests are ridges on the dorsal surface of the sacrum, representing fused transverse processes.

The superior articular processes of the sacrum articulate with the inferior articular processes of the L5 vertebra.

Fusion of sacral vertebrae begins after age 20 and usually completes by middle life. The individual vertebrae are connected by hyaline cartilage during childhood and separated by intervertebral discs.

The C2 spinous process is located in the midline, just below the external occipital protuberance, a bony bump at the back of the skull where the head meets the neck.

The C1 vertebra lacks a spinous process and has a small posterior tubercle that is neither visible nor palpable.

The bifi d spinous processes of C3-C5 are found in the nuchal groove, a depression between neck muscles, but they are difficult to palpate due to the curve of the cervical spine.

The C6 spinous process is easily felt superior to the C7 spinous process (vertebra prominens) because it is longer.

When you flex your head and neck or lean forward significantly, the spinous process of the upper thoracic vertebrae become visible.

A continuous ridge formed by the connected tips of the thoracic spinous processes can be seen in lean individuals. This ridge is part of the supraspinous ligament.

The C7 spinous process is usually the most superior and easily palpable spinous process, although the T1 spinous process is sometimes more prominent.

In thin individuals, the thoracic spinous processes may be visible, while in others, they can be identified by palpation starting at the C7 spinous process and moving down.

The tips of thoracic spinous processes do not correspond to the level of the vertebral bodies because they overlap the vertebra below.

When the back is not flexed or the scapulae are not retracted, the tips of the thoracic spinous processes lie deep to a median longitudinal furrow.

Normally, the tips of the spinous processes are aligned, although the overall line might deviate slightly from the midline. Sudden shifts in alignment might indicate a dislocation or fracture.

The 12th rib, which can be palpated in the posterior axillary line, can be used to confirm the location of the T12 spinous process.

The transverse processes of C1 can be felt laterally by deep palpation between the mastoid processes (behind the ears) and the angles of the jaws.

The carotid tubercle, the anterior tubercle of the C6 transverse process, may be large enough to be palpable. The carotid artery lies anterior to it.

In most individuals, the transverse processes of thoracic vertebrae can be palpated on each side of the spinous processes in the thoracic region.

In lean individuals, the ribs can be palpated from the tubercle to the angle, especially in the lower back, inferior to the scapula.

Lumbar vertebrae are located in the lower back between the thorax and sacrum. They have massive bodies to support the increasing weight towards the inferior end of the vertebral column.